JP2010177410A - Light shielding unit, illumination optical system, exposure apparatus, and method of manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light shielding unit capable of adjusting a light intensity distribution in an angle direction for each position on a surface to be irradiated, and to provide an illumination optical system, an exposure apparatus, and a method of manufacturing the device. <P>SOLUTION: The light shielding unit 47 is provided in the illumination optical system 13 for illuminating a surface Ra to be irradiated with exposure light EL emitted from a light source apparatus 12 through an optical integrator 28 to adjust the quantity of the light emitted from the light source apparatus 12. The light shielding unit 47 is provided with light shielding members 55 and 56 that are arranged closer to the side of the surface Ra to be irradiated than the optical integrator 28 in an optical path of the exposure light EL and formed in such a manner that the dimensions in the direction of the optical axis in the illumination optical system 13 differ for each position in the plane intersecting with the optical axis AX and a displacement mechanism for displacing the light shielding members 55 and 56 in the direction intersecting with the direction of the optical axis in the optical path of the exposure light EL. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light shielding unit that adjusts the amount of light emitted from a light source, an illumination optical system including the light shielding unit, an exposure apparatus including the illumination optical system, and a device manufacturing method using the exposure apparatus.

  In general, in an exposure apparatus for manufacturing a microdevice such as a semiconductor integrated circuit, light emitted from a light source is used as a substantial surface light source composed of a number of light sources via a fly-eye lens as an optical integrator. A secondary light source is formed. The secondary light source indicates a light intensity distribution (hereinafter referred to as “pupil intensity distribution”) at the illumination pupil. The illumination pupil is defined as a position that is optically Fourier-transformed with respect to the irradiated surface of the mask.

  Then, after the light from the secondary light source is collected by the condenser lens, the mask on which a predetermined pattern is formed is illuminated in a superimposed manner. Subsequently, the light transmitted through the mask forms an image on the wafer coated with the photosensitive material via the projection optical system, and the mask pattern is projected and exposed (transferred) onto the wafer.

  At this time, it is indispensable to obtain a uniform illuminance distribution on the wafer in order to accurately transfer the mask pattern formed on the mask. Therefore, conventionally, in order to accurately transfer the mask pattern onto the wafer, for example, an annular or multipolar (bipolar, quadrupolar, etc.) pupil intensity distribution is formed, and the depth of focus of the projection optical system is determined. A technique for improving the resolution has been proposed (see Patent Document 1).

US Patent Publication No. 2006/0055834

  By the way, when the mask pattern is faithfully transferred onto the wafer, the light intensity distribution (pupil intensity distribution) in the angular direction of the light beam irradiated to each point on the wafer as the final irradiated surface is determined at which point. It is necessary to adjust so that it becomes almost equal. However, as shown in Patent Document 1, in the conventional exposure apparatus, when the pupil intensity distribution varies at each point on the wafer, the variation in the pupil intensity distribution cannot be suppressed. For this reason, there is a possibility that the fine pattern of the mask cannot be faithfully transferred onto the wafer over the entire exposure area because the pattern varies at each position on the wafer.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a light-shielding unit, an illumination optical system, an exposure apparatus, and a device that can adjust the pupil intensity distribution for each position on the irradiated surface. It is in providing the manufacturing method of.

In order to solve the above-described problems, the present invention employs the following configuration corresponding to FIGS. 1 to 21 shown in the embodiment.
The light shielding unit of the present invention is provided in the illumination optical system (13) that illuminates the irradiated surface (Ra) with the light (EL) emitted from the light source (12) via the optical integrator (28), and In the light-shielding unit (28) that adjusts the light intensity distribution in the angular direction of the light flux reaching the surface (Ra), it is closer to the irradiated surface (Ra) than the optical integrator (28) in the optical path of the light (EL). A light shielding member (55, 56) that is arranged and configured so that the dimension in the optical axis direction of the illumination optical system (13) is different for each position in a plane intersecting the optical axis (AX); The gist is provided with a displacement mechanism (58) capable of displacing the member (55, 56) in a direction intersecting the optical axis direction in the optical path of the light (EL).

  According to the above configuration, the displacement mechanism is configured so that the dimension in the optical axis direction of the illumination optical system differs according to the incident position when the light emitted from the light source enters the light shielding member. Is displaced. Therefore, due to the displacement of the light shielding member, the amount of change in the light shielding amount by which the light emitted from the light source is shielded by the light shielding member differs depending on the position on the irradiated surface where the light is incident. Therefore, the displacement mechanism can independently adjust the light intensity, particularly the light intensity distribution in the angular direction, at each position on the irradiated surface by displacing the light shielding member in the optical path.

  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 shown in the embodiments, but it goes without saying that the present invention is not limited to the embodiments.

  According to the present invention, it is possible to adjust the light intensity at each position on the irradiated surface, particularly the light intensity distribution in the angular direction.

1 is a schematic block diagram that shows an exposure apparatus of a first embodiment. 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 exposure 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 exposure light which injects into the peripheral point in a still exposure area | region. The schematic side view which shows the light-shielding unit of 1st Embodiment. The schematic plan view which shows the light-shielding unit of 1st Embodiment. (A) is a schematic diagram showing a state in which exposure light emitted from approximately the center of each surface light source is incident on the center point in the illumination area, and (b) is illumination light exposed from approximately the center of each surface light source. The schematic diagram which shows the state which injected into the peripheral point in an area | region, (c) is a schematic front view which shows each point on the virtual surface through which the exposure light inject | emitted from the approximate center of each surface light source passes. The block diagram which shows the control apparatus of 1st Embodiment. The schematic diagram which shows the effect | action of the light-shielding unit with respect to the exposure light inject | emitted toward the center point and peripheral point in an illumination area from each surface light source. The schematic plan view which shows the state which each light-shielding member which comprises the light-shielding unit of 1st Embodiment relatively moved to the Y-axis direction. The graph which shows distribution of the thickness in the optical axis direction of the illumination optical system along the Y-axis direction of the light shielding unit of the state shown in FIG. (A) is a schematic diagram showing an effect on the exposure light of the light shielding unit in a state where the dimension of the illumination optical system in the optical axis direction is relatively large, and (b) is a relatively small dimension in the optical axis direction of the illumination optical system. The schematic diagram which shows the effect | action with respect to the exposure light of the light-shielding unit of a state. FIG. 6 is a schematic block diagram that shows an exposure apparatus of a second embodiment. The schematic side view which shows the light-shielding unit of 2nd Embodiment. The schematic plan view which shows the light-shielding unit of 2nd Embodiment. (A) is a schematic diagram showing the action of the light shielding unit on the exposure light emitted toward the center point of the opening of the reticle blind, and (b) is the exposure light emitted toward the peripheral point of the opening of the reticle blind. The schematic diagram which shows the effect | action of the light-shielding unit with respect to. The schematic plan view which shows the state which each light-shielding member which comprises the light-shielding unit of 2nd Embodiment relatively moved to the X-axis direction. (A) is a schematic diagram showing the action of the light shielding unit on the exposure light emitted toward the center point of the opening of the reticle blind, and (b) is the exposure light emitted toward the peripheral point of the opening of the reticle blind. The schematic diagram which shows the effect | action of the light-shielding unit with respect to. The flowchart of the manufacture example of a device. The detailed flowchart regarding the board | substrate process in the case of a semiconductor device.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the Z-axis direction is parallel to the optical axis of the projection optical system 15 (to be described later) (the vertical direction in FIG. 1), the Y-axis direction is the horizontal direction in FIG. It is assumed that the X-axis direction is set in a direction orthogonal to each other.

  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 (a surface on the + Z direction side, 1 is a device for projecting an image of a circuit pattern onto a wafer W as a photosensitive substrate having a photosensitive material such as a resist coated on the upper surface in FIG. Such an exposure apparatus 11 includes an illumination optical system 13 that guides exposure light EL emitted from a light source device 12 as a light source to an irradiated surface Ra (a surface on the + Z direction side) of the reticle R, and a reticle stage 14 that holds the reticle R. A projection optical system 15 that guides the exposure light EL transmitted through the reticle R to the irradiated surface Wa of the wafer W, and a wafer stage 16 that holds the wafer W. 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). On the exit side (reticle R side) of the first reflecting mirror 18, a diffractive optical element 19 is provided as an optical element for adjusting the irradiation mode of the exposure light EL on the irradiated surface Ra of the reticle R. 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 polarizations 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 enters. 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 afocal optical system 20 is arranged on the optical path of the exposure light EL so that the focal position on the incident side and the installation position of the diffractive optical element 19 substantially coincide.

  Further, in the optical path between the first lens group 21 and the second lens group 22, the transmittance is at a position optically conjugate with an incident surface of an optical integrator 28, which will be described later, according to the incident position of the exposure light EL. A correction filter 24 having different transmittance distributions is provided. The correction filter 24 is a filter in which a light-shielding dot composed of chromium (Cr), chromium oxide (CrO), or the like is formed on an incident surface of a flat glass substrate.

  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 27 is provided, and the zoom optical system 27 is disposed on the exit side of a predetermined surface 23 (indicated by a broken line in FIG. 1) located at the focal position on the exit side of the afocal optical system 20. . The exposure light EL emitted from the zoom optical system 27 is converted into a parallel light beam by the zoom optical system 27 and then enters the optical integrator 28 disposed on the emission side of the zoom optical system 27. ing. Then, the optical integrator 28 divides the incident exposure light EL into a plurality of light fluxes, and divides the wavefront into a plurality of light fluxes. .). Note that the illumination pupil plane 29 on which the pupil intensity distribution is formed is also referred to as a secondary light source 30 including a large number of surface light sources.

  The optical integrator 28 has an incident surface (a surface on the −Y direction side and a left surface in FIG. 1) located at the focal position (also referred to as pupil plane) on the exit side of the zoom optical system 27 or in the vicinity of the focal position. Are arranged as follows. That is, in the zoom optical system 27, the predetermined surface 23 and the incident surface of the optical integrator 28 are substantially in a Fourier transform relationship, and the focal position on the exit side of the afocal optical system 20 and the incident surface of the optical integrator 28 are Are arranged at positions that are optically nearly conjugate.

  On the exit side of the optical integrator 28, an illumination aperture stop (not shown) is disposed at a position optically conjugate with the entrance pupil plane of the projection optical system 15 and defines a range that contributes to illumination of the secondary light source 30. 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 30 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 30 is an annular shape, the illumination aperture stop is driven so that an opening having a shape corresponding to the annular shape is located in the optical path of the exposure light EL. Is done. Further, when the cross-sectional shape of the exposure light EL emitted from the secondary light source 30 is a quadrupole shape, the illumination aperture stop is configured so that the opening corresponding to the quadrupole shape is positioned in the optical path of the exposure light EL. Driven by.

  A first condenser optical system 31 including at least one optical element (only one is shown in FIG. 1) having power (reciprocal of focal length) is provided on the exit side of the optical integrator 28 and the illumination aperture stop. It has been. 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, on the exit side of the first condenser optical system 31 and at a position optically conjugate with the irradiated surface Ra of the reticle R and the irradiated surface Wa of the wafer W, it is also referred to as a reticle blind 33 (also referred to as “mask blind”). .) Is provided. The reticle blind 33 is formed with a rectangular opening 34 whose longitudinal direction is the Z-axis direction and whose transverse direction is the X-axis direction. The exposure light EL emitted from the first condenser optical system 31 illuminates the reticle blind 33 in a superimposed manner.

  Further, a second condenser optical system 35 composed of a lens having power is provided on the exit side of the reticle blind 33, and the second condenser optical system 35 is provided with the exposure light EL incident from the reticle blind 33 side. Is converted into a substantially parallel light beam. A second reflecting mirror 37 is provided on the exit side of the second condenser optical system 35. Then, the exposure light EL emitted from the second condenser optical system 35 is reflected by the second reflecting mirror 37 toward the −Z direction side (the lower side in FIG. 1), and then on the emitting side of the second reflecting mirror 37. The light is incident on a lens group 38 composed of optical elements (lenses) having at least one (only one is shown in FIG. 1) power. The exposure light EL emitted from the lens group 38 illuminates the irradiated surface Ra of the reticle R in a superimposed manner.

  A predetermined surface 39 (shown by a broken line in FIG. 1) located in the vicinity of the entrance surface of the lens group 38 is optically conjugate with the illumination pupil plane 29, and the predetermined plane 39 includes the illumination pupil plane 29. A pupil intensity distribution having the same shape as the pupil intensity distribution formed above is formed. In this embodiment, the shape of the opening 34 of the reticle blind 33 is rectangular as described above. Therefore, in the illumination area ER1 on the reticle R and the static exposure area ER2 on the wafer W, as shown in FIGS. 3A and 3B, the longitudinal direction is the Y-axis direction and the short direction is the X-axis direction. Each is formed in a rectangular shape.

  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. 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 light shielding unit 47 that can adjust the light shielding amount for the exposure light EL emitted from the lens group 38 is between the lens group 38 and the reticle stage 14 and in the vicinity of the irradiated surface Ra of the reticle R. Is provided. Then, the light shielding unit 47 includes an illumination area ER1 (see FIG. 3A) formed on the reticle R and a static exposure area ER2 formed on the wafer W that is optically conjugate with the illumination area ER1. The light intensity at each point in (see FIG. 3B) can be adjusted.

  A pupil intensity distribution measuring device 40 is provided in the vicinity of the reticle stage 14. The pupil intensity distribution measuring device 40 is a device that measures the pupil intensity distribution formed by incident light incident on one point in the illumination area ER1 on the reticle R in the secondary light source 30 for each point (for each position). Such a pupil intensity distribution measuring apparatus 40 includes a beam splitter 41 that reflects a part of the exposure light EL emitted from the lens group 38 toward the reticle R, and a measurement light that is reflected by the reflected beam reflected by the beam splitter 41. A lens 42 and a detection unit 43 made of a CCD image pickup device, a photodiode, or the like, on which the reflected light emitted from the measurement lens 42 enters, are provided. The pupil intensity distribution measuring device 40 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 pupil intensity distribution measuring device 40 may be provided on the wafer stage 16 or a measurement stage independent of the wafer stage 16.

  The projection optical system 15 includes a lens barrel 44 filled with an inert gas such as nitrogen, and a plurality of lenses (not shown) are provided in the lens barrel 44 along the optical path of the exposure light EL. . Further, in the lens barrel 44, an aperture stop 45 is arranged at a position that is optically Fourier-transformed with an installation position of the irradiated surface Wa of the wafer W and an installation position of the irradiated surface Ra of the reticle R. Yes. Then, the image of the circuit pattern of 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 when the projection optical system 15 is used.

  The wafer stage 16 includes a planar placement surface 46 that is substantially orthogonal to the optical axis of the projection optical system 15, and the wafer W is placed on the placement surface 46. 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 irradiated surface Wa of the wafer W is orthogonal 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 (in FIG. From the side to the back side of the drawing) at every predetermined stroke. Then, the illumination area ER1 in 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. Further, 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.

  Here, when a diffractive optical element for annular illumination is used as the diffractive optical element 19, an annular illumination field centered on the optical axis AX of the illumination optical system 13 is formed on the incident side of the optical integrator 28. The As a result, an annular secondary light source 30 similar to the annular illumination field formed on the incident side is formed on the illumination pupil plane 29 located on the exit side of the optical integrator 28. When the diffractive optical element 19 for multipole illumination is used as the diffractive optical element 19, a plurality of predetermined shapes (arc-shaped, centered on the optical axis AX of the illumination optical system 13 are formed on the incident side of the optical integrator 28. A multipolar illumination field consisting of a circular illumination field is formed. As a result, a multipolar secondary light source 30 is formed on the illumination pupil plane 29 located on the exit side of the optical integrator 28, 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 29 positioned on the exit side of the optical integrator 28, as shown in FIG. 2, four arc-shaped substantial surface light sources (hereinafter simply referred to as “surface light sources”) 50a to 50d. A quadrupolar secondary light source 30 (pupil intensity distribution) is formed. Specifically, the secondary light source 30 includes an arc-shaped first surface light source 50a 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. It has an arcuate second surface light source 50b positioned, and the distance between the first surface light source 50a and the optical axis AX is substantially equal to the distance between the second surface light source 50b and the optical axis AX. Yes. Further, the secondary light source 30 is an arcuate third surface light source 50c 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 arc-shaped fourth surface light source 50d is provided, and the distance between the third surface light source 50c and the optical axis AX is substantially equal to the distance between the fourth surface light source 50d and the optical axis AX.

  When each exposure light EL emitted from each of the surface light sources 50a, 50b, 50c, 50d is guided onto the reticle R, as shown in FIG. A rectangular illumination region ER1 in which the direction is the Y-axis direction and the short direction is the X-axis direction is formed. Further, on the irradiated surface Wa of the wafer W, a rectangular still exposure region ER2 corresponding to the illumination region ER1 on the reticle R is formed as shown in FIG. 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, each of the incident quadrupole pupil intensity distributions incident on each point in the still exposure area ER2 (and the illumination area ER1) depends on the position where the exposure light EL is incident, and the light intensity distribution in the angular direction. Tend to be different from each other.

  Specifically, as shown in FIGS. 3A, 3B, and 4, it is formed by exposure light EL that is incident on center points P1a and P1b in the Y-axis direction in the illumination region ER1 and in the static exposure region ER2. In the first pupil intensity distribution 51, the light intensity of the third surface light source 51c and the fourth surface light source 51d arranged along the Z-axis direction is the first surface light source 51a arranged along the X-axis direction. And it tends to be stronger than the light intensity of the second surface light source 51b. On the other hand, as shown in FIGS. 3 (a), 3 (b) and 5, each peripheral point P2a, spaced along the Y-axis direction with respect to the center points P1a, P1b in the illumination region ER1 and the still exposure region ER2. In the second pupil intensity distribution 52 formed by the exposure light EL incident on P2b, the light intensity of the third surface light source 52c and the fourth surface light source 52d arranged along the Z axis direction is more in the X axis direction. There exists a tendency for it to become weaker than the light intensity of the 1st surface light source 52a arrange | positioned along with the 2nd surface light source 52b. The pupil intensity distributions 51 and 52 referred to here are the illumination pupil plane 29 and the illumination pupil when the correction filter 24 and the light shielding unit 47 are not arranged in the optical path of the exposure light EL in the illumination optical system 13. The light intensity distribution corresponding to the points P1b and P2b in the still exposure region ER2 formed on a pupil conjugate plane (for example, the predetermined plane 39) optically conjugate with the plane 29 is shown.

Next, the light shielding unit 47 of the present embodiment will be described with reference to FIGS.
6 and 7, the light shielding unit 47 illuminates the third surface light sources 51c and 52c and the fourth surface light sources 51d and 52d in the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. A plurality of (two in this embodiment) light shielding members 55 and 56 arranged in parallel along the Z-axis direction so as to face each other in the optical axis direction of the optical system 13 are provided so as to be freely displaceable in the Y-axis direction. ing. Of the light shielding members 55 and 56, the first light shielding member 55 arranged on the + Z direction side has a surface 55a on the + Z direction side (the lens group 38 side), and the YZ plane having the optical axis AX as the Z coordinate axis. It is configured to have a curved surface shape defined by a third power series with respect to the Y axis, and has a shape extending in the Y axis perpendicular to the scanning direction (X axis direction). Yes. On the other hand, the second light shielding member 56 arranged on the −Z direction side has a surface 56a on the −Z direction side (reticle stage 14 side) with respect to the Y axis in the YZ plane with the optical axis AX as the Z coordinate axis. And has a shape extending in the Y axis orthogonal to the scanning direction (X axis direction). The light shielding members 55 and 56 are such that the surfaces 55b and 56b adjacent to each other in the Z-axis direction have a rectangular planar shape along the Y-axis direction and face each other with a slight clearance. It is configured.

  Specifically, the first light shielding member 55 has a thickness Z1, which is a distance between the surfaces 55a and 55b in the Z-axis direction, with respect to the coordinate Y in the Y-axis direction with the optical axis AX as the Z-coordinate axis. This is expressed by Formula 1.

[Formula 1]
Z1 = aY ³ + bY + c
Similarly, the second light shielding member 56 has a thickness Z2, which is a distance between the surface 56a and the surface 56b in the Z-axis direction, with respect to the coordinate Y in the Y-axis direction with the optical axis AX as the Z-coordinate axis. It is represented by Formula 2.

[Formula 2]
Z2 = −aY ³ −bY + c
Therefore, as shown in FIG. 7, the thickness Za in the Z-axis direction of the light-blocking unit 47 in the facing state (the state before displacement) in which the first light-blocking member 55 and the second light-blocking member 56 are aligned with each other in the Y-axis direction. Is represented by Equation 3.

[Formula 3]
Za = Z1 + Z2 = 2c
That is, in the light shielding unit 47, when the first light shielding member 55 and the second light shielding member 56 are in the opposed positions shown in FIG. 7, the thickness Z1 of the first light shielding member 55 and the second light shielding at each position in the Y-axis direction. The sum of the member 56 and the thickness Z2 is a constant thickness (Za = Z1 + Z2 = 2c).

  Here, as shown in FIG. 8A, the exposure light EL (that is, the reticle R) emitted from the surface light sources 51a, 51b, 51c, 51d of the first pupil intensity distribution 51 formed on the predetermined surface 39. An XY plane (hereinafter referred to as a virtual plane 57) through which the exposure light EL emitted toward the center points P1a and P1b in the illumination area ER1 and the stationary exposure area ER2 passes through the approximate center of the light shielding unit 47. Let each point which cross | intersect be point A1, B1, C1, D1. In this case, as shown in FIG. 8C, the point A1 is located on the + X direction side of the optical axis AX of the illumination optical system 13, and the point B1 is the -X direction of the optical axis AX of the illumination optical system 13. Located on the side. The distance between the point A1 and the optical axis AX is substantially equal to the distance between the point B1 and the optical axis AX. The point C1 is located on the + Y direction side of the optical axis AX of the illumination optical system 13, and the point D1 is located on the −Y direction side of the optical axis AX of the illumination optical system 13. The distance between the point C1 and the optical axis AX is substantially equal to the distance between the point D1 and the optical axis AX.

  Further, as shown in FIG. 8B, the exposure light EL (that is, the reticle R of the reticle R) emitted from the surface light sources 52a, 52b, 52c, and 52d of the second pupil intensity distribution 52 formed on the predetermined surface 39. Points A2, B2, C2, and D2 are points at which the exposure light EL) emitted toward the points P2a and P2b in the illumination region ER1 and the static exposure region ER2 intersects the virtual plane 57. In this case, as shown in FIG. 8C, the points A2, B2, C2, and D2 are arranged at positions shifted to the + Y direction side with respect to the corresponding points A1, B1, C1, and D1, respectively. ing. That is, the light shielding unit 47 has a position intersecting the exposure light EL emitted from the surface light sources 51 a, 51 b, 51 c, 51 d of the first pupil intensity distribution 51 on the predetermined surface 39 and the first surface on the predetermined surface 39. The positions of the two-pupil intensity distribution 52 that intersect the exposure light EL emitted from the surface light sources 52a, 52b, 52c, and 52d are different from each other in the Y-axis direction orthogonal to the optical axis AX of the illumination optical system 13. It has become a relationship. And in the light-shielding unit 47 of this embodiment, as represented by Formula 3, at each point A1, A2, B1, B2, C1, C2, D1, D2 where the positions in the Y-axis direction are different, Z The axial thicknesses are the same.

  The light shielding unit 47 is provided with a displacement mechanism 58 (see FIG. 9) for individually displacing the light shielding members 55 and 56. As shown in FIG. 9, the displacement mechanism 58 includes a plurality (two in this embodiment) of driving sources 59 corresponding to the respective light shielding members 55 and 56 individually. These drive sources 59 are emitted from the surface light sources 51 a to 51 d and 52 a to 52 d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39 in accordance with a control command from the control device 60. In the optical path of the exposure light EL, the corresponding light shielding members 55 and 56 are displaced along the Y-axis direction.

Next, the control configuration of the exposure apparatus 11 of the present embodiment will be described.
As shown in FIG. 9, a control device 60 for controlling the driving state of the entire apparatus in the exposure apparatus 11 includes a controller (not shown) having a CPU and the like, and a drive circuit (not shown) for driving each device. ). A detection unit 43 of the pupil intensity distribution measuring device 40 is connected to an input side interface (not shown) of the control device 60 so as to receive a detection signal from the detection unit 43. In addition, an input device 61 is connected to the input side interface of the control device 60, and an input signal from the input device 61 is received.

  On the other hand, a display device 62 such as a monitor is connected to an output side interface (not shown) of the control device 60. And the display apparatus 62 displays the pupil intensity distribution for every point of the illumination area ER1 derived | led-out based on the detection signal received from the detection part 43 of the pupil intensity distribution measuring apparatus 40. FIG. Further, a displacement mechanism 58 for individually displacing the light shielding members 55 and 56 of the light shielding unit 47 is connected to an output side interface (not shown) of the control device 60. The control device 60 individually controls the positions of the light shielding members 55 and 56 in the optical path based on the input signal from the input device 61 by the corresponding drive sources 59.

  Next, regarding the operation of the exposure apparatus 11 configured as described above, in particular, the light intensity distribution in the angular direction of the exposure light EL incident on the points P1b and P2b along the Y-axis direction in the still exposure region ER2 is shown. The effect | action at the time of adjusting is demonstrated below.

  Now, in the light shielding unit 47 of this embodiment, as shown in FIG. 10, the exposure light emitted from the surface light sources 51a to 51d and 52a to 52d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. Of the EL, the exposure light EL emitted from the first surface light sources 51 a and 52 a and the second surface light sources 51 b and 52 b is hardly shielded by the light shielding members 55 and 56 constituting the light shielding unit 47. On the other hand, among the pupil intensity distributions 51 and 52 formed on the predetermined surface 39, the exposure light EL emitted from the third surface light sources 51c and 52c and the fourth surface light sources 51d and 52d constitutes a light shielding unit 47. The light shielding members 55 and 56 are partially shielded from light.

  Here, in the light shielding unit 47 of this embodiment, the displacement mechanism 58 translates the first light shielding member 55 in the −Y direction by the distance d from the state shown in FIG. 7 and moves the second light shielding member 56 in the + Y direction. Is translated by a distance d (see FIG. 11). That is, it is assumed that the first light-shielding member 55 and the second light-shielding member 56 are displaced by relative movement so as to pass each other in the Y-axis direction from the facing state illustrated in FIG. In this case, the thickness Zb in the Z-axis direction of the light-shielding unit 47 in a state where both the light-shielding members 55 and 56 are displaced from the facing state is an expression with respect to the coordinate Y in the Y-axis direction with the optical axis AX as the Z-coordinate axis. It is represented by 4.

[Formula 4]
Zb = {a (Y + d) ³ + b (Y + d) + c} + {− a (Y−d) ³ −b (Y−d) + c}
= 6adY ² + 2ad ³ + 2bd + 2c
Therefore, the thickness Zb of the light shielding unit 47 in the displaced state in the Z-axis direction changes depending on the position in the Y-axis direction and the amount of displacement of each of the light shielding members 55 and 56 in the Y-axis direction. Specifically, as shown in FIG. 12, the thickness Zb becomes the largest in the vicinity of the optical axis AX in the Y-axis direction, and gradually decreases as the distance from the optical axis AX along the Y-axis direction increases. It has a convex curved surface-like correlation. Therefore, depending on the position in the Y-axis direction of the point where the exposure light EL emitted from the surface light sources 51a to 51d and 52a to 52d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39 intersects the light shielding unit 47. The thickness Zb of the light shielding unit 47 in the Z-axis direction changes. That is, the light shielding unit 47 has a dimension that projects in the Z-axis direction so as to shield the exposure light EL emitted from the surface light sources 51 a to 51 d and 52 a to 52 d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. The exposure light EL differs depending on the incident position when it enters the light shielding unit 47. The thickness Zb of the light shielding unit 47 in the Z-axis direction varies with the distance from the optical axis AX in the Y-axis direction as the amount of displacement of each light-shielding member 55, 56 in the Y-axis direction increases. Has a gradually increasing correlation.

  Therefore, as shown in FIGS. 11 and 12, the light shielding unit 47 includes the exposure light EL emitted from the third surface light sources 51 c and 52 c of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. From the dimension protruding in the Z-axis direction with respect to the exposure light EL emitted from the third surface light source 51c of the first pupil intensity distribution 51 (that is, the exposure light EL emitted toward the center point P1a of the illumination region ER1). Also, the exposure light EL emitted from the third surface light source 52c of the second pupil intensity distribution 52 (that is, the exposure light EL emitted toward the peripheral point P2a of the illumination region ER1) projects in the Z-axis direction. The dimension becomes smaller.

  Further, the light shielding unit 47 includes the fourth surface of the first pupil intensity distribution 51 out of the exposure light EL emitted from the fourth surface light sources 51d and 52d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. Projecting in the Z-axis direction with respect to the exposure light EL emitted from the fourth surface light source 52d of the second pupil intensity distribution 52 rather than the dimension projecting in the Z-axis direction with respect to the exposure light EL emitted from the light source 51d. The dimension becomes larger.

  As shown in FIGS. 13A and 13B, the light shielding unit 47 includes the third surface light sources 51c and 52c and the fourth surface light sources 51d and 52d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39, respectively. As the size of the exposure light EL emitted from 52d increases in the Z-axis direction, the light shielding amount for the exposure light EL tends to increase. Therefore, according to the light shielding unit 47 of the present embodiment, the exposure light EL emitted from the predetermined surface 39 toward the center point P1a and the peripheral point P2a in the illumination area ER1 is directed to the light shielding members 55 and 56. By making the incident position different in the Y-axis direction, the light shielding amount for the exposure light EL can be changed, and as a result, the light intensity distribution in the angular direction at each point P1a, P1b in the illumination region ER1 is independent. Adjustment is possible.

  By the way, in the exposure apparatus 11 of the present embodiment, the pupil intensity distribution measuring apparatus 40 measures the light intensity distribution in the angular direction for each point in the still exposure region ER2. Here, the first pupil intensity distribution 51 and the second pupil intensity distribution 52 formed on the predetermined surface 39 by the exposure light EL incident on the center point P1b and the peripheral point P2b of the still exposure region ER2 are measured. When the pupil intensity distribution measuring device 40 detects that the light intensity distributions in the angular direction of the two pupil intensity distributions 51 and 52 are different from each other, the control device 60 outputs the fact to the display device 62. To display. Then, the operator sets various conditions regarding the light shielding unit 47 via the input device 61 based on the display result of the display device 62.

  Specifically, the operator sets the light shielding amount of the light shielding unit 47 for the exposure light EL emitted from the third surface light sources 51c and 52c and the fourth surface light sources 51d and 52d of the pupil intensity distributions 51 and 52, respectively. . Then, the light shielding unit 47 determines an appropriate value of the dimension protruding in the Z-axis direction for each exposure light EL so as to satisfy the set light shielding amount. Subsequently, in order to satisfy the determined suitability value, the operator blocks each light shield based on the coordinate Y in the Y-axis direction of each point C1, C2, D1, D2 where the exposure light EL and the virtual surface 57 intersect. The distance d by which the members 55 and 56 are translated in the Y-axis direction is calculated using Equation 4 above.

  Then, the control device 60 drives each drive source 59 based on the set various conditions, so that in the optical path of the exposure light EL emitted from the first surface light sources 51a and 52a on the predetermined surface 39, The light shielding members 55 and 56 are displaced in the Y axis direction, respectively. When the light shielding members 55 and 56 are respectively displaced, the properties of the pupil intensity distributions 51 and 52 measured by the pupil intensity distribution measuring device 40 change in accordance with the displacement modes of the light shielding members 55 and 56, respectively. To do.

  That is, the operator displaces the light shielding members 55 and 56, respectively, and the light intensity distribution in the angular direction of the exposure light EL incident on the center point P1b in the still exposure region ER2 and the peripheral point P2b in the still exposure region ER2. The amount of light shielding with respect to the exposure light EL emitted from the surface light sources 51a to 51d and 52a to 52d of the pupil intensity distributions 51 and 52 is made independent so as to match the light intensity distribution in the angular direction of the exposure light EL incident on the light. By adjusting the position, the pattern formed on the irradiated surface Wa of the wafer W varies, and in particular, the pattern transfer position shift due to the change in telecentricity depending on the position in the exposure region occurs. Can be suppressed.

Therefore, in this embodiment, the following effects can be obtained.
(1) In the present embodiment, the displacement mechanism 58 is arranged in the optical axis direction of the illumination optical system 13 according to the incident position when the exposure light EL emitted from the light source device 12 enters the light shielding unit 47. The light shielding members 55 and 56 are displaced so that the dimensions are different. Therefore, due to the displacement of the light shielding members 55 and 56, the amount of change in the light shielding amount by which the exposure light EL emitted from the light source device 12 is shielded by the light shielding members 55 and 56 is that of the stationary exposure region ER2 where the exposure light EL is incident. Different for each position. Therefore, the displacement mechanism 58 can independently adjust the pupil intensity distribution for each position of the still exposure region ER2 by displacing the light shielding members 55 and 56 in the optical path.

  (2) In this embodiment, each of the light shielding members 55 and 56 constituting the light shielding unit 47 has thicknesses Z1 and Z2 in the optical axis direction of the illumination optical system 13 with respect to the Y axis perpendicular to the optical axis direction. It is defined by a preset third power series. Therefore, the operator protrudes in the optical axis direction of the illumination optical system 13 with respect to the exposure light EL emitted from the third surface light sources 51c and 52c and the fourth surface light sources 51d and 52d of the pupil intensity distributions 51 and 52, respectively. Based on the coordinates Y in the Y-axis direction of the points C1, C2, D1, and D2 at which the exposure light EL and the virtual surface 57 intersect so that the set appropriate value is satisfied when the appropriate value of the dimension is set. Thus, it is possible to calculate the distance d by which the light shielding members 55 and 56 are translated in the Y-axis direction. Therefore, various conditions of the light shielding unit 47 for the exposure light EL emitted from the surface light sources 51a to 51d and 52a to 52d of the pupil intensity distributions 51 and 52 can be determined quickly and accurately.

  (3) In the present embodiment, the light shielding members 55 and 56 are connected to the light shielding members 55 and 56 from the surface light sources 51a to 51d and 52a to 52d of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39, respectively. The light shielding members 55 and 56 are arranged in the vicinity of the illumination area ER1 on the reticle R so that the light shielding amounts of the light shielding members 55 and 56 with respect to the exposure light EL differ according to the incident position of the exposure light EL when incident on the reticle R. Therefore, the displacement mechanism 58 can independently adjust the pupil intensity distribution for each position of the illumination region ER1 by displacing the light shielding members 55 and 56 in the optical path of the exposure light EL. The pupil intensity distribution at each position of the exposure region ER2 can be adjusted independently.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is different from the first embodiment in that the light shielding unit is disposed in the vicinity of a position optically conjugate with the illumination pupil plane. Therefore, in the following description, parts different from those of the first embodiment will be mainly described, and the same or corresponding components as those of the first embodiment will be denoted by the same reference numerals and redundant description will be omitted. And

  As shown in FIGS. 14 to 16, the light shielding unit 47 of the present embodiment includes a first surface light source 50 a and a second surface light source of the secondary light source 30 between the optical integrator 28 and the first condenser optical system 31. Arranged in parallel along the Y-axis direction, which is the optical axis direction of the illumination optical system 13, so as to be positioned in the optical path of the exposure light EL emitted from 50b. The light shielding members 55 and 56 of the light shielding unit 47 of this embodiment have a shape extending in a direction corresponding to the scanning direction (X-axis direction). Here, the direction corresponding to the scanning direction refers to the relationship between the light shielding members 55 and 56 of the light shielding unit 47 and the illuminated surface when light rays are traced from the illuminated surface toward the light shielding members 55 and 56 of the light shielding unit 47. This is the direction after the scanning direction is rotated and reversed by the optical system in between. Of the exposure light EL emitted from the first surface light source 50a and the second surface light source 50b of the secondary light source 30 on the illumination pupil plane 29, the center in the illumination area ER1 and still exposure area ER2 of the reticle R. Let E1 and F1 be the points where the exposure light EL emitted toward the points P1a and P1b intersects the XZ plane (hereinafter referred to as the virtual plane 63) passing through the approximate center of the light shielding unit 47. Of the exposure light EL emitted from the first surface light source 50a and the second surface light source 50b of the secondary light source 30 on the illumination pupil plane 29, the periphery in the illumination area ER1 and still exposure area ER2 of the reticle R Each point where the exposure light EL emitted toward the points P1b and P2b intersects the virtual surface 63 is defined as E2 and F2. In this case, in the present embodiment, since the light shielding unit 47 is disposed in the vicinity of the illumination pupil plane 29, the points E1 and E2 and the points F1 and F2 are illuminated with respect to the surface light sources 50a and 50b respectively corresponding thereto. The optical system 13 is positioned so as to substantially face each other in the Y-axis direction, which is the optical axis direction.

  Further, as shown in FIG. 17A, in the exposure light EL emitted from the first surface light source 50a and the second surface light source 50b of the secondary light source 30, the inside of the illumination area ER1 of the reticle R and the static exposure area ER2 The exposure light EL emitted toward the center points P1a and P1b, that is, the exposure light EL reaching the center point P1 of the opening 34 of the reticle blind 33 is transmitted by the light shielding members 55 and 56 constituting the light shielding unit 47. Is hardly shaded. On the other hand, as shown in FIG. 17B, out of the exposure light EL emitted from the first surface light source 50a and the second surface light source 50b of the secondary light source 30, the inside of the illumination area ER1 of the reticle R and the stationary exposure area ER2 The exposure light EL emitted toward the peripheral points P1b and P2b is shielded with high efficiency by the respective light shielding members 55 and 56 constituting the light shielding unit 47.

  Here, in the light shielding unit 47 of this embodiment, the displacement mechanism 58 translates the first light shielding member 55 in the + X direction and the second light shielding member 56 in the −X direction from the state shown in FIG. (See FIG. 18). In this case, as shown in FIG. 18, the light shielding unit 47 has the exposure light EL emitted from the first surface light source 50 a of the secondary light source 30 as compared with the state before displacement (that is, the state shown in FIG. 16). On the other hand, the dimension in which the second light shielding member 56 projects in the + Y direction is reduced while the dimension in which the first light shielding member 55 projects in the −Y direction is substantially maintained. As a result, the size of the light shielding unit 47 that projects in the Y-axis direction with respect to the exposure light EL is reduced.

  In this case, as shown in FIG. 19A, the light shielding unit 47 is positioned at the center point P1 of the opening 34 of the reticle blind 33 out of the exposure light EL emitted from the first surface light source 50a of the secondary light source 30. The light shielding amount with respect to the exposure light EL emitted toward the surface hardly changes. On the other hand, as shown in FIG. 19B, the light shielding unit 47 is directed toward the peripheral point P2 of the opening 34 of the reticle blind 33 in the exposure light EL emitted from the first surface light source 50a of the secondary light source 30. As a result, the light shielding amount with respect to the exposure light EL emitted is greatly changed (decreased).

  The light shielding unit 47 has a dimension in which the first light shielding member 55 projects in the −Y direction with respect to the exposure light EL emitted from the second surface light source 50b of the secondary light source 30 as compared to the state before displacement. And the dimension in which the second light shielding member 56 projects in the + Y direction is substantially maintained. As a result, the size of the light shielding unit 47 that projects in the Y-axis direction with respect to the exposure light EL is reduced. As a result, the light shielding unit 47 similarly exposes the exposure light EL emitted from the second surface light source 50b of the secondary light source 30 toward the center point P1 of the opening 34 of the reticle blind 33. While the light shielding amount for the light EL hardly changes, the light shielding amount for the exposure light EL emitted toward the peripheral point P2 of the opening 34 of the reticle blind 33 greatly changes (decreases).

  Therefore, according to the light blocking unit 47 of the present embodiment, the exposure light emitted from the first surface light source 50a and the second surface light source 50b of the secondary light source 30 toward the center point P1a and the peripheral point P2a in the illumination area ER1. When the dimension protruding in the Y-axis direction, which is the optical axis direction of the illumination optical system 13, is changed with respect to the EL, the amount of change in the light shielding amount with respect to the exposure light EL can be made different from each other. The light intensity distribution in the angular direction at each point P1a and P1b in the region ER1 can be adjusted independently.

Therefore, in this embodiment, in addition to the effects (1) and (2) of the first embodiment, the following effects can be obtained.
(4) In the present embodiment, the displacement mechanism 58 has the surface light sources 50a to 50d of the secondary light source 30 formed on the illumination pupil plane 29 so as to change the thickness of the illumination optical system 13 in the optical axis direction. The light shielding members 55 and 56 are displaced in the optical path of the exposure light EL emitted from the light. In this case, each light shielding member 55, 56 is the center of the opening 34 of the reticle blind 33 among the exposure light EL emitted from the surface light sources 50 a to 50 d of the secondary light source 30 formed on the illumination pupil plane 29. The amount of change in the light shielding amount with respect to the exposure light EL emitted substantially parallel to the optical axis AX of the illumination optical system 13 toward the point P1 and the peripheral point P2 of the opening 34 of the reticle blind 33 The amount of change in the light shielding amount for the exposure light EL emitted so as to be inclined with respect to the optical axis AX is different from each other. That is, the displacement mechanism 58 displaces the light shielding members 55 and 56 in the optical path of the exposure light EL emitted from the secondary light source 30 formed on the illumination pupil plane 29, thereby changing the position of the stationary exposure region ER2. The light intensity distribution in the angular direction can be adjusted independently.

In addition, you may change the said embodiment into another embodiment as follows.
In the first embodiment, the light shielding unit 47 is an illumination optical system for the first surface light sources 51a and 52a and the second surface light sources 51b and 52b of the pupil intensity distributions 51 and 52 formed on the predetermined surface 39. You may arrange | position so that it may oppose in 13 optical axis directions.

  In the first embodiment, the light shielding unit 47 may be disposed in the vicinity of a surface optically conjugate with the reticle R. For example, the light shielding unit 47 may be disposed between the reticle blind 33 and the first condenser optical system 31 optically substantially conjugate with the reticle R, or between the reticle blind 33 and the second condenser optical system 35. At this time, at the position in the vicinity of the reticle blind 33, the direction corresponding to the scanning direction (X-axis direction) is the Z-axis direction by the second reflecting mirror 37, so that the light-shielding members 55 and 56 of the light-shielding unit 47 extend. It becomes the Z-axis direction.

  In the second embodiment, the light-shielding unit 47 is in the optical axis direction of the illumination optical system 13 with respect to the third surface light source 50c and the fourth surface light source 50d of the secondary light source 30 formed on the illumination pupil plane 29. May be arranged so as to face each other.

  In each of the above embodiments, the light shielding unit 47 is configured such that the surfaces 55a and 56a of the light shielding members 55 and 56 perpendicular to the optical axis AX of the illumination optical system 13 are perpendicular to the optical axis AX of the illumination optical system 13. In addition, it may be configured to have a curved surface shape represented by a power series of secondary or higher. The surfaces 55a and 56a of the light shielding members 55 and 56 are symmetrical with respect to the optical axis AX in the axial direction perpendicular to the optical axis AX of the illumination optical system 13 in the thickness of the illumination optical system 13 in the optical axis direction. In order to obtain a uniform distribution, it is desirable to form a curved surface represented by an odd power series of the third or higher order with respect to an axis orthogonal to the optical axis AX of the illumination optical system 13.

  In each of the above-described embodiments, the light shielding unit 47 includes the light shielding members 55 and 56, the surface of one of the light shielding members orthogonal to the optical axis AX of the illumination optical system 13 is orthogonal to the optical axis AX of the illumination optical system 13. You may comprise so that it may make the curved surface shape represented by the power series more than secondary with respect to the axis line to do.

  In each of the above embodiments, the light shielding unit 47 is represented by a power series of a second or higher order with respect to an axis that is orthogonal to the optical axis AX of the illumination optical system 13. You may comprise by the single light-shielding member which makes the curved surface shape.

  In each of the above embodiments, the light shielding unit 47 may be configured by a light shielding member configured such that the thickness of the illumination optical system 13 in the optical axis direction changes along an axis intersecting the optical axis. In this case, the light shielding unit 47 may be composed of a single light shielding member, or may be composed of a plurality of light shielding members arranged in parallel along the optical axis direction of the illumination optical system 13. The light shielding unit 47 includes a light shielding member configured such that the thickness of the illumination optical system 13 in the optical axis direction changes along an axis intersecting the optical axis, and a constant along the axis intersecting the optical axis. It is good also as a structure which combined the light shielding member comprised so that it might become. In addition, among the plurality of light shielding members, all the light shielding members may be configured to be relatively movable in a direction intersecting the optical axis direction of the illumination optical system 13, or only a part of the light shielding members of the illumination optical system 13 may be configured. You may comprise so that relative movement is possible in the direction which cross | intersects an optical axis direction.

  In each of the above embodiments, the light shielding unit 47 includes a pair of light shielding members 55 and 56, but may include a plurality of pairs of light shielding members 55 and 56. At this time, a plurality of pairs of light shielding members 55 and 56 may be provided along a direction orthogonal to the direction in which the light shielding members 55 and 56 extend. In the first embodiment, a plurality of sets of light shielding members 55 and 56 extending in a direction orthogonal to the scanning direction (X-axis direction) may be provided and arranged so as to have an interval in the scanning direction. In the second embodiment, the light shielding members 55 and 56 extending in a direction corresponding to a plurality of sets of scanning directions (X-axis directions) are provided, and there is an interval in a direction corresponding to a direction orthogonal to the scanning direction. May be arranged as follows.

  In each of the above embodiments, the diffractive optical element 19 may be a diffractive optical element for polarization illumination (for example, for dipole illumination) other than quadrupole illumination, or a diffractive optical element for annular illumination. It may be a circular diffractive optical element. In addition, as long as the optical element can change the shape of the exposure light EL, another arbitrary optical element such as an axico lens pair may be arranged instead of the diffractive optical element.

  In each of the above embodiments, the correction filter 24 may be disposed at an arbitrary position on the incident side of the optical integrator 28 as long as it is optically conjugate with the incident surface of the optical integrator 28. Further, the correction filter 24 may be disposed in the vicinity of the incident surface of the optical integrator 28.

  In the first embodiment, the light shielding unit 47 is near the position optically conjugate with the irradiated surface Ra of the reticle R (or the irradiated surface Wa of the wafer W) on the emission side of the optical integrator 28. If so, it may be arranged at an arbitrary position.

  In the second embodiment, the light shielding unit 47 may be disposed at any position on the exit side of the optical integrator 28 as long as it is in the vicinity of a position optically conjugate with the exit surface of the optical integrator 28. Good.

  In each of the embodiments described above, the pupil intensity distribution measuring device 40 is positioned at any position as long as it is in the vicinity of a position optically conjugate with the irradiated surface Ra of the reticle R (or the irradiated surface Wa of the wafer W). You may arrange.

  In each of the above embodiments, 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 of the above embodiments, the exposure apparatus 11 may be embodied as a scanning stepper that transfers the pattern of the reticle R to the wafer W in a state where the reticle R and the wafer W are relatively moved, and sequentially moves the wafer W stepwise. Good.

  In each of the above embodiments, the optical integrator 28 may be configured by a single micro fly's eye lens in which unit wavefront division surfaces having a refractive index 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. Further, the optical integrator may be a pair of fly-eye mirrors in which a plurality of mirror surfaces are arranged. Further, the optical integrator may be a rod lens extending along the Y-axis direction.

  In each of the above embodiments, 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 Micro-mirror Device)).

In each of the above embodiments, 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.

  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. 20 is a flowchart showing a manufacturing example of a microdevice (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micromachine, or the like).

  First, in step S101 (design step), function / performance design (for example, circuit design of a semiconductor device) of a micro device is performed, and 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 lithography 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. 21 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.

  When the above-mentioned pretreatment process is completed in each stage of the substrate process, 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.

  DESCRIPTION OF SYMBOLS 11 ... Exposure apparatus, 12 ... Light source apparatus as a light source, 13 ... Illumination optical system, 15 ... Projection optical system, 19 ... Diffractive optical element as an optical element, 28 ... Optical integrator, 47 ... Light shielding unit, 55, 56 ... Light shielding 58: Displacement mechanism, AX: Optical axis, EL: Exposure light as light, Ra: Irradiated surface, W: Wafer as photosensitive substrate.

Claims (16)

In a light-shielding unit that is provided in an illumination optical system that illuminates an irradiated surface with light emitted from a light source via an optical integrator, and adjusts the light intensity distribution in the angular direction of a light beam that reaches the irradiated surface.
A light-shielding element that is disposed closer to the irradiated surface than the optical integrator in the optical path of the light, and is configured such that the dimension in the optical axis direction of the illumination optical system differs depending on the position in the plane that intersects the optical axis. Members,
A light shielding unit, comprising: a displacement mechanism capable of displacing the light shielding member in a direction intersecting the optical axis direction in the optical path of the light. The light shielding unit according to claim 1,
The light-shielding unit is configured to displace the light-shielding member so as to change the dimension of the light-shielding member in the optical axis direction for each position intersecting the optical axis direction. . In the light-shielding unit according to claim 1 or 2,
A plurality of the light shielding members are arranged in the middle of the light path of the light. The light shielding unit according to claim 3,
The respective light shielding members are arranged adjacent to each other along the optical axis direction. In the light-shielding unit according to claim 3 or 4,
The light shielding unit, wherein the displacement mechanism is configured to be able to relatively displace the light shielding members in a direction intersecting the optical axis direction. The light shielding unit according to claim 5,
The displacement mechanism is configured to be capable of relative displacement of each light shielding member so as to change the total sum of the dimensions of each light shielding member in the optical axis direction for each position in a direction intersecting the optical axis. A shading unit characterized by that. In the light-shielding unit according to any one of claims 1 to 6,
The light-shielding unit, wherein the light-shielding member has a curved surface that intersects the optical axis. The light shielding unit according to claim 7,
The light-shielding unit, wherein the light-shielding unit has a correlation in which the dimension in the optical axis direction is defined by a power series of second or higher order with respect to the distance from the optical axis. The light shielding unit according to claim 8,
The light-shielding unit, wherein the light-shielding member has a correlation in which the dimension in the optical axis direction is defined by an odd-order power series of the third or higher order with respect to a distance from the optical axis. In the light-shielding unit according to any one of claims 1 to 9,
The light shielding unit, wherein the light shielding member is disposed in the vicinity of an exit surface of the optical integrator or in the vicinity of a position optically conjugate with the exit surface. The light shielding unit according to claim 10,
The illumination optical system moves the predetermined pattern projected on the irradiated surface and the photosensitive substrate disposed on the irradiated surface along the scanning direction while moving the predetermined pattern on the photosensitive substrate. Used in combination with an exposure device that exposes,
The light shielding unit, wherein the light shielding member has a shape extending in a direction corresponding to the scanning direction. In the light-shielding unit according to any one of claims 1 to 9,
The light shielding unit, wherein the light shielding member is disposed in the vicinity of the irradiated surface or in the vicinity of a position optically conjugate with the irradiated surface. The light shielding unit according to claim 12,
The illumination optical system moves the predetermined pattern projected on the irradiated surface and the photosensitive substrate disposed on the irradiated surface along the scanning direction while moving the predetermined pattern on the photosensitive substrate. Used in combination with an exposure device that exposes,
The light shielding unit, wherein the light shielding member has a shape extending in a direction corresponding to a direction orthogonal to the scanning direction. An illumination optical system that illuminates an illuminated surface based on light emitted from a light source,
An optical element disposed in the optical path of the light;
An illumination optical system comprising: the light shielding unit according to any one of claims 1 to 13. An illumination optical system according to claim 14,
An exposure apparatus comprising: a projection optical system capable of projecting a predetermined pattern image onto the irradiated surface. In the device manufacturing method,
Exposing a predetermined pattern to a photosensitive substrate using the exposure apparatus according to claim 15;
Developing the exposed substrate and forming a mask layer having a shape corresponding to the pattern on the surface of the photosensitive substrate;
And a step of processing the surface of the photosensitive substrate through the mask layer.

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