JP6665957B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a substrate processing apparatus.

  2. Description of the Related Art As an exposure apparatus used in a photolithography process, there is known an exposure apparatus that exposes a substrate using a cylindrical or cylindrical mask as disclosed in the following Patent Document (for example, Patent Document 1).

  Not only when using a plate-shaped mask, but also when exposing a substrate using a cylindrical or cylindrical mask, in order to properly project and expose the image of the mask pattern onto the substrate, Patent Document 1 By forming a mark (scale, alignment mark, etc.) for obtaining position information in a predetermined position on the pattern forming surface of the cylindrical mask in a predetermined positional relationship with the pattern, and detecting the scale by an encoder system, A configuration for acquiring position information of a pattern in a circumferential direction (or a rotation axis direction) of a pattern forming surface is described.

  Also, in order to continuously expose a flexible elongate sheet substrate using a cylindrical mask, the elongate sheet substrate is wrapped around a feed roller and supported, and the cylindrical sheet is wound around the feed roller. There is also proposed an exposure apparatus which enables high-productivity device manufacturing (exposure processing) by bringing a mask closer and rotating a feed roller and a cylindrical mask (for example, see Patent Document 2).

JP-A-7-153672 JP-A-8-213305

  In a processing apparatus for processing an object to be processed (sheet substrate) on a curved surface of a cylindrical member such as a feed roller as described above, it is required to accurately detect the position of the cylindrical member in the circumferential direction. Even when a mark (scale) for acquiring position information is engraved on the outer peripheral surface of a cylindrical mask as in Patent Literature 1, there is an error in the encoder measurement result due to a manufacturing error of the scale of the scale or expansion and contraction due to temperature. This may cause the detection accuracy of the position of the cylindrical member in the circumferential direction to decrease.

  An object of an aspect of the present invention is to correct an error generated on a position detection scale when detecting a position of a cylindrical member in a circumferential direction.

  According to a first aspect of the present invention, there is provided a substrate processing apparatus for conveying a long sheet substrate having flexibility in a long direction and performing a predetermined process on the sheet substrate, wherein the sheet processing apparatus is fixed from a center line. A rotating drum that supports the sheet substrate on an outer peripheral surface curved in a cylindrical shape with a radius, and rotates around the center line to convey the sheet substrate in a longitudinal direction; and an outer periphery of the rotating drum of the sheet substrate. A processing unit that performs processing on the sheet substrate at a specific position within a circumferential direction supported by a surface, and a processing unit that is provided in an annular shape along the circumferential direction in which the rotating drum rotates, and the center line of the center line together with the rotating drum. Rotating around, a scale graduation for encoder-measuring a position change in the circumferential direction of the sheet substrate, and a scale azimuth arranged in a first azimuth in the circumferential direction so as to face the scale graduation, and reading the scale graduation A first encoder head, a second encoder head arranged in a second direction rotated in the circumferential direction by an angle θq with respect to the first direction so as to face the scale scale, and reading the scale scale; Is disposed between the first azimuth and the second azimuth with respect to the scale graduation in a third azimuth rotated by an angle θs in the circumferential direction with respect to the second azimuth. A third encoder head for reading the scale, a first reading value of the first encoder head as Cm1, a second reading value of the second encoder head as Cm4, and a third reading value of the third encoder head as Cm5. , The measured value ΔMs calculated by ΔMs = (Cm1 + Cm4) / 2−Cm5 is sequentially calculated every rotation of the scale graduation at a fixed angle α. Stored, a storage unit for storing the error information about the pitch error over the entire circumference of the scale graduation, a substrate processing apparatus including a is provided.

  According to the aspect of the invention, when detecting the position of the cylindrical member in the circumferential direction, it is possible to correct an error generated on the position detection scale.

FIG. 1 is a schematic diagram illustrating an overall configuration of a substrate processing apparatus (exposure apparatus) according to the embodiment. FIG. 2 is a schematic diagram showing the arrangement of the illumination area and the projection area in FIG. FIG. 3 is a schematic diagram showing a configuration of a projection optical system applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 4 is a perspective view of a second drum member (rotary drum) applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 5 is a perspective view for explaining the relationship between a detection probe applied to the substrate processing apparatus (exposure apparatus) of FIG. 1 and a reading apparatus. FIG. 6 is an explanatory diagram showing the positions of the encoder scale disk and the reading device according to the embodiment in a plane orthogonal to the rotation center line. FIG. 7 is an enlarged view schematically showing the scale of the scale. FIG. 8 is a schematic diagram showing a positional relationship between the scale and the encoder head. FIG. 9 is a flowchart showing a procedure for correcting the scale pitch error of the scale. FIG. 10 is a diagram showing a relationship between a scale disk having a scale on an outer peripheral surface and an encoder head. FIG. 11 is a diagram illustrating an example of the correction map. FIG. 12 is a conceptual diagram showing timing when these read values are obtained from a pair of encoder heads. FIG. 13 is a conceptual diagram showing timing when these read values are obtained from a pair of encoder heads. FIG. 14 is a flowchart showing a procedure for correcting a scale error. FIG. 15 is an explanatory diagram for explaining a roundness adjusting mechanism for adjusting the roundness of the encoder scale disk. FIG. 16 is an explanatory diagram for explaining a roundness adjusting mechanism for adjusting the roundness of the encoder scale disk. FIG. 17 is a schematic diagram illustrating a first modification of the substrate processing apparatus (exposure apparatus). FIG. 18 is an explanatory diagram for explaining the position of the reading device when the encoder scale disk according to the first modification of the substrate processing apparatus (exposure apparatus) is viewed in the rotation center line direction. FIG. 19 is a schematic diagram illustrating an overall configuration of a second modification of the substrate processing apparatus (exposure apparatus). FIG. 20 is a schematic diagram illustrating an overall configuration of a third modification of the substrate processing apparatus (exposure apparatus). FIG. 21 is a schematic diagram illustrating an overall configuration of a fourth modification of the substrate processing apparatus (exposure apparatus). FIG. 22 is a signal waveform diagram for briefly explaining the actual reading operation of the scale by the encoder head shown in each of FIGS. 4 to 6, 10 and 16 to 21. FIG. 23 is a view showing the configuration in the case where the scale is formed on the side end surface of the scale disk, as viewed from the direction in which the rotation center line extends, similarly to FIG. FIG. 24 is a cross-sectional view taken along the line A-A ′, in which the configuration of FIG. FIG. 25 is a view of the arrangement of the scale disk and the encoder head as viewed in the XZ plane, similarly to FIG. FIG. 26 is a flowchart illustrating a procedure of a device manufacturing method for manufacturing a device using the substrate processing apparatus (exposure apparatus) according to the embodiment.

  An embodiment (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiments described below. In the following embodiments, a description will be given of an exposure apparatus used in a so-called roll-to-roll method in which various processes for manufacturing one type of device are continuously performed on a substrate. In the following, an XYZ rectangular coordinate system is set, and the positional relationship between the components will be described with reference to the XYZ rectangular coordinate system. As an example, a predetermined direction in the horizontal plane is an X-axis direction, a direction orthogonal to the X-axis direction in the horizontal plane is a Y-axis direction, and a direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, the vertical direction) is the Z-axis direction. And

  FIG. 1 is a schematic diagram illustrating an overall configuration of a substrate processing apparatus (exposure apparatus) according to the embodiment. FIG. 2 is a schematic diagram showing the arrangement of the illumination area and the projection area in FIG. FIG. 3 is a schematic diagram showing a configuration of a projection optical system applied to the substrate processing apparatus (exposure apparatus) of FIG. As shown in FIG. 1, the substrate processing apparatus 11 includes an exposure apparatus (processing unit) EX and a sheet substrate transfer device (hereinafter, appropriately referred to as a transfer device) 9. The exposure apparatus EX is supplied with a substrate P (a sheet, a film, or the like) by the transport device 9. For example, a flexible (flexible) long sheet substrate P pulled out from a supply roll (not shown) is sequentially processed by a substrate processing apparatus (exposure apparatus) 11 through a pre-process substrate processing apparatus, There is a device manufacturing system in which the sheet is sent to a post-process substrate processing apparatus by the transfer device 9 and then wound up by a collection roll. In this manner, the substrate processing apparatus 11 can be used as a part of a device manufacturing system (a flexible display manufacturing line).

  The exposure apparatus EX serving as the substrate processing apparatus 11 is a so-called scanning exposure apparatus, and drives the rotation of the cylindrical mask DM and the feeding of the flexible substrate P in synchronization with each other, while forming a pattern formed on the cylindrical mask DM. Is projected onto the substrate P via the projection optical system PL (PL1 to PL6) having the same magnification (× 1). In the exposure apparatus EX shown in FIG. 1, the Y axis of the XYZ orthogonal coordinate system is set in parallel with the rotation center line AX1 of the first drum member 21 constituting the cylindrical mask DM. Similarly, the rotation center line AX2 of the second drum member 22 as a cylindrical member that indicates a part of the substrate P in the longitudinal direction as a cylindrical shape is set in parallel with the Y axis of the XYZ orthogonal coordinate system.

  As shown in FIG. 1, the exposure apparatus EX includes a mask holding device 12, an illumination mechanism IU, a projection optical system PL, and a control device 14. The exposure apparatus EX rotates (rotates) the cylindrical mask DM held by the mask holding device 12 and transfers the substrate P by the transfer device 9. A part (illumination region IR) of the cylindrical mask DM held by the mask holding device 12 together with the illumination mechanism IU is illuminated by the illumination light beam EL1 with uniform brightness. The projection optical system PL projects the image of the pattern in the illumination area IR on the cylindrical mask DM onto a part (projection area PA) of the substrate P being transported by the transport device 9. With the movement of the cylindrical mask DM, a portion on the cylindrical mask DM arranged in the illumination region IR changes. Further, a portion on the substrate P arranged in the projection area PA changes with the movement of the substrate P. By doing so, an image of a predetermined pattern (mask pattern) formed on the surface of the cylindrical mask DM is projected on the cylindrical surface of the substrate P via the projection optical system PL (PL1 to PL6). . The control device 14 controls each unit of the exposure apparatus EX and causes each unit to execute a process. In the present embodiment, the control device 14 controls the transport device 9.

  The control device 14 may be a part or all of a higher-level control device that integrally controls a plurality of substrate processing apparatuses of the device manufacturing system described above. Further, the control device 14 may be controlled by a higher-level control device and may be a device different from the higher-level control device. The control device 14 includes, for example, a computer system. The computer system includes, for example, a CPU (Central Processing Unit), various memories, an OS (Operating System), and hardware such as peripheral devices. The operation sequence, parameters, and the like of each unit of the substrate processing apparatus 11 are stored in a computer-readable recording medium in the form of a computer program, and various processes are performed by reading and executing this program by a computer system.

  The computer system also includes a homepage providing environment (or display environment) if it can be connected to the Internet or an intranet system. The computer-readable recording medium includes a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in the computer system. The computer-readable recording medium dynamically holds the computer program for a short time, such as a communication line for transmitting the program through a network such as the Internet or a communication line such as a telephone line. In this case, a program that holds a program for a certain period of time, such as a volatile memory in a computer system serving as a server or a client, is also included. Further, the computer program may be for realizing a part of the function of the substrate processing apparatus 11, or may be for realizing the function of the substrate processing apparatus 11 in combination with a program already recorded in the computer system. The higher-level control device can be realized using a computer system, similarly to the control device 14.

  As shown in FIG. 1, the mask holding device 12 includes a first drum member 21 that holds the cylindrical mask DM, a guide roller 23 that supports the first drum member 21, and a first drive unit 26 that is controlled by a control device 14. A drive roller 24 for driving the first drum member 21 and a first detector 25 for detecting the position of the first drum member 21 are provided.

  The first drum member 21 is a cylindrical member having a curved surface that is curved with a fixed radius from a rotation center line AX1 (hereinafter, also appropriately referred to as a first center axis AX1) serving as a predetermined axis. To rotate. The first drum member 21 has a first surface P1 on which the illumination region IR of the cylindrical mask DM is arranged, and the first surface P1 has a line segment (generating line) formed by a first central axis parallel to the line segment. It is a cylindrical surface formed by rotating around AX1. The cylindrical surface is, for example, an outer peripheral surface of a cylinder or an outer peripheral surface of a cylinder. The first drum member 21 is made of, for example, glass or quartz, has a cylindrical shape with a certain thickness, and the outer peripheral surface (cylindrical surface) is the first surface P1. That is, in the present embodiment, the illumination region IR of the cylindrical mask DM is curved in a cylindrical shape having a constant radius r1 from the rotation center line AX1. As described above, the first drum member 21 has a curved surface (a cylindrical surface having a predetermined curvature) curved with a constant radius from the rotation center line AX1.

  The cylindrical mask DM is formed, for example, as a transmission-type planar sheet mask in which a pattern is formed on one surface of a strip-shaped ultra-thin glass plate (for example, having a thickness of 100 μm to 500 μm) having a high flatness with a light shielding layer such as chrome. Is done. The mask holding device 12 is used in a state where a cylindrical mask DM made of an ultra-thin glass plate is curved following the curved surface of the outer peripheral surface of the first drum member 21 and wound (attached) to this curved surface. The cylindrical mask DM has a pattern non-formation area where no pattern is formed, and the pattern non-formation area is attached to the first drum member 21. The cylindrical mask DM can be attached to and detached from the first drum member 21.

  Note that, instead of forming the cylindrical mask DM from an extremely thin glass plate and winding the cylindrical mask DM around the first drum member 21 made of a transparent cylindrical base material, the first drum member 21 is manufactured from a transparent cylindrical base material such as quartz. Alternatively, a mask pattern using a light-shielding layer such as chrome may be directly formed on the outer peripheral surface. Also in this case, the first drum member 21 functions as a support member for the pattern of the cylindrical mask DM.

  The first detector 25 optically detects the rotational position of the first drum member 21, and is composed of, for example, a rotary encoder. The encoder may be of the absolute type or of the increment type. The first detector 25 outputs information indicating the detected rotational position of the first drum member 21, for example, a two-phase signal from an encoder head to be described later to the control device 14. The first drive unit 26 including an actuator such as an electric motor adjusts a torque and a rotation speed for rotating the drive roller 24 according to a control signal input from the control device 14. The control device 14 controls the rotation position of the first drum member 21 by controlling the first driving unit 26 based on the detection result by the first detector 25. Then, the control device 14 controls one or both of the rotation position and the rotation speed of the cylindrical mask DM held on the first drum member 21.

  The transport device 9 includes a driving roller DR4, a first guide member 31, a second drum member 22, which forms a second surface P2 on which the projection area PA of the substrate P is arranged, a second guide member 33, driving rollers DR4, DR5, A second detector 35 and a second driver 36 are provided.

  In the present embodiment, the substrate P transported to the drive roller DR4 from the upstream side of the transport path of the substrate P, that is, from the side opposite to the transport (movement) direction of the substrate P, passes through the first guide via the drive roller DR4. It is transported to the member 31. The substrate P that has passed through the first guide member 31 is transported to the second guide member 33 while being supported on the surface of the cylindrical or columnar second drum member 22 having a radius r2. The substrate P via the second guide member 33 is transported downstream of the transport path. The rotation center line AX2 of the second drum member 22 and the rotation center lines of the drive rollers DR4 and DR5 are both set to be parallel to the Y axis.

  The first guide member 31 and the second guide member 33 adjust the tension in the transport direction acting on the substrate P in the transport path, for example, by moving in the transport direction of the substrate P. Further, the first guide member 31 (and the drive roller DR4) and the second guide member 33 (and the drive roller DR5) are, for example, in the width direction of the substrate P (the direction orthogonal to the transport direction of the substrate P, the Y direction). The position of the substrate P wound around the outer periphery of the second drum member 22 in the Y direction can be adjusted. The transport device 9 only needs to be able to transport the substrate P along the projection area PA of the projection optical system PL, and the configuration of the transport device 9 can be appropriately changed.

  The second drum member 22 is a cylindrical member having a curved surface (a cylindrical surface having a predetermined curvature) curved at a constant radius from a rotation center line AX2 (hereinafter, also appropriately referred to as a second central axis AX2) serving as a predetermined axis. , A rotary drum that rotates around the second central axis AX2. The second drum member 22 forms a second surface (support surface) P2. The second surface P2 is a portion of the substrate P on which the image forming light beam from the projection optical system PL is projected, and supports a portion including the projection area PA in an arc shape (cylindrical shape). In the present embodiment, the second drum member 22 is a part of the transport device 9 and also serves as a support member (substrate stage) that supports the substrate P to be exposed. That is, the second drum member 22 may be a part of the exposure apparatus EX. Thus, the second drum member 22 is rotatable around its rotation center line AX2 (second center axis AX2), and the substrate P follows the outer peripheral surface (cylindrical surface) on the second drum member 22. The projection area PA is arranged on a part of the curved substrate P. For this reason, the board | substrate P will turn in the peripheral surface part containing the projection area PA among the cylindrical surfaces of radius r2.

  In the present embodiment, the second drum member 22 is rotated by a torque supplied from a second driving unit 36 including an actuator such as an electric motor. The second detector 35 is constituted by, for example, a rotary encoder or the like, and optically detects the rotational position of the second drum member 22. The second detector 35 outputs information indicating the detected rotational position of the second drum member 22 (for example, two-phase signals from encoder heads EN1, EN2, EN3, EN4, and EN5 described later) to the control device 14. . The second driving unit 36 adjusts the torque and the rotation speed for rotating the second drum member 22 according to the control signal supplied from the control device 14. The control device 14 controls the rotation position of the second drum member 22 by controlling the second driving unit 36 based on the detection result of the second detector 35, and controls the first drum member 21 (the cylindrical mask DM). The second drum member 22 is moved synchronously (synchronous rotation). The details of the second detector 35 will be described later.

  The exposure apparatus EX is an exposure apparatus on the assumption that a projection optical system PL of a so-called multi-lens system is mounted. The projection optical system PL includes a plurality of projection modules that project a part of an image in the pattern of the cylindrical mask DM. For example, in FIG. 1, the rotation center line AX1 of the cylindrical mask DM and the second center axis AX2 of the second drum member 22 are located on the left side of the center plane P3 parallel to the YZ plane. On the opposite side), three projection modules (projection optical systems) PL1, PL3, and PL5 are arranged at regular intervals in the Y direction, and three projection modules (projection optical systems) are also provided on the right side of the center plane P3 (on the side in which the substrate P is transported). (Optical system) PL2, PL4, PL6 are arranged at regular intervals in the Y direction.

  In such a multi-lens type exposure apparatus EX, the ends in the Y direction of the areas (projection areas PA1 to PA6) exposed by the plurality of projection modules PL1 to PL6 are overlapped with each other by scanning, so that a desired pattern is formed. Project the whole image. In such an exposure apparatus EX, even when the size of the pattern on the cylindrical mask DM in the Y direction becomes large and the necessity of handling a substrate P having a large width in the Y direction arises, the projection module PL and the projection module PL Since it is only necessary to add a module on the illumination mechanism IU side corresponding to the module PL in the Y direction, there is an advantage that the display panel size (width of the substrate P) can be easily increased.

  Note that the exposure apparatus EX need not be a multi-lens type. For example, when the dimension of the substrate P in the width direction is small to some extent, the exposure apparatus EX may project an image of the entire width of the pattern onto the substrate P by one projection module. Further, each of the plurality of projection modules PL1 to PL6 may project a pattern corresponding to one device. That is, the exposure apparatus EX may project the patterns for a plurality of devices in parallel by the plurality of projection modules.

  The illumination mechanism IU includes a light source device 13 and an illumination optical system. The illumination optical system includes a plurality (for example, six) of illumination modules IL arranged in the Y-axis direction corresponding to each of the plurality of projection modules PL1 to PL6. The light source device 13 includes, for example, a lamp light source such as a mercury lamp, a solid light source such as a laser diode, a light emitting diode (LED), or a gas laser light source. Illumination light emitted from the light source device is, for example, bright lines (g-line, h-line, i-line) emitted from a lamp light source, far ultraviolet light (DUV light) such as KrF excimer laser light (wavelength 248 nm), or ArF excimer laser light. (Wavelength 193 nm). The illumination light emitted from the light source device 13 has a uniform illuminance distribution and is distributed to a plurality of illumination modules IL via a light guide member such as an optical fiber.

  Each of the plurality of illumination modules IL includes a plurality of optical members such as lenses. In the present embodiment, light emitted from the light source device 13 and passing through any of the plurality of illumination modules IL is referred to as an illumination light beam EL1. Each of the plurality of illumination modules IL includes, for example, an integrator optical system, a rod lens, a fly-eye lens, and the like, and illuminates the illumination region IR with the illumination light beam EL1 having a uniform illuminance distribution. In the present embodiment, the plurality of illumination modules IL are arranged inside the cylindrical mask DM. Each of the plurality of illumination modules IL illuminates each illumination region IR of the mask pattern formed on the outer peripheral surface of the cylindrical mask DM from inside the cylindrical mask DM.

  FIG. 2 is a diagram showing the arrangement of the illumination area IR and the projection area PA in the present embodiment. FIG. 2 is a plan view of the illumination area IR on the cylindrical mask DM arranged on the first drum member 21 when viewed from the −Z side (the left side view in FIG. 2). A plan view (right view in FIG. 2) of the projection area PA on the placed substrate P as viewed from the + Z side is illustrated. The symbol Xs in FIG. 2 indicates the rotation direction (moving direction) of the first drum member 21 (cylindrical mask DM) or the second drum member 22.

  The plurality of illumination modules IL respectively illuminate the first to sixth illumination regions IR1 to IR6 on the cylindrical mask DM. For example, the first illumination module IL illuminates a first illumination region IR1, and the second illumination module IL illuminates a second illumination region IR2.

  The first illumination region IR1 is described as a trapezoidal region elongated in the Y direction. However, in the case of a projection optical system that forms an intermediate image plane, such as a projection optical system (projection module) PL, the position of the intermediate image is set. A field stop plate having a trapezoidal opening can be arranged. Therefore, the first illumination region IR1 may be a rectangular region including the trapezoidal opening. The third illumination region IR3 and the fifth illumination region IR5 are each a region having the same shape as the first illumination region IR1, and are arranged at regular intervals in the Y-axis direction. The second illumination region IR2 is a trapezoidal (or rectangular) region symmetrical to the first illumination region IR1 with respect to the center plane P3. The fourth illumination region IR4 and the sixth illumination region IR6 are each a region having the same shape as the second illumination region IR2, and are arranged at regular intervals in the Y-axis direction.

  As shown in FIG. 2, each of the first to sixth illumination regions IR1 to IR6 is a hypotenuse portion of a trapezoidal illumination region adjacent in the Y-axis direction when viewed along the circumferential direction of the first surface P1. Are arranged so that the triangular portions overlap (overlap). Therefore, for example, the first area A1 on the cylindrical mask DM that passes through the first illumination area IR1 due to the rotation of the first drum member 21 becomes the cylindrical mask DM that passes through the second illumination area IR2 due to the rotation of the first drum member 21. Partially overlaps the upper second area A2.

  In the present embodiment, the cylindrical mask DM includes a pattern formation region A3 where a pattern is formed, and a pattern non-formation region A4 where a pattern is not formed. The pattern non-formation area A4 is arranged so as to surround the pattern formation area A3 in a frame shape, and has a characteristic of shielding the illumination light beam EL1. The pattern formation area A3 of the cylindrical mask DM moves in the movement direction Xs with the rotation of the first drum member 21, and the respective partial areas in the Y-axis direction of the pattern formation area A3 are the first to sixth illumination areas. Passes one of IR1 to IR6. That is, the first to sixth illumination regions IR1 to IR6 are arranged so as to cover the entire width of the pattern formation region A3 in the Y-axis direction.

  As shown in FIG. 1, each of the plurality of projection modules PL1 to PL6 arranged in the Y-axis direction has a one-to-one correspondence with each of the first to sixth lighting modules IL, and is illuminated by the corresponding lighting module IL. An image of a partial pattern of the cylindrical mask DM appearing in the illumination area IR to be projected is projected onto each projection area PA on the substrate P. For example, the first projection module PL1 corresponds to the first illumination module IL, and transfers the image of the pattern of the cylindrical mask DM in the first illumination region IR1 (see FIG. 2) illuminated by the first illumination module IL onto the substrate P. To the first projection area PA1. The third projection module PL3 and the fifth projection module PL5 correspond to the third to fifth illumination modules IL, respectively. The third projection module PL3 and the fifth projection module PL5 are arranged at positions overlapping the first projection module PL1 when viewed from the Y-axis direction.

  The second projection module PL2 corresponds to the second illumination module IL, and transfers the image of the pattern of the cylindrical mask DM in the second illumination region IR2 (see FIG. 2) illuminated by the second illumination module IL onto the substrate P. To the second projection area PA2. The second projection module PL2 is disposed at a symmetrical position with respect to the first projection module PL1 with respect to the center plane P3 when viewed from the Y-axis direction.

  The fourth projection module PL4 and the sixth projection module PL6 are arranged corresponding to the fourth and sixth illumination modules IL, respectively. The fourth projection module PL4 and the sixth projection module PL6 are viewed from the Y-axis direction. It is arranged at a position overlapping with the second projection module PL2. With such an arrangement, the odd-numbered first projection area PA1, third projection area PA3, and fifth projection area PA5 are displaced from the center plane P3 by a fixed amount in the −X direction and arranged in a line in the Y-axis direction. Is done. The even-numbered second projection area PA2, fourth projection area PA4, and sixth projection area PA6 are arranged in a line in the Y-axis direction while being shifted from the center plane P3 by a certain amount in the + X direction.

  In this embodiment, light reaching each of the illumination regions IR1 to IR6 on the cylindrical mask DM from each of the illumination modules IL of the illumination mechanism IU is defined as an illumination light beam EL1. Further, the light that has been subjected to intensity distribution modulation according to the pattern of the cylindrical mask DM appearing in each of the illumination regions IR1 to IR6, is incident on each of the projection modules PL1 to PL6, and reaches each of the projection regions PA1 to PA6 is formed into an imaging light flux EL2. And Then, of the imaging light flux EL2 reaching each of the projection areas PA1 to PA6, the principal ray passing through each central point of the projection areas PA1 to PA6 is, as shown in FIG. 1, the second central axis AX2 of the second drum member 22. From the center plane P3, they are arranged at positions (specific positions) at an angle θ in the circumferential direction with respect to the center plane P3.

  In each of the first to sixth projection areas PA1 to PA6, an end (trapezoidal triangular portion) between projection areas (odd and even) adjacent to each other in a direction parallel to the second central axis AX2 is the second surface. They are arranged so as to overlap in the circumferential direction of P2. Therefore, for example, the third area A5 on the substrate P passing through the first projection area PA1 due to the rotation of the second drum member 22 is on the substrate P passing through the second projection area PA2 due to the rotation of the second drum member 22. It partially overlaps with the fourth area A6. Each of the first projection area PA1 and the second projection area PA2 is configured such that an exposure amount in an area where the third area A5 and the fourth area A6 overlap is substantially the same as an exposure amount in a non-overlapping area. The shape and the like are set.

  Next, a detailed configuration of the projection optical system PL of the present embodiment will be described with reference to FIG. In the present embodiment, each of the second to fifth projection modules PL2 to PL5 has the same configuration as the first projection module PL1. Therefore, the configuration of the first projection module PL1 will be described as a representative of the projection optical system PL, and description of each of the second projection module PL2 to the fifth projection module PL5 will be omitted.

  The first projection module PL1 shown in FIG. 3 includes a first optical system 41 that forms an image of the pattern of the cylindrical mask DM arranged in the first illumination region IR1 on the intermediate image plane P7, and the first optical system 41. A second optical system for re-imaging at least a part of the formed intermediate image on the first projection area PA1 of the substrate P, and a first field stop 43 arranged on an intermediate image plane P7 on which the intermediate image is formed. .

  Further, the first projection module PL1 includes a focus correction optical member 44, an image shift correction optical member 45, a rotation correction mechanism 46, and a magnification correction optical member 47. The focus correction optical member 44 is a focus adjustment device that finely adjusts a focus state of a pattern image (hereinafter, referred to as a projection image) of a mask formed on the substrate P. The image shift correction optical member 45 is a shift adjustment device that slightly shifts the projected image in the image plane. The magnification correcting optical member 47 is a shift adjusting device for finely correcting the magnification of the projected image. The rotation correction mechanism 46 is a shift adjustment device for slightly rotating the projection image in the image plane.

  The imaging light flux EL2 from the pattern of the cylindrical mask DM exits from the first illumination region IR1 in the normal direction (D1), passes through the focus correction optical member 44, and enters the image shift correction optical member 45. The imaging light beam EL2 transmitted through the image shift correction optical member 45 is reflected by the first reflecting surface (plane mirror) p4 of the first deflecting member 50, which is an element of the first optical system 41, and passes through the first lens group 51. The light is reflected by the first concave mirror 52 arranged at the pupil position, passes through the first lens group 51 again, is reflected by the second reflecting surface (plane mirror) p5 of the first deflecting member 50, and enters the first field stop 43. . The image forming light beam EL2 that has passed through the first field stop 43 is reflected by the third reflecting surface (plane mirror) p8 of the second deflecting member 57, which is an element of the second optical system 42, passes through the second lens group 58, and is pupil. The light is reflected by the second concave mirror 59 disposed at the position, passes through the second lens group 58 again, is reflected by the fourth reflecting surface (plane mirror) p9 of the second deflecting member 57, and enters the magnification correcting optical member 47. . The imaging light flux EL2 emitted from the magnification correcting optical member 47 is incident on the first projection area PA1 on the substrate P, and the image of the pattern appearing in the first illumination area IR1 is magnified (×) in the first projection area PA1. Projected in 1).

  When the radius of the cylindrical mask DM shown in FIG. 1 is r1 and the radius of the cylindrical surface of the substrate P wound around the second drum member 22 is r2, and the radius r1 is equal to the radius r2, each projection module PL1 The principal ray of the imaging light beam EL2 on the mask side of PL6 is inclined so as to pass through the central axis AX1 of the cylindrical mask DM. The inclination angle is the same as the inclination angle θ (± θ with respect to the center plane P3) of the principal ray of the imaging light beam EL2 on the substrate P side.

  In order to provide the above-described tilt angle θ, the angle θ1 of the first reflecting surface p4 of the first deflection member 50 with respect to the optical axis AX3 shown in FIG. 3 is made smaller by Δθ1 than 45 °, and the second deflection with respect to the optical axis AX4 is performed. The angle θ4 of the fourth reflection surface p9 of the member 57 is reduced by Δθ4 from 45 °. Δθ1 and Δθ4 are set in a relationship of Δθ1 = Δθ4 = θ / 2 with respect to the angle θ shown in FIG.

  FIG. 4 is a perspective view of the second drum member 22 (rotary drum) applied to the substrate processing apparatus (exposure apparatus) of FIG. FIG. 5 is a perspective view for explaining the relationship between a detection probe applied to the substrate processing apparatus (exposure apparatus) of FIG. 1 and a reading apparatus. FIG. 6 is an explanatory diagram illustrating the positions of the encoder scale disk and the reading device according to the embodiment in an XZ plane orthogonal to the rotation center line AX2. In FIG. 4, for convenience, only the second to fourth projection areas PA2 to PA4 are shown, and the first, fifth, and sixth projection areas PA1, PA5, and PA6 are not shown.

  The second detector 35 shown in FIG. 1 optically detects the position (more specifically, the rotational position) of the second drum member 22, and serves as a scale member as shown in FIGS. , An encoder scale disk (disk) SD having a high roundness and encoder heads EN1, EN2, EN3, EN4, and EN5 as reading units.

  The encoder scale disk SD is fixed to one end of the second drum member 22 orthogonal to the rotation axis ST of the second drum member 22. For this reason, the encoder scale disk SD rotates integrally with the rotation axis ST around the rotation center line AX2. The encoder scale disk SD may be fixed to both ends of the second drum member 22. That is, the encoder scale disk SD only needs to be fixed to at least one end of the second drum member 22.

  On the outer peripheral surface of the encoder scale disk SD, a plurality of scales (marked lines) GP are provided as scales for position detection for detecting the circumferential position of the second drum member 22 (cylindrical member) or the amount of position change. Have been. Hereinafter, the scale GP is appropriately referred to as a scale GP. The portion of the encoder scale disk SD where the scale GP is engraved is a scale portion. The plurality of graduations GP are arranged along a direction in which the second drum member 22 rotates, for example, in which grid lines having a pitch of 20 μm are arranged in a ring shape, and together with the second drum member 22, around a rotation axis ST (second central axis AX2). To rotate.

  The encoder heads EN1, EN2, EN3, EN4, and EN5 are arranged around the scale GP as viewed from the rotation axis ST (second rotation center line AX2), facing the scale GP with a constant gap. Each of the encoder heads EN1 to EN5 is a non-contact sensor that projects a measurement beam on the scale GP and photoelectrically detects a beam (diffracted light) reflected on the scale GP. The encoder heads EN1 to EN5 are arranged in different directions (angular positions) in the circumferential direction of the scale disk SD when viewed from the rotation axis ST (second rotation center line AX2) of the second drum member 22. I have.

  Each of the encoder heads EN1 to EN5 is a reading device having a measurement sensitivity (detection sensitivity) with respect to a change in displacement in a tangential direction (in the XZ plane) of the scale GP. As shown in FIG. 4, when the installation orientations of the encoder heads EN1 to EN5 (angular directions in the XZ plane about the rotation center line AX2) are represented by installation orientation lines Le1, Le2, Le3, Le4, and Le5. As shown in FIG. 6, the encoder heads EN1 and EN2 are arranged such that the installation azimuth lines Le1 and Le2 are at an angle ± θ ° with respect to the center plane P3. In the present embodiment, the angle θ is set to 15 ° as an example, but is not limited thereto.

  The projection modules PL1 to PL6 illustrated in FIG. 3 are also processing units that perform exposure processing by irradiating the substrate P with a light beam that becomes a pattern image on the substrate P as an object to be processed. For this reason, the exposure apparatus EX includes a first processing unit including odd-numbered projection modules PL1, PL3, and PL5, and a second processing unit including even-numbered projection modules PL2, PL4, and PL6. On the other hand, when the principal ray (for example, the principal ray passing through the center point of the projection area PA) of the image forming light beam EL2 from each of the first processing unit and the second processing unit is viewed on the substrate P when viewed in the XZ plane. Incident vertically. In this way, the position where the principal ray is incident on the substrate P is a specific position where the substrate P is subjected to processing (here, irradiation of an imaging light beam).

  The specific position is set at a position at an angle ± θ in the circumferential direction from the center plane P3 on the substrate P supported on the outer peripheral surface of the second drum member 22, as viewed from the second center axis AX2 of the second drum member 22. ing. As shown in FIGS. 4 and 6, the installation azimuth line Le1 of the encoder head EN1 is a principal ray passing through the center point of each projection area (projection field) PA1, PA3, PA5 of the odd-numbered projection modules PL1, PL3, PL5. Are arranged so as to coincide with the inclination angle θ with respect to the center plane P3. Similarly, the installation azimuth line Le2 of the encoder head EN2 is the inclination angle of the principal ray passing through the center point of each projection area (projection field) PA2, PA4, PA6 of the even-numbered projection modules PL2, PL4, PL6 with respect to the center plane P3. are arranged so as to coincide with θ. For this reason, the encoder heads EN1 and EN2 read the scale on the scale GP located in the direction connecting each specific position and the second center axis AX2.

  The encoder head EN4 is disposed upstream of the encoder head EN1 in the transport direction of the substrate P, that is, before the exposure position (projection area). Then, the encoder head EN4 is arranged on the installation azimuth line Le4. The installation azimuth line Le4 is at a position where the installation azimuth line Le1 of the encoder head EN1 is rotated by about 90 ° around the axis of the rotation center line AX2 toward the upstream side in the transport direction of the substrate P. The encoder head EN5 is arranged on the installation azimuth line Le5. The installation azimuth line Le5 is at a position where the installation azimuth line Le2 of the encoder head EN2 is rotated by about 90 ° around the axis of the rotation center line AX2 toward the upstream side in the transport direction of the substrate P.

  As exemplified above, the main rays of the imaging light beam EL2 passing through the centers of the odd-numbered projection areas PA1, PA3, and PA5 and the main rays of the imaging light flux EL2 passing through the centers of the even-numbered projection areas PA2, PA4, and PA6. If the inclination angle ± θ with respect to the center plane P3 with respect to the light ray is 15 °, the opening angle between the installation azimuth line Le1 and the installation azimuth line Le2 in the XZ plane is 30 °. Therefore, the opening angle between the installation azimuth line Le4 and the installation azimuth line Le5 in the XZ plane is also approximately 30 °.

  By arranging the encoder heads EN4 and EN5 as described above, the directions of the installation azimuth lines Le4 and Le5 where the encoder heads EN4 and EN5 for reading the scale GP are arranged are in the XZ plane and viewed from the rotation center line AX2. In addition, the principal ray of the imaging light beam EL2 with respect to the substrate P is substantially orthogonal to the direction in which the principal ray enters the specific position of the substrate P. For this reason, even when the second drum member 22 is shifted in the Z direction due to slight backlash (about 2 μm to 3 μm) of the bearing that supports the rotating shaft ST, the shift generates in the projection areas PA1 to PA6. The position error in the direction along the obtained imaging light beam EL2 can be measured with high accuracy by the encoder heads EN1 and EN2.

  The encoder head EN3 is arranged on the installation azimuth line Le3. The installation azimuth line Le3 is such that the installation azimuth line Le2 of the encoder head EN2 rotates substantially 120 ° around the axis of the rotation center line AX2, and the installation azimuth line Le4 of the encoder head EN4 turns around the axis of the rotation center line AX2. It is set at a position rotated by approximately 120 ° in the direction opposite to the rotation direction of the line Le2. That is, when viewed in the XZ plane, the three installation azimuth lines Le2, Le3, Le4 extending from the rotation center line AX2 are set at approximately 120 ° intervals.

  The encoder scale disk SD, which is a scale member, is made of, for example, a metal, glass, or ceramic having a low coefficient of thermal expansion as a base material. The encoder scale disk SD is made to have a diameter as large as possible (for example, 20 cm or more in diameter) in order to increase the resolution of measurement. 4, the diameter of the encoder scale disk SD is smaller than the diameter of the second drum member 22. However, of the outer peripheral surface of the second drum member 22, the diameter of the outer peripheral surface around which the substrate P is wound, By making the diameter of the scale GP of the encoder scale disk SD uniform (substantially the same), the so-called measurement Abbe error can be further reduced.

  The minimum pitch of the graduation GP engraved in the circumferential direction of the encoder scale disk SD is limited by the performance of a graduation marking device or the like that processes the encoder scale disk SD. Therefore, if the diameter of the encoder scale disk SD is increased, the angle measurement resolution corresponding to the minimum pitch can be increased accordingly. When the directions of the installation azimuth lines Le1 and Le2 where the encoder heads EN1 and EN2 for reading the scale GP are arranged are viewed from the rotation center line AX2, the principal ray of the imaging light beam EL2 enters the substrate P with respect to the substrate P. In this case, even if the second drum member 22 is shifted in the X direction due to slight play (about 2 μm to 3 μm) of a bearing that supports the rotation shaft ST, the shift causes the projection. Position errors in the feed direction (Xs) of the substrate P that can occur in the areas PA1 to PA6 can be measured with high accuracy by the encoder heads EN1 and EN2.

  As shown in FIG. 5, an image of a part of the mask pattern projected by the projection optical system PL shown in FIG. 1 and the substrate P are relatively formed on a part of the substrate P supported on the curved surface of the second drum member 22. In order to perform alignment, a plurality of alignment microscopes AMG1 and AMG2 that detect alignment marks and the like formed in advance on the substrate P are provided. The alignment microscopes AMG1 and AMG2 are pattern detection devices arranged around the second drum member 22. The alignment microscopes AMG1 and AMG2 are detection probes for detecting a specific pattern discretely or continuously formed on the substrate P. The detection area by the detection probe is arranged upstream of the specific position in the transport direction of the substrate P.

  As shown in FIG. 5, the alignment microscopes AMG1 and AMG2 have a plurality (for example, four) of detection probes arranged in a line in the Y-axis direction (the width direction of the substrate P). The alignment microscopes AMG1 and AMG2 are detection probes at both ends in the Y-axis direction of the second drum member 22, and can constantly observe or detect alignment marks formed near both ends in the width direction of the substrate P. The alignment microscopes AMG1 and AMG2 are detection probes other than both ends in the Y-axis direction (the width direction of the substrate P) of the second drum member 22, and are formed on the substrate P, for example, in a plurality in the longitudinal direction. It is possible to observe or detect an alignment mark formed in a margin or the like between the pattern forming regions of the display panel.

  As shown in FIG. 5, lines passing through the centers (detection centers) of the observation regions on the substrate P by the alignment microscopes AMG1 and AMG2 and orthogonal to the second central axis AX2 are defined as observation azimuth lines AM1 and AM2. In this case, the observation azimuth lines AM1 of the four alignment microscopes AMG1 are arranged in parallel in the Y-axis direction, and similarly, the observation azimuth lines AM2 of the four alignment microscopes AMG2 are arranged in parallel in the Y-axis direction.

  As shown in FIGS. 5 and 6, when viewed in the XZ plane, the installation azimuth line Le4 of the encoder head EN4 is set to the same azimuth as each observation azimuth line AM1 of the four alignment microscopes AMG1. The installation azimuth line Le5 of the encoder head EN5 is set to the same azimuth as each observation azimuth line AM2 of the four alignment microscopes AMG2.

  As described above, the respective detection probes of the alignment microscopes AMG1 and AMG2 are arranged around the second drum member 22 when viewed from the second central axis AX2. The detection probes of the alignment microscopes AMG1 and AMG2 are arranged such that the direction connecting the position where the encoder heads EN4 and EN5 are arranged and the second central axis AX2 (installation azimuth lines Le4 and Le5) is equal to the second central axis AX2 and the alignment microscope. It is arranged so as to coincide with the direction connecting the detection centers of AMG1 and AMG2. The rotation center lines on which the encoder heads EN4 and EN5 corresponding to the respective observation areas (detection centers) of the alignment microscopes AMG1 and AMG2 and the encoders EN1 and EN2 corresponding to the respective projection areas PA1 to PA6 of the projection modules PL1 to PL6 are arranged. The position in the direction around AX2 is set between a sheet entry area IA where the substrate P starts to contact the second drum member 22 and a sheet separation area OA where the substrate P comes off from the second drum member 22 shown in FIG. You.

  The alignment microscopes AMG1 and AMG2 are arranged before the exposure position (projection area PA). The alignment microscopes AMG1 and AMG2 transmit, for example, an image of an alignment mark (formed in an area within several tens μm to several hundred μm square) formed near the end of the substrate P in the Y direction at a predetermined speed. In this state, image detection (sampling) is performed at a high speed by an image pickup device such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). At the moment when the sampling is performed, the control device 14 stores (latches) the rotation angle position of the encoder scale disk SD sequentially measured by the encoder head EN4, and thereby stores the mark position on the substrate P and the second drum member. A correspondence relationship with the rotation angle position 22 is obtained.

  If the mark detected by the alignment microscope AMG1 is also detected by the subsequent alignment microscope AMG2, the expansion and contraction of the substrate P and the slight slip on the second drum member 22 can be measured. An angular position Φa1 measured by the encoder head EN4 when the alignment microscope AMG1 samples a mark and an angular position Φa2 measured by the encoder head EN5 when the alignment microscope AMG2 samples the same mark are stored.

  An up / down counter (counter) connected to each of the two encoder heads EN4 and EN5 (and EN1, EN2 and EN3) and outputting a measurement value corresponding to an angular position is, for example, an outer periphery of a scale disk SD. It is assumed that the origin mark (not shown) engraved on the surface is simultaneously reset to zero at the moment when it is detected by a specific encoder head (any one of EN1 to EN5) or at an arbitrary time. The difference value between the angular positions Φa1 and Φa2 obtained in this way is compared with the aperture angles Φ0 of the installation azimuth lines Le4 and Le5 of the two alignment microscopes AMG1 and AMG2 that have been precisely calibrated in advance. When there is an error between the difference value (Φa1−Φa2) and the opening angle Φ0, the substrate P slightly moves on the second drum member 22 between the sheet entry area IA and the sheet separation area OA. There is a possibility that it has slipped or expanded or contracted in the feed direction (circumferential direction).

  In general, the position error at the time of patterning is determined according to the fineness and the overlay accuracy of the device pattern formed on the substrate P. For example, a linear pattern having a width of 10 μm is accurately overlapped with the underlying pattern layer. In order to perform the alignment exposure, only an error of a fraction or less thereof, that is, a positional error of about ± 2 μm in terms of the dimension on the substrate P is allowed. In order to realize such high-precision measurement, the measurement direction of the mark image by each of the alignment microscopes AMG1 and AMG2 (the direction of the tangent to the outer periphery of the second drum member 22 in the XZ plane) and the position of each of the encoder heads EN4 and EN5 The measurement direction (the direction of the tangent to the outer circumference of the scale GP in the XZ plane) must be aligned within an allowable angle error.

  As described above, the encoder heads EN4 and EN5 are arranged so as to coincide with the measurement direction of the alignment marks on the substrate P by the alignment microscopes AMG1 and AMG2 (the tangential direction of the circumferential surface of the second drum member 22). . Therefore, when the position of the substrate P (mark) is detected (at the time of image sampling) by the alignment microscopes AMG1 and AMG2, the second drum member 22 (encoder scale disk SD) is orthogonal to the installation azimuth line Le4 or Le5 in the XZ plane. Even in the case of shifting in the circumferential direction (tangential direction), high-accuracy position measurement in consideration of the shift of the second drum member 22 can be performed.

  If the graduation pitch of the graduation GP is always constant, it is determined that there is no speed unevenness in the rotation, and the change intervals of the read values of the encoder heads EN1, EN2, EN3, EN4, and EN5 (the generation time of the up-down pulse to the counter) ) Is constant. However, the deformation of the encoder scale disk SD when attaching the encoder scale disk SD to the second drum member 22, the position (tilt) error when attaching the encoder heads EN1, EN2, EN3, EN4, EN5, the manufacture of the encoder scale disk SD The scale GP may have an inherent error (pitch error of the scale itself, pitch unevenness due to eccentricity, deformation, and the like) due to effects such as accuracy at the time, eccentricity at the time of mounting, and the like. In addition, the scale GP may have an inherent error due to a constantly changing element such as expansion and contraction of the encoder scale disk SD caused by a temperature change during the operation of the substrate processing apparatus 11 or the like. In the present embodiment, a measurement error accompanying the inherent error of the scale GP generated due to the above-described cause is obtained. Then, a correction map (correction amount data) for correcting the inherent error of the scale GP is created based on the obtained measurement error, and each read value (actual measurement value) of the plurality of encoder heads EN1 to EN5 is calculated. Correction is performed based on the correction map, and measurement is performed in which the measurement error due to the inherent error of the scale GP is canceled or reduced.

  In the present embodiment, the correction map for the measurement error caused by the pitch error and the pitch unevenness of the scale of the scale GP is arranged on the outer periphery of the scale disk SD coaxially mounted with the second drum member 22 as a cylindrical member. This is executed based on the actual measured values of the plurality of encoder heads. Here, a correction map is created by the encoder head EN4 as a first reading unit, the encoder head EN5 as a second reading unit, and the control device 14 as a correction unit and a map creation unit. In the present embodiment, for convenience, the encoder head EN4 is used as a first reading unit, and the encoder head EN5 is used as a second reading unit. However, the first reading unit and the second reading unit include at least two of which mounting angle intervals are known in advance. Any number of encoder heads may be used.

  The control device 14 serving as a correction unit calculates a difference value (m4−m5) between a read value by the encoder head EN4 (count value m4 by the counter) and a read value by the encoder head EN5 (count value m5 by the counter), Alternatively, a difference value (K45−) obtained by subtracting a difference value (m4−m5) from a predetermined value corresponding to the angular interval between the encoder head EN4 and the encoder head EN5 (for example, a value corresponding to the number of scales between the heads and K45). Based on m4-m5), a pitch error of the scale generated over one round of the scale GP is obtained for each predetermined angular position from the origin position of the scale GP, for example. Then, the control device 14 stores the data of the scale pitch error for one round of the scale GP as a correction map, and based on the correction map, the read value of the encoder head EN4, the read value of the encoder head EN5, or another encoder. Each read value of the heads EN1 to EN3 is corrected.

  FIG. 7 is an enlarged view schematically showing the scale of the scale GP. FIG. 8 is a schematic diagram showing a positional relationship between the scale GP and the encoder heads EN4 and EN5. As shown in FIG. 7, the scale of the scale GP is configured by, for example, repeating a convex portion GPt having a rising portion GPa and a falling portion GPb and a concave portion GPU between the adjacent convex portions GPt. In the present embodiment, one convex portion GPt and one concave portion GPU are assumed to be one unit of the scale GP, that is, one pitch of the scale. For simplicity of description, each encoder head EN1 to EN5 outputs an up pulse U when reading the rising portion GPa of the scale, and outputs a down pulse D when reading the falling portion GPb. .

  The scale of the scale GP is determined by the distance SS1 from the rising portion GPa to the rising portion GPa of the adjacent scale GP or the distance SS2 from the falling portion GPb to the falling portion GPb of the adjacent scale GP is determined by the pitch between the scales (interval). )become. Assuming that the scale pitch determined at the time of designing the encoder scale disk SD is SS, the distance SS1 or SS2 matches the scale pitch SS at any part on the scale GP if the scale GP is manufactured correctly. .

  Therefore, when the scale GP moves in the direction indicated by the arrow R in FIG. 7, when viewed from the pulse output by the encoder head EN, when two up pulses U and one down pulse U are output, or When two down pulses D and one up pulse U are output, the outer peripheral surface (scale GP) of the encoder scale disk SD (see FIG. 6) moves (rotates) by the scale pitch SS. Become. Unless the types of pulses output by the encoder head EN are distinguished, the outer peripheral portion of the encoder scale disk SD has moved by the scale pitch SS every time three pulses are detected.

  In actual encoder measurement, a two-phase signal (sine wave and cosine wave) is generated from the encoder head, and an interpolation signal process for further subdividing the graduation pitch SS is performed based on the two-phase signal. . For this reason, the up pulse U and the down pulse D actually counted by the digital counter are generated at positions where the scale pitch SS is evenly divided into several tenths to several tenths.

  FIG. 8 schematically shows a plurality of graduations of a graduation GP provided on an outer peripheral portion of the scale disk SD, which are linearly arranged. In FIG. 8, it is assumed that the scale GP provided on the outer peripheral portion of the encoder scale disk SD moves in the direction indicated by the arrow R. The encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit are arranged in this order in the moving direction of the scale GP. When viewed from the scale GP, the two encoder heads EN4 and EN5 relatively move in the direction opposite to the direction in which the scale GP moves.

  As shown in FIG. 6, the pair of encoder heads EN4 and EN5 includes a line connecting the encoder head EN4 and the second central axis AX2 (installation azimuth line Le4) and a line connecting the encoder head EN5 and the second central axis AX2. The central angle (encoder mounting angle) with the (installation azimuth line Le5) is θs. As shown in FIG. 8, the linear distance (head-to-head distance) in the circumferential direction of the scale GP at the position where the pair of encoder heads EN4 and EN5 reads the scale GP on the surface of the encoder scale disk SD is XS.

  When the pair of encoder heads EN4 and EN5 is mounted on a frame or the like of the substrate processing apparatus 11, the encoder mounting angle θs and the head-to-head distance XS are constant. As described above, due to the deformation of the encoder scale disk SD, the accuracy at the time of manufacturing the encoder scale disk SD, the eccentricity at the time of mounting, the expansion and contraction of the encoder scale disk SD due to the temperature change, etc., the scale pitch SS becomes equal to that of the encoder scale disk SD. It is not always constant in the circumferential direction. For example, when described schematically, as shown in FIG. 8, in the areas a, c, and d on the scale GP, a rising portion GPa and a rising portion GPa stand between one encoder mounting angle θs and one head-to-head distance XS. There are three graduations GP with one set of the descending portion GPb. However, there are 2.5 scales GP in the area b and 6 scales GP in the area e.

  In the example shown in FIG. 8, when the scale pitch SS is a design value, for example, a specified number (three in this example) of scales GP exists between one encoder mounting angle θs and one head-to-head distance XS. It shall be. Actually, the number of the scales GP existing between one encoder mounting angle θs and one head-to-head distance XS is increased or decreased from the above-mentioned prescribed number due to the above-described error factor of the scale GP. In the area a in FIG. 8, the scale pitch is SSa, but in the area b, the number of the scales GP is smaller than the specified number, so that the scale pitch SSb of the area b is larger than the scale pitch SSa of the area a. Further, since the number of the scales GP in the region e is larger than the specified number, the scale pitch SSe in the region e is smaller than the scale pitch SSa.

  For example, it is assumed that the designed scale pitch SS is 100 and the designed head-to-head distance XS is 300. In the regions a, c, and d in FIG. 8, the actual head-to-head distance X calculated based on each value (count by the counter) obtained by reading the scale GP by the encoder heads EN4 and EN5 is 300. This coincides with the designed head-to-head distance XS. On the other hand, in the area b of FIG. 8, the actual head-to-head distance X calculated based on each value (count value by the counter) read by the encoder heads EN4 and EN5 is 250, and the area e is the encoder head EN4 , EN5, the actual head-to-head distance X based on the read value (count value by the counter) is 600.

  Thus, the difference between the designed head distance XS and the actual head distance X is due to the scale pitch error of the scale GP. After the pair of encoder heads EN4 and EN5 are fixed to the device, if the device is installed in an environment at a constant temperature, the head-to-head distance XS does not change. For this reason, for example, a map of the scale pitch error of the scale GP obtained from the read values of the encoder heads EN4 and EN5 based on the distance XS between the heads after the encoder heads EN4 and EN5 are fixed (for each 360 ° angular position per rotation) Error amount or error correction amount). After the map is created, the error amount or the correction amount corresponding to the angular position is mapped based on the scale GP reading value (counter value of the counter) by the encoder heads EN4 and EN5 (or other heads EN1 to EN3). , It is possible to correct a moving distance error in the circumferential direction of the scale GP in real time.

When correcting the actual scale pitch error and the moving distance error of the scale GP, for example, using the scale pitch SS when there is no error in the scale GP, the designed head distance XS, and the actual head distance X, the scale GP is further used. The actual graduation pitch (actual graduation pitch) SSr in the case where an error has occurred is obtained, for example, from equation (1). By using the actual scale pitch SSr, the error of the scale GP can be corrected, and as a result, the error of the moving distance of the scale GP can be corrected.
SSr = SS × XS / X (1)

In addition, the error of the scale GP is corrected based on the number NS of the scales GP (measurement scale line) existing between the head distances XS, which is read by the pair of encoder heads EN4 and EN5, and the movement distance error of the scale GP is corrected. It may be corrected. The number NS of the graduation lines existing between the head-to-head distances XS can also be obtained by counting the up pulse U and the down pulse D obtained from the pair of encoder heads EN4 and EN5 by the counter. When the measurement scale line NS is used, the actual scale pitch SSr can be obtained by Expression (2) including the head-to-head distance XS.
SSr = XS / NS (2)

  The error of the graduation pitch and the error of the movement distance of the graduation GP are determined by the control device 14 as a correction unit of the position detecting device for the cylindrical member, for example, by a calculation using Expression (1) or Expression (2). This is applied as a correction amount for the read value of the encoder heads EN4 and EN5. For this reason, the cylindrical member position detecting device and the substrate processing device 11 including the control device 14 can generate an error map or a correction map even if an error occurs in the scale pitch SS due to deformation of the encoder scale disk SD provided with the scale GP. By using this, the error can be corrected almost in real time, so that accurate position measurement (position measurement in the circumferential direction) of the encoder scale disk SD and the second drum member 22 can be realized. Next, correction of a scale pitch error and a movement distance error will be described.

  FIG. 9 is a flowchart showing a procedure for correcting the scale pitch error of the scale. FIG. 10 is a diagram showing a relationship between a scale disk SD having a scale on the outer peripheral surface and encoder heads EN4 and EN5. FIG. 11 is a diagram illustrating an example of the correction map. When correcting the scale pitch error of the scale GP, as shown in FIG. 10, a head-to-head distance XS between the pair of encoder heads EN4 and EN5 is measured in advance and stored in a storage unit of the control device 14. The head-to-head distance XS is obtained at a position where the pair of encoder heads EN4 and EN5 read the scale GP on the outer peripheral surface of the encoder scale disk SD. The position at which the pair of encoder heads EN4 and EN5 read the scale GP can be a position where the encoder scale disk SD is a perfect circle and the encoder scale disk SD is not eccentric with respect to the rotation center line AX2. . In this case, as shown in FIG. 10, a pair of curved surfaces Pd (scale surfaces of the scale GP) curved from the rotation center line AX2 by a radius (distance from the center to the outer peripheral surface) ra of the design value of the encoder scale disk SD. The distance XS between the heads of the encoder heads EN4 and EN5 is measured. In the example shown in FIG. 10, the scale GP of the encoder scale disk SD rotates (turns) in the direction indicated by the arrow R, that is, from the encoder head EN4 toward the encoder head EN5.

  As shown in FIG. 9, when the processing of the substrate processing apparatus 11 shown in FIG. 1 is not started in step S101 (step S101, No), correction of the scale GP and the like is not performed. In step S101, the process of the substrate processing apparatus 11 is started, and when the scale disk SD is rotating stably (step S101, Yes), in step S102, the control device 14 controls the encoder heads EN4, EN5 at a predetermined timing. These readings (counts of the counter) are obtained from The acquisition at a predetermined timing means that the control device 14 reads each of the encoder heads EN4 and EN5 each time the scale GP of the encoder scale disk SD rotates by a predetermined angle α (degree) about the rotation center line AX2. Acquiring a value, that is, latching and storing the count value of each counter. Hereinafter, the angle α may be appropriately referred to as a rotation angle α. When the encoder scale disk SD is rotating at a constant angular speed (constant peripheral speed), the control device 14 may acquire the read values of both the encoder heads EN4 and EN5 at every predetermined time t. In this example, α (degree) is preferably a divisor of 360, but the angle α is not limited to this. The angle α is determined according to the tendency of the scale pitch error (the fluctuation width of the error and the rate of change in the circumferential direction).

  When the encoder scale disk SD is rotating at a constant angular velocity, the control device 14 acquires these read values from both encoder heads EN4 and EN5 at every time t. When the control device 14 acquires these read values from both the encoder heads EN4 and EN5 at every predetermined angle α, for example, a rotation angle detecting means of the encoder scale disk SD is prepared. Then, the control device 14 acquires these read values from both the encoder heads EN4 and EN5 at each timing when the rotation angle detecting means detects that the encoder scale disk SD has rotated by the angle α. Further, either one of the two encoder heads EN4 and EN5 may be used as the rotation angle detecting means. For example, when the encoder head EN4 is used as a rotation angle detecting unit, the control device 14 transmits the signals from both encoder heads EN4 and EN5 at each timing when the encoder head EN4 detects that the encoder scale disk SD has rotated by the angle α. Obtain these readings. The rotation of the encoder scale disk SD by the angle α can be detected, for example, by the encoder head EN4 detecting the number of scales GP corresponding to the rotation angle α and outputting the number of pulses corresponding thereto.

  Next, proceeding to step S103, the control device 14 determines an actual scale pitch SSr as a correction value of the scale GP based on the read value acquired in step S102. For example, when determining the actual scale pitch SSr using the above-described equation (2), the control device 14 determines the number of measurement scales NS from the read values of the encoder heads EN4 and EN5. The measurement scale number NS is a difference (NSa-NSb) between a reading NSa of the number of scales GP by the encoder head EN4 and a reading NSb of the number of scales GP by the encoder head EN5. Then, the control device 14 reads the head-to-head distance XS stored in its own storage unit, and obtains the actual scale pitch SSr from Expression (2). The actual scale pitch SSr is a correction value of the interval between the scales GP in the range of the angle α (degree). When the actual scale pitch SSr is obtained by using the above equation (2), the distance X between the measurement encoders is obtained from the product of the number NS of measurement scales and the scale pitch SS when there is no error in the scale GP. The number NS of measurement scales may be obtained from the distance XS, the scale pitch SS, and the distance X between the measurement encoders.

  The measurement scale number NS can be obtained, for example, as follows. When the encoder head EN4 reads a position (scale reference position) GPb serving as a reference for a plurality of scales GP of the encoder scale disk SD, the controller 14 resets the encoder head EN4 (0 based on the Z phase of the encoder head EN4). After the point reset), the number of the scales GP detected by the encoder head EN4 is counted. Next, when the encoder head EN5 reads the scale reference position GPb, the control device 14 resets the encoder head EN5 (resets the encoder head EN5 to a zero point based on the Z phase). Then, the control device 14 acquires the number of scales GP of the encoder head EN4 when the encoder head EN5 is reset to 0, and the number of scales GP when the encoder head EN5 reads the scale reference position GPb, that is, 0. And the difference from. This difference is the measurement scale number NS. Thereafter, the control device 14 continues counting the scale GP by the encoder heads EN4 and EN5, and counts the count values (scales) of the read values of both encoder heads EN4 and EN5 at a predetermined angle α or at a predetermined time t. GP count value), the difference is obtained, and this difference is set as a measurement scale number NS at a predetermined angle α or a predetermined time t. In this example, when the encoder scale disk SD makes one revolution, the scale reference position GPb returns to the original position. At this time, the counters connected to each of the encoder heads EN4 and EN5 do not need to be reset. May be.

  When the actual scale pitch SSr (corresponding to the correction value of the scale GP) at a certain angle α is obtained in step S103, the control device 14 associates the actual scale pitch SSr with the angle α in the correction map TBc shown in FIG. Describe. For example, the No. of the correction map TBc. 2, the angle 2 × α and the corresponding actual scale pitch SSr2 (= XS / NS2) are described. The correction map TBc is stored in the storage unit of the control device 14. The control device 14 obtains the actual scale pitch SSr over the entire circumference of the plurality of scales GP (the entire circumference of the encoder scale disk SD). During the processing of the substrate processing apparatus 11, the control device 14 calculates a correction value corresponding to the angle of the encoder scale disk SD detected by at least one of the encoder head EN4 and the encoder head EN5, that is, the actual scale pitch SSr from the correction map TBc. It is read and the error of the scale GP is corrected. As shown in FIG. 6, when the substrate processing apparatus 11 has three or more encoder heads EN1, EN2, EN3, EN4, and EN5, the control device 14 uses the correction map TBc for other than the encoder heads EN4 and EN5. The error of the scale GP may be corrected. Next, proceeding to step S105, if the processing of the substrate processing apparatus 11 is not completed (step S105, No), the control device 14 continues steps S102 to S104, and the processing of the substrate processing apparatus 11 is stopped. When the processing has been completed (Step S105, Yes), the control device 14 ends the correction of the scale GP and the like.

  In the above example, during the processing of the substrate processing apparatus 11, that is, when the processing unit is performing a predetermined processing (for example, exposure processing) on the substrate, the control device 14 determines that the interval between the plurality of scales GP is apparent. Above, it is corrected to be constant. By doing so, the error of the scale GP generated during the operation of the substrate processing apparatus 11, that is, the error of the reading scale interval can be corrected in real time, so that the processing accuracy of the substrate processing apparatus 11 is improved.

  When the scale reference position GPb, which has been at the position of the encoder head EN4, returns to the position of the encoder head EN4, the actual scale pitch SSr is obtained as a correction value of the scale GP for the entire circumference. . The controller 14 may thereafter similarly correct the graduation GP each time the disk SD makes one rotation, or ends the correction of the graduation GP after one rotation of the disk SD, and performs the correction at a predetermined timing (for example, a predetermined time). The correction of the scale GP may be resumed after a lapse of time or when a predetermined temperature change occurs. In the former case, since the correction map TBc is updated as needed, it is possible to quickly respond to deformation or dimensional change of the encoder scale disk SD and the scale GP in a short time. In the latter case, the frequency of updating the correction map TBc can be suppressed, and accordingly, the hardware resources of the control device 14 can be effectively used.

  When the control device 14 acquires these read values from the encoder heads EN4 and EN5, the shorter the acquisition timing or the smaller the interval between the encoder heads EN4 and EN5, the higher the accuracy of correction of the scale GP. The distance between the encoder heads EN4 and EN5 is restricted to some extent by the size of the encoder heads EN4 and EN5 and the balance with other component arrangements. For this reason, there is an advantage that versatility is improved by shortening the timing when acquiring these read values from the encoder heads EN4 and EN5.

  FIG. 12 and FIG. 13 are conceptual diagrams showing timings when acquiring these read values from a pair of encoder heads. In the example described above, each time the plurality of scales GP of the encoder scale disk SD rotate by the predetermined rotation angle α (degree) about the rotation center line AX2, the control device 14 reads these reading values from the encoder heads EN4 and EN5. I got If the rotation angle α (degrees) at this time is a divisor of 360, the encoder heads EN4 and EN5 read the same position every round while the encoder scale disk SD rotates a plurality of times (see FIG. 12). ). In this case, in order to improve the accuracy of correction of the scale GP, it is necessary to reduce the predetermined rotation angle α. However, the rotation angle α cannot be reduced unnecessarily due to restrictions of the apparatus.

  In the present embodiment, since the encoder scale disk SD having a plurality of scales GP is a rotating body (continuous body), it is possible to continuously measure using the encoder heads EN4 and EN5 even if the periodicity of each rotation is not necessarily ensured. It is. Therefore, for example, by setting the rotation angle α (degree) to a number that is not a divisor of 360 degrees, the periodicity of the reading positions of the encoder heads EN4 and EN5 when the encoder scale disk SD rotates a plurality of times is broken. Can be. In particular, by setting α (degree) to a number that is not a divisor of 360 degrees and a prime number, the periodicity described above can be more effectively broken. As a result, even if the predetermined rotation angle α is large, the amount of displacement that occurs each time the plurality of scales GP (encoder scale disk SD) orbits is small, and as a result, the scale GP by the encoder heads EN4 and EN5 is reduced. The measurement interval can be reduced (see FIG. 13).

  For example, the angle α may be a value that does not become a divisor of 360 degrees between about 10 degrees and 35 degrees, and the value of 360 / α is about 1 to 4 digits after the decimal point, and preferably 1 digit after the decimal point. The value may be divisible by up to four digits. As an example, when the angle α is a prime number such as 11 degrees, 17 degrees, 19 degrees, and 23 degrees, 360 / α cannot be divided even by four digits after the decimal point. On the other hand, when the angle α is any one of 12.5 degrees, 16 degrees, 25 degrees, and 28.8 degrees, 360 / α is divisible by one decimal place. When the angle α is 19.2 degrees and 32.0 degrees, 360 / α is divisible by two digits after the decimal point. If the angle α is 12.8 degrees, 360 / α is divisible by three digits after the decimal point. Further, when the angle α is 25.6 degrees, 360 / α is divisible by four digits after the decimal point. Note that when the rotation angle α is between 10 degrees and 35 degrees, angles that are divisors (360 / α is an integer) are 10 degrees, 12 degrees, 14.4 degrees, 15 degrees, 18 degrees, 20 degrees, and 22 degrees. 0.5 degrees, 24 degrees, and 30 degrees. The rotation angle α may be in the range of 1 to 10 degrees, but when avoiding a divisor such that 360 / α is an integer, the rotation angles α are 7 and 9 degrees. Depending on the required resolution of error correction, the difference between the read values of the encoder heads EN4 and EN5 is determined at every rotation angle α of less than 1 degree, for example, every 0.5 degree, and a pitch error map is created. You may.

  FIG. 14 is a flowchart showing a procedure for correcting a scale error. The example shown in FIG. 14 is a case where a pair of encoder heads EN4 and EN5 read each time a plurality of scales GP of the encoder scale disk SD rotate by a predetermined angle α (degree) about the rotation center line AX2. This shows a processing procedure when the rotation angle α is a prime number that is not a divisor of 360. In this example, the rotation angle α can be, for example, 7 degrees, 11 degrees, or the like.

  Steps S201 to S204 are the same as steps S101 to S104 in the above-described example in which α (degree) is a divisor of 360, and a description thereof will be omitted. In step S205, if the encoder scale disk SD has not been rotated to the specified number of revolutions since the start of obtaining the correction value (step S205, No), the control device 14 repeats steps S202 to S205. In step S205, if the encoder scale disk SD has rotated to the specified number of revolutions after starting to obtain the correction value (step S205, Yes), the control device 14 proceeds to step S206. Step S206 is the same as step S105 in the above-described example in which α (degree) is a divisor of 360, and a description thereof will be omitted. The specified rotation speed in step S205 may be two or more rotations. However, as the specified rotation speed increases, the effect of improving the accuracy of correcting the scale GP decreases. Therefore, it is preferable to set the prescribed number of rotations in an appropriate range of two or more rotations.

  Next, the arrangement of the encoder heads EN4 and EN5 will be described. As shown in FIG. 6, the encoder head EN4 serving as the first reading unit and the encoder head EN5 serving as the second reading unit have a second drum member serving as a cylindrical member more than the exposure apparatus EX serving as the processing unit (see FIG. 1). 22 is preferably arranged on the opposite side to the rotation direction. More specifically, it is preferable that the substrate P supported by the second drum member 22 be disposed on the side opposite to the rotation direction of the second drum member 22 with respect to the portion to be exposed by the exposure apparatus EX. That is, the scale GP is read at two places before the portion where the substrate P supported by the second drum member 22 is subjected to the exposure processing by the exposure apparatus EX, and the correction value is obtained. In the example shown in FIG. 6, the rotation direction of the second drum member 22 is a direction from the encoder head EN4 to the encoder head EN5. By arranging the encoder heads EN4 and EN5 in this manner, the position information in the circumferential direction of the second drum member 22 after the scale GP is corrected is fed back to the control of the process (exposure process in this example). Therefore, the processing accuracy is improved.

  In the present embodiment, both the encoder heads EN4 and EN5 are arranged on the side opposite to the rotation direction of the second drum member 22 with respect to the portion where the substrate P is subjected to the exposure processing by the exposure apparatus EX. It may be arranged at a portion to be exposed. For example, the encoder head EN5 may be used as a first reading unit, and the encoder head EN1 may be used as a second reading unit, and a correction value of the scale GP may be obtained based on a difference between the read values.

  In the present embodiment, the alignment microscopes AMG1 and AMG2 are arranged at positions corresponding to the encoder heads EN4 and EN5. Therefore, the change in the surface of the substrate P is measured by the alignment microscopes AMG1 and AMG2, and the processing position is measured. , The change of the substrate P in the above can be predicted and corrected at the time of processing. Further, using the encoder heads EN4 and EN5 and at least one of the encoder heads EN1 and EN2 arranged at a different position, for example, the processing position, the rotation of the rotation center line AX2 (perpendicular to the rotation center line AX2). Of the second drum member 22 or the like, and the processing can be corrected based on the measured value.

  When measuring the deflection of the rotation center line AX2 or the eccentricity of the second drum member 22 or the like, the third reading unit disposed on the side opposite to the encoder heads EN4 and EN5 with respect to the processing position (position of the exposure processing). It is preferable to use the encoder head EN3 (see FIG. 6) together with the encoder heads EN4 and EN5. In this way, before and after the processing position, the measurement results such as the shake of the rotation center line AX2 are compared, and the intermediate value can be used as a correction value for the shake of the rotation center line AX2. In addition, the rotation center line AX2 is measured by using the encoder heads EN4 and EN5 and the encoder head EN3 disposed before and after the processing position, and the rotation center line AX2 is corrected based on the measured value. Accuracy when correcting the shake or the like of AX2 is improved. When the encoder head EN3 is used as the third reading unit, a straight line connecting the encoder head EN5 and the rotation center line AX2 (installation azimuth line Le5) and a straight line connecting the encoder head EN3 and the rotation center line AX2 (installation azimuth line Le3). Is not limited to 210 degrees shown in FIG. 6, and the encoder head EN3 may be on the processing position side.

  When the encoder head EN3 as the third reading unit is used in addition to the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit, the encoder head EN4 and the encoder head EN5 in the circumferential direction of the encoder scale disk SD. Is preferably smaller than the interval between the encoder heads EN5 and EN3. By reducing the interval between the encoder head EN4 and the encoder head EN5, the accuracy of correction of the scale GP can be improved. Further, by increasing the distance between the encoder head EN5 and the encoder head EN3, it is possible to improve the sensitivity when detecting the eccentricity or the like of the second drum member 22.

  Next, an interval at which the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit are arranged will be described. The encoder head EN4 and the encoder head EN5 form a line connecting the encoder head EN4 and the rotation center line AX2 (installation azimuth line Le4) and a line connecting the encoder head EN5 and the rotation center line AX2 (installation azimuth line Le5). It is preferable that the encoder angle θs, which is the central angle, is arranged so as to be an angle other than 90 degrees, 180 degrees, and 270 degrees. In this way, the two encoder heads EN4 and EN5 can also detect the deflection of the rotation center line AX2, the eccentricity of the second drum member 22, and the like. Further, the encoder mounting angle θs is preferably within 45 degrees, and is preferably an angle other than 120 degrees and 240 degrees. In this way, the two encoder heads EN4 and EN5 detect the deflection of the rotation center line AX2 or the eccentricity of the second drum member 22 while improving the accuracy of correction of the scale GP. Next, a case where the substrate processing apparatus 11 has a mechanism for adjusting the roundness of the encoder scale disk SD will be described.

  15 and 16 are explanatory diagrams for explaining a roundness adjusting mechanism for adjusting the roundness of the encoder scale disk. 4 and 5, the diameter of the encoder scale disk SD is smaller than the diameter of the second drum member 22, but the outer peripheral surface of the second drum member 22 around which the substrate P is wound. It is preferable that the diameter of the surface and the diameter of the graduation GP of the encoder scale disk SD be equalized (substantially matched). By doing so, the so-called measurement Abbe error can be further reduced. In this case, the exposure apparatus EX preferably includes a roundness adjusting mechanism Cs for adjusting the roundness of the encoder scale disk SD as shown in FIG.

  The encoder scale disk SD as a scale member is an annular member. The encoder scale disk SD having the scale GP on the outer peripheral surface is fixed to at least one end of the second drum member 22 orthogonal to the second center axis AX2 of the second drum member 22. The encoder scale disk SD has a groove Sc provided on the encoder scale disk SD along the circumferential direction of the second central axis AX2, and a second drum having the same radius as the groove Sc and along the circumferential direction of the second central axis AX2. It faces the groove Dc provided in the member 22. In the encoder scale disk SD, a bearing member SB such as a rolling element (for example, a ball) is interposed between the groove Sc and the groove Dc.

  The roundness adjusting mechanism Cs is provided on the inner peripheral side of the encoder scale disk SD, and includes an adjusting member 60 and a pressing member PP. The roundness adjusting mechanism Cs is, for example, a pressing mechanism that can change the pressing force in a direction parallel to the installation azimuth line Le4 from the second central axis AX2 toward the scale GP. (E.g., eight locations) at a predetermined pitch in the circumferential direction. The adjusting member 60 is inserted into the pressing member PP, and is screwed into the female screw portion FP3 of the encoder scale disk SD and the female screw portion FP4 of the second drum member 22, and the head portion 62 that contacts the pressing member PP. Having. The pressing member PP is an annular fixed plate having a smaller radius than the encoder scale disk SD along the circumferential direction at the end of the encoder scale disk SD. The encoder scale disk SD is fixed to at least one end of the second drum member 22 by a plurality of fastening members, that is, an adjusting member 60 including a male screw portion 61 and a head portion 62 in the circumferential direction of the second drum member 22. Fixed.

  Before the installation azimuth line Le4 is extended to the inner peripheral side of the encoder scale disk SD, an inclined surface FP2 is formed on the inner peripheral side of the encoder scale disk SD, in a section parallel to the second central axis AX2 and including the second central axis AX2. Are formed. The inclined surface FP2 is an inclined surface such that the thickness in a direction parallel to the second central axis AX2 becomes smaller as approaching the second central axis AX2. The inclined surface FP1 is formed on the pressing member PP such that the thickness in the direction parallel to the second central axis AX2 increases as the distance from the second central axis AX2 approaches. The pressing member PP is fixed to the encoder scale disk SD by the adjusting member 60 such that the inclined surfaces FP2 and FP1 face each other.

  The roundness adjusting mechanism Cs transmits the pressing force of the inclined surface FP1 of the pressing member PP to the inclined surface FP2 by screwing the male screw portion 61 of the adjusting member 60 into the female screw portion FP3 of the encoder scale disk SD. A small amount elastically deforms from the inside of the disk SD toward the outer periphery. Conversely, by rotating the male screw portion 61 to the opposite side, the suppressed pressing force of the inclined surface FP1 of the pressing member PP is transmitted to the inclined surface FP2, and a very small amount inward from the outer peripheral side of the encoder scale disk SD. Elastically deform.

  The circularity adjusting mechanism Cs adjusts the diameter of the scale GP in the circumferential direction by a small amount by operating the male screw portion 61 of the adjusting member 60 provided at a plurality of pitches in the circumferential direction about the rotation center line AX2. can do. Further, since the roundness adjusting mechanism Cs can slightly deform the scale GP on the installation orientation lines Le1 to Le5, the diameter of the scale GP in the circumferential direction can be adjusted with high accuracy. Therefore, by operating the adjusting member 60 at an appropriate position in accordance with the roundness of the encoder scale disk SD, the roundness of the scale GP of the encoder scale disk SD can be increased, or the minute eccentricity error with respect to the rotation center line AX2 can be increased. And the accuracy of position detection in the rotation direction with respect to the second drum member 22 can be improved. The adjustment amount adjusted by the roundness adjustment mechanism Cs varies depending on the diameter of the encoder scale disk SD or the radial position of the adjustment member 60, but is at most about several μm.

  As shown in FIG. 16, the encoder scale disk SD is fixed to the second drum member 22 by eight adjusting members 60. In this case, the encoder head EN4 as the first reading unit and the encoder head EN5 as the second reading unit have an encoder mounting angle θs, which is the central angle between the encoder head EN4, the second central axis AX2, and the encoder head EN5, It is preferable that the adjustment member 60 is disposed so as to be smaller than the central angle β formed between the adjacent adjustment member 60 and the second central axis AX2.

  Since the encoder scale disk SD is fixed to the second drum member 22 by the adjustment member 60, there is a possibility that deformation occurs near the adjustment member 60. As described above, by setting θs <β, the encoder heads EN4 and EN5 can reliably detect an error in the scale GP caused by deformation between the adjacent adjustment members 60. As a result, the correction accuracy of the scale GP is improved. Next, a modification of the substrate processing apparatus (exposure apparatus) will be described.

(First Modification of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 17 is a schematic diagram illustrating a first modification of the substrate processing apparatus (exposure apparatus). FIG. 18 is an explanatory diagram for explaining the position of the reading device when the encoder scale disk according to the first modification of the substrate processing apparatus (exposure apparatus) is viewed in the rotation center line direction. In the above-described embodiment, the case where the position in the circumferential direction of the second drum member 22 that supports the substrate P is detected is described as an example. However, the present invention is not limited to this. Even when the position of the first drum member 21 holding the cylindrical mask DM in the circumferential direction is detected as in the exposure apparatus EX1 of the present modified example, the first drum member 21 is detected using a pair of encoder heads. An error of a scale GP (scale) for detecting the position of one drum member 21 in the circumferential direction can be corrected.

  The encoder scale disk SD of the exposure apparatus EX1 is fixed to both ends of the second drum member 22 orthogonal to the rotation axis AX2 of the second drum member 22. The scale GP is provided on the outer peripheral surface of both encoder scale disks SD. For this reason, the scale GP is disposed at both ends of the second drum member 22. The encoder heads EN <b> 1 to EN <b> 5 that read the respective scales GP are arranged on both ends of the second drum member 22.

  The first detector 25 (see FIG. 1) described in the above-described embodiment optically detects the rotational position of the first drum member 21, and has a high roundness encoder scale disk (scale member). SD, and encoder heads EH1, EH2, EH3, EH4, and EH5, which are reading devices. The encoder scale disk SD is fixed to at least one end (both ends in FIG. 16) of the first drum member 21 orthogonal to the rotation axis of the first drum member 21. For this reason, the encoder scale disk SD rotates integrally with the rotation axis ST around the rotation center line AX1. A scale GPM is engraved on the outer peripheral surface of the encoder scale disk SD. The encoder heads EH1, EH2, EH3, EH4, EH5 are arranged around the scale GP when viewed from the rotation axis STM. The encoder heads EH1, EH2, EH3, EH4, and EH5 are arranged to face the scale GPM, and can read the scale GPM without contact. The encoder heads EH1, EH2, EH3, EH4, and EH5 are arranged at different positions in the circumferential direction of the first drum member 21. The first drum member 21 rotates from the encoder head EH4 toward the encoder head EH5.

  The encoder heads EH1, EH2, EH3, EH4, and EH5 are reading devices that have measurement sensitivity (detection sensitivity) with respect to variation in displacement in the tangential direction (in the XZ plane) of the scale GPM. As shown in FIG. 17, when the installation orientations of the encoder heads EH1 and EH2 (angular directions in the XZ plane about the rotation center line AX1) are represented by the installation orientation lines Le11 and Le12, the installation orientation lines Le11 and Le12. However, the encoder heads EH1 and EH2 are arranged so that the angle is ± θ ° with respect to the center plane P3. The installation azimuth lines Le11 and Le12 coincide with the angular directions in the XZ plane about the rotation center line AX1 of the illumination light beam EL1 shown in FIG. Here, the illumination mechanism IU, which is a processing unit, performs a process of transmitting the illumination light beam EL1 to a predetermined pattern (mask pattern) on the cylindrical mask DM, which is an object to be processed. Accordingly, the projection optical system PL can project the image of the pattern in the illumination region IR on the cylindrical mask DM onto a part (projection region PA) of the substrate P being transported by the transport device.

  The encoder head EH4 rotates the installation orientation line Le11 of the encoder head EH1 substantially 90 ° around the axis of the rotation center line AX1 toward the rear side in the rotation direction with respect to the center plane P3 of the first drum member 21. It is set on the line Le14. Further, the encoder head EH5 is installed by rotating the installation azimuth line Le12 of the encoder head EH2 substantially 90 ° around the axis of the rotation center line AX1 toward the rear side in the rotation direction with respect to the center plane P3 of the first drum member 21. It is set on the azimuth line Le15. Here, when substantially 90 ° is 90 ° ± γ, the range of γ is the same as in the above-described embodiment.

  Further, the encoder head EH3 rotates the installation azimuth line Le12 of the encoder head EH2 approximately 120 ° around the axis of the rotation center line AX1, and rotates the encoder head EH4 approximately 120 ° around the axis of the rotation center line AX1. It is set on the line Le13. The arrangement of the encoder heads EH1, EH2, EH3, EH4, and EH5 arranged around the first drum member 21 in the present embodiment is the same as the arrangement of the encoder head EN1 arranged around the second drum member 22 in the embodiment described above. , EN2, EN3, EN4, EN5 in a mirror image-inverted relationship.

  As described above, the exposure device EX1 is a first reading device that reads the second drum member 22 that is a cylindrical member, the scale GP, the projection modules PL1 to PL6 that are processing units of the exposure device EX1, and the scale GP. It has encoder heads EN4 and EN5, and encoder heads EN1 and EN2 that are second reading devices that read the scale GP.

  The first drum member 21 has a curved surface that is curved with a constant radius from the first central axis AX1, which is a predetermined axis, and rotates around the first central axis AX1. The graduations GPM are annularly arranged along the circumferential direction of the first drum member 21 and rotate around the first central axis AX1 together with the first drum member 21. The illumination mechanism IU, which is a processing unit of the exposure apparatus EX1, is disposed inside the first drum member 21 as viewed from the second central axis AX2, and is provided on the substrate P on a curved surface at a specific position in the circumferential direction of the first drum member 21. A process of transmitting the two illumination light fluxes EL1 to (the object to be processed) is performed. The encoder heads EH4 and EH5 are arranged around the scale GPM as viewed from the first central axis AX1, and the specific position described above is rotated by approximately 90 degrees around the first central axis AX1 around the first central axis AX1. It is arranged at a rotated position and reads the scale GPM. The encoder heads EH1 and EH2 read the scale GPM at the specific position described above. The exposure apparatus EX1 corrects an error (pitch error) in the scale GPM provided on the outer peripheral portion of the encoder scale disk SD attached to the first drum member 21 based on the read values of the encoder heads EH4 and EH5. For this reason, the exposure apparatus EX1 can accurately measure the position of the first drum member 21 in the circumferential direction and perform processing on the object to be processed on the curved surface of the second drum member 22, that is, the substrate P. As described above, in the present embodiment, when the error is corrected based on the read values of the encoder heads EH4 and EH5, specifically, the control device 14 of the exposure apparatus EX controls the read value of the encoder head EH4 and the encoder head EH5. The pitch error is corrected based on the difference from the read value. However, when another encoder head is provided around the scale GPM of the first drum member 21 at an installation angle close to either of the encoder heads EH4 and EH5, a direct difference between the two read values of the encoder heads EH4 and EH5 is obtained. Not only the calculation but also the pitch error can be obtained by calculation based on the read values of three encoder heads, namely, the encoder heads EH4 and EH5 and another encoder head. The measurement of the pitch error by the three encoder heads will be described later in detail.

(Second Modification of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 19 is a schematic diagram illustrating an overall configuration of a second modification of the substrate processing apparatus (exposure apparatus). In the exposure apparatus EX2, a light source device (not shown) emits an illumination light beam EL1 illuminated on the cylindrical mask DM. The illumination light beam EL1 emitted from the light source of the light source device is guided to the illumination module IL, and when a plurality of illumination optical systems are provided, the illumination light beam EL1 from the light source is separated into a plurality of illumination light beams and the plurality of illumination light beams EL1 are divided into a plurality of illumination lights. Lead to module IL.

  The illumination light beam EL1 emitted from the light source device enters the polarization beam splitters SP1 and SP2. In the polarization beam splitters SP1 and SP2, in order to suppress energy loss due to the separation of the illumination light beam EL1, it is preferable to make the light beam such that all the incident illumination light beam EL1 is reflected. Here, the polarization beam splitters SP1 and SP2 reflect the luminous flux that becomes S-polarized linearly polarized light and transmit the luminous flux that becomes P-polarized linearly polarized light. Therefore, the light source device emits, to the first drum member 21, the illumination light beam EL1 in which the illumination light beam EL1 incident on the polarization beam splitters SP1 and SP2 is a linearly polarized (S-polarized) light beam. Thus, the light source device emits the illumination light beam EL1 having the same wavelength and phase.

  The polarization beam splitters SP1 and SP2 reflect the illumination light beam EL1 from the light source, while transmitting the projection light beam EL2 reflected by the cylindrical mask DM. In other words, the illumination light beam EL1 from the illumination optical module ILM enters the polarization beam splitters SP1 and SP2 as reflected light beams, and the projection light beam EL2 from the cylindrical mask DM enters the polarization beam splitters SP1 and SP2 as transmitted light beams. .

  As described above, the illumination module IL, which is a processing unit, performs a process of reflecting the illumination light beam EL1 on a predetermined pattern (mask pattern) on the cylindrical mask DM that is an object to be processed. Thereby, the projection optical system PL can project the image of the pattern in the illumination region IR on the cylindrical mask DM onto a part (projection region) of the substrate P being transported by the transport device.

  When a predetermined pattern (mask pattern) for reflecting the illumination light beam EL1 is provided on the curved surface of the cylindrical mask DM, a scale GPm can be provided on the curved surface together with the mask pattern. When the scale GPm is formed simultaneously with the mask pattern, the scale GPm is formed with the same precision as the mask pattern. Therefore, the curved surface detection probes GS1 and GS2 that detect the scale GPm can sample the mark image of the scale GPm at high speed and with high accuracy. At the moment when the sampling is performed, the correspondence between the rotation angle position of the first drum member 21 and the scale GPm is obtained, and the rotation angle position of the first drum member 21 that is sequentially measured can be stored.

  The encoder heads EH4 and EH5 on the side of the cylindrical mask DM read the scale GPm. Then, the exposure apparatus EX2 corrects an error of the scale GPm provided on the surface of the cylindrical mask DM based on the difference between the read values of the encoder heads EH4 and EH5. For this reason, the exposure apparatus EX2 can accurately measure the position of the cylindrical mask DM in the circumferential direction and perform processing on the substrate P on the curved surface of the second drum member 22.

  The encoder heads EN4 and EN5 on the second drum member 22 read the scale GPd of the encoder scale disk SD attached to the second drum member 22. Then, the exposure apparatus EX2 corrects an error of the scale GPd provided on the surface of the encoder scale disk SD based on the difference between the read values of the encoder heads EN4 and EN5. For this reason, the exposure apparatus EX2 can accurately measure the position of the second drum member 22 in the circumferential direction and perform processing on the substrate P on the curved surface of the second drum member 22.

(Third Modification of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 20 is a schematic diagram illustrating an overall configuration of a third modification of the substrate processing apparatus (exposure apparatus). The exposure apparatus EX3 includes polygon scanning units PO1 and PO2 that receive an exposure beam from a light source device (not shown). The polygon scanning unit PO emits spot light whose intensity is modulated along a one-dimensional scanning line on the substrate P. Scan. The exposure apparatus EX3 included in the substrate processing apparatus can draw a predetermined pattern by irradiating the substrate P at a specific position with exposure light without the cylindrical mask DM.

  The encoder heads EN4 and EN5 on the second drum member 22 side of the exposure apparatus EX3 read the scale GPd of the encoder scale disk SD attached to the second drum member 22. Then, the exposure apparatus EX2 corrects an error of the scale GPd provided on the surface of the encoder scale disk SD based on the difference between the read values of the encoder heads EN4 and EN5. For this reason, the exposure apparatus EX2 can accurately measure the position of the second drum member 22 in the circumferential direction and perform processing on the substrate P on the curved surface of the second drum member 22.

  As shown in FIG. 20 (and FIG. 19), the encoder heads EN4 and EN5 on the second drum member 22 side are arranged corresponding to each of the two rows of alignment microscopes AMG1 and AMG2 in the circumferential direction. Was done. However, among the alignment microscopes AMG1 and AMG2, for example, only the alignment microscope AMG2 (and the corresponding encoder head EN5) may be disposed. Even in such a case, it is preferable to provide the encoder head EN4. When only the alignment microscope AMG2 (and the corresponding encoder head EN5) is arranged and the encoder head EN4 cannot be installed in the vicinity of the alignment microscope AMG2 at the rotation angle α, the scale is adjusted by using the encoder heads EN1 and EN2 arranged corresponding to the exposure position. An error map such as pitch error or eccentricity of the scale GPd of the disk SD may be created.

  Further, at least one error map such as pitch error and eccentricity of the scale GPd obtained by using the two encoder heads EN4 and EN5, and pitch error and eccentricity of the scale GPd obtained by using the two encoder heads EN1 and EN2. By comparing with at least one error map, it is verified whether there is a large difference between both error maps, and if there is a difference exceeding the allowable value, re-create the error map again , The accuracy and reliability of the error map can be improved.

(Fourth Modified Example of Substrate Processing Apparatus (Exposure Apparatus))
FIG. 21 is a schematic diagram illustrating an overall configuration of a fourth modification of the substrate processing apparatus (exposure apparatus). The exposure apparatus EX4 is a substrate processing apparatus that performs so-called proximity exposure on the substrate P. The exposure apparatus EX4 sets the gap between the cylindrical mask DM and the second drum member 22 to be small, and the illumination mechanism IU directly irradiates the substrate P with the illumination light beam EL1 to perform non-contact exposure. In the present embodiment, the second drum member 22 is rotated by a torque supplied from a second driving unit 36 including an actuator such as an electric motor. The drive roller MGG connected by, for example, a magnetic gear drives the first drum member 21 so that the rotation direction is opposite to the rotation direction of the second drive unit 36. The second driving unit 36 rotates the second drum member 22 and also rotates the driving roller MGG and the first drum member 21 to synchronize the first drum member 21 (cylindrical mask DM) and the second drum member 22. Move (synchronous rotation).

  The exposure apparatus EX4 includes an encoder head EN6 that detects a position PX6 of a graduation GP at a specific position where the principal ray of the imaging light beam EL2 enters the substrate P with respect to the substrate P. Here, since the diameter of the outer peripheral surface of the outer peripheral surface of the second drum member 22 around which the substrate P is wound is equal to the diameter of the scale GP of the encoder scale disk SD, the position PX6 is located from the second central axis AX2. It matches the specific position described above. Then, the encoder head EN7 is set on the installation azimuth line Le7, which is substantially 90 ° rotated about the installation azimuth line Le6 of the encoder head EN6 around the axis of the rotation center line AX2 toward the rear side in the feed direction of the substrate P. .

  The exposure apparatus EX4 uses, for example, the encoder head EN3 as a first reading unit and the encoder head EN7 as a second reading unit. The encoder heads EN3 and EN7 read the scale GPd of the encoder scale disk SD attached to the second drum member 22. The control device 14 corrects an error of the scale GPd provided on the surface of the encoder scale disk SD based on the difference between the read values of the encoder heads EN3 and EN7. For this reason, the exposure apparatus EX4 can accurately measure the position of the second drum member 22 in the circumferential direction and perform processing on the substrate P on the curved surface of the second drum member 22. The encoder heads EN3 and EN7 are formed by an encoder formed by a line connecting the encoder head EN3 and the second center axis AX2 (installation azimuth line Le3) and a line connecting the encoder head EN7 and the second center axis AX2 (installation azimuth line Le7). The mounting angle θs may be less than 90 degrees, preferably 45 degrees or less.

  The first to fourth modifications of the above-described embodiment and the substrate processing apparatus (exposure apparatus) exemplify the exposure apparatus as the substrate processing apparatus. The substrate processing apparatus is not limited to an exposure apparatus, but may be an apparatus in which a processing unit prints a pattern on a substrate P, which is an object to be processed, using an inkjet ink dropping apparatus. Further, the processing unit may be an inspection device.

  By the way, in the description of the reading operation of the graduation GP by the encoder heads EN4 and EN5 with reference to FIGS. 7 and 8, the up pulse U is output when the rising portion GPa of one graduation of the graduation GP is read. When the falling part GPb is read, a down pulse D is output, and the interval between two adjacent rising parts GPa or the interval between adjacent falling parts GPb is defined as the pitch SS of the scale GP. However, an actual encoder measurement system includes a two-phase signal (a sine wave having a phase difference of 90 degrees) output from a signal generation unit (encoder head) as disclosed in, for example, JP-A-9-196702. Signal and cosine wave signal) by means of an interpolation circuit, a comparator, etc., to generate an up pulse U and a down pulse D at intervals obtained by subdividing the actual pitch SS of the graduation GP into several tenths to several tenths. It is configured as follows.

  FIG. 22 briefly describes the actual reading operation of the graduation GP (GPd, GPM) by the encoder heads EN1 to EN7 and EH1 to EH5 shown in FIGS. 4 to 6, FIG. 10 and FIGS. FIG. 4 is a signal waveform diagram for the present invention. As shown in FIG. 22, each of encoder heads EN1 to EN7 and EH1 to EH5 outputs two measurement signals EcA and EcB having a phase difference of 90 degrees (represented here by rectangular waves). One cycle of the measurement signals EcA and EcB corresponds to 1 / n of the pitch SS of the scale GP. n (integer) differs depending on the optical reading mode in the encoder head, but is set to any value of a multiple series such as 1, 2, 4, 8,. In a normal encoder measurement system, while the scale disk SD is rotating in the forward direction and the scale GP is always moving in one direction with respect to the encoder head, the scaled-up data interpolated based on the measurement signals EcA and EcB. The pulse signal EcU continues to be generated. When the scale disk SD is reversed, the interpolated down pulse signal based on the measurement signals EcA and EcB continues to be generated from that point.

  In FIG. 22, a processing circuit that transmits an up pulse signal EcU (or a down pulse signal EcD) that generates a pulse at intervals obtained by dividing one cycle of the measurement signals EcA and EcB into eight is used. The up-down counter as a counter sequentially counts up the number of pulses when the up-pulse signal EcU is input, and sequentially counts down the number of pulses when the down-pulse signal EcD is input. Here, for example, assuming that one cycle of the measurement signals EcA and EcB corresponds to １ ／ of the actual pitch SS of the scale GP, the up-down counter determines that the scale surface of the scale disk SD (scale GP) is in order. While moving in the direction by one pitch SS, 64 pulses of the up pulse signal EcU are counted. Therefore, when the pitch SS of the scale GP is 20 μm, the increment of the count value for one pitch by the up / down counter is 64, and the measurement resolution (movement amount per signal EcU pulse) of the encoder measurement system is 0. .3125 μm (20 μm / 64). As described above, the measurement resolution as the encoder measurement system is refined by interpolating the actual size of the pitch SS of the scale GP to several tenths to several tenths. It is obtained with an accuracy corresponding to the degree of the interpolation.

  When the circumference length (diameter × π) of the scale surface of the scale disk SD is divided by a finite number of graduations (the number of grids), the actual size of the pitch SS of the actual graduation GP is a fraction of 20 μm. May be accompanied. On the other hand, the pitch SS is set so that the measurement resolution becomes a sharp value (for example, 0.25 μm), and the circumferential length of the scale surface of the scale disk SD is divisible within the predetermined accuracy by the pitch SS. Alternatively, the diameter of the scale surface may be set.

  By the way, on the scale surface of the scale disk SD or the like, an origin mark serving as the origin of one rotation of the scale disk SD is engraved together with the scale GP, and each of the encoder heads EN1 to EN7 detects the origin mark. At that moment, an origin signal (pulse) EcZ is output. The up-down counter resets the count value to zero in response to the origin signal EcZ, and then continues counting the number of pulses of the up-pulse signal EcU (or the down-pulse signal EcD) again. Therefore, each of the up / down counters provided corresponding to each of the encoder heads EN1 to EN7 has a pulse of the up pulse signal EcU (or the down pulse signal EcD) with the moment when the origin signal EcZ is received as a reference (zero point). Numbers are added (or subtracted).

  From the above, for example, when calculating the pitch error of the scale GP based on the difference between the measurement values of the encoder head EN4 and the encoder head EN5, the scale disk SD (the second drum member 22) is used in FIGS. As described above, every time the motor rotates by the angle α, it is only necessary to digitally calculate the difference between the count value of the up / down counter corresponding to the encoder head EN4 and the count value of the up / down counter corresponding to the encoder head EN5. Good. The angle α increases the count value of the up / down counter corresponding to one of the encoder heads EN4 and EN5 (or may be another encoder head) by a constant value corresponding to the angle α. It can be detected by determining whether (or decreased).

(Modification 1)
In the above embodiments and modifications, the scale GP configuring the encoder measurement system is engraved on at least one of the cylindrical outer peripheral surfaces of the scale disk SD as the rotating body and the second drum member 22. However, the scale GP may be formed at a predetermined pitch along the circumferential direction on a side end surface perpendicular to the rotation center line AX2 of at least one of the scale disk SD and the second drum member 22. FIG. 23 is a diagram showing the configuration in which the scale GP is formed on the side end surface of the scale disk SD as seen from the direction (Y-axis direction) in which the rotation center line AX2 extends as in FIG. FIG. 24 is a cross-sectional view taken along the line AA ′ of the configuration of FIG. 23 cut along a plane including the installation orientation line Le4 and the rotation center line AX2.

  In FIG. 23, ring-shaped scale disks SD are attached to eight side end surfaces of the second drum member 22 with adjusting members (screw) 60. The mounting angle β of the adjusting member (screw) 60 is 45 ° here. On a side surface parallel to the XZ plane of the scale disk SD, a scale GP having a constant pitch SS and an origin mark Zs are formed along a circumference having a radius ra from the rotation center line AX2. As shown in FIG. 24, the encoder heads EN4 and EN5 are arranged in the Y-axis direction so as to face the scale GP with a certain gap. As shown in FIG. 23, the reading position RP4 of the encoder head EN4 is set on the radius ra and on the installation azimuth line Le4. The reading position RP5 of the encoder head EN5 is set on the radius ra and on the installation azimuth line Le5. The radius ra is the radius of the outer peripheral surface 22s of the second drum member 22, which closely supports the substrate P, as shown in FIG. Therefore, the maximum diameter of the ring-shaped scale disk SD is set slightly larger than the radius ra. In this way, by arranging the scale disk SD and the encoder heads EN4 and EN5, Abbe error during measurement can be minimized. Other encoder heads (EN1 to EN3, EN6 to EN7) for the ring-shaped scale disk SD shown in FIGS. 23 and 24 are also arranged so as to satisfy the Abbe conditions for measurement, similarly to the heads EN4 and EN5.

(Modification 2)
In the above-described embodiments and modified examples, in order to measure the pitch error of the scale GP, the difference between the measured values of the two encoder heads (for example, the encoder heads EN4 and EN5) arranged close to each other is calculated by using the scale disk. Each time the SD (the second drum member 22) rotates by the angle α (α <θs), it is stored to create a map relating to the pitch error of the entire circumference of the scale disk SD. In this case, in order to increase the accuracy of the map, the angle θs formed by the reading positions (corresponding to RP4 and RP5 in FIG. 23) on each scale surface of the two encoder heads (for example, the encoder heads EN4 and EN5) is determined. It is preferable to make it as small as possible. However, the angle θs may not be sufficiently small depending on the outer shapes and dimensions of the encoder heads EN4 and EN5 or the angles between the installation azimuth lines Le4 and Le5 determined by the arrangement of the alignment microscopes AMG1 and AMG2.

  Therefore, in the second modification, for example, three or more encoder heads EN1 (or EN2) arranged near the two encoder heads EN4 and EN5 used for the pitch error measurement in the previous embodiment are added. The pitch error map is further refined using the measurements from each of the encoder heads. FIG. 25 is a diagram showing the arrangement of the scale disk SD (here, ring-shaped) and the encoder heads EN1, EN2, EN4, and EN5 in the XZ plane, as in FIG. Scale GP and origin mark Zs are formed along the outer peripheral surface of SD. Further, it is assumed that the scale disk SD is fixed to the side end surface of the second drum member 22 by adjusting members (screw) 60 at 16 locations in the circumferential direction. Therefore, the mounting angle β of the adjusting member (screw) 60 is 22.5 °.

  As shown in FIG. 25, the encoder head EN1 whose reading position is set on the installation azimuth line Le1 corresponding to the odd-numbered exposure position, and the reading position is set on the installation azimuth line Le2 corresponding to the even-numbered exposure position. The set encoder head EN2 is disposed at an angle ± θ with respect to the center plane P3 in the XZ plane. The angles θs formed by the installation azimuth lines Le4 and Le5 passing through the reading positions of the encoder heads EN4 and EN5 have a relationship of θs> β. Further, an angle between the installation azimuth line Le1 passing through the reading position of the encoder head EN1 and the installation azimuth line Le4 passing through the reading position of the encoder head EN4 is defined as θq. Also, the count values of the up / down counters provided for each of the encoder heads EN1, EN2, EN4, and EN5 are Cm1, Cm2, Cm4, and Cm5, respectively.

  When the scale disk SD (the second drum member 22) shown in FIG. 25 rotates clockwise in the XZ plane, the origin mark Zs formed on the scale surface of the scale disk SD corresponds to the encoder heads EN4, EN5, and EN1. , EN2 in the order of the reading positions. Accordingly, the moment the origin mark Zs crosses the reading position of the encoder head EN4, the count value Cm4 of the corresponding up / down counter is reset to zero, and the moment the origin mark Zs crosses the reading position of the encoder head EN5. When the count value Cm5 of the up / down counter is reset to zero and the origin mark Zs crosses the reading position of the encoder head EN1, the count value Cm1 of the corresponding up / down counter is reset to zero and the origin mark Zs is set to the encoder head EN2. At the moment of crossing the reading position, the count value Cm2 of the corresponding up / down counter is reset to zero. When the scale disk SD rotates clockwise, the count values Cm1, Cm2, Cm4, and Cm5 after all the four up / down counters are reset to zero always have the relationship of Cm2 <Cm1 <Cm5 <Cm4. I have.

Therefore, when a pitch error is obtained using the three encoder heads EN1 (count value Cm1), EN4 (count value Cm4), and EN5 (count value Cm5) to create an error map (correction map), a scale disk is used. Each time the SD (second drum member 22) rotates by a certain angle α (α <β <θs), a measurement value ΔMs related to the pitch error for each unit angle α is obtained by the following equation (1). This measurement value ΔMs corresponds to the number NS of the scales GP shown in FIG. 11 described above, but is actually a count value of the up pulse (or down pulse) EcU shown in FIG. .
ΔMs = (Cm4 + Cm1) / 2−Cm5 Equation (1)

  In the equation (1), the calculated value of (Cm4 + Cm1) / 2 is set to an angular position that is an intermediate point between the reading position RP4 of the encoder head EN4 and the reading position RP1 of the encoder head EN1, as shown in FIG. Represents the count value expected to be obtained when the reading position RPi of the encoder head is set to the virtual installation azimuth line Lei. Therefore, the measurement value ΔMs obtained by the expression (1) or (2) described later is calculated by the count value Cmi (calculated value) at the reading position RPi by the virtual encoder head and the reading position RP5 of the encoder head EN5. Is the difference from the count value Cm5. By obtaining the measured value ΔMs by 360 degrees for each unit angle α, a pitch error map or a pitch error correction map of a scale (scale GP) such as the scale disk SD can be created.

  By the way, in the case of the arrangement shown in FIG. 25, during the period in which the origin mark Zs passes between the reading position RP4 of the encoder head EN4 and the reading position RP1 of the encoder head EN1, the count value Cm4 and the measurement value Cm5 Has been reset to zero, the continuity of the three count values Cm1, Cm4 and Cm5 may not be ensured. In that period, the magnitude relationship between the count values Cm1, Cm4, and Cm5 (absolute values) is Cm4 <Cm1 <Cm5 or Cm5 <Cm4 <Cm1. Therefore, the maximum count value (fixed value) counted by the up / down counter from the time of zero reset to the time of the next zero reset is defined as Cmf, and each encoder head EN1, EN4, EN5 is provided for each angle α. When reading the count values Cm1, Cm4, and Cm5, when the origin mark Zs is between the read position RP4 of the encoder head EN4 and the read position RP5 of the encoder head EN5, the count value Cm4 of the up / down counter is the maximum count value. A new count value Cm4 ′ to which Cmf has been added may be used instead of the count value Cm4 in the equation (1). Similarly, when the origin mark Zs is between the reading position RP5 of the encoder head EN5 and the reading position RP1 of the encoder head EN1, a new value obtained by adding the maximum count value Cmf to each of the count values Cm4 and Cm5 of the up / down counter. The simple count values Cm4 ′ and Cm5 ′ may be used instead of the count values Cm4 and Cm5 in the equation (1).

  In the case of the second modification, the first reading unit includes two encoder heads EN1 and EN4 (or one encoder head EN5), and the second reading unit includes one encoder head EN5 (or two encoder heads). EN1 and EN4). In the above configuration, if the angle θs and the angle θq are set to an appropriate relationship, the angle formed by the virtual reading position RPi and the reading position RP5 is determined by the mounting angle β of the adjustment member (screw) 60 (22. 5 °), and a pitch error (pitch unevenness) due to slight deformation of the scale surface of the scale disk SD remaining after adjustment of the roundness, eccentricity, and the like by the adjustment member 60 is performed in a span equal to or less than the angle β. It can be measured in detail.

In the method of setting the virtual reading position RPi on the scale surface as described above, for example, the virtual reading position RPi is set at the intermediate point between the reading positions RP4 and RP1 of the two encoder heads EN4 and EN1 shown in FIG. The calculated count value obtained at the virtual first reading position RPi and the virtual second reading position RPi set at the intermediate point between the reading positions RP5 and RP2 of the two encoder heads EN5 and EN2. The pitch error may be obtained from the difference from the calculated count value. In this case, the measurement value ΔMs for each unit angle α is calculated by the following equation (2).
ΔMs = (Cm4 + Cm1) / 2− (Cm5 + Cm2) / 2 Expression (2)

(Device manufacturing method)
FIG. 26 is a flowchart illustrating a procedure of a device manufacturing method for manufacturing a device using the substrate processing apparatus (exposure apparatus) according to the embodiment. In this device manufacturing method, first, the function and performance of a display panel are designed using self-luminous elements such as an organic EL, and necessary circuit patterns and wiring patterns are designed by CAD or the like (step S201). Next, a cylindrical mask DM for a necessary layer is manufactured based on a pattern for each layer designed by CAD or the like (step S202). Further, a supply roll FR1 around which a flexible substrate P (resin film, metal foil film, plastic, or the like) serving as a base material of the display panel is wound is prepared (Step S203). The roll-shaped substrate P prepared in step S203 has a surface modified as necessary, a base layer (for example, fine irregularities formed by an imprint method) previously formed, A functional film or a transparent film (insulating material) laminated in advance may be used.

  Next, a backplane layer composed of electrodes, wirings, insulating films, TFTs (thin film semiconductors) and the like constituting the display panel device is formed on the substrate P, and an organic EL or the like is laminated on the backplane. A light emitting layer (display pixel portion) is formed by the self light emitting element (step S204). This step S204 includes a conventional photolithography step of exposing a photoresist layer using the exposure apparatus EX, EX2, EX3, EX4 described in each of the above embodiments. An exposure step of pattern-exposing the substrate P coated with the silane coupling material to form a water-repellent pattern on the surface, pattern-exposing the photosensitive catalyst layer, and electroless plating to form a metal film pattern (wiring, electrode And the like, and a printing process of drawing a pattern with a conductive ink containing silver nanoparticles or the like.

  Next, for each display panel device continuously manufactured on the long substrate P by a roll method, the substrate P is diced, or a protective film (for environmental barrier layer) or a color filter is formed on the surface of each display panel device. The device is assembled by bonding sheets or the like (step S205). Next, an inspection process is performed to determine whether the display panel device functions normally or satisfies desired performance and characteristics (step S206). As described above, a display panel (flexible display) can be manufactured.

  In the above embodiment, a light-transmitting reticle in which a predetermined light-shielding pattern (or a phase pattern or a dimming pattern) is formed on a light-transmitting substrate is used, but instead of this reticle, for example, US Pat. No. 6,778,257 As described in the specification, a variable-shaped reticle that forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed (also referred to as an electronic reticle, an active reticle, or an image generator). May be used. Further, a pattern forming apparatus including a self-luminous image display element may be provided instead of the variable-shaped reticle including the non-luminous image display element.

  Further, the exposure apparatus of the above embodiment is manufactured by assembling various subsystems including the respective components recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Is done. Before and after assembling the exposure apparatus, adjustments to achieve optical accuracy for various optical systems, adjustments to achieve mechanical accuracy for various mechanical systems, and various electrical Adjustments are made to the system to achieve electrical accuracy. The process of assembling an exposure apparatus by combining various subsystems includes mechanical connection between various subsystems, wiring connection of an electric circuit, and piping connection of a pneumatic circuit. It goes without saying that there is an assembling process for each subsystem before the assembling process from the various subsystems to the exposure apparatus. When the process of assembling the various subsystems into the exposure apparatus is completed, comprehensive adjustment is performed, and various precisions of the entire exposure apparatus are secured. It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature, cleanliness, and the like are controlled.

  Also, the components of the above embodiment can be appropriately combined. In some cases, some components may not be used. Further, the components can be replaced or changed without departing from the spirit of the present invention. In addition, to the extent permitted by law, the disclosures of all the publications and U.S. patents relating to the exposure apparatus and the like cited in the above embodiments are incorporated herein by reference. As described above, other embodiments, operation techniques, and the like performed by those skilled in the art based on the above embodiments are all included in the scope of the present invention.

Reference Signs List 11 substrate processing device 14 control device 21 first drum member 22 second drum member 25 first detector 35 second detector 60 adjusting member 61 male screw part 62 head part AX1 rotation center line (first center axis)
AX2 rotation center line (second center axis)
Cs Roundness adjusting mechanism DM Cylindrical mask EN, EN1, EN2, EN3, EN4, EN5, EH1, EH2, EH3, EH4, EH5 Encoder head EX, EX1, EX2, EX3, EX4 Exposure devices GP, GPd, GPM, GPm Scale NS Number of measurement scales P Substrate SD Encoder scale disk TBc Correction map

Claims (7)

A substrate processing apparatus that transports a long sheet substrate having flexibility in a long direction and performs a predetermined process on the sheet substrate,
A rotary drum that supports the sheet substrate on an outer peripheral surface that is cylindrically curved with a constant radius from a center line, and rotates around the center line to convey the sheet substrate in a longitudinal direction,
A processing unit that performs processing on the sheet substrate at a specific position within a circumferential direction of the sheet substrate supported by an outer peripheral surface of the rotating drum,
A scale is provided annularly along the circumferential direction in which the rotating drum rotates, rotates around the center line together with the rotating drum, and measures the position change in the circumferential direction of the sheet substrate by encoder measurement.
A first encoder head that is arranged in a first direction in a circumferential direction so as to face the scale scale and reads the scale scale;
A second encoder head that is arranged in a second direction rotated in the circumferential direction by an angle θq with respect to the first direction to face the scale scale, and reads the scale scale;
A third azimuth between the first azimuth and the second azimuth with respect to the circumferential direction and rotated by an angle θs in the circumferential direction with respect to the second azimuth so as to face the scale graduation. A third encoder head arranged to read the scale mark;
When the first read value by the first encoder head is Cm1, the second read value by the second encoder head is Cm4, and the third read value by the third encoder head is Cm5, ΔMs = (Cm1 + Cm4) / 2− A storage unit for sequentially storing the measurement value ΔMs calculated by Cm5 for each rotation of the scale graduation at a fixed angle α, and storing error information relating to a pitch error over the entire circumference of the scale graduation ,
With respect to the circumferential direction of movement of the scale scale accompanying the rotation of the rotary drum, the second encoder head, the third encoder head, and the first encoder head are arranged in this order from the upstream side, and the fixed angle α and the A substrate processing apparatus , wherein an angle θs is set in a relation of α <θs . The substrate processing apparatus according to claim 1 ,
The angle θs is set within 45 degrees,
The constant angle α is set to one of a value other than a divisor of 360 degrees, a value that is a prime number with respect to 360 degrees, and a value that can be divided by one to four digits after the decimal point. ,
Substrate processing equipment. The substrate processing apparatus according to claim 1 or 2 ,
The first azimuth where the first encoder head is arranged is set to be the same as the azimuth in the circumferential direction of the specific position to be processed by the processing unit,
When performing processing on the sheet substrate by the processing unit, the first read value by the first encoder head, the value corrected based on the error information stored in the storage unit, the value of the sheet substrate A substrate processing apparatus further comprising a correction unit that outputs a transfer position or a transfer amount in a long direction. The substrate processing apparatus according to any one of claims 1 to 3,
The scale is fixed coaxially with the center line at at least one end of the rotating drum in a direction in which the center line extends, on an outer peripheral portion parallel to the center line of the scale disk that rotates with the rotating drum. Engraved,
Substrate processing equipment. The substrate processing apparatus according to claim 4 , wherein
In order to fix the scale disk to the end of the rotating drum, a plurality of fastening members are provided at predetermined attachment angles β along the circumferential direction of the scale disk,
The attachment angle β, the fixed angle α, and the angle θs are set in a relationship of α <β <θs.
Substrate processing equipment. The substrate processing apparatus according to claim 1 or 2,
The scale graduation includes an origin mark provided at one place of the entire circumference,
A first counter that outputs the first read value Cm1 and resets the first read value Cm1 to zero at the moment when the first encoder head detects the origin mark;
A second counter that outputs the second read value Cm4 and resets the second read value Cm4 to zero at the moment when the second encoder head detects the origin mark;
A third counter that outputs the third read value Cm5 and resets the third read value Cm5 to zero at the moment when the third encoder head detects the origin mark.
Substrate processing equipment. The substrate processing apparatus according to claim 6 ,
When the maximum count value counted by each of the three counters during one rotation of the scale is Cmf,
When the origin mark is located between the reading position of the second encoder head and the reading position of the third encoder head, the maximum count value Cmf is added to the second read value Cm4 output by the second counter. Using the added count value Cm4 ′, the measurement value ΔMs is calculated as ΔMs = (Cm1 + Cm4 ′) / 2−Cm5,
When the origin mark is between the reading position of the third encoder head and the reading position of the first encoder head, the maximum reading Cmf is added to the third reading Cm5 output by the third counter. Using the added count value Cm5 ′ and the count value Cm4 ′, the measurement value ΔMs is calculated as ΔMs = (Cm1 + Cm4 ′) / 2−Cm5 ′.
Substrate processing equipment.

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