WO2010073801A1

WO2010073801A1 - Illumination optical system, exposure apparatus, and device manufacturing method

Info

Publication number: WO2010073801A1
Application number: PCT/JP2009/067925
Authority: WO
Inventors: 田中　裕久
Original assignee: 株式会社ニコン
Priority date: 2008-12-25
Filing date: 2009-10-16
Publication date: 2010-07-01

Abstract

An illumination optical system, an exposure apparatus, and a device manufacturing method which can adjust the light intensity distribution on the plane to be illuminated. The illumination optical system includes: an optical integrator (26) which has a plurality of cylindrical lens surfaces (54) arranged in an incident plane intersecting the optical axis of the illumination optical system and a plurality of cylindrical lens surfaces (55) arranged in an emission plane intersecting the optical axis further to the emission side than the cylindrical lens surfaces (54), and which forms a predetermined light intensity distribution on an illumination pupil plane (27) in the illumination optical path of the illumination optical system when the exposure light (EL) is incident; and a light shielding unit (66) which is arranged at the incident side of each of the cylindrical lens surfaces (54) and shields a part of the exposure light (EL) incident on some of the cylindrical lens surfaces (54). The light shielding unit (66) has light shielding members (68, 69) having a length in the Y-axis direction greater than the width in the Z-axis direction intersecting the Y-axis direction in the plane intersecting the optical axis.

Description

Illumination optical system, exposure apparatus, and device manufacturing method

The present invention relates to an illumination optical system that illuminates a surface to be irradiated based on light emitted from a light source, an exposure apparatus including the illumination optical system, and a device manufacturing method using the exposure apparatus.

Generally, an exposure apparatus for manufacturing a micro device such as a semiconductor integrated circuit includes an illumination optical system for guiding exposure light output from a light source to a mask such as a reticle on which a predetermined pattern is formed. Such an illumination optical system is provided with a fly-eye lens as an optical integrator. When exposure light is incident on the fly-eye lens, the illumination pupil at a position optically Fourier-transformed with respect to the irradiated surface of the mask on the exit surface side of the fly-eye lens is composed of a number of light sources. A secondary light source is formed as a substantial surface light source. The secondary light source indicates a light intensity distribution at the illumination pupil (hereinafter referred to as “pupil intensity distribution”).

The exposure light from such a secondary light source is condensed by a condenser lens and then illuminates the mask in a superimposed manner. The exposure light transmitted through the mask is irradiated onto a substrate such as a wafer to which a photosensitive material is applied via a projection optical system. As a result, the mask pattern is projected and transferred (transferred) onto the substrate.

Incidentally, in recent years, higher integration (miniaturization) of patterns formed on a mask has been advanced. Therefore, in order to accurately transfer the fine pattern of the mask onto the substrate, it is indispensable to form an irradiation region having a uniform illuminance distribution on the substrate. Therefore, conventionally, in order to accurately transfer the fine pattern of the mask onto the substrate, for example, an annular or multipolar (bipolar, quadrupolar, etc.) pupil intensity distribution is formed, and the focus of the projection optical system A technique for improving depth and resolving power has been proposed (see Patent Document 1).

US Patent Publication No. 2006/0055834

By the way, when the fine pattern of the mask is accurately transferred onto the substrate, not only the pupil intensity distribution is adjusted to a desired shape, but also the light intensity at each point on the substrate, which is the final irradiated surface, is approximately It is necessary to adjust uniformly. If there is variation in the light intensity at each point on the substrate, the line width of the pattern varies from position to position on the substrate, and the fine pattern of the mask is accurately applied to the substrate with the desired line width over the entire exposure area. There was a possibility that it could not be transferred.

The present invention has been made in view of such circumstances, and an object thereof is to provide an illumination optical system, an exposure apparatus, and a device manufacturing method capable of adjusting a light intensity distribution on an irradiated surface. There is.

In order to solve the above-described problems, the present invention employs the following configuration corresponding to FIGS. 1 to 17 shown in the embodiment.
The illumination optical system of the present invention is an illumination optical system (13) that illuminates the irradiated surface (Ra, Wa) with light (EL) from a light source (12), and the optical axis of the illumination optical system (13). A plurality of incident side optical surfaces (52, 54) arranged in planes (50a, 50b) intersecting with (AX), and the irradiated surface (Ra) from the plurality of incident side optical surfaces (52, 54). , Wa) side, a plurality of exit side optical surfaces (53, 53) arranged in planes (51a, 51b) intersecting the optical axis (AX) and individually corresponding to the plurality of entrance side optical surfaces (52, 54). 55), and forms a predetermined light intensity distribution on the illumination pupil plane (27) in the illumination optical path of the illumination optical system (13) when light (EL) from the light source (12) enters. The integrator (26) and the plurality of incident-side optical surfaces (52, 54); A dimming unit (66) disposed on the source (12) side for dimming a part of light (EL) incident on at least some of the incident side optical surfaces (52, 54). , 66A), and the dimming portion (66, 66A) has a width along a first direction intersecting the optical axis direction of the illumination optical system in a plane intersecting the optical axis (AX). The gist is that the length along the optical axis direction is longer than that.

According to the above configuration, part of the light that is about to enter at least some of the incident-side optical surfaces (52, 54) of the optical integrator (26) is a light source of the optical integrator (26). It is dimmed by the dimming part (66, 66A) arranged on the (12) side. The light intensity distribution (also referred to as “pupil intensity distribution”) at each point on the irradiated surface (Ra, Wa) is independently adjusted by the light reducing action by the light reducing section (66, 66A). Therefore, it is possible to adjust the light intensity distribution at each point on the irradiated surface (Ra, Wa) to a distribution having substantially the same property.

In addition, in order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings showing the embodiments, but it goes without saying that the present invention is not limited to the embodiments.

According to the present invention, the light intensity distribution on the irradiated surface can be adjusted.

1 is a schematic block diagram that shows an exposure apparatus according to a first embodiment. The perspective view which shows a pair of micro fly's eye lens typically. The schematic diagram which shows the quadrupole secondary light source formed in an illumination pupil plane. (A) is a schematic diagram which shows the illumination area | region formed on a reticle, (b) is a schematic diagram which shows the static exposure area | region formed on a wafer. The schematic diagram which shows the 1st pupil intensity distribution formed with the incident light which injects into the center point in a still exposure area | region. The schematic diagram which shows the 2nd pupil intensity distribution formed with the incident light which injects into the peripheral point in a still exposure area | region. (A) is a graph showing the light intensity along the Z-axis direction of the first pupil intensity distribution corresponding to the center point in the still exposure area, and (b) is the second pupil intensity corresponding to the peripheral points in the still exposure area. The graph which shows the light intensity along the Z-axis direction of distribution. The front view which shows typically the distribution correction unit in 1st Embodiment. The action figure which shows typically the light-shielding aspect of the exposure light by each light-shielding member arrange | positioned in a boundary position. FIG. 5 is an operation diagram schematically showing a relationship between an incident angle of exposure light with respect to a first micro fly's eye lens and a length along a Y-axis direction of a light shielding member. (A) is a schematic diagram which shows 1st pupil intensity distribution in case each light shielding member is arrange | positioned in a boundary position, (b) is a schematic diagram which shows 2nd pupil intensity distribution. The action figure which shows typically the light-shielding aspect of the exposure light by each light-shielding member arrange | positioned in a center position. (A) is a schematic diagram which shows the 1st pupil intensity distribution in case each light shielding member is arrange | positioned in a center position, (b) is a schematic diagram which shows a 2nd pupil intensity distribution. The schematic block diagram which shows the distribution correction unit in 2nd Embodiment. The front view which shows typically a part of distribution correction unit in another embodiment. The flowchart of the manufacture example of a device. The detailed flowchart regarding the board | substrate process in the case of a semiconductor device.

DESCRIPTION OF SYMBOLS 11 ... Exposure apparatus, 12 ... Light source device, 13 ... Illumination optical system, 15 ... Projection optical system, 26 ... Optical integrator, 27 ... Illumination pupil plane, 36 ... Pupil intensity distribution measuring device, 40 ... Control apparatus, 42 ... Aperture stop , 50... First micro fly's eye lens as the first optical member, 51. Second micro fly's eye lens as the second optical member, 50 a, 51 a... Entrance surface, 50 b and 51 b. Cylindrical lens surface as a side optical surface, 53... Cylindrical lens surface as a first emission side optical surface, 54... Cylindrical lens surface as a second incidence side optical surface, 55 ... Cylindrical lens surface as a second emission side optical surface , 66, 66A: a light shielding part as a light reducing part, 68 to 71, 87: a light shielding member as a light reducing member, 72: a moving mechanism, 77: partial incidence Effective lens surface as optical surface, AX ... optical axis, EL ... exposure light, P1a to P3a, P1b to P3b ... point as predetermined point, Ra ... irradiated surface, W ... wafer as substrate, Wa ... irradiated Surface as a face.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the optical axis (vertical direction in FIG. 1) of the projection optical system 15 to be described later is referred to as the Z-axis direction, the horizontal direction in FIG. 1 is referred to as the Y-axis direction, and in FIG. The direction to do is referred to as the X-axis direction.

As shown in FIG. 1, the exposure apparatus 11 of the present embodiment illuminates exposure light EL onto a transmissive reticle R on which a predetermined circuit pattern is formed, thereby providing a surface Wa (+ Z direction side surface). 1 is an apparatus for projecting an image of a circuit pattern onto a wafer W coated with a photosensitive material such as a resist on the upper surface in FIG. Such an exposure apparatus 11 includes an illumination optical system 13 that guides the exposure light EL emitted from the light source device 12 to an irradiated surface Ra (surface on the + Z direction side) of the reticle R, a reticle stage 14 that holds the reticle R, and a reticle. A projection optical system 15 that guides the exposure light EL that has passed through R to the surface Wa of the wafer W, and a wafer stage 16 that holds the wafer W are provided. Note that the light source device 12 of this embodiment has an ArF excimer laser light source that outputs light having a wavelength of 193 nm, and light output from the ArF excimer laser light source is guided into the exposure device 11 as exposure light EL.

The illumination optical system 13 includes a shaping optical system 17 for converting the exposure light EL emitted from the light source device 12 into a parallel light beam having a predetermined cross-sectional shape (for example, a substantially rectangular cross section), and the shaping optical system 17. And a first reflection mirror 18 that reflects the exposure light EL emitted from the light to the reticle R side (here, the + Y direction side and the right side in FIG. 1). A diffractive optical element 19 is provided on the exit side (reticle R side) of the first reflecting mirror 18. The diffractive optical element 19 is formed by forming a plurality of steps having a pitch approximately equal to the wavelength of the exposure light EL on the glass substrate. The diffractive optical element 19 receives the exposure light EL incident from the incident side (light source device 12 side). It has the effect of diffracting to a predetermined angle. For example, when the diffractive optical element 19 for annular illumination is used, when the exposure light EL of a parallel light beam having a substantially rectangular cross section is incident on the diffractive optical element 19 from the incident side, the cross-sectional shape is changed from the diffractive optical element 19. A luminous flux having an annular shape (substantially annular shape) is emitted to the reticle R side. Further, when the diffractive optical element 19 for illuminating a plurality of poles (two poles, four poles, eight poles, etc.) is used, exposure light EL of a parallel light beam having a substantially rectangular cross section enters the diffractive optical element 19 from the incident side. From the diffractive optical element 19, a plurality of (for example, four) light beams corresponding to the number of poles are emitted to the reticle R side.

In addition, the illumination optical system 13 is provided with an afocal optical system 20 (also referred to as “non-focal optical system”) on which the exposure light EL emitted from the diffractive optical element 19 is incident. The afocal optical system 20 includes a first lens group 21 (only one lens is shown in FIG. 1) and a second lens group 22 (shown in FIG. 1) arranged on the exit side from the first lens group 21. Only one lens is shown). The focal position on the incident side of the afocal optical system 20 is substantially the same as the installation position of the diffractive optical element 19, and the focal position on the exit side of the afocal optical system 20 is a predetermined surface indicated by a broken line in FIG. It is formed so as to be substantially the same as the position 23.

Further, in the optical path between the first lens group 21 and the second lens group 22, the incident position of the exposure light EL is at a position optically conjugate with or near the illumination pupil plane 27 of the optical integrator 26 described later. A correction filter 24 having a transmittance distribution with different transmittances is provided. The correction filter 24 is a filter in which a light-shielding dot pattern made of chromium, chromium oxide, or the like is formed on a glass substrate whose incident side surface and emission side surface are parallel.

Further, on the reticle R side of the afocal optical system 20, a zoom for varying the σ value (σ value = the numerical aperture on the reticle R side of the illumination optical system 13 / the numerical aperture on the reticle R side of the projection optical system 15). An optical system 25 is provided, and the zoom optical system 25 is disposed on the exit side with respect to the predetermined surface 23. Further, on the exit side of the zoom optical system 25, an optical integrator 26 and a distribution correction unit 31 for adjusting the amount of exposure light EL incident on the optical integrator 26 are provided. The distribution correction unit 31 includes an illumination region ER1 (see FIG. 4A) formed on the reticle R and a static exposure region ER2 formed on the wafer W that is optically conjugate with the illumination region ER1. This is a unit for correcting the light intensity distribution at each point in (see FIG. 4B). The specific configuration of the distribution correction unit 31 will be described later.

The optical integrator 26 has an incident surface (a surface on the −Y direction side, which is the left surface in FIG. 1) located at a focal position (also referred to as a pupil plane) on the exit side of the zoom optical system 25 or in the vicinity of the focal position. Are arranged as follows. That is, the incident surface of the optical integrator 26 has a substantially Fourier transform relationship with the predetermined surface 23, and the incident surface of the optical integrator 26 is the pupil plane of the afocal optical system 20 (that is, the installation position of the correction filter 24). ) And an optically conjugate positional relationship. The exposure light EL is incident on such an optical integrator 26 in a state of being converted into a parallel light beam from the zoom optical system 25 side. Then, the optical integrator 26 wave-divides the incident exposure light EL into a plurality of light beams, and a predetermined light intensity distribution (also referred to as “pupil intensity distribution”) on the illumination pupil plane 27 located on the exit side (+ Y direction side). .). The illumination pupil plane 27 on which the pupil intensity distribution is formed is also referred to as a secondary light source 60 (see FIG. 3) composed of a number of surface light sources.

On the exit side of the optical integrator 26, an illumination aperture stop (not shown) is provided at a position optically conjugate with the entrance pupil plane of the projection optical system 15 and defines a range contributing to illumination of the secondary light source 60. Is provided. This illumination aperture stop has a plurality of openings having different sizes and shapes. In the illumination aperture stop, an opening corresponding to the cross-sectional shape of the exposure light EL emitted from the secondary light source 60 is disposed in the optical path of the exposure light EL. That is, when the cross-sectional shape of the exposure light EL emitted from the secondary light source 60 is an annular shape, the illumination aperture stop is driven so that the opening corresponding to the annular shape is located in the optical path of the exposure light EL. It is supposed to be. In addition, when the cross-sectional shape of the exposure light EL emitted from the secondary light source 60 is quadrupole, the illumination aperture stop has an opening having a shape corresponding to the quadrupole shape in the optical path of the exposure light EL. To drive.

On the exit side of the optical integrator 26 and the illumination aperture stop, there is a first condenser optical system 28 composed of at least one lens (only one is shown in FIG. 1), and the exit side of the first condenser optical system 28. In addition, a reticle blind 29 (also referred to as a “mask blind”) disposed at a position optically conjugate with the irradiated surface Ra of the reticle R is provided. The first condenser optical system 28 includes an optical element (lens) having power (reciprocal of focal length). The reticle blind 29 is formed with a rectangular opening 29a whose longitudinal direction is the Z-axis direction and whose lateral direction is the X-axis direction. The exposure light EL emitted from the first condenser optical system 28 illuminates the reticle blind 29 in a superimposed manner. The optical element having power is an optical element in which the characteristics of the exposure light EL change when the exposure light EL enters the optical element.

Further, a second condenser optical system 30 composed of a lens having power is provided on the exit side of the reticle blind 29, and the second condenser optical system 30 substantially receives light incident from the reticle blind 29 side. The light is converted into a parallel light beam. An imaging optical system 32 is provided on the exit side of the second condenser optical system 30. The imaging optical system 32 includes an incident side lens group 33, a second reflecting mirror 34 that reflects the exposure light EL emitted from the incident side lens group 33 to the −Z direction side (lower side in FIG. 1), And an exit side lens group 35 disposed on the exit side of the second reflecting mirror 34. The incident side lens group 33 is composed of at least one optical element (lens) having power (only one is shown in FIG. 1), and the emission side lens group 35 is at least one (one in FIG. 1). It is comprised from the optical element (lens) which has the power of only illustration. The exposure light EL emitted from the imaging optical system 32 illuminates the irradiated surface Ra of the reticle R in a superimposed manner. In the present embodiment, the shape of the opening 29a of the reticle blind 29 is rectangular as described above. Therefore, as shown in FIGS. 4A and 4B, the illumination area ER1 on the reticle R and the static exposure area ER2 on the wafer W are in the Y-axis direction as the first direction and short. Each is formed in a rectangular shape whose direction is the X-axis direction as the second direction.

As shown in FIG. 1, the reticle stage 14 is arranged on the object plane side of the projection optical system 15 so that the mounting surface of the reticle R is substantially orthogonal to the optical axis direction (Z-axis direction) of the projection optical system 15. Has been. The reticle stage 14 is provided with a reticle stage drive unit (not shown) that moves the held reticle R with a predetermined stroke in the X-axis direction.

Further, a pupil intensity distribution measuring device 36 is provided in the vicinity of the reticle stage 14. The pupil intensity distribution measuring device 36 is a device that measures the pupil intensity distribution formed by each incident light incident on one point in the illumination area ER1 on the reticle R in the secondary light source 60 for each point (for each position). . The pupil intensity distribution measuring device 36 includes a beam splitter 37 that reflects part of the exposure light EL (also referred to as “reflected light”) emitted from the exit side lens group 35 toward the reticle R, and the beam splitter 37. A measurement lens 38 on which the reflected light reflected by the laser beam enters, and a detection unit 39 on which the reflected light emitted from the measurement lens 38 enters. The detection unit 39 includes a CCD imaging device, a photodiode, and the like, and a detection signal corresponding to the incident reflected light is output from the detection unit 39 to the control device 40. And the control apparatus 40 derives | leads-out the pupil intensity distribution for every point of the illumination area ER1 based on the detection signal from the detection part 39. FIG. The pupil intensity distribution measuring device 36 is disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-54328, Japanese Patent Application Laid-Open No. 2003-22967, and US Patent Publication No. 2003/0038225 corresponding thereto.

The projection optical system 15 includes a lens barrel 41 filled with an inert gas such as nitrogen, and a plurality of lenses (not shown) are provided in the lens barrel 41 along the optical path (Z-axis direction) of the exposure light EL. Is provided. In addition, an aperture stop 42 is disposed in the lens barrel 41 at a position that is optically Fourier-transformed with the installation position of the surface Wa of the wafer W and the installation position of the irradiated surface Ra of the reticle R. Then, the image of the circuit pattern on the reticle R illuminated with the exposure light EL is projected and transferred onto the wafer W on the wafer stage 16 in a state reduced to a predetermined reduction magnification via the projection optical system 15. . Here, the optical path indicates a path through which the exposure light EL is intended to pass in the use state.

The wafer stage 16 includes a planar mounting surface 43 that is substantially orthogonal to the optical axis of the projection optical system 15, and the wafer W is mounted on the mounting surface 43. The wafer stage 16 is provided with a wafer stage driving unit (not shown) that moves the wafer W to be held in the X-axis direction with a predetermined stroke. Further, the wafer stage 16 is provided with a function of finely adjusting the position of the wafer W so that the surface Wa of the wafer W is perpendicular to the optical axis of the projection optical system 15.

When a pattern image is projected onto the wafer W using the exposure apparatus 11 of the present embodiment, the reticle R is driven from the + X direction side to the −X direction side (near the paper surface in FIG. 1) by driving the reticle stage driving unit. From the side to the back side of the drawing) at every predetermined stroke. Then, the illumination area ER1 on the reticle R moves from the −X direction side of the irradiated surface Ra of the reticle R along the + X direction side (in FIG. 1, from the back side to the front side of the paper). That is, the pattern of the reticle R is sequentially scanned from the −X direction side to the + X direction side. The wafer W is driven from the −X direction side to the + X direction side at a speed ratio corresponding to the reduction magnification of the projection optical system 15 with respect to the movement of the reticle R along the X-axis direction by driving the wafer stage driving unit. Move synchronously. As a result, a pattern having a shape obtained by reducing the circuit pattern on the reticle R to a predetermined reduction ratio is formed in one shot region of the wafer W in accordance with the synchronous movement of the reticle R and the wafer W. When the pattern formation on one shot area is completed, the pattern formation on the other shot areas of the wafer W is continuously performed.

Next, the optical integrator 26 of this embodiment will be described with reference to FIG. In FIG. 2, it is assumed that the sizes of the cylindrical lens surfaces 52, 53, 54, and 55, which will be described later, are exaggerated for convenience of understanding the description.

As shown in FIG. 2, the optical integrator 26 includes a pair of micro fly's

eye lenses

50 and 51 arranged along the optical axis AX of the illumination optical system 13 (indicated by a one-dot chain line in FIGS. 1 and 2). ing. These micro fly's

eye lenses

50 and 51 are respectively arranged so that the illumination pupil plane 27 located on the exit side of the optical integrator 26 is formed at a position optically conjugate with the aperture stop 42 of the projection optical system 15. Yes.

On the incident side of the first micro fly's eye lens 50 positioned on the incident side and on the incident side of the second micro fly's eye lens 51 positioned on the exit side, an incident surface 50a that is substantially orthogonal to the optical axis AX of the illumination optical system 13. , 51a are formed. Further, on the exit side of the first micro fly's eye lens 50 and the exit side of the second micro fly's eye lens 51, exit surfaces 50b and 51b that are substantially orthogonal to the optical axis AX of the illumination optical system 13 are formed, respectively. . A plurality of (10 in FIG. 2) cylindrical lens surfaces 52 and 53 extending in the Z-axis direction as the third direction are on the incident surfaces 50a and 51a side of both the micro fly's

eye lenses

50 and 51. They are arranged along the X-axis direction as a direction. Each of the cylindrical lens surfaces 52 and 53 is formed so as to have a shape obtained by cutting a part of a cylinder, and the length (that is, the width) of each

cylindrical lens surface

52 and 53 in the X-axis direction is the first. One width H1.

In addition, a plurality (10 in FIG. 2) of cylindrical lens surfaces 54 and 55 extending in the X-axis direction are arranged along the Z-axis direction on the exit surfaces 50b and 51b side of both the micro fly's

eye lenses

50 and 51, respectively. ing. Each of the cylindrical lens surfaces 54 and 55 is formed to have a shape obtained by cutting a part of a cylinder, and the length (that is, the width) of each

cylindrical lens surface

54 and 55 in the Z-axis direction is the first. The second width H2 is wider than the first width H1. The first width H1 and the second width H2 are the length in the X-axis direction and the length in the Z-axis direction of the opening 29a of the reticle blind 29, that is, the length in the X-axis direction of the illumination area ER1 and the still exposure area ER2. And the length in the Y-axis direction correspond to each other.

When attention is paid to the refraction action in the X-axis direction of the optical integrator 26, the exposure light EL (that is, the parallel light beam) incident along the optical axis AX of the illumination optical system 13 is incident on the incident surface 50a of the first micro fly's eye lens 50. Each of the cylindrical lens surfaces 52 is divided into wavefronts at intervals of the first width H1 along the X-axis direction. The light beams divided by the respective cylindrical lens surfaces 52 are focused on the corresponding cylindrical lens surfaces among the respective cylindrical lens surfaces 53 formed on the incident surface 51a of the second micro fly's eye lens 51. After that, the light is condensed on the illumination pupil plane 27 located on the exit side of the optical integrator 26. Further, when attention is paid to the refractive action of the optical integrator 26 in the Z-axis direction, the exposure light EL (that is, the parallel light beam) incident along the optical axis AX of the illumination optical system 13 is emitted from the first micro fly's eye lens 50. Wavefront division is performed at intervals of the second width H2 along the Z-axis direction by the cylindrical lens surfaces 54 formed on the surface 50b. The light beams divided by the respective cylindrical lens surfaces 54 are condensed on the corresponding cylindrical lens surfaces among the respective cylindrical lens surfaces 55 formed on the exit surface 51b of the second micro fly's eye lens 51. After that, the light is condensed on the illumination pupil plane 27 located on the exit side of the optical integrator 26. As a result, a large number of point light sources 78 (see FIG. 9) are formed on the illumination pupil plane 27.

In addition, the first width H1 and the second width H2 of the cylindrical lens surfaces 52 to 55 of the micro fly's

eye lenses

50 and 51 are originally very narrow. Therefore, the number of wavefront divisions in the optical integrator 26 of the present embodiment is larger than when a fly-eye lens composed of a plurality of lens elements is used. As a result, the global light intensity distribution formed on the incident side of the optical integrator 26 and the global light intensity distribution of the entire secondary light source formed on the illumination pupil plane 27 on the exit side are highly correlated with each other. Show the relationship. Therefore, the light intensity distribution on the incident side of the optical integrator 26 and on a surface optically conjugate with the incident side can also be referred to as a pupil intensity distribution.

Here, when a diffractive optical element for annular illumination is used as the diffractive optical element 19, an annular illumination field around the optical axis AX of the illumination optical system 13 is formed on the incident side of the optical integrator 26. The As a result, an annular secondary light source 60 is formed on the illumination pupil plane 27 located on the exit side of the optical integrator 26, the same as the annular illumination field formed on the incident side. When a diffractive optical element for multipole illumination is used as the diffractive optical element 19, a plurality of predetermined shapes (arc shape, circular shape) around the optical axis AX of the illumination optical system 13 are provided on the incident side of the optical integrator 26. A multipolar illuminating field is formed. As a result, a multipolar secondary light source 60 is formed on the illumination pupil plane 27 located on the exit side of the optical integrator 26, the same as the multipolar illumination field formed on the incident side. In the present embodiment, a diffractive optical element 19 for quadrupole illumination is used.

That is, on the illumination pupil plane 27 located on the exit side of the optical integrator 26, as shown in FIG. 3, four arc-shaped substantial surface light sources (hereinafter simply referred to as “surface light sources”) 60a, 60b, A quadrupolar secondary light source 60 (pupil intensity distribution) composed of 60c and 60d is formed. Specifically, the secondary light source 60 includes an arcuate first surface light source 60a positioned on the + X direction side of the optical axis AX of the illumination optical system 13, and a −X direction side of the optical axis AX of the illumination optical system 13. A second arc surface-shaped second surface light source 60b is provided, and the distance between the first surface light source 60a and the optical axis AX is substantially equal to the distance between the second surface light source 60b and the optical axis AX. Yes. The secondary light source 60 includes an arcuate third surface light source 60c positioned on the + Z direction side of the optical axis AX of the illumination optical system 13, and a circle positioned on the −Z direction side of the optical axis AX of the illumination optical system 13. An arcuate fourth surface light source 60d is provided, and the distance between the third surface light source 60c and the optical axis AX is substantially equal to the distance between the fourth surface light source 60d and the optical axis AX. Each of the surface light sources 60a to 60d is composed of a number of point light sources 78 (see FIG. 9) formed on the illumination pupil plane 27 by the optical integrator 26.

When each exposure light EL emitted from each of the surface light sources 60a to 60d is guided onto the reticle R, as shown in FIG. 4A, the longitudinal direction is on the Y-axis on the irradiated surface Ra of the reticle R. A rectangular illumination region ER1 that is a direction and whose short direction is the X-axis direction is formed. Further, as shown in FIG. 4B, a rectangular still exposure region ER2 corresponding to the illumination region ER1 on the reticle R is formed on the surface Wa of the wafer W. At this time, each of the quadrupole pupil intensity distributions formed by the incident light incident on each point in the still exposure region ER2 (and the illumination region ER1) does not depend on the position where the exposure light EL is incident on each other. It has almost the same shape. However, the light intensity of the quadrupole pupil intensity distribution for each point in the still exposure region ER2 (and the illumination region ER1) tends to vary depending on the position of the exposure light EL incident on the still exposure region ER2. There is.

Specifically, as shown in FIG. 5, exposure light EL (also referred to as “first incident light”) incident on center points P1a and P1b in the Y-axis direction in the illumination region ER1 and the static exposure region ER2. In the formed first pupil intensity distribution 61, the light intensity of the third surface light source 61c and the fourth surface light source 61d arranged along the Z-axis direction is the first surface arranged along the X-axis direction. There is a tendency to be stronger than the light intensity of the light source 61a and the second surface light source 61b. On the other hand, as shown in FIGS. 4A and 4B and FIG. 6, the peripheral points P2a, P3a, P2b, which are separated from the center points P1a, P1b in the Y-axis direction in the illumination region ER1 and the still exposure region ER2. Each exposure light EL incident on P3b (hereinafter, light incident on the peripheral point P2b is also referred to as “second incident light” and light incident on the peripheral point P3b is also referred to as “third incident light”). In the second pupil intensity distribution 62, the light intensity of the third surface light source 62c and the fourth surface light source 62d arranged along the Z-axis direction is the first surface light source 62a arranged along the X-axis direction and It tends to be weaker than the light intensity of the second surface light source 62b. The

pupil intensity distributions

61 and 62 referred to here are obtained when the correction filter 24 and

light shielding members

68, 69, 70, and 71 to be described later are not arranged in the optical path of the exposure light EL in the illumination optical system 13. It shows the light intensity distribution corresponding to each point P1b, P2b, P3b in the still exposure region ER2 formed on the illumination pupil plane 27 and a pupil conjugate plane optically conjugate with the illumination pupil plane 27.

In general, the light intensity distribution along the Z-axis direction of the first pupil intensity distribution 61 corresponding to the center points P1a and P1b has the weakest center in the Z-axis direction as shown in FIG. The distribution is a concave curve that gradually becomes stronger as the distance from the first Z-axis increases along the Z-axis direction. Further, the light intensity distribution along the Z-axis direction of each second pupil intensity distribution 62 corresponding to each peripheral point P2a, P2b, P3a, P3b has a center in the Z-axis direction as shown in FIG. The distribution is a convex curved surface that becomes the strongest and gradually weakens as the distance from the center along the Z-axis direction increases.

The light intensity distribution along the Z-axis direction of the

pupil intensity distributions

61 and 62 hardly depends on the position of each point along the X-axis direction in the illumination region ER1 and the still exposure region ER2, but the illumination region ER1 and There is a tendency to change depending on the position of each point along the Y-axis direction in the still exposure region ER2. Therefore, when the

pupil intensity distributions

61 and 62 individually corresponding to the points P1b, P2b, and P3b along the Y-axis direction in the still exposure region ER2 are not uniform, the line width of the pattern formed on the wafer W is set. Variations may occur. In order to solve such a problem, a correction filter 24 and a distribution correction unit 31 are provided in the illumination optical system 13 of the present embodiment.

In addition, the correction filter 24 of this embodiment dimmes the light flux that constitutes the third surface light source 60c and the fourth surface light source 60d along the Z-axis direction among the secondary light sources 60 formed on the illumination pupil plane 27. On the other hand, it has a transmittance distribution that hardly diminishes the light beams constituting the first surface light source 60a and the second surface light source 60b along the X-axis direction.

Next, the distribution correction unit 31 of this embodiment will be described with reference to FIGS.
As shown in FIG. 8, the distribution correction unit 31 includes a support member 65 having a square ring shape, and one of the cylindrical lens surfaces 54 supported by the support member 65 and on the exit side of the first micro fly's eye lens 50. And a light shielding part 66 as a light reducing part for shielding part of the exposure light EL that is to be incident on the lens surface of the part. The support member 65 is formed with an opening 65 a having a shape surrounding the optical path of the exposure light EL that can enter the micro fly's

eye lenses

50 and 51.

Surface light sources

67a and 67b individually corresponding to the surface light sources 60a to 60d formed on the illumination pupil plane 27 on the incident surface 50a of the first micro fly's eye lens 50 by the exposure light EL that has passed through the opening 65a. , 67c, 67d are formed.

The light shielding portion 66 includes a plurality of (four in the present embodiment)

light shielding members

68, 69, 70, 71 as light-reducing members that extend along the X-axis direction that is the direction in which the cylindrical lens surfaces 54, 55 extend. A moving mechanism 72 for individually moving the light shielding members 68 to 71 and an advance / retreat mechanism (not shown) for moving the light shielding members 68 to 71 forward and backward between the optical path of the exposure light EL and the outside of the optical path are provided. ing. The moving mechanism 72 is provided with a plurality of

drive sources

73, 74, 75, and 76 that individually correspond to the light shielding members 68 to 71, and each of the drive sources 73 to 76 responds to a control command from the control device 40. Each is driven based on this. Each of the drive sources 73 to 76 has a first driving force for moving the light shielding members 68 to 71 in the Z-axis direction that is the width direction of the cylindrical lens surfaces 54 and 55, and the light shielding members 68 to 71 to the optical axis. The second driving force for moving in the Y-axis direction, which is the direction, can be applied to each light shielding member 68-71.

Each of the light shielding members 68 to 71 includes a plurality (two in the present embodiment) of first

light shielding members

68 and 69 positioned on the + X direction side (right side in FIG. 8) of the optical axis AX of the illumination optical system 13, and illumination. The optical system 13 is classified into a plurality (two in the present embodiment) of second

light shielding members

70 and 71 located on the −X direction side (left side in FIG. 8) of the optical axis AX. The first

light shielding members

68 and 69 are light shielding members respectively disposed in the optical path of the exposure light EL that forms the first surface light source 67a on the incident surface 50a of the first micro fly's eye lens 50. Each of the second

light shielding members

70 and 71 is a light shielding member disposed in the optical path of the exposure light EL that forms the second surface light source 67b on the incident surface 50a of the first micro fly's eye lens 50. When each of the light shielding members 68 to 71 is disposed in the optical path of the exposure light EL, the light shielding member 68 to 71 shields part of the exposure light EL that is about to enter the first micro fly's eye lens 50, thereby exposing the exposure light EL. The light intensity of each of the first surface light source 67a and the second surface light source 67b is weakened as compared with the case where the light source is not arranged in the optical path.

Further, as shown in FIG. 9, each of the light shielding members 68 to 71 extends along a direction (X-axis direction in this embodiment) corresponding to the scanning direction (X-axis direction) of the wafer W and the reticle R at the time of exposure. Each is formed in a quadrangular prism shape. Each of the light shielding members 68 to 71 has a length (hereinafter referred to as “width”) D in the Z-axis direction orthogonal to the Y-axis direction, which is the optical axis direction, of the second width of the cylindrical lens surfaces 54 and 55. Each is formed so as to be narrower than H2. The light shielding members 68 to 71 are formed such that their length in the Y-axis direction (hereinafter simply referred to as “length”) L is longer than their width D. Moreover, the length L and the width D of each of the light shielding members 68 to 71 satisfy the following conditional expression (Expression 1).

Where L is the length of the light shielding members 68 to 71, D is the width of the light shielding members 68 to 71, θ is the incident angle of the exposure light with respect to the exit surface 50b of the first micro fly's eye lens 50. Of these, the exposure light EL is always incident on the effective lens surface 77 regardless of the arrangement positions of the light shielding members 68 to 71. Note that the “effective lens surface 77” indicates a cylindrical lens surface on which the exposure light EL is incident among the cylindrical lens surfaces 54.

Here, in the present embodiment, a parallel light beam is incident on the first micro fly's eye lens 50. However, each incident light (also referred to as a “light beam”) constituting such a parallel light flux has an effective lens surface 77 with various incident angles θ with respect to the exit surface 50 b of the first micro fly's eye lens 50. Trying to enter. Therefore, when the width D and the length L of each of the light shielding members 68 to 71 do not satisfy the conditional expression (Formula 1), the exposure light EL that is about to enter the effective lens surface 77 is reflected on the effective lens surface 77. Since the light shielding members 68 to 71 are almost shielded from light, the exposure light EL may hardly enter. Therefore, each of the light shielding members 68 to 71 may be designed so as to satisfy the conditional expression (Expression 1).

When each of the light shielding members 68 to 71 is disposed at a position corresponding to the boundary portion between the effective lens surfaces 77 adjacent in the Z-axis direction (hereinafter referred to as “boundary position”), as shown in FIG. The light shielding members 68 to 71 allow the exposure light EL to enter the central portion of the effective lens surface 77 in the Z-axis direction, respectively. On the other hand, each of the light shielding members 68 to 71 shields the exposure light EL that is about to enter both ends of the effective lens surface 77 in the Z-axis direction. At this time, most of the exposure light EL that is not shielded by the light shielding members 68 to 71 is light emitted from the illumination pupil plane 27 along the direction in which the optical axis AX of the illumination optical system 13 extends. That is, the exposure light EL is first incident light that forms the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 corresponding to the center point P1b of the still exposure region ER2. Further, most of the exposure light EL shielded by each of the light shielding members 68 to 71 from the illumination pupil plane 27 in a state having a predetermined angle with respect to the optical axis AX of the illumination optical system 13 when not shielded. Light that is emitted. That is, most of the exposure light EL is not shielded from light, the first surface light source 62a and the second surface light source of the second pupil intensity distribution 62 corresponding to the peripheral points P2b and P3b of the still exposure region ER2. Second incident light and third incident light forming 62b.

Therefore, when the respective light shielding members 68 to 71 are arranged at the boundary positions, the dimming degree of each incident light incident on each point in the still exposure region ER2 is the center in the Y-axis direction (that is, the center point P1b). Is the smallest, and gradually increases with increasing distance from the center along the Y-axis direction. As a result, as shown in FIG. 11A, in the first pupil intensity distribution 61, the light intensities of the point light sources 78 constituting the first surface light source 61a and the second surface light source 61b are the light shielding members 68 to 71, respectively. Are hardly dimmed by each. Of course, in each point light source 78 constituting the third surface light source 61c and the fourth surface light source 61d, their light intensity is not dimmed by the light shielding members 68 to 71. That is, when the light shielding members 68 to 71 are arranged at the boundary positions, the properties of the first pupil intensity distribution 61 are hardly changed by the action of the light shielding members 68 to 71.

On the other hand, as shown in FIG. 11B, in the second pupil intensity distribution 62, the light intensity of some point light sources 78A among the point light sources 78 constituting the first surface light source 62a and the second surface light source 62b is as follows. The light is greatly reduced by the light shielding members 68 to 71, respectively. In other words, the first surface light source 62a and the second surface light source 62b are greatly dimmed by the light shielding action of the light shielding members 68 to 71, respectively. At this time, in each point light source 78 constituting the third surface light source 62c and the fourth surface light source 62d, the light intensity thereof is not dimmed by the light shielding members 68 to 71. In other words, when the light shielding members 68 to 71 are arranged at the boundary positions, the properties of the second pupil intensity distribution 62 are greatly changed by the action of the light shielding members 68 to 71. In FIGS. 11A and 11B, the point

light sources

78 and 78A are indicated by black circles (●). The size of these black circles indicates the intensity of light intensity for each of the point

light sources

78 and 78A, and the light intensity of the point light source 78A having a large black circle size is stronger than the light intensity of the small point light source 78A.

On the other hand, as shown in FIG. 12, when each of the light shielding members 68 to 71 is disposed at a position corresponding to the central portion of the effective lens surface in the Z-axis direction (hereinafter referred to as “central position”), The light shielding members 68 to 71 shield the exposure light EL to be incident on the central portion of the effective lens surface 77 in the Z-axis direction. On the other hand, each of the light shielding members 68 to 71 allows the exposure light EL to enter the both ends of the effective lens surface 77 in the Z-axis direction. At this time, the first surface light source of the first pupil intensity distribution 61 corresponding to the center point P1b of the still exposure region ER2 when most of the exposure light EL shielded by the light shielding members 68 to 71 is not shielded. It is the 1st incident light which forms 61a and the 2nd surface light source 61b. In addition, most of the exposure light EL that is not shielded by the light shielding members 68 to 71, the first surface light source 62a and the second surface light source of the second pupil intensity distribution 62 corresponding to the peripheral points P2b and P3b of the still exposure region ER2. Second incident light and third incident light forming 62b.

Therefore, when each of the light shielding members 68 to 71 is disposed at the center position, the dimming degree of each incident light incident on each point in the still exposure region ER2 is the center in the Y-axis direction (that is, the center point P1b). Is the largest, and gradually decreases with increasing distance from the center along the Y-axis direction. As a result, as shown in FIG. 13A, in the first pupil intensity distribution 61, the light intensity of a part of the point light sources 78A of the point light sources 78 constituting the first surface light source 61a and the second surface light source 61b is as follows. The light is greatly reduced by the light shielding members 68 to 71, respectively. In other words, the first surface light source 61a and the second surface light source 61b are greatly dimmed by the light shielding action of the light shielding members 68 to 71, respectively. At this time, in each point light source 78 constituting the third surface light source 61c and the fourth surface light source 61d, the light intensity thereof is not dimmed by the light shielding members 68 to 71. In other words, when the light shielding members 68 to 71 are arranged at the central positions, the properties of the first pupil intensity distribution 61 are greatly changed by the action of the light shielding members 68 to 71.

On the other hand, as shown in FIG. 13B, in the second pupil intensity distribution 62, the light intensities of the point light sources 78 constituting the first surface light source 62a and the second surface light source 62b are caused by the light shielding members 68 to 71, respectively. Each is hardly dimmed. Of course, in each point light source 78 constituting the third surface light source 62c and the fourth surface light source 62d, their light intensity is not dimmed by the light shielding members 68 to 71. That is, when the light shielding members 68 to 71 are arranged at the central positions, the properties of the second pupil intensity distribution 62 hardly change due to the action of the light shielding members 68 to 71.

Next, an example of an action when adjusting the

pupil intensity distributions

61 and 62 corresponding to the points P1b, P2b, and P3b along the Y-axis direction in the still exposure region ER2 will be described. In the initial state, each of the light shielding members 68 to 71 is assumed to be disposed outside the optical path of the exposure light EL.

Now, when the exposure light EL emitted from the light source device 12 is incident on the diffractive optical element 19, the diffractive optical element 19 emits the exposure light EL having a quadrilateral cross-sectional shape. Then, the exposure light EL passes through the correction filter 24 arranged at a position optically conjugate with the illumination pupil plane 27 or in the vicinity thereof. As a result, the illumination pupil plane 27 formed on the exit side of the optical integrator 26 is almost corrected by the correction filter 24 and the first and second

surface light sources

60a and 60b corrected (dimmed) by the correction filter 24. A secondary light source 60 having a third surface light source 60c and a fourth surface light source 60d that are not formed is formed. At this time, the pupil intensity distribution of the pupil conjugate plane optically conjugate with the illumination pupil plane 27 is also corrected by the correction filter 24.

Note that the correction filter 24 of the present embodiment reduces the light intensity of the third surface light source 60c and the fourth surface light source 60d along the Z-axis direction of the secondary light source 60 formed on the illumination pupil plane 27. It is a filter. As described above, in the first pupil intensity distribution 61 corresponding to the center points P1a and P1b in the illumination area ER1 of the reticle R and in the static exposure area ER2 on the wafer W, the correction filter is included in the optical path of the exposure light EL. 24, the light intensity of the first surface light source 61a and the second surface light source 61b along the X-axis direction is greater than the light intensity of the third surface light source 61c and the fourth surface light source 61d along the Z-axis direction. Are also weak. Therefore, in the first pupil intensity distribution 61, the light intensity of the third surface light source 61c and the fourth surface light source 61d is approximately equal to the light intensity of each of the first surface light source 61a and the second surface light source 61b by the correction filter 24. It becomes. On the other hand, in the second pupil intensity distribution 62 corresponding to the peripheral points P2a, P2b, P3a, and P3b in the illumination area ER1 and the still exposure area ER2, the X axis is used when the correction filter 24 is not in the optical path of the exposure light EL. Each light intensity of the first surface light source 62a and the second surface light source 62b along the direction is stronger than each light intensity of the third surface light source 62c and the fourth surface light source 62d along the Z-axis direction. Therefore, in the second pupil intensity distribution 62, the difference between the light intensity of the first surface light source 61a and the second surface light source 62b and the light intensity of each of the third surface light source 62c and the fourth surface light source 62d is caused by the correction filter 24. On the contrary, it will become bigger.

In order to make the first pupil intensity distribution 61 and the second pupil intensity distribution 62 have substantially the same distribution, the light intensity of the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 is obtained. Is slightly dimmed, and the light intensity of the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 needs to be greatly dimmed. Therefore, in this embodiment, the pupil intensity distribution measuring device 36 measures the light intensity of the quadrupole pupil intensity distribution for each point in the still exposure region ER2 in the secondary light source 60 formed on the illumination pupil plane 27. Is done. Here, the first pupil intensity distribution 61 formed on the illumination pupil plane 27 by the first incident light, the second incident light, and the third incident light incident on the center point P1b and the peripheral points P2b, P3b in the still exposure region ER2. The second pupil intensity distribution 62 is measured. In this case, the first pupil intensity distribution 61 and the second pupil intensity distribution 62 have different properties. Therefore, the light shielding members 68 to 71 are arranged in the optical path of the exposure light EL incident on the optical integrator 26 by driving the advance / retreat mechanism. At this time, the light shielding members 68 to 71 are arranged at the central positions.

Then, the light intensities of the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 are greatly reduced by the light shielding members 68 to 71, respectively. On the other hand, the light intensities of the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 are hardly dimmed by the light shielding members 68 to 71, respectively (see FIGS. 13A and 13B). ). Therefore, the difference between the property of the first pupil intensity distribution 61 and the property of the second pupil intensity distribution 62 is conversely larger than before the light shielding members 68 to 71 are arranged in the optical path of the exposure light EL. turn into.

Therefore, in the present embodiment, when the first driving force is applied to the light shielding members 68 to 71 from the moving mechanism 72 by the driving of the driving sources 73 to 76, the light shielding members 68 to 71 are moved in the Z-axis direction. Move each one. Then, of the first incident light to be incident on the first surface light source 67a and the second surface light source 67b, the amount of light shielded by the light shielding members 68 to 71 is arranged at the central position. Less than if On the other hand, of the second incident light and the third incident light to be incident on the first surface light source 67a and the second surface light source 67b, the light amounts shielded by the light shielding members 68 to 71 are respectively arranged at the central positions. It will be much larger than the case.

When each of the light shielding members 68 to 71 reaches the boundary position, each of the light shielding members 68 to 71 attempts to pass through the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 with respect to the center point P1b of the still exposure region ER2. The amount of the first incident light is only slightly attenuated by the light shielding members 68-71. That is, in the first pupil intensity distribution 61, each light intensity of the first surface light source 61a and the second surface light source 61b is compared with the case where the light shielding members 68 to 71 are not arranged in the optical path of the exposure light EL. Are slightly weakened, and the light intensity of the third surface light source 61c and the fourth surface light source 61d does not change. Further, when each of the light shielding members 68 to 71 is disposed at the boundary position, it tries to pass through the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 with respect to the peripheral point P2b of the still exposure region ER2. The amount of the second incident light to be reduced is greatly reduced by the light shielding members 68-71. Similarly, the light amounts of the third incident lights to be incident on the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 with respect to the peripheral point P3b of the still exposure region ER2 are the light shielding members 68 to 71, respectively. Greatly dimmed. That is, in each second pupil intensity distribution 62, each of the first surface light source 62a and the second surface light source 62b is compared with the case where the light shielding members 68 to 71 are not arranged in the optical path of the exposure light EL. As the light intensities become significantly weaker, the light intensities of the third surface light source 62c and the fourth surface light source 62d do not change.

As a result, the properties of the first pupil intensity distribution 61 and the properties of the second pupil intensity distribution 62 are substantially identical to each other. That is, the light intensity of each first incident light incident on the center point P1b of the stationary exposure region ER2 from each surface light source 61a to 61d and the light incident on each peripheral point P2b and P3b of the stationary exposure region ER2 from each surface light source 62a to 62d. The light intensity of each of the second incident light and each of the third incident light is substantially the same light intensity. Therefore, when the exposure process is executed in this state, the

pupil intensity distributions

61 and 62 corresponding to the points P1b, P2b, and P3b along the Y-axis direction in the static exposure region ER2 on the wafer W are substantially identical. Therefore, the occurrence of variations in the line width of the pattern formed on the surface Wa of the wafer W is suppressed.

Therefore, in this embodiment, the following effects can be obtained.
(1) A part of the exposure light EL that is to be incident on a part of the cylindrical lens surfaces 52 of each cylindrical lens surface 52 of the first micro fly's eye lens 50 is shielded by the light shielding unit 66. Due to the light shielding action by the light shielding unit 66, the

pupil intensity distributions

61 and 62 corresponding to the respective points on the surface Wa on the wafer W are independently adjusted. Therefore, the light intensity distribution at each point on the wafer W can be adjusted to distributions having substantially the same properties.

(2) In the present embodiment, each point P1b˜ in the static exposure region ER2 on the wafer W is located at a position optically conjugate with the surface Wa of the wafer W on the light source device 12 side of the optical integrator 26. A correction filter 24 is provided for uniformly adjusting the

pupil intensity distributions

61 and 62 corresponding to P3b. The

pupil intensity distributions

61 and 62 corresponding to the points P1b to P3b in the still exposure region ER2 are adjusted to be substantially uniform by the cooperation of the correction filter 24 and the light shielding unit 66. Therefore, the

pupil intensity distributions

61 and 62 corresponding to the points P1b to P3b in the still exposure region ER2 can be adjusted with higher precision than when the correction filter 24 is not arranged in the optical path of the exposure light EL. Therefore, it is possible to perform exposure processing on the wafer W under an appropriate illumination condition according to the circuit pattern of the reticle R. As a result, the wafer W is faithfully provided with a pattern having a desired line width over the entire wafer W. Can be formed.

(3) The light shielding part 66 of the present embodiment includes a plurality of light shielding members 68 to 71 extending along the X-axis direction. Then, by disposing the light shielding members 68 to 71 in the optical path of the exposure light EL, the pupil intensity distribution 61 corresponding to the points P1b to P3b along the Y-axis direction among the points in the still exposure region ER2. , 62 can be adjusted respectively.

(4) If each of the light shielding members 68 to 71 has a configuration that does not satisfy the conditional expression (Equation 1), each light shielding member 68 to 71 is placed in each effective lens surface 77 in the optical path of the exposure light EL. There is a possibility that there is an effective lens surface where the exposure light EL is not incident at all. In such a case, the

pupil intensity distributions

61 and 62 corresponding to all the points P1b to P3b in the still exposure region ER2 are uniformly changed. In other words, the

pupil intensity distributions

61 and 62 corresponding to the points P1b to P3b in the still exposure region ER2 cannot be adjusted independently. In this regard, in the present embodiment, each of the light shielding members 68 to 71 is configured to satisfy the conditional expression (Expression 1). Therefore, the exposure light EL always enters the effective lens surface 77 even if the light shielding members 68 to 71 are arranged in the optical path of the exposure light EL. Therefore, the

pupil intensity distributions

61 and 62 corresponding to the points P1b to P3b along the Y-axis direction in the still exposure region ER2 can be adjusted independently.

(5) Further, each of the light shielding members 68 to 71 is movable along the Y-axis direction and the Z-axis direction. Therefore, by moving the respective light shielding members 68 to 71 along the Y-axis direction and the Z-axis direction in the optical path of the exposure light EL, each point along the Y-axis direction among the points within the still exposure region ER2 is obtained. The

pupil intensity distributions

61 and 62 corresponding to P1b to P3b can be adjusted in high detail.

(6) In the present embodiment, the light shielding members 68 to 71 correspond to the measurement results calculated based on the detection signal from the pupil intensity distribution measuring device 36, that is, the points P1a to P3a in the illumination region ER1 of the reticle R. And move along the Z-axis direction based on the

pupil intensity distributions

61 and 62 respectively. For this reason, when the

pupil intensity distributions

61 and 62 change due to deterioration of at least one of the various optical elements constituting the illumination optical system 13, the light shielding is performed according to the measurement result by the pupil intensity distribution measuring device 36. By moving the members 68 to 71 in the Y-axis direction and the Z-axis direction, the

pupil intensity distributions

61 and 62 can be quickly adjusted so that their property distributions become the desired property distributions. .

(7) On the incident side of each cylindrical lens surface 52, a plurality of light shielding members 68 to 71 extending along the X-axis direction corresponding to the scanning direction of the wafer W and the reticle R at the time of exposure are arranged. Each of the light shielding members 68 to 71 adjusts the amount of exposure light EL incident on the effective lens surface 77 of each cylindrical lens surface 54 to thereby adjust the Y axis direction among the points in the still exposure region ER2. The

pupil intensity distributions

61 and 62 corresponding to the along points P1b to P3b can be adjusted.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment differs from the first embodiment in the configuration and arrangement position of the distribution correction unit. Therefore, in the following description, parts different from those of the first embodiment will be mainly described, and the same or corresponding member configurations as those of the first embodiment are denoted by the same reference numerals, and redundant description will be omitted. Shall.

As shown in FIG. 14, the distribution correction unit 31 </ b> A according to the present embodiment is configured so that the exposure light EL incident on the effective lens surface 77 among the cylindrical lens surfaces 54 formed on the exit surface 50 b of the first micro fly's eye lens 50. A light blocking part 66A is provided as a light reducing part for reducing the light intensity.

On the exit surface 50b side of the first micro fly's eye lens 50, an accommodation groove 86 extending along the X-axis direction is formed at a boundary portion between the effective lens surfaces 77 adjacent to each other in the Z-axis direction. In the present embodiment, of the effective lens surfaces 77 for forming the first surface light source 60a and the second surface light source 60b on the illumination pupil surface 27, the boundary portion between the effective lens surfaces 77 adjacent to each other in the Z-axis direction. Each is formed with a receiving groove 86. Each of the receiving grooves 86 is formed so as to extend from the end on the + X direction side of the first micro fly's eye lens 50 to the end on the −X direction side.

The light shielding portion 66A includes a plurality of (two in FIG. 13) square columnar light shielding members 87 as light reducing members extending along the X-axis direction. Each of these light shielding members 87 is formed such that the width D, which is the length in the Z-axis direction, and the length L in the Y-axis direction satisfy the conditional expression (Formula 1). Further, the length of each light shielding member 87 in the X-axis direction is equal to or longer than the width of the first micro fly's eye lens 50 in the X-axis direction.

Further, each light shielding member 87 is provided in the light shielding portion 66A between each housing groove 86 individually corresponding to each light shielding member 87 and outside the optical path of the exposure light EL (that is, outside the first micro fly's eye lens 50). An advancing / retreating device (not shown) is provided for advancing and retracting between them. When the light shielding member 87 is inserted into each housing groove 86 by the driving force from the advance / retreat apparatus, each light shielding member 87 is included in the effective lens surface 77 of the exposure light EL to be incident on the effective lens surface 77. The exposure light EL to be incident on both end portions in the Z-axis direction is shielded. In this case, most of the exposure light EL shielded by each light shielding member 87 is emitted from the illumination pupil plane 27 in a state having a predetermined angle with respect to the optical axis AX of the illumination optical system 13 when not shielded. The light that is That is, when most of the exposure light EL is not shielded, the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 corresponding to the peripheral points P2b and P3b of the still exposure region ER2. Are the second incident light and the third incident light. Further, most of the exposure light EL that is not shielded by each light shielding member 87 is light emitted from the illumination pupil plane 27 along the optical axis AX of the illumination optical system 13. That is, the exposure light EL is first incident light that forms the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 corresponding to the center point P1b of the still exposure region ER2.

Therefore, the light quantity of each first incident light that attempts to pass through the first surface light source 61a and the second surface light source 61b of the first pupil intensity distribution 61 with respect to the center point P1b of the still exposure region ER2 is slightly decreased by each light shielding member 87. It is only dimmed. That is, in the first pupil intensity distribution 61, each light intensity of the first surface light source 61a and the second surface light source 61b is different from that in the case where each light shielding member 87 is not disposed in the optical path of the exposure light EL. The light intensity of each of the third surface light source 61c and the fourth surface light source 61d does not change as it becomes slightly weaker. On the other hand, the amount of each second incident light that attempts to pass through the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 with respect to the peripheral point P2b of the still exposure region ER2 is greatly increased by each light shielding member 87. Dimmed. Similarly, the amount of each third incident light that is to enter the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 with respect to the peripheral point P3b of the still exposure region ER2 is greatly increased by each light shielding member 87. It will be fading. That is, in each second pupil intensity distribution 62, each light intensity of the first surface light source 62a and the second surface light source 62b is higher than when each light shielding member 87 is not disposed in the optical path of the exposure light EL. Each of the light sources of the third surface light source 62c and the fourth surface light source 62d does not change. As a result, the properties of the first pupil intensity distribution 61 and the properties of the second pupil intensity distribution 62 are substantially the same.

Therefore, in this embodiment, in addition to the effects (1) to (3) and (7) in the first embodiment, the following effects can be obtained.
(8) On the incident side of each cylindrical lens surface 54, a plurality of light shielding members 87 extending along the X-axis direction are arranged. These light shielding members 87 are arranged along the Y-axis direction among the respective points in the still exposure region ER2 by adjusting the amount of exposure light EL incident on the effective lens surface 77 of each cylindrical lens surface 54. The

pupil intensity distributions

61 and 62 corresponding to the points P1b to P3b can be adjusted.

(9) The light blocking member 87 of the present embodiment can be arranged in both the optical path of the exposure light EL that forms the first surface light source 67a and the optical path of the exposure light EL that forms the second surface light source 67b. Therefore, when the light intensity of the first surface light source 62a and the second surface light source 62b of the second pupil intensity distribution 62 is weakened, it is not necessary to provide a light shielding member for each surface light source. That is, the light shielding member for the first surface light source can be used for the second surface light source. Therefore, compared to the case of the first embodiment, it is possible to contribute to a reduction in the number of parts of the distribution correction unit 31A.

In addition, you may change each said embodiment into another embodiment as follows.
In each embodiment, the diffractive optical element 19 may be a diffractive optical element for multipole illumination (for example, for quadrupole illumination) or a diffractive optical element for annular illumination. In addition, if the optical element can change the shape of the exposure light EL, another arbitrary optical element such as an axicon lens pair is arranged instead of or in addition to the diffractive optical element 19. May be. An illumination optical system including an axicon lens pair is disclosed in, for example, International Publication No. 2005 / 076045A1 and corresponding US Patent Application Publication No. 2006 / 0170901A. In the embodiment shown in FIG. 1, an axicon lens pair can be disposed in the vicinity of the correction filter 24.

Further, instead of the diffractive optical element 19, for example, it is composed of a large number of minute element mirrors arranged in an array and whose inclination angle and inclination direction are individually controlled to divide the incident light beam into minute units for each reflecting surface. Thus, a spatial light modulation element that converts the cross section of the light beam into a desired shape or a desired size by deflecting the light beam may be used. An illumination optical system using such a spatial light modulator is disclosed in, for example, Japanese Patent Application Laid-Open No. 2002-353105.

In each embodiment, if the pupil intensity distribution measuring device 36 can measure the

pupil intensity distributions

61 and 62 corresponding to the points P1a, P2a, and P3a in the illumination area ER1 on the reticle R, It may not be near. However, the pupil intensity distribution measuring device 36 may be installed at an arbitrary position as long as it is in the vicinity of a position optically conjugate with the irradiated surface Ra of the reticle R (that is, the surface Wa of the wafer W).

In the first embodiment, the moving mechanism 72 may not be configured to be driven in conjunction with the measurement result by the pupil intensity distribution measuring device 36. That is, the measurement result of the pupil intensity distribution measuring device 36 is displayed on a display screen such as a monitor (not shown), and the operator moves the light shielding members 68 to 71 on the Y axis direction or the X axis based on the measurement result displayed on the display screen. You may make it move individually along a direction. In this case, the moving mechanism 72 does not have to be provided with the drive sources 73 to 76. That is, each of the light shielding members 68 to 71 is moved manually by the operator.

In the first embodiment, the

light shielding members

68 and 69 may be moved along the X-axis direction. For example, when the respective

light shielding members

68 and 69 are arranged at the boundary positions, when the light intensity of the first surface light source 62a of the second pupil intensity distribution 62 is to be slightly increased, as shown in FIG. At least one of the members 68 is moved to the + X direction side. Then, the respective amounts of the second incident light and the second incident light (exposure light EL) passing through the first surface light source 62a of the second pupil intensity distribution 62 are determined by the respective first light shielding members 68 in the optical path of the exposure light EL. This is less than before at least one displacement is performed.

In the first embodiment, the distribution correction unit 31 may be provided with an arbitrary number (for example, four) of first light shielding members other than two. Further, the distribution correction unit 31 may have a configuration in which an arbitrary number (for example, three) of second light shielding members other than two is provided.

Similarly, in the second embodiment, the distribution correction unit 31A may have a configuration in which an arbitrary number (for example, one) of light shielding members 87 other than two is provided.
In each embodiment, the installation positions of the light shielding members 68 to 71 and 87 may be fixed in the optical path of the exposure light EL. In this case, the light shielding members 68 to 71 and 87 are immovable.

In each embodiment, when exposure processing is performed while the wafer W and the reticle R are respectively scanned and moved along the Y-axis direction, a light shield extending along the Z-axis direction is formed on the incident side of the first micro fly's eye lens 50. A member may be provided. If comprised in this way, the pupil intensity distribution corresponding to each point in the X-axis direction substantially orthogonal to the scanning direction in the still exposure region ER2 can be adjusted.

In each embodiment, when the exposure process is performed while the wafer W and the reticle R are scanned and moved along the X-axis direction, the Z-axis is formed at the boundary portion of each incident surface 50a on the incident side of the first micro fly's eye lens 50. You may provide the light-shielding member extended along a direction. In this case, the light shielding member may be provided over the entire effective area (area through which the light beam can pass) of the first micro fly's eye lens 50. With this configuration, the illuminance distribution along the scanning direction (X-axis direction) of the illumination region ER1 in the reticle R can be changed to a trapezoidal illuminance distribution.

In each embodiment, the optical integrator 26 may be configured by a single micro fly's eye lens in which unit wavefront dividing surfaces having refractive power are arranged along the Z direction and the X direction. A fly-eye lens in which a plurality of lens elements are arranged may be used as the optical integrator. A pair of fly-eye mirrors in which a plurality of mirror surfaces are arranged may be used as the optical integrator.

In each embodiment, the exposure apparatus 11 may be embodied as a maskless exposure apparatus using a variable pattern generator (for example, DMD (Digital Mirror Device or Digital Mirror Micro-mirror Device)). Such a maskless exposure apparatus is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-304135, International Patent Publication No. 2006/080285, and US Patent Publication No. 2007/0296936 corresponding thereto.

In each embodiment, a method of filling the optical path between the projection optical system and the photosensitive substrate with a medium (typically liquid) having a refractive index larger than “1.1”, a so-called immersion method is applied. May be. In this case, as a method of filling the liquid in the optical path between the projection optical system and the photosensitive substrate, a method of locally filling the liquid as disclosed in International Publication No. WO99 / 49504, A method of moving a stage holding a substrate to be exposed as disclosed in Japanese Patent Laid-Open No. 6-124873 in a liquid bath, or a stage having a predetermined depth on a stage as disclosed in Japanese Patent Laid-Open No. 10-303114. A technique of forming a liquid tank and holding the substrate in the liquid tank can be employed.

In each embodiment, the polarization illumination method disclosed in US Patent Publication No. 2006/0203214, US Patent Publication No. 2006/0170901, and US Patent Publication No. 2007/0146676 may be applied.

In each embodiment, the exposure apparatus 11 manufactures a reticle or mask used in not only a microdevice such as a semiconductor element but also a light exposure apparatus, an EUV exposure apparatus, an X-ray exposure apparatus, and an electron beam exposure apparatus. Therefore, an exposure apparatus that transfers a circuit pattern from a mother reticle to a glass substrate or a silicon wafer may be used. The exposure apparatus 11 is used for manufacturing a display including a liquid crystal display element (LCD) and the like, and is used for manufacturing an exposure apparatus that transfers a device pattern onto a glass plate, a thin film magnetic head, and the like. It may be an exposure apparatus that transfers to a wafer or the like, and an exposure apparatus that is used to manufacture an image sensor such as a CCD.

In each embodiment, the exposure apparatus 11 may be embodied as a scanning stepper that transfers the pattern of the reticle R to the wafer W with the reticle R and the wafer W relatively moved, and sequentially moves the wafer W stepwise. .

In each embodiment, the light source device 12 includes, for example, g-line (436 nm), i-line (365 nm), KrF excimer laser (248 nm), F ₂ laser (157 nm), Kr ₂ laser (146 nm), Ar ₂ laser (126 nm) Or the like. The light source device 12 amplifies the infrared or visible single wavelength laser light oscillated from the DFB semiconductor laser or fiber laser, for example, with a fiber amplifier doped with erbium (or both erbium and ytterbium). Alternatively, a light source capable of supplying harmonics converted into ultraviolet light using a nonlinear optical crystal may be used.

In each embodiment, the exposure apparatus 11 may be embodied as an EUV exposure apparatus that uses extreme ultraviolet light that is a soft X-ray region having a wavelength of about 100 nm or less, that is, EUV (Extreme Ultraviolet light) as the exposure light EL. In this case, the exposure apparatus 11 includes a chamber whose interior is set to a vacuum atmosphere, and an illumination optical system 13, a reticle stage 14, a projection optical system 15, and a wafer stage 16 are disposed in the chamber. . In addition, the illumination optical system 13 and the projection optical system 15 are each composed of a reflective optical element, and the reticle R is a reflective reticle. The light shielding member is arranged on the light source side of the fly eye mirror located on the light source side of the pair of fly eye mirrors of the illumination optical system 13.

A unit in which the light shielding members 68 to 71, the moving mechanism 72, and the advance / retreat mechanism are integrated may be referred to as a dimming unit.
Next, an embodiment of a microdevice manufacturing method using the device manufacturing method by the exposure apparatus 11 of the embodiment of the present invention in the lithography process will be described. FIG. 16 is a flowchart illustrating a manufacturing example of a micro device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micro machine, or the like).

First, in step S101 (design step), function / performance design of a micro device (for example, circuit design of a semiconductor device) is performed, and a pattern design for realizing the function is performed. Subsequently, in step S102 (mask manufacturing step), a mask (reticle R or the like) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S103 (substrate manufacturing step), a substrate (a wafer W when a silicon material is used) is manufactured using a material such as silicon, glass, or ceramics.

Next, in step S104 (substrate processing step), using the mask and substrate prepared in steps S101 to S104, an actual circuit or the like is formed on the substrate by a lithography technique or the like as will be described later. Next, in step S105 (device assembly step), device assembly is performed using the substrate processed in step S104. Step S105 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary. Finally, in step S106 (inspection step), inspections such as an operation confirmation test and a durability test of the microdevice manufactured in step S105 are performed. After these steps, the microdevice is completed and shipped.

FIG. 17 is a diagram illustrating an example of a detailed process of step S104 in the case of a semiconductor device.
In step S111 (oxidation step), the surface of the substrate is oxidized. In step S112 (CVD step), an insulating film is formed on the substrate surface. In step S113 (electrode formation step), an electrode is formed on the substrate by vapor deposition. In step S114 (ion implantation step), ions are implanted into the substrate. Each of the above steps S111 to S114 constitutes a pretreatment process at each stage of the substrate processing, and is selected and executed according to a necessary process at each stage.

At each stage of the substrate process, when the above-described pretreatment process is completed, the posttreatment process is executed as follows. In this post-processing process, first, in step S115 (resist formation step), a photosensitive material is applied to the substrate. Subsequently, in step S116 (exposure step), the circuit pattern of the mask is transferred to the substrate by the lithography system (exposure apparatus 11) described above. Next, in step S117 (development step), the substrate exposed in step S116 is developed to form a mask layer made of a circuit pattern on the surface of the substrate. Subsequently, in step S118 (etching step), the exposed member other than the portion where the resist remains is removed by etching. In step S119 (resist removal step), the photosensitive material that has become unnecessary after the etching is removed. That is, in step S118 and step S119, the surface of the substrate is processed through the mask layer. By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the substrate.

Claims

An illumination optical system that illuminates the illuminated surface with light from a light source,
A plurality of incident side optical surfaces arranged in a plane intersecting with the optical axis of the illumination optical system, and arranged in a plane intersecting the optical axis on the irradiated surface side with respect to the plurality of incident side optical surfaces. And a plurality of exit-side optical surfaces individually corresponding to the plurality of entrance-side optical surfaces, and a predetermined light intensity distribution on an illumination pupil plane in the illumination optical path of the illumination optical system when light from the light source is incident An optical integrator that forms
A dimming unit disposed on the light source side of the plurality of incident side optical surfaces, and dimming part of light incident on at least some of the incident side optical surfaces of the plurality of incident side optical surfaces. ,
The dimming section has a longer length along the optical axis direction than a width along a first direction intersecting the optical axis direction of the illumination optical system in a plane intersecting the optical axis. An illumination optical system.
2. The illumination optical system according to claim 1, wherein the dimming unit diminishes a part of light incident on a part of the plurality of incident-side optical surfaces among the plurality of incident-side optical surfaces.
The said light reduction part has a light reduction member extended along the 2nd direction which cross | intersects the said 1st direction in the surface which cross | intersects the optical axis direction of the said illumination optical system. Item 3. The illumination optical system according to Item 2.
The light-reducing member has a length along the optical axis direction of the light-reducing member as L, a width along the first direction of the partial incident-side optical surface as D, and the partial incident. When the incident angle of light incident on the side optical surface is θ,
L <D / tan θ
The illumination optical system according to claim 3, wherein the following condition is satisfied.
The illumination optical system according to claim 3 or 4, further comprising a moving mechanism that moves the dimming member along the first direction on a plane intersecting the optical axis.
The illumination optical system according to any one of claims 3 to 5, further comprising a moving mechanism that moves the dimming member along the optical axis direction.
A measuring device for measuring a light intensity distribution in an angular direction of a light beam reaching a predetermined point on the irradiated surface;
The illumination optical system according to claim 5, further comprising a control device that drives the moving mechanism according to a measurement result by the measurement device.
The optical integrator is
A second surface is formed so as to extend along a third direction intersecting the optical axis direction of the illumination optical system in a plane intersecting the optical axis, and intersecting the third direction in a plane intersecting the optical axis. A plurality of first incident-side optical surfaces arranged along the direction of 4,
In the optical axis direction of the illumination optical system, the third optical surface is disposed at a position different from the plurality of first incident side optical surfaces, is formed to extend along the fourth direction, and is formed on the surface intersecting the optical axis. A plurality of second incident-side optical surfaces arranged along the direction of
In the optical axis direction, it is disposed closer to the irradiated surface than the plurality of first incident side optical surfaces, and extends along the third direction individually corresponding to the plurality of first incident side optical surfaces. A plurality of first emission-side optical surfaces that are formed and arranged along the fourth direction in a plane that intersects the optical axis;
In the optical axis direction, it is disposed closer to the irradiated surface than the plurality of second incident side optical surfaces, and extends along the fourth direction individually corresponding to the plurality of second incident side optical surfaces. 8. A plurality of second exit-side optical surfaces that are formed and arranged along the third direction in a plane that intersects the optical axis. The illumination optical system according to one item.
The optical integrator includes a first optical member disposed on the light source side in the optical axis direction, and a second optical member disposed on the irradiated surface side,
The plurality of first incident side optical surfaces are formed on the incident side of the first optical member, and the plurality of second incident side optical surfaces are formed on the emission side of the first optical member,
The plurality of first emission-side optical surfaces are formed on the incident side of the second optical member, and the plurality of second emission-side optical surfaces are formed on the emission side of the second optical member. The illumination optical system according to claim 8.
The dimming unit is disposed on the light source side of the plurality of first incident-side optical surfaces, and a part of light incident on some second incident-side optical surfaces of the plurality of second incident-side optical surfaces. The illumination optical system according to claim 8 or 9, wherein the illumination optical system is dimmed.
The dimming unit is disposed on the irradiated surface side with respect to the plurality of first incident side optical surfaces and at a position closer to the light source than the plurality of second incident side optical surfaces, and The illumination according to any one of claims 8 to 10, wherein a part of light incident on a part of the second incident-side optical surfaces of the second incident-side optical surfaces is dimmed. Optical system.
The dimming unit includes a dimming member that dims a part of light incident on all the incident side optical surfaces among the plurality of incident side optical surfaces and extends along the first direction. The illumination optical system according to any one of claims 1 to 11, wherein the illumination optical system is characterized in that:
Used in combination with a projection optical system that forms a surface optically conjugate with the irradiated surface,
The illumination optical system according to any one of claims 1 to 12, wherein the illumination pupil is formed at a position optically conjugate with an aperture stop of the projection optical system.
14. The light-attenuating unit is a light-shielding unit that shields a part of light incident on at least some of the incident-side optical surfaces among the plurality of incident-side optical surfaces. The illumination optical system as described in any one of them.
The illumination optical system according to any one of claims 1 to 14, wherein light output from a light source is guided to a predetermined pattern on the irradiated surface,
An exposure apparatus that projects an image of a pattern formed by illuminating the predetermined pattern with light emitted from the illumination optical system onto a substrate coated with a photosensitive material.
A projection optical system for projecting an image of the pattern onto the substrate;
16. The exposure apparatus according to claim 15, wherein an image of the pattern is projected onto the substrate by moving the pattern and the substrate relative to the projection optical system along a scanning direction.
An exposure step of exposing an image of the pattern onto the surface of the substrate using the exposure apparatus according to claim 15 or 16,
After the exposure step, the development step of developing the substrate to form a mask layer having a shape corresponding to the image of the pattern on the surface of the substrate;
And a processing step of processing the surface of the substrate through the mask layer after the developing step.
An illumination optical system that illuminates a surface to be irradiated with light from a light source, the plurality of incident-side optical surfaces arranged in a plane that intersects the optical axis of the illumination optical system, and the plurality of incident-side optical surfaces And a plurality of exit-side optical surfaces arranged in a plane intersecting the optical axis on the irradiated surface side and individually corresponding to the plurality of incident-side optical surfaces, and when light from the light source is incident A dimming unit combined with an illumination optical system including an optical integrator that forms a predetermined light intensity distribution on an illumination pupil plane in an illumination optical path of the illumination optical system,
A dimming unit disposed on the light source side of the plurality of incident-side optical surfaces of the optical integrator and dimming a part of light incident on at least some of the plurality of incident-side optical surfaces. With
The dimming section has a longer length along the optical axis direction than a width along a first direction intersecting the optical axis direction of the illumination optical system in a plane intersecting the optical axis. A dimming unit characterized by
The dimming unit according to claim 18, wherein the dimming unit dimmes a part of light incident on some of the incident side optical surfaces among the plurality of incident side optical surfaces.
The said light reduction part has a light reduction member extended along the 2nd direction which cross | intersects the said 1st direction in the surface which cross | intersects the optical axis direction of the said illumination optical system. Item 20. The dimming unit according to Item 19.
The light-reducing member has a length along the optical axis direction of the light-reducing member as L, a width along the first direction of the partial incident-side optical surface as D, and the partial incident. When the incident angle of light incident on the side optical surface is θ,
L <D / tan θ
The dimming unit according to claim 20, wherein the following condition is satisfied.
The dimming unit according to claim 20 or 21, further comprising a moving mechanism for moving the dimming member along the first direction on a plane intersecting the optical axis.
The dimming unit according to any one of claims 20 to 22, further comprising a moving mechanism that moves the dimming member along the optical axis direction.
The optical integrator is
A second surface is formed so as to extend along a third direction intersecting the optical axis direction of the illumination optical system in a plane intersecting the optical axis, and intersecting the third direction in a plane intersecting the optical axis. A plurality of first incident-side optical surfaces arranged along the direction of 4,
In the optical axis direction of the illumination optical system, the third optical surface is disposed at a position different from the plurality of first incident side optical surfaces, is formed to extend along the fourth direction, and is formed on the surface intersecting the optical axis. A plurality of second incident-side optical surfaces arranged along the direction of
In the optical axis direction, it is disposed closer to the irradiated surface than the plurality of first incident side optical surfaces, and extends along the third direction individually corresponding to the plurality of first incident side optical surfaces. A plurality of first emission-side optical surfaces that are formed and arranged along the fourth direction in a plane that intersects the optical axis;
In the optical axis direction, it is disposed closer to the irradiated surface than the plurality of second incident side optical surfaces, and extends along the fourth direction individually corresponding to the plurality of second incident side optical surfaces. A plurality of second exit-side optical surfaces that are formed and arranged along the third direction in a plane that intersects the optical axis,
The dimming unit is disposed on the light source side of the plurality of first incident-side optical surfaces, and a part of light incident on some second incident-side optical surfaces of the plurality of second incident-side optical surfaces. The dimming unit according to any one of claims 18 to 23, wherein the dimming unit is dimmed.
The optical integrator includes a first optical member disposed on the light source side in the optical axis direction, and a second optical member disposed on the irradiated surface side,
The plurality of first incident side optical surfaces are formed on the incident side of the first optical member, and the plurality of second incident side optical surfaces are formed on the emission side of the first optical member,
The plurality of first emission-side optical surfaces are formed on the incident side of the second optical member, and the plurality of second emission-side optical surfaces are formed on the emission side of the second optical member. The dimming unit according to claim 24.
The dimming unit is disposed on the irradiated surface side with respect to the plurality of first incident side optical surfaces and at a position closer to the light source than the plurality of second incident side optical surfaces, and The dimming unit according to claim 24 or 25, wherein a part of light incident on a part of the second incident side optical surfaces of the second incident side optical surfaces is dimmed.
The dimming unit includes a dimming member that dims a part of light incident on all the incident-side optical surfaces of the plurality of incident-side optical surfaces and extends along the first direction. The dimming unit according to any one of claims 18 to 26, characterized in that:
Used in combination with a projection optical system that forms a surface optically conjugate with the irradiated surface,
The dimming unit according to any one of claims 18 to 27, wherein the illumination pupil is formed at a position optically conjugate with an aperture stop of the projection optical system.
29. The light-attenuating unit is a light-shielding unit that shields part of light incident on at least some of the incident-side optical surfaces among the plurality of incident-side optical surfaces. The light reduction unit as described in any one of them.