JP4717782B2 - Substrate processing equipment - Google Patents

Description

  The present invention relates to a technique for controlling discharge of a processing liquid in a slit coater. More specifically, the present invention relates to a measurement technique for performing accurate control.

  There is a coating apparatus for applying a processing liquid such as a photoresist onto the surface of a glass square substrate for liquid crystal, a semiconductor wafer, a flexible substrate for film liquid crystal, a substrate for photomask, a substrate for color filter, etc. (hereinafter simply referred to as “substrate”). Are known. For example, as a coating apparatus, there is a slit coater that performs slit coating using a slit nozzle having a slit-like discharge portion. In a slit coater, variation in coating film thickness (coating unevenness) causes a change in wiring width, and thus control of coating film thickness (uniformity) is a particularly important factor.

  The slit coater discharges resist from the slit nozzle and simultaneously moves the slit nozzle at a constant speed to form a uniform film thickness. It is the most difficult to control the film thickness. In particular, at the coating start position, the unstable region of the film thickness decreases as the slit nozzle movement acceleration time and the discharge flow rate acceleration time are shorter.

  The general coating speed of the slit coater is about 200 mm / second, and in order to keep the unstable region at the coating start position within 10 mm, the movement acceleration time is required to be completed within about 0.025 seconds. . On the other hand, since the applied film thickness is greatly affected by the discharge flow rate from the slit nozzle, it is required to accurately measure the discharge flow rate for film thickness control. However, a flow meter that directly measures the discharge flow rate is unsuitable for short-time measurement (cannot be measured accurately), and it is virtually impossible to measure an accurate value in such a short time.

  Therefore, conventionally, a method for observing the discharge state using a pressure sensor has been proposed. For example, this technique is described in Patent Document 1. Patent Document 1 proposes a technique in which one pressure sensor is provided on the primary side of the slit nozzle (between the discharge pump and the slit nozzle), and the discharge is controlled based on the pressure of the processing liquid measured by the pressure sensor. ing.

JP 2003-181360 A

  In the technique described in Patent Document 1, the pressure sensor is provided on the primary side of the slit nozzle.

  FIG. 11 is a diagram showing measured values of the pressure sensor provided on the primary side of the slit nozzle when the structure of the supply channel (pipe diameter, length, pipe arrangement, etc.) is variously changed. As shown in FIG. 11, the measurement value of the pressure sensor provided on the primary side of the slit nozzle varies depending on the structure of the supply path. This means that when the pressure sensor is provided on the primary side of the slit nozzle, the pressure loss from the discharge pump to the slit nozzle greatly affects the measured value.

  In other words, the pressure sensor described in Patent Document 1 does not measure the pressure applied to the slit nozzle (it cannot accurately measure the state of the processing liquid actually discharged from the slit nozzle). there were. Therefore, the pressure measured by such a pressure sensor is a numerical value affected by the first-order lag, and there is a problem that the calculation must be performed in consideration of this lag when used for actual control. .

  The present invention has been made in view of the above problems, and an object thereof is to accurately measure the state of a processing liquid discharged from a slit nozzle.

  In order to solve the above problems, the invention of claim 1 is a substrate processing apparatus for applying a processing liquid to a substrate, wherein a processing liquid flow path is provided therein, and a slit-like discharge port is provided from the flow path. A slit nozzle that discharges the processing liquid through the substrate, a moving unit that relatively moves the substrate to which the processing liquid is applied and the slit nozzle, and the flow path in the slit nozzle through the first flow path of the processing liquid. A liquid supply means for supplying the processing liquid to the first flow path; a second flow path for the processing liquid that is provided independently of the first flow path and communicates directly with the flow path in the slit nozzle; and the second flow path And a movement control means for controlling the moving means based on a measurement result of the pressure measuring means.

  Further, the invention of claim 2 is the substrate processing apparatus according to the invention of claim 1, further comprising a preliminary application unit for applying a processing liquid prior to processing on the substrate, wherein the movement control means includes the preliminary processing unit. The moving means for applying the treatment liquid to the substrate is controlled based on the measurement result of the pressure measurement means for applying the treatment liquid to the application portion.

  Further, the invention of claim 3 is the substrate processing apparatus according to the invention of claim 2, in which the liquid feeding pressure measuring means for measuring the pressure of the processing liquid fed by the liquid feeding means, and the preliminary coating section The liquid supply control means further controls the liquid supply means when applying the treatment liquid to the substrate based on the measurement result of the liquid supply pressure measurement means when applying the treatment liquid.

  The invention of claim 4 is the substrate processing apparatus according to any one of claims 1 to 3, wherein the second flow path is a pipe for extracting air from the inside of the slit nozzle. It is characterized by.

  In the invention according to any one of claims 1 to 4, a liquid feeding means for feeding the processing liquid to the flow path in the slit nozzle via the first flow path of the processing liquid, and the first flow path are provided independently. A second flow path of the processing liquid directly communicating with the flow path in the slit nozzle, a pressure measuring means installed in the second flow path, and a movement control means for controlling the moving means based on the measurement result of the pressure measuring means; With this, it is possible to accurately measure the discharge state of the processing liquid. Therefore, the moving means can be accurately controlled.

  According to the second aspect of the present invention, the apparatus further includes a preliminary application unit that applies the processing liquid prior to the processing on the substrate, and the movement control unit is a measurement result of the pressure measurement unit when the processing liquid is applied to the preliminary application unit. On the basis of the above, by controlling the moving means when applying the processing liquid to the substrate, it is not necessary to measure each time every application processing, and the amount of calculation processing can be suppressed.

  In the invention according to claim 3, the measurement result of the liquid-feeding pressure measuring means for measuring the pressure of the processing liquid fed by the liquid-feeding means and the liquid-feeding pressure measuring means when applying the processing liquid to the preliminary coating portion Based on the above, the liquid supply means can be accurately controlled by further including the liquid supply control means for controlling the liquid supply means when applying the processing liquid to the substrate. Therefore, the accuracy in the coating process is further improved.

  In the invention according to claim 4, the second flow path is a pipe for extracting air from the inside of the slit nozzle, so that the second flow path can also be used as an air bleeding pipe, and a flow path for attaching pressure measuring means. Need not be provided separately.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

<1. First Embodiment>
FIG. 1 is a perspective view schematically showing a substrate processing apparatus 1 according to the present invention. FIG. 2 is a view showing a side cross section of the main body 2 of the substrate processing apparatus 1 and showing main components related to the application operation of the resist solution.

  In FIG. 1, for the sake of illustration and explanation, the Z-axis direction is defined as the vertical direction and the XY plane is defined as the horizontal plane, but these are defined for convenience in order to grasp the positional relationship. The directions described below are not limited. The same applies to the following figures.

  The substrate processing apparatus 1 is roughly divided into a main body 2 and a control unit 8, and a square glass substrate for manufacturing a screen panel of a liquid crystal display device is a substrate to be processed (hereinafter simply referred to as “substrate”) 90. In the process of selectively etching an electrode layer or the like formed on the surface of the substrate 90, the coating device is configured to apply a resist solution as a processing solution to the surface of the substrate 90. Therefore, in this embodiment, the slit nozzle 41 discharges the resist solution. In addition, the substrate processing apparatus 1 can be modified and used not only as a glass substrate for a liquid crystal display device but also as a device for applying a processing liquid to various substrates for a flat panel display.

  The main body 2 includes a stage 3 that functions as a holding table for mounting and holding the substrate 90 and also functions as a base for each attached mechanism. The stage 3 is made of, for example, an integral stone having a rectangular parallelepiped shape, and its upper surface (holding surface 30) and side surfaces are processed into flat surfaces.

  The upper surface of the stage 3 is a horizontal plane and serves as a holding surface 30 for the substrate 90. A number of vacuum suction ports (not shown) are formed on the holding surface 30 in a distributed manner, and the substrate 90 is held in a predetermined horizontal position by sucking the substrate 90 while the substrate processing apparatus 1 processes the substrate 90. To do. The holding surface 30 is provided with a plurality of lift pins LP that can be moved up and down by driving means (not shown) at appropriate intervals. The lift pins LP are used to push up the substrate 90 when the substrate 90 is removed.

  A pair of running rails 31 extending in parallel in a substantially horizontal direction are fixed to both ends of the holding surface 30 across the holding area of the substrate 90 (region where the substrate 90 is held). The traveling rail 31 guides the movement of the bridging structure 4 together with a support block (not shown) fixed at the lowermost part of both ends of the bridging structure 4 (the moving direction is defined in a predetermined direction), and holds the bridging structure 4. A linear guide supported above the surface 30 is configured.

  Above the stage 3, a bridging structure 4 is provided that extends substantially horizontally from both sides of the stage 3. The bridging structure 4 is mainly composed of, for example, a nozzle support portion 40 that uses carbon fiber reinforced resin as an aggregate, and elevating mechanisms 43 and 44 that support both ends thereof.

  A slit nozzle 41 is attached to the nozzle support portion 40. In FIG. 1, a resist supply mechanism 6 (FIG. 2) for supplying a resist solution to the slit nozzle 41 is connected to a slit nozzle 41 having a longitudinal direction in the Y-axis direction. Details of the slit nozzle 41 and the resist supply mechanism 6 will be described later.

  The elevating mechanisms 43 and 44 are divided on both sides of the slit nozzle 41 and connected to the slit nozzle 41 by the nozzle support portion 40. The elevating mechanisms 43 and 44 are mainly composed of AC servomotors 43 a and 44 a and a ball screw (not shown), and generate elevating driving force for the bridging structure 4 based on a control signal from the control unit 8. Thereby, the raising / lowering mechanisms 43 and 44 raise / lower the slit nozzle 41 in translation. The lifting mechanisms 43 and 44 are also used to adjust the posture of the slit nozzle 41 in the YZ plane.

  A pair of AC coreless linear motors (hereinafter simply referred to as “stator”) and a “moving element 50b” and “stator 51a” and “moving element 51b” are provided at both ends of the bridging structure 4 along the edges on both sides of the stage 3, respectively. , Abbreviated as “linear motor”.) 50 and 51 are fixed. In addition, linear encoders 52 and 53 each having a scale portion and a detector are fixed to both ends of the bridging structure 4. The linear encoders 52 and 53 detect the positions of the linear motors 50 and 51.

  The linear motors 50 and 51 and the linear encoders 52 and 53 mainly constitute the traveling mechanism 5 for moving the bridge structure 4 on the stage 3 while being guided by the traveling rail 31. The controller 8 controls the operation of the linear motor 50 based on the detection results from the linear encoders 52 and 53, and controls the movement of the bridging structure 4 on the stage 3, that is, the scanning of the substrate 90 by the slit nozzle 41.

  FIG. 3 is a diagram showing the slit nozzle 41 and the resist supply mechanism 6. In FIG. 3, the slit nozzle 41 is shown as a schematic cross section.

  The slit nozzle 41 includes a first main body portion 41a and a second main body portion 41b. Although not shown in detail, a concave portion having a predetermined shape is provided on the joint surface of the first main body portion 41a. The joining surface of the first body part 41a and the joining surface of the second body part 41b are joined so as to face each other in the X-axis direction.

  As described above, the bonding surface between the first main body portion 41a and the second main body portion 41b is bonded, so that the concave portion formed on the bonding surface of the first main body portion 41a becomes the resist solution inside the slit nozzle 41. It becomes the flow path 410. In addition, the recessed part for forming the flow path 410 may be formed in the 2nd main-body part 41b, and may be formed in both.

  Further, the flow path 410 is open in the (−Z) direction, and this opening forms the discharge port 411. The discharge port 411 extends along the longitudinal direction (Y-axis direction) of the slit nozzle 41 and has a slit shape.

  A pipe 42 is connected to the upper center of the slit nozzle 41 so as to directly communicate with the flow path 410. The pipe 42 is an air vent pipe for extracting air accumulated in the slit nozzle 41. As shown in FIG. 3, the pipe 42 is provided independently of the pipe 63 and communicates directly with the flow path 410 in the slit nozzle 41. When the air is extracted from the slit nozzle 41, the piping 42 also extracts the air together with the resist solution, so that the piping 42 also serves as a flow path for the resist solution. That is, the piping 42 has a function as the second flow path in the present invention.

  A pressure sensor 43 is attached to the pipe 42. The pressure sensor 43 installed in the pipe 42 measures the pressure of the resist solution in the pipe 42 and transmits it to the control unit 8. Note that the pressure sensor 43 may measure the pressure of air in the pipe 42. That is, the pressure sensor 43 mainly corresponds to the pressure measuring means in the present invention.

  Further, a valve 44 that opens and closes the pipe 42 according to a control signal from the control unit 8 is attached to the pipe 42. When the resist solution is discharged from the slit nozzle 41 in a coating process or the like, the valve 44 is closed.

  FIG. 4 is a diagram showing measured values of the pressure sensor 43 when the structure of the supply flow path for supplying the resist solution to the slit nozzle 41 is variously changed. The first to sixth structures shown in FIG. 4 are structures corresponding to the first to sixth structures shown in FIG. 11, respectively.

  As shown in FIG. 4, the measured value of the pressure sensor 43 has a small difference in each structure, and it is understood that the influence is small even if the structure of the supply flow path is changed. This shows that the pressure sensor 43 can measure the actual pressure applied to the slit nozzle 41 (flow path 410).

  Returning to FIG. 3, the resist supply mechanism 6 includes a resist bottle 60 for storing a resist solution, a pump 61 for feeding the resist solution, pipes 62 and 63 and valves 64 and 65 serving as a resist solution flow path.

  The pump 61 is driven according to a control signal from the control unit 8 and sucks the resist solution stored in the resist bottle 60 through the pipe 62 and pipes the sucked resist solution toward the slit nozzle 41. The liquid is fed through 63.

  The pipe 62 forms a resist solution flow path from the resist bottle 60 to the pump 61 and is opened and closed by a valve 64 as necessary.

  The pipe 63 is connected to the flow path 410 of the slit nozzle 41 and is opened and closed by a valve 65 as necessary. Although details are omitted in FIG. 3, in the substrate processing apparatus 1 according to the present embodiment, pipes 63 are connected to both ends of the flow path 410 in the Y-axis direction. A flow path for the resist solution between 61 and the slit nozzle 41 is formed.

  That is, the pump 61 has a function of sending the resist liquid to the flow path 410 in the slit nozzle 41 via the first flow path (pipe 63) of the resist liquid. Is supplied from both ends in the Y-axis direction. In addition, the connection structure of the pipe 63 and the flow path 410 is not limited to the connection at both ends in the Y-axis direction, and may be a structure connected to the center, for example.

  A valve 64 attached to the pipe 62 has a function of opening and closing the pipe 62. Similarly, the valve 65 attached to the pipe 63 has a function of opening and closing the pipe 63. Although not shown, the valves 64 and 65 are opened and closed by a control signal from the control unit 8.

  The pressure sensors 66 and 67 are installed in the pipes 62 and 63, respectively. Then, the pressure sensors 66 and 67 measure the pressure of the resist solution fed by the pump 61 and transmit it to the control unit 8.

  With the above configuration, the resist supply mechanism 6 opens and closes the valves 64 and 65 in response to a control signal from the control unit 8 and drives the pump 61. Thereby, the resist solution sucked from the resist bottle 60 is supplied to the flow path 410 of the slit nozzle 41 through the pipes 62 and 63. The resist solution supplied to the slit nozzle 41 (channel 410) is discharged from the slit-shaped discharge port 411 through the channel 410.

  1 and 2, an opening 32 is provided on the holding surface 30 of the main body 2 on the (−X) direction side of the holding area. The opening 32 has a longitudinal direction in the Y-axis direction similar to the slit nozzle 41, and the longitudinal length is substantially the same as the longitudinal direction length of the slit nozzle 41. A nozzle initialization mechanism 7 is provided inside the main body 2 below the opening 32. The nozzle initialization mechanism 7 is used for preliminary processing (described later) that is performed prior to application of the resist solution to the substrate 90.

  FIG. 5 is a diagram showing details of the nozzle initialization mechanism 7 provided in the opening 32. The nozzle initialization mechanism 7 includes a gas supply mechanism 71, an exhaust mechanism 72, a preliminary application mechanism 73, a nozzle cleaning mechanism 74, and a cleaning liquid supply mechanism 75. Hereinafter, the position indicated by the solid line in FIG. 5 of the slit nozzle 41 is referred to as a “preliminary application position”.

  The conventional substrate processing apparatus also includes a mechanism (a mechanism corresponding to the nozzle initialization mechanism 7) for initializing (cleaning or the like) the slit nozzle between application processes on a substrate as a product. Although details will be described later, the substrate processing apparatus 1 according to the present embodiment uses the nozzle initialization mechanism 7 as a mechanism for obtaining parameters in the coating process, thereby reducing the cost and accurately performing the coating process. Control and suppression of arithmetic processing are realized.

  The gas supply mechanism 71 is a mechanism for supplying an inert gas such as nitrogen gas from a cylinder (not shown) to the preliminary application mechanism 73 via the supply pipe 710. The exhaust mechanism 72 is a mechanism that sucks and exhausts the atmosphere in the housing 732 of the preliminary application mechanism 73 via the exhaust pipe 720. As these mechanisms, conventionally known mechanisms can be employed. For example, the exhaust mechanism 72 can be realized by employing a vacuum generator or a compressor.

  The preliminary application mechanism 73 includes a rotation mechanism 730, a roller 731, a housing 732, a liquid draining blade 733, a shielding blade 734, and a shower nozzle 735.

  Although not described in detail, the rotation mechanism 730 is a mechanism including a rotation motor that generates a rotation driving force and a link member that transmits the rotation driving force. The rotational driving force generated by the rotary motor is transmitted to the roller 731 via the link member, and the roller 731 rotates clockwise in FIG.

  The cylindrical roller 731 forms an application surface 731a on which the resist solution is applied from the slit nozzle 41 in the preliminary application process, and the center of the cylinder forms an axis 731b. An axis 731b of the roller 731 is arranged along the Y-axis direction. A rotational driving force is transmitted from the rotation mechanism 730 to the shaft center 731b of the roller 731. As a result, the roller 731 rotates about the shaft center 731b in the clockwise direction in FIG.

  As shown in FIG. 5, the housing 732 is a substantially box-shaped member arranged so that a part of the roller 731 is exposed from the upper surface. An amount of cleaning liquid suitable for immersing a part of the application surface 731 a of the roller 731 is stored in the housing 732. That is, when the rotation mechanism 730 rotates the roller 731, the application surface 731 a of the roller 731 is immersed in the stored cleaning liquid. In addition, the portion of the coating surface 731 a that is immersed in the cleaning liquid is pulled up from the cleaning liquid by the rotation of the roller 731.

  As described above, in the preliminary application mechanism 73, the application liquid 731a of the roller 731 is immersed in the cleaning liquid, whereby the resist liquid applied to the application surface 731a is cleaned and removed. The mechanism for cleaning the application surface 731a is not limited to this, and for example, a nozzle that discharges the cleaning liquid toward the application surface 731a may be provided in the housing 732.

  A liquid draining blade 733 is fixed inside the housing 732. Further, the liquid draining blade 733 includes a plate-like blade 733a that is substantially uniform in the Y-axis direction. The blade 733a is in uniform contact with the Y-axis direction while being slightly pressed toward the application surface 731a of the roller 731. When the roller 731 rotates in this state, the blade 733a and the application surface 731a move relatively, and the application surface 731a is scanned by the blade 733a. In general, it is sufficient for the blade 733a to have a uniform action portion (a portion that comes into contact with the application surface 731a) having an action of removing deposits in the longitudinal direction.

  In this manner, the blade 733a scrapes off deposits (residual resist solution, cleaning solution, etc.) adhering to the coating surface 731a. Since the blade 733a is in uniform contact with the application surface 731a in the Y-axis direction as described above, it is possible to remove deposits from the application surface 731a in a uniform state in the Y-axis direction. The uniformity of the state 731a can be improved. The blade 733a is formed of a material having a hardness lower than that of the application surface 731a, specifically, resin or rubber.

  A gas outlet 732 a is provided on the inner side surface in the longitudinal direction of the housing 732. The gas outlet 732 a has a substantially uniform slit shape along the longitudinal direction of the housing 732, and is an inner opening of a hole that penetrates the side member of the housing 732. In addition, a supply pipe 710 of the gas supply mechanism 71 is connected to the through hole.

  With such a structure, the casing 732 is supplied with an inert gas (for example, clean nitrogen gas) from the gas supply mechanism 71 via the supply pipe 710, and the supplied nitrogen gas is supplied from the gas outlet 732 a to the roller 731. Jetted in a uniform state in the Y-axis direction toward the coating surface 731a. Thus, drying of the cleaning liquid adhering to the application surface 731a is promoted, and the uniformity of the dry state of the application surface 731a in the Y-axis direction can be enhanced.

  The internal atmosphere of the housing 732 is sucked and exhausted by the exhaust mechanism 72 through the exhaust pipe 720 from the suction port 732 b provided on the inner surface in the longitudinal direction of the housing 732. As a result, the solvent atmosphere of the cleaning liquid is quickly exhausted, and the drying of the cleaning liquid adhering to the application surface 731a of the roller 731 is promoted. Note that, in the housing 732, the solvent atmosphere concentration of the cleaning liquid is higher in the vicinity of the bottom of the housing 732. Therefore, in the substrate processing apparatus 1 in the present embodiment, as shown in FIG. 5, the suction port 732b is provided at a low position, whereby the solvent component inside the housing 732 can be efficiently exhausted. .

  In addition, when the roller 731 rotates around the axis 731b, an airflow that flows toward the slit nozzle 41 is generated inside the housing 732 so as to follow the rotation direction of the application surface 731a. Here, contaminants that cause particles such as the solvent component of the cleaning liquid and the removed resist liquid are floating in the internal atmosphere of the housing 732, and it is not preferable that this flows toward the slit nozzle 41. However, the substrate processing apparatus 1 in the present embodiment forms an airflow that flows in the direction indicated by the arrow in FIG. 5 inside the housing 732 by providing the suction port 732b at a position lower than the gas jet port 732a. . Therefore, it is possible to prevent the atmosphere containing the particle causative substance from flowing toward the slit nozzle 41.

  The shielding blade 734 provided on the upper portion of the housing 732 is a plate-like member that is disposed so as to be close to the application surface 731a of the roller 731 (approx. 1 mm) and to be substantially horizontal. With this arrangement, the shielding blade 734 has an atmosphere (atmosphere present on the left side inside the housing 732 in FIG. 5) in which an undried portion of the coating surface 731a is exposed, and the vicinity of the tip of the slit nozzle 41. Shield the atmosphere. Thereby, it can prevent more effectively that the atmosphere containing the component of a washing | cleaning liquid has a bad influence on the front-end | tip part of the slit nozzle 41. FIG.

  The shower nozzle 735 is provided substantially uniformly along the Y-axis direction, and is a nozzle that discharges the cleaning liquid supplied from the cleaning liquid supply mechanism 75 toward the blade 733 a of the liquid draining blade 733. Thereby, the deposits scraped off by the liquid draining blade 733 can be washed away from the blade 733a, and the deposits can be prevented from accumulating on the blade 733a. Therefore, the adhering matter adhering to the application surface 731a by the blade 733a is efficiently removed. Note that the cleaning liquid discharged from the shower nozzle 735 is stored inside the housing 732 and discharged by a drain mechanism (not shown).

  As shown in FIG. 5, in the preliminary application mechanism 73 of the substrate processing apparatus 1 in the present embodiment, the slit nozzle 41, along the rotation direction (clockwise direction in FIG. 5) of the application surface 731a of the roller 731. A cleaning liquid reservoir and a gas outlet 732a are arranged.

  The nozzle cleaning mechanism 74 includes a drive mechanism 740, a guide block 741, and a standby pot 742, and has a function of cleaning and removing the resist solution adhering to the side surface of the slit nozzle 41 by repeating this coating process. .

  The drive mechanism 740 is a mechanism that moves the guide block 741 in the Y-axis direction. As the drive mechanism 740, a general linear motion mechanism using a rotary motor and a ball screw can be employed.

  The guide block 741 is provided so as to be movable along the longitudinal direction (Y-axis direction) of the slit nozzle 41 by the drive mechanism 740. The guide block 741 scans the slit nozzle 41 by moving by the drive mechanism 740 while discharging the cleaning liquid supplied by the cleaning liquid supply mechanism 75 toward the tip of the slit nozzle 41. As a result, the guide block 741 cleans the vicinity of the discharge port 411 of the slit nozzle 41. Prior to the nozzle cleaning process, the slit nozzle 41 has moved to a predetermined position (hereinafter referred to as “cleaning position”). In the nozzle cleaning process, the slit nozzle 41 is moved relative to the slit nozzle 41 at the cleaning position. Scanning by the guide block 741 is performed.

  The standby pot 742 is a substantially box-shaped member that is fixedly disposed almost directly below the guide block 741 and has substantially the same size as the width of the slit nozzle 41 in the longitudinal direction. A resist solution solvent is stored in the standby pot 742. The standby pot 742 is a mechanism provided so that the resist solution in the vicinity of the discharge nozzle 411 of the slit nozzle 41 is not dried and deteriorated when the main coating process is not performed for a relatively long time.

  On the upper surface of the standby pot 742, an opening 742a for inserting the tip of the slit nozzle 41 into the inside is provided. During the standby, the slit nozzle 41 moves to a predetermined position (hereinafter referred to as “standby position”) that is further lowered in the Z-axis direction from the cleaning position. When the slit nozzle 41 is in this standby position, the tip of the slit nozzle 41 is inserted into the standby pot 742 from the opening 742a, and the resist solution is dried by being exposed to the solvent atmosphere. It is suppressed.

  Returning to FIG. 1, the control unit 8 includes a calculation unit 80 that processes various data according to a program and a storage unit 81 that stores the program and various data. Further, on the front surface, an operation unit 82 for an operator to input necessary instructions to the substrate processing apparatus 1 and a display unit 83 for displaying various data are provided.

  The control unit 8 is electrically connected to each mechanism attached to the main body 2 by a cable (not shown) in FIG. Based on the input signal from the operation unit 82 and the signals from the pressure sensors 43, 66, and 67, the control unit 8 moves up and down by the lifting mechanisms 43 and 44, the traveling operation by the traveling mechanism 5, and the registration supply mechanism 6. The resist solution supply operation, and further, the operation of each drive mechanism, each rotation mechanism, each valve, etc. associated with the nozzle initialization mechanism 7 and the preliminary application mechanism 73 are controlled. In particular, the control unit 8 has functions as a movement control unit and a liquid feeding control unit in the present invention, and these functions will be described later.

  Further, a RAM that temporarily stores data, a read-only ROM, a magnetic disk device, and the like correspond to the storage unit 81. Alternatively, it may be a storage medium such as a portable magneto-optical disk or a memory card, and a reading device thereof.

  The operation unit 82 includes buttons and switches (including a keyboard and a mouse). Or what has the function of the display part 83 like a touchscreen display may be used. The display unit 83 corresponds to a liquid crystal display or various lamps.

  The above is description of the structure and function of the substrate processing apparatus 1 in this Embodiment. Next, the operation of the substrate processing apparatus 1 will be described.

  FIG. 6 is a flowchart showing the operation of the substrate processing apparatus 1. When the power is turned on, the substrate processing apparatus 1 performs a predetermined initial setting and then performs a preliminary coating process (step S11).

  7 and 8 are flowcharts showing the details of the control value acquisition process of the substrate processing apparatus 1. In the control value acquisition process, first, the slit nozzle 41 is moved to the cleaning position, scanning by the guide block 741 is performed, and the cleaning process for the slit nozzle 41 is performed (step S21).

  When the cleaning process is completed, the lifting mechanisms 43 and 44 and the traveling mechanism 5 move the slit nozzle 41 to the preliminary application position, and the pressure sensor 66 starts measuring the pressure (step S22).

  When the slit nozzle 41 moves to the preliminary application position, the rotation mechanism 730 of the preliminary application mechanism 73 starts to drive, and the roller 731 starts to rotate. In parallel with this operation, the valves 64 and 65 of the resist supply mechanism are opened, and the pump 61 is driven. When the pump 61 is driven, the resist solution is supplied to the slit nozzle 41, discharged from the discharge port 411, and applied to the application surface 731 a of the roller 731.

  By this series of operations, preliminary application by the preliminary application mechanism 73 is started (step S23), and the pressure therebetween is measured by the pressure sensor 66 and transmitted to the controller 8. That is, the behavior of the pump 61 at the start of driving is observed by the pressure sensor 66.

  When a predetermined time has elapsed since the start of preliminary application in step S23, the resist supply mechanism 6 stops the pump 61 (step S24). Thereby, the preliminary application is temporarily stopped.

  Next, the control unit 8 sets a control value (parameter) of the pump 61 at the start of driving based on the measured value transmitted from the pressure sensor 66 (step S25). Although details are omitted, the control value is set so that overshoot does not occur and the desired discharge flow rate is stabilized in the shortest possible time.

  In the present embodiment, the driving speed value of the pump 61 is used as the control value, but of course it is not limited to this. Moreover, the control part 8 controls the pump 61 in the application | coating process mentioned later based on the set control value.

  By executing the processing of steps S22 to S25 in this way, the control unit 8 applies the resist solution to the substrate 90 based on the measurement result of the pressure sensor 66 when applying the resist solution to the preliminary application mechanism 73. The pump 61 is controlled. That is, as described above, the control unit 8 has a function as a liquid feeding control unit in the present invention.

  FIG. 9 is a diagram illustrating the relationship between the discharge flow rate of the pump 61 and the measured values measured by the pressure sensors 43, 66, and 67, respectively. As is apparent from FIG. 9, since the pressure measurement value varies depending on the position to be measured, it is important which position to measure according to the purpose.

  Here, since the pressure sensor 66 is disposed relatively close to the pump 61 (pipe 62), the behavior of the pump 61 can be accurately observed. Therefore, the substrate processing apparatus 1 can determine the control value for the pump 61 to a more appropriate value. In order to set the control value, the processing of steps S22 to S24 may be repeated a plurality of times while changing the control value.

  When the control value of the pump 61 is set, the pressure measurement by the pressure sensor 43 is started (step S31), the rotation mechanism 730 of the preliminary application mechanism 73 starts to be driven, and the roller 731 starts to rotate. In parallel with this operation, the valves 64 and 65 of the resist supply mechanism are opened, and the pump 61 is driven based on the control value set in step S25. When the pump 61 is driven, the resist solution is supplied to the slit nozzle 41, discharged from the discharge port 411, and applied to the application surface 731 a of the roller 731.

  Preliminary application by the preliminary application mechanism 73 is started by these series of operations (step S32), and the pressure between them is measured by the pressure sensors 43 and 67 and transmitted to the controller 8. In the preliminary application at this time, since the control value of the pump 61 is the control value in the application process, the behavior of the pump 61 reproduces the actual behavior in the application process.

  When a predetermined time has elapsed since the start of the preliminary application in step S32, the resist supply mechanism 6 stops the pump 61 (step S33), and the control unit 8 determines the travel mechanism based on the measured value of the pressure sensor 43 during this time. 5 is set (step S34).

  FIG. 10 is a diagram illustrating the relationship between the measurement value of the pressure sensor 43 and time. In FIG. 10, the measured value of the pressure sensor 67 is indicated by a broken line for reference. In the example shown in FIG. 10, the pump 61 starts driving when 0.5 (sec) has elapsed since the measurement by the pressure sensor 43 was started.

  The measured value of the pressure sensor 67 provided on the primary side of the slit nozzle 41 starts to rise with a delay of 18 (msec) from the start of driving of the pump 61. On the other hand, the measured value of the pressure sensor 43 provided on the secondary side of the slit nozzle 41 starts to rise with a delay of 38 (msec) from the start of driving of the pump 61.

  The discharge of the resist solution from the discharge port 411 of the slit nozzle 41 is started when the pressure in the flow path 410 increases. Therefore, it can be seen from the example of FIG. 10 that even when the pressure increase on the primary side of the slit nozzle 41 is started, the discharge from the slit nozzle 41 is not started at this point. This is because pressure loss occurs in the supply flow path due to a filter (not shown) or a valve 65 provided on the primary side of the slit nozzle 41.

  Therefore, when controlling the scanning of the slit nozzle (controlling the traveling mechanism) based on the measured pressure value on the primary side of the slit nozzle as in the prior art, this delay (20 msec delay in the example shown in FIG. 10) Since control must be performed while compensating for the prediction, there is a problem in that the accuracy decreases.

  However, in the substrate processing apparatus 1, by providing the pressure sensor 43 on the secondary side (pipe 42) of the slit nozzle 41, a value substantially corresponding to the pressure of the flow path 410 can be measured. The state can be grasped accurately. Therefore, the control unit 8 can appropriately set the control value of the traveling mechanism 5 in the coating process. Note that the control unit 8 in the present embodiment sets the control value of the traveling mechanism 5 so that the speed curve of the traveling mechanism 5 follows the rising curve of the measured value by the pressure sensor 43.

  When the control value of the travel mechanism 5 is set, the substrate processing apparatus 1 executes the nozzle initialization process (step S35), ends the control value acquisition process, and returns to the process shown in FIG.

  Although not described in detail, in the nozzle initialization process, first, the slit nozzle 41 is moved to the cleaning position for cleaning, and then the preliminary coating mechanism 73 performs the preliminary coating process. This pre-coating process is a process for forming a resist liquid pool near the discharge port 411 of the slit nozzle 41. Thereafter, the slit nozzle 41 is moved to the standby position, and the nozzle initialization process ends.

  Returning to FIG. 6, when the control value acquisition process is completed, the substrate processing apparatus 1 stands by until the substrate 90 is carried in (step S12), and executes the coating process when the substrate 90 is carried in (step S13).

  When the coating process is started, the traveling mechanism 5 first moves the bridging structure 4 to a position on the substrate 90 where the coating process is performed, and the elevating mechanisms 43 and 44 set the height of the slit nozzle 41 to a predetermined height. Adjust.

  As soon as these position adjustments are completed, the resist supply mechanism 6 starts supplying the resist solution to the slit nozzle 41. At this time, the pump 61 is controlled by the control unit 8 based on the control value set in step S25.

  Further, when the traveling mechanism 5 moves the cross-linking structure 4, a resist solution is applied to the substrate 90, that is, an application process is performed. At this time, the traveling mechanism 5 is controlled by the control unit 8 based on the control value set in step S34.

  When the coating process for one substrate 90 is completed, the nozzle initialization process is executed again (step S14), and it is determined whether or not the process has been completed for all the substrates 90 (step S15). If there are more substrates 90 to be processed, the process returns to step S12 and the process is repeated. If all the substrates 90 have been processed, the process ends.

  As described above, the substrate processing apparatus 1 is provided independently of the pipe 63 for sending the resist solution to the slit nozzle 41, and the pressure sensor 43 is connected to the pipe 42 directly communicating with the flow path 410 in the slit nozzle 41. And controlling the travel mechanism 5 based on the measurement result of the pressure sensor 43, the discharge state of the resist solution can be accurately measured. Therefore, the traveling mechanism 5 can be accurately controlled.

  Further, based on the measurement result of the pressure sensor 43 when applying the resist solution to the preliminary application mechanism 73, the traveling mechanism 5 when applying the resist solution to the substrate 90 is controlled to measure each time the application process is performed. There is no need, and the amount of calculation processing can be suppressed.

  Further, a pressure sensor 66 for measuring the pressure of the resist solution fed by the pump 61 is provided, and the resist solution is applied to the substrate 90 based on the measurement result of the pressure sensor 66 when the resist solution is applied to the preliminary coating mechanism 73. By controlling the pump 61 at the time of application, the pump 61 can be accurately controlled. Therefore, the accuracy in the coating process is further improved.

  Further, by using a pipe 42 for extracting air from the inside of the slit nozzle 41 as a secondary side flow path for providing the pressure sensor 43, it is not necessary to separately provide a flow path for attaching the pressure sensor 43.

  Although not described in detail in the above embodiment, the pressure sensors 66 and 67 in the coating process are used as monitoring sensors for detecting an abnormality (for example, pulsation or the like) of the pump 61. Thereby, the substrate processing apparatus 1 can detect an abnormality in the coating process without separately providing a detection sensor.

<2. Second Embodiment>
In the first embodiment, not only the control value of the pump 61 but also the control value of the traveling mechanism 5 is set in the control value acquisition step (step S11). That is, the control value of the traveling mechanism 5 is also set in advance prior to the coating process.

  However, in the coating process (step S13), the measurement by the pressure sensor 43 is always performed, and the traveling mechanism 5 may be controlled so as to follow the measured value at the start of coating. That is, the traveling mechanism 5 may be controlled according to the measurement result of the pressure sensor 43 every time the coating process is executed.

  Even with such a configuration, the same effects as those of the first embodiment can be obtained.

<3. Modification>
As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various deformation | transformation is possible.

  For example, in the above-described embodiment, it has been described that the nozzle initialization process is executed every time the process for one substrate 90 is completed, but the timing for executing the nozzle initialization process is not limited to this. For example, it may be performed every time a predetermined number of sheets are completed, or may be performed every time a predetermined time elapses. Or you may carry out according to the instruction | indication from an operator.

  In addition, each step shown in the above embodiment is an example, and is not limited to the contents and order shown here. If the same effect can be obtained, the contents or order may be appropriately changed. Good.

1 is a perspective view schematically showing a substrate processing apparatus according to the present invention. It is a figure which shows the main component concerning the application | coating operation | movement of a resist liquid while showing the side cross section of the main body of a substrate processing apparatus. It is a figure which shows a slit nozzle and a resist supply mechanism. It is a figure which shows the measured value of a pressure sensor when the structure of the supply flow path which supplies a resist liquid to a slit nozzle is changed variously. It is a figure which shows the detail of the nozzle initialization mechanism provided in opening. It is a flowchart which shows operation | movement of a substrate processing apparatus. It is a flowchart which shows the detail of the control value acquisition process of a substrate processing apparatus. It is a flowchart which shows the detail of the control value acquisition process of a substrate processing apparatus. It is a figure which illustrates the relationship between the discharge flow rate of a pump, and the measured value each measured with a pressure sensor. It is a figure which illustrates the relationship between the measured value of a pressure sensor, and time. It is a figure which shows the measured value of the pressure sensor provided in the primary side of the slit nozzle at the time of changing the structure of a supply flow path variously.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 41 Slit nozzle 410 Flow path 411 Discharge port 42, 62, 63 Piping 43, 66, 67 Pressure sensor 5 Travel mechanism 50, 51 Linear motor 6 Resist supply mechanism 61 Pump 73 Preliminary application mechanism 8 Control part 90 Substrate

Claims (4)

A substrate processing apparatus for applying a processing liquid to a substrate,
A slit nozzle that is provided with a processing liquid channel inside and discharges the processing liquid from the channel through a slit-like discharge port;
Moving means for relatively moving the substrate on which the processing liquid is applied and the slit nozzle;
A liquid feeding means for feeding the processing liquid to the flow path in the slit nozzle via the first flow path of the processing liquid;
A second flow path for the processing liquid that is provided independently of the first flow path and communicates directly with the flow path in the slit nozzle;
Pressure measuring means installed in the second flow path;
A movement control means for controlling the movement means based on a measurement result of the pressure measurement means;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
A pre-applying portion to which a processing solution is applied prior to processing the substrate;
The movement control means includes
An apparatus for processing a substrate, comprising: controlling the moving means when applying a treatment liquid to a substrate based on a measurement result of the pressure measurement means when applying the treatment liquid to the preliminary application portion. The substrate processing apparatus according to claim 2,
A liquid-feeding pressure measuring means for measuring the pressure of the processing liquid fed by the liquid-feeding means;
Based on the measurement result of the liquid supply pressure measuring means when applying the treatment liquid to the preliminary application unit, the liquid supply control means for controlling the liquid supply means when applying the treatment liquid to the substrate;
A substrate processing apparatus further comprising: A substrate processing apparatus according to any one of claims 1 to 3,
The substrate processing apparatus, wherein the second flow path is a pipe for extracting air from the inside of the slit nozzle.

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