JP5843905B2 - Illumination optical system, exposure apparatus, and device manufacturing method - Google Patents

Description

  The present invention relates to an illumination optical system, an exposure apparatus, and a device manufacturing method.

  In the lithography process among the manufacturing processes of semiconductor devices and liquid crystal display devices, the mask (reticle) is illuminated by an illumination optical system, and the pattern of the mask is formed on the substrate on which the photosensitive resist layer is formed via the projection optical system. An exposure apparatus that projects an image is used. In an exposure apparatus, an effective light source distribution (illumination condition) is optimized in accordance with a mask pattern in order to ensure a depth of focus while obtaining high resolution. The effective light source distribution is a light intensity distribution on the pupil plane of the illumination optical system, and is also an angular distribution of light incident on a mask (illuminated surface) by the illumination optical system.

  Patent Document 1 describes that a conical prism or a pyramid prism is used to change the cross-sectional shape of a light beam to an annular shape, thereby forming an annular effective light source distribution (annular illumination). Patent Document 2 describes forming annular illumination or quadrupole illumination using a pair of conical prisms and a pair of pyramid prisms.

  In Patent Document 3, light emitted from a conical prism is incident on an illumination light uniformizing optical system composed of a columnar reflecting member and a cylindrical reflecting member, and a ring having a uniform light intensity distribution is disclosed. It is described that band illumination is formed.

JP 2002-343715 A JP 11-271619 A International Publication No. 99 / 2,5009 Pamphlet

  FIG. 13 shows a schematic diagram of an exposure apparatus having an illumination optical system using a prism as described in Patent Documents 1 and 2. The exposure apparatus has an illumination optical system IL and a projection optical system PO. The light source 1 is a light source that emits a rotationally symmetric light distribution. The light from the light source 1 passes through the optical system 2, the conical prism 3, and the optical system 4 and enters the mask M. The diffracted light emitted from the mask M enters the projection optical system PO and forms an image on the substrate P through the aperture stop (NA stop) 5. The conical prism 3 is disposed on the Fourier transform plane with respect to the mask M. The effective light source distribution is changed from a circular shape to an annular shape. This is expressed using solid and dotted lines. The dotted line represents how light passes when the conical prism 3 is not present, and the solid line represents how light passes when the conical prism 3 is present. It can be seen that the light beam spreads by the action of the conical prism 3 and enters the mask M at an incident angle larger than the incident angle of the light indicated by the dotted line. As a result, a part of the light is blocked by the aperture stop 5 of the projection optical system PO, and the exposure amount of the substrate P is reduced. In other words, this means that a part of the light from the illumination optical system IL is not used, and it can be said that the light use efficiency is lowered.

  As described above, since the light beam spreads in the conventional conical prism 3, a part of light is blocked by the light shielding member after the conical prism 3, or a part of light is applied to the optical element after the conical prism 3. The light utilization efficiency was reduced due to the inability to enter.

  Further, when an illumination light uniformizing optical system as described in Patent Document 3 is used, the angular distribution of light emitted from the optical system is wider than the angular distribution of light incident on the optical system. Have. As a result, part of the light cannot enter the subsequent optical element, and the light use efficiency decreases.

  Therefore, an object of the present invention is to provide an illumination optical system that can suppress a decrease in light utilization efficiency when exposing a substrate using light from a prism that changes the cross-sectional shape of a light beam.

  An illumination optical system according to one aspect of the present invention that solves the above-described problem is an illumination optical system that includes a prism that changes a cross-sectional shape of a light beam and illuminates a surface to be illuminated. A light exit surface and an outer surface extending from the light entrance surface side to the light exit surface side, the light entrance surface has a concave cone surface, and the light exit surface has a convex cone surface, The outer surface includes a reflecting surface that reflects light incident on the outer surface from the light incident surface.

  ADVANTAGE OF THE INVENTION According to this invention, the fall of the light utilization efficiency at the time of exposing a board | substrate using the light from the prism which changes the cross-sectional shape of a light beam can be suppressed.

1 is a schematic diagram of an illumination optical system in Embodiment 1. FIG. It is the schematic of a fly eye optical system. It is the schematic of a field stop. FIG. 3 is a diagram illustrating a prism in the first embodiment. It is a figure for demonstrating the effect by the prism in Example 1. FIG. 6 is a diagram illustrating a prism in Embodiment 2. FIG. FIG. 6 is a diagram illustrating a prism in Example 3. FIG. 6 is a diagram illustrating a prism in Example 4. It is the schematic which shows the exposure apparatus in Embodiment 2. FIG. It is a figure which shows the optical rod of a hexagonal column. FIG. 6 is a diagram illustrating a prism according to a second embodiment. It is the schematic of a (sigma) aperture changer. It is a figure for demonstrating the problem of the prior art prism. FIG. 10 is a diagram illustrating a prism in Example 5.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(Embodiment 1)
The configuration of the illumination optical system according to the first embodiment of the present invention will be described with reference to FIGS.

  The illumination optical system of the present embodiment is an apparatus that is used in, for example, an exposure apparatus and guides light from a light source to a mask (reticle) on which a pattern that is an irradiation target is formed. The exposure apparatus forms an image of diffracted light from a mask pattern using a projection optical system, and projects an image of the mask pattern onto a substrate (wafer, glass plate, etc.) to expose the substrate.

  FIG. 1 is a schematic diagram illustrating a configuration of an illumination optical system according to the present embodiment. The light source unit 120 includes a light source 101 and an elliptical mirror 102. The illumination optical system includes a prism (optical system) 104, a first optical system 105, a deflection mirror 107, a second optical system 140, a fly-eye optical system 109, a σ stop 110, a third optical system 150, a field stop 111, and a fourth. An optical system 160 is included. The illumination optical system illuminates the mask M on the surface to be illuminated.

  The light source 101 is a high pressure mercury lamp. In addition, a xenon lamp, an excimer laser, or the like can be used as the light source 101. The elliptical mirror 102 is a condensing optical system for condensing the light emitted from the light source 101, has a shape using a part of the elliptical shape, and places the light source 101 at one of the two focal positions of the ellipse. It is arranged.

  The light emitted from the light source 101 and reflected by the elliptical mirror 102 is condensed on the prism 104 disposed in the vicinity of the other focal position of the ellipse. The prism 104 transmits incident light, changes the cross-sectional shape of the incident light beam, and emits light. The light passing through the prism 104 is guided to the deflection mirror 107 by the first optical system 105 and reflected by the deflection mirror 107.

  In the present embodiment, there are two light source sections 120, and the deflection mirror 107 is disposed for each light source section. Although the arrangement of the deflecting mirrors differs depending on the number of light sources, the number of light sources may be one or three or more.

  The first optical system 105 is configured such that the surface 108 is substantially at a Fourier transform position with respect to the exit surface of the prism 104. Therefore, the annular light intensity distribution on the exit surface of the prism 104 becomes the angular distribution of the light incident on the surface 108. In FIG. 1, light rays of an angular distribution (light intensity distribution on the surface 108) of light emitted from the exit surface of the prism 104 are drawn. Light from the surface 108 is guided to the fly-eye optical system 109 by the second optical system 140. The second optical system 140 is configured such that the incident surface of the fly-eye optical system 109 is substantially at the Fourier transform position with respect to the surface 108.

  FIG. 2 is a diagram illustrating the fly-eye optical system 109. As shown in FIG. 2, the fly-eye optical system 109 includes two lens groups 131 and 132 in which a number of plano-convex lenses are bonded together in a planar shape. The planes of curvature are arranged facing each other so that there is a pair of plano-convex lenses at the focal position of each plano-convex lens constituting the lens groups 131 and 132. By using such a fly-eye optical system 109, a secondary light source distribution (effective light source distribution) is formed on the exit surface side of the fly-eye optical system 109.

  The light beam emitted from the exit surface of the fly-eye optical system 109 is guided to the field stop 111 by the third optical system 150 via the σ stop 110. The σ stop 110 adjusts the shape of the effective light source distribution according to the aperture shape. The third optical system 150 is configured such that the position of the field stop 111 is substantially a Fourier transform surface with respect to the exit surface 110 of the fly-eye optical system 109. Since the secondary light source distribution is formed on the exit surface side of the fly-eye optical system 109, the light intensity distribution is uniform on the field stop 111.

  FIG. 3 shows a configuration diagram of the field stop 111. In the field stop 111, an arc-shaped slit (opening) 23 is formed, and light other than the slit 23 is shielded. The arc-shaped light flux that has passed through the slit 23 is uniformly illuminated on the mask M by the third optical system 160. Although the slit of the field stop 111 has an arc shape, other shapes such as a rectangular shape may be used.

  Next, an embodiment of the prism 104 will be described.

(Example 1)
A prism 104A in this embodiment is shown in FIG. FIG. 4A shows a perspective view of the prism 104A. FIG. 4B shows a cross-sectional view taken along a plane including the optical axis of the prism 104A and a side view seen from the right side. The prism 104A has a cylindrical optical rod as a base, a part near the center of one side is formed in a concave conical surface like 104A1, and a part near the center of the other side is convex like 104A3. It is formed on the conical surface. An axis connecting the vertex of the concave conical surface 104A1 and the vertex of the convex conical surface 104A3 is defined as an optical axis.

  In the illumination optical system, the prism 104A is arranged such that its concave conical surface 104A1 is on the light source side and the convex conical surface 104A2 is on the opposite side of the light source side. The prism 104A includes a light incident surface, a light output surface, and an outer surface formed by one optical element. The light incident surface of the prism 104A has a concave conical surface 104A1 and an annular flat surface 104A2 (first surface) formed around the concave conical surface 104A1. That is, on the light incident surface, the first surface 104A2 is outside as viewed from the central axis of the concave conical surface 104A1. The concave conical surface 104A1 is a rotationally symmetric surface with respect to the central axis (optical axis) passing through the apex. The light exit surface has a convex conical surface 104A3 and an annular flat surface 104A4 (second surface) formed around the convex conical surface 104A3. That is, the second surface 104A4 is on the outer side when viewed from the central axis of the convex conical surface 104A3 on the light emitting surface. The convex conical surface 104A3 is a rotationally symmetric surface with respect to the central axis (optical axis) passing through the apex. Further, the light emitting surface has a cylindrical inner side surface 104A5 between the convex conical surface 104A3 and the flat surface 104A4. The inner side surface 104A5 is formed so as to connect the outermost periphery viewed from the central axis of the convex conical surface 104A3 and the inner periphery of the second surface 104A4, and is a side surface of a cylinder disposed so as to surround the convex conical surface 104A3. . Further, the prism 104A has an outer surface 104A6 extending from the light incident surface side to the light emitting surface side. The outer side surface 104A6 is formed to connect the outer periphery of the first surface 104A2 of the light incident surface and the outer periphery of the second surface 104A4 of the light emitting surface.

  FIG. 4C shows how each light beam from the light source passes through the prism 104A. The light ray 1 enters the first surface 104A2, is totally reflected by the outer surface 104A6, and then exits from the second surface 104A4. The light ray 2 enters the concave conical surface 104A1 and exits from the convex conical surface 104A3. The light ray 3 enters the concave conical surface 104A1, exits from the convex conical surface 104A3, and is reflected by the inner side surface 104A5.

  Thus, the light incident on the outer surface 104A6 from the light incident surface is configured to be totally reflected by the outer surface 104A6. The reflective surface may be configured by forming a reflective film on the outer surface 104A6. That is, the outer surface 104A6 has a reflecting surface that reflects light incident on the outer surface from the light incident surface. For this reason, it is possible to prevent the light incident from the light incident surface from spreading outward and to be emitted, and the outer diameter of the incident-side light beam and the outer diameter of the light-emitting beam can be made the same. Accordingly, it is possible to reduce the amount of light that is blocked by the diaphragm on the pupil plane of the projection optical system, or to reduce the amount of light that is kicked without being incident on the subsequent optical element. That is, it is possible to suppress a decrease in light use efficiency when the substrate is exposed using light from the prism 104A. Further, if the conical surfaces of the concave conical surface 104A1 and the convex conical surface 104A3 are the same shape and the first surface and the second surface are parallel to each other, the angle of incident light and the angle of outgoing light with respect to the optical axis are the same and preserved. Is done. For example, light incident parallel to the optical axis is emitted in parallel.

  Further, the inner side surface 104A5 is a reflecting surface composed of a reflecting film that reflects light emitted from the convex conical surface 104A3. The reflective film may not be formed on the inner side surface 104A5, but by forming the reflective film, the light axis emitted from the convex side surface 104A3 is reflected by the inner side surface 104A5 and emitted from the prism 104A. The spread of light can be suppressed while the angle with respect to is preserved.

  If a reflection film is formed on the inner side surface 104A5, the light emitted from the prism 104A is less spread than the light incident on the prism 104A. For this reason, in the optical system subsequent to the prism 104A, the amount of light to be shielded is reduced, and a decrease in light use efficiency can be further suppressed. The dimensions of the prism 104A are ro = 17.5, ri = 17.5, t = 35, d = 52.5 (unit is mm), and the glass material is synthetic quartz.

  For example, it is assumed that light having an intensity distribution as shown in FIG. 5A is incident on the incident surface of the prism 104A from the light source side. However, it is assumed that the optical axis is a direction that penetrates the coordinate origin of FIG. At this time, the light intensity distribution on the exit surface of the prism 104A has an annular shape as shown in FIG.

  If the prism 104A is not used, in order to create an annular light intensity distribution, the intensity distribution shown in FIG. 5A needs to be cut into an annular shape using an aperture stop or the like. FIG. 5C shows the light intensity distribution when the intensity distribution of FIG. 5A is cut into an annular shape with an aperture stop.

  FIG. 5D shows an energy distribution of a cross section taken along a broken line in FIGS. 5B and 5C. The solid line in FIG. 5D is the case of FIG. 5B, and the dotted line in FIG. 5D is the case of FIG. Comparing these, in the case of FIG. 5B (when the prism 104A is used), the accumulated light energy is about 60% higher than in the case of FIG. 5C.

(Example 2)
Next, a second embodiment of the prism 104 is shown. The prism 104 of the present embodiment is an optical element group 104B configured by dividing the prism 104A used in the first embodiment.

  FIG. 6 is a cross-sectional view including the optical axis of the optical element group 104B. The optical element group 104B includes two optical elements 104B1 and 104B2. As an example, synthetic quartz is used for the glass material. The optical element 104B1 (first optical element) has a shape obtained by hollowing out the vicinity of the center of a cylindrical optical rod. The optical element 104B1 is a hollow cylindrical rod having a flat surface 104A2 (first surface) and a flat surface 104A4 (second surface) of the prism 104A as a bottom surface and a top surface and an outer surface 104A6. The optical element 104B2 (second optical element) is a conical prism having a concave conical surface on one side and a convex conical surface on the other side. The concave conical surface of the optical element 104B2 is the concave conical surface 104A1, and the convex conical surface of the optical element 104B2 is the same as the convex conical surface 104A3. The optical element 104B2 is disposed in the hollow portion of the optical element 104B1.

  The optical element group 104B can be arranged in the same manner as the prism 104A with respect to the illumination optical system 100, and an equivalent effect can be expected.

  When manufacturing the prism 104A, it is difficult to process the concave conical surface and the concave conical surface. Further, in the prism 104A, it is desirable to put a permeable film on the flat surface portion and the conical surface portion, but it is difficult to wear a uniform permeable film. On the other hand, in the optical element group 104B, the optical element 104B1 and the optical element 104B2 are manufactured and combined independently of each other, and thus the above problem is eliminated. Therefore, the optical element group 104B is easier to manufacture than the prism 104A, and the manufacturing yield is improved.

  The optical element group 104B is preferably configured by bonding the optical element 104B1 and the optical element 104B2. At this time, a dielectric film having a refractive index lower than that of synthetic quartz may be formed on the joint surface between the optical element 104B1 and the optical element 104B2 with a thickness approximately equal to the wavelength of light to be used. In this case, the light is totally reflected at the boundary between the optical element 104B1 and the optical element 104B2, and the energy of the light is maintained.

(Example 3)
Next, a third embodiment of the prism 104 will be described. The prism 104 of this embodiment is an optical element group 104C configured by dividing the prism 104A used in the first embodiment. The division method is different from that of the optical element group 104B.

  FIG. 7 is a cross-sectional view including the optical axis of the optical element group 104C. The optical element group 104C includes two optical elements 104C1 and 104C2. As an example, synthetic quartz is used for the glass material. The optical element 104C1 (fourth optical element) has a shape in which the vicinity of the center of a cylindrical optical rod is hollowed out, has a flat surface 104A4 (second surface) of the prism 104A on the light emission surface side, and is part of the outer surface 104A6. A hollow cylindrical rod having The optical element 104C2 (third optical element) is a prism having a concave conical surface 104A1, a flat surface 104A2 (first surface), a convex conical surface 104A3, and a part of the outer surface 104A6 of the prism 104A. The optical element 104C1 has the convex conical surface 104A3 of the optical element 104C2 disposed in its own hollow.

  The optical element group 104C can be arranged in the same manner as the prism 104A with respect to the illumination optical system 100, and an equivalent effect can be expected. Similar to the second embodiment, it can be said that the optical element group 104C is also easier to manufacture than the prism 104A.

  Similarly to the inner side surface 104A5 of the prism 104A, when a reflective film is applied to the inner side surface of the optical element 104C1, the optical element group 104C is configured by a plurality of optical elements, so that vapor deposition is easier than the prism 104A. Further, it is easier to deposit the reflective film on the entire inner surface of the optical element 104C1 than to deposit it on a part of the inner surface of the optical element 104B1.

Example 4
Next, a fourth embodiment of the prism 104 will be described. The prism 104 of the present embodiment is an optical element group 104D configured by dividing the prism 104A used in the first embodiment.

  FIG. 8 shows a cross-sectional view through the optical axis of the optical element group 104D. The optical element group 104D includes three optical elements 104C1, 104B2, and 104D1.

  The optical element 104C1 is the optical element shown in the third embodiment. The optical element 104B2 is the optical element shown in the second embodiment. The optical element 104D1 is a hollow cylindrical rod having a flat surface 104A2 (first surface) of the prism 104A and a part of the outer surface 104A6.

  As an example of the other optical element group of the prism 104, those obtained by dividing the optical element 104C1 by various division methods such as those obtained by dividing the optical element 104C1 into two or four in a cross section passing through the central axis of a cylinder can be applied.

  By configuring the prism 104 using such a prism or optical element group, it is possible to suppress a decrease in light use efficiency and prevent a decrease in illuminance on the irradiated surface even in modified illumination such as annular illumination. be able to.

  In addition, although the conical surface was used for the prism 104, a pyramid surface may be sufficient, and the concave cone surface and convex cone surface of a circle | round | yen or a corner should just be comprised. Although the side surface of the prism 104 is a cylinder, it may be a prism.

  For example, in order to increase the amount of light taken in by the projection optical system, it is conceivable to increase the aperture diameter of the aperture stop on the pupil plane. However, when the aperture diameter of the aperture stop 5 is enlarged, the numerical aperture (NA) of the projection optical system is enlarged and the depth of focus is reduced, so that the process margin of the exposure apparatus is lost.

(Example 5)
Next, a fifth embodiment of the prism 104 will be described. FIG. 14 shows a cross-sectional view taken along a plane including the optical axis of the prism 104E and a side view seen from the right side. The prism 104E includes an optical element 104E1 and an optical element E2. The optical element 104E1 has a circular-concave cone surface 104E11, a circular-convex cone surface 104E12, and an outer surface 104E13 that connects the outer periphery of the circular-concave cone surface 104E11 and the outer periphery of the circular-convex cone surface 104E12. The optical element 104E2 is a hollow columnar member and has an inner side surface 104E22. A reflective film is attached to the inner side surface 104E22. The inner side surface 104E22 is a side surface of a cylinder arranged so as to surround the circular convex conical surface 104E12. The light ray 1E enters the circular concave conical surface 104E11, travels through the optical element 104E1, and exits from the circular convex conical surface 104E12. The light ray 2E enters the circular concave cone surface 104E11, travels through the optical element 104E1, exits from the circular convex cone surface 104E12, is further reflected by the inner side surface 104E22, and exits from the prism 104E. That is, the light beam 2E incident on the circular concave cone surface 104E11 with an angle in the outer direction with respect to the optical axis is emitted from the circular convex cone surface 104E12, then reflected by the inner side surface 104E22 and emitted toward the inner direction. The light ray 3E enters the circular concave cone surface 104E11, is totally reflected by the outer surface 104E13 while traveling through the optical element 104E1, and is emitted from the circular convex cone surface 104E12. Thus, the outer surface 104E13 has a function of a reflecting surface that totally reflects light. The light ray 3E is refracted in the outward direction by the circular-concave conical surface 104E11, and is totally reflected by the outer surface 104E13, thereby traveling in the inward direction. Therefore, by having the outer surface 104E13 and the inner surface 104E22, the light emitted from the prism 104E can be prevented from spreading. If the conical surfaces of the circular concave conical surface 104E11 and the circular convex conical surface 104E12 have the same shape and the outer surface 104E13 and the inner surface 104E22 are parallel to the optical axis, the emitted light is emitted at an angle equivalent to the incident light.

(Embodiment 2)
The configuration of the projection exposure apparatus according to the second embodiment of the present invention will be described with reference to FIG. The same reference numerals used in the drawings are common and a part of the description is omitted.

  The illumination optical system includes the prism 104A of the first embodiment, the hexagonal optical rod 114 shown in FIG. 10, and the prism 106 shown in FIG. Further, a prism changer 112 is provided which places these optical members in and out of the optical path and selectively arranges one optical member in the optical path.

  As shown in FIG. 11A, the prism 106 has an outer convex conical surface 1061 and an inner convex conical surface 1062 on the light incident surface. Further, the light exit surface has a concave conical surface 1063, and the vicinity of the center is hollow. FIG. 11B shows light rays that pass through the prism 106. When the convex conical surface is disposed on the entrance surface and the concave conical surface is disposed on the exit surface side, the light beam 4 enters the convex conical surface 1061 and approaches the optical axis O. However, when the region through which the light beam passes, such as the light beam 5 and the light beam 6, has no refracting surface, the way the light beam travels is not affected as shown in the figure. Thereby, when the prism 106 is used, the diameter of the emitted light beam can be suppressed smaller than the incident light beam.

  In order to reduce the spread of the light intensity distribution (effective light source distribution) formed on the pupil plane of the illumination optical system, it is necessary to cut the outer periphery of the effective light source distribution with a σ stop, etc. Will fall. However, by using the prism 106, the effective light source shape can be reduced, and a decrease in light utilization efficiency can be suppressed.

  Further, the illumination optical system constitutes a σ stop changer 113 in which a plurality of σ stops having different aperture shapes can be selectively arranged near the exit surface of the fly-eye optical system 109.

  FIG. 12 is a schematic view of the σ aperture changer 113. For example, when the prism changer 112 is driven and the optical rod 114 is disposed in the optical path, the σ stop changer 113 is driven so that the σ stop 113A is disposed near the exit surface of the fly-eye optical system 109. Further, when the prism changer 112 is driven to place the prism 104 in the optical path, the σ stop changer 113 is driven so that the σ stop 113B is arranged near the exit surface of the fly-eye optical system 109. Further, when the prism changer 112 is driven and the prism 106 is disposed in the optical path, the σ stop changer 113 is driven so that the σ stop 113C is disposed near the exit surface of the fly-eye optical system 109.

  The projection exposure apparatus of this embodiment can form a plurality of types of effective light source distributions (illumination conditions) using the prism changer 112 and the σ stop changer 113, and selects the effective light source distribution according to the pattern of the mask M. Then, the mask M is illuminated. The projection exposure apparatus projects the pattern of the mask M onto the substrate P via the projection optical system PO to expose the substrate P. According to the projection exposure apparatus of this embodiment, according to the pattern of the mask M, an effective light source distribution with high pattern resolution performance can be selected to illuminate the mask M and expose the substrate, thereby improving productivity. Can be made.

  The projection exposure apparatus of this embodiment includes a measuring instrument JS that measures the angular distribution (effective light source distribution) of light incident on the substrate P. The measuring instrument JS is disposed in a substrate stage PS that holds and moves the substrate. The measuring instrument JS has a pinhole plate in which a pinhole having a diameter of 1 mm or less is formed, and a CCD camera at a position about 100 mm away from the pinhole. When measuring the angular distribution of the light incident on the substrate P, the measuring device JS is moved into the exposure area so that the pinhole is positioned on the image plane, and the light distribution transmitted through the pinhole is imaged by the CCD camera. An angular distribution of light incident on the substrate P using image data obtained by the CCD camera can be obtained. Then, the position and orientation of the prism 104 are adjusted so that the angular distribution of the light incident on the substrate P using the obtained angular distribution becomes a desired angular distribution. The measuring instrument JS can also be used for telecentric adjustment of the projection optical system.

(Embodiment 3)
Next, a method for manufacturing a device (semiconductor IC element, liquid crystal display element, etc.) using the above-described exposure apparatus will be described. The device uses the above-described exposure apparatus to expose a substrate (wafer, glass substrate, etc.) coated with a photosensitive agent, to develop the substrate (photosensitive agent), and other well-known steps. It is manufactured by going through. Other known processes include etching, resist stripping, dicing, bonding, packaging, and the like. According to this device manufacturing method, it is possible to manufacture a higher quality device than before.

Claims (13)

An illumination optical system that changes the cross-sectional shape of the light beam , includes an optical system including a prism , and illuminates the illuminated surface,
The prisms may have a light incident surface, a light exit surface, and an outer surface extending to the light emitting surface side from the light incident surface side,
The light incident surface has a concave conical surface;
The light exit surface has a convex cone surface;
Said outer side surface have a reflection surface for reflecting light incident on said outer surface from the light incident surface,
The light incident surface has a first surface located outside the concave cone surface when viewed from a central axis passing through the apex of the concave cone surface;
The light exit surface, the illumination optical system characterized in that it have a second surface which is viewed from the central axis through the apex of the convex conical surface on the outside of the convex conical surface. The illumination optical system according to claim 1 , wherein the illumination optical system guides light so that light enters the concave conical surface and the first surface of the light incident surface. The prisms are,
A hollow columnar optical element having the first surface and the second surface as a bottom surface and a top surface and having the outer surface;
In the hollow portion of the front Symbol light optical element, an illumination optical system according to claim 1 or 2, characterized in that it is an optical element, in configuration having a convex conical surface and the凹錐surface. The prisms are,
An optical element having the concave conical surface, the first surface, the convex conical surface, and the outer surface;
The illumination optics according to claim 1 or 2 , wherein the convex cone surface is arranged in a hollow, and is constituted by the second surface and a hollow columnar optical element having the outer surface. system. An illumination optical system that changes the cross-sectional shape of the light beam, includes an optical system including a prism, and illuminates the illuminated surface,
The prism has a light incident surface, a light emitting surface, and an outer surface extending from the light incident surface side to the light emitting surface side,
The light incident surface has a concave conical surface;
The light exit surface has a convex cone surface;
The outer surface has a reflecting surface that reflects light incident on the outer surface from the light incident surface;
Said optical system including a prism, irradiation Meiko science system you characterized in that it has a reflecting surface for reflecting light emitted from the convex conical surface. The illumination optical system according to claim 5 , wherein a reflection surface that reflects light emitted from the convex cone surface is formed on a cylindrical side surface disposed so as to surround the convex cone surface. An illumination optical system that changes the cross-sectional shape of the light beam, includes an optical system including a prism, and illuminates the illuminated surface,
The prism has a light incident surface, a light emitting surface, and an outer surface extending from the light incident surface side to the light emitting surface side,
The light incident surface has a concave conical surface;
The light exit surface has a convex cone surface;
The outer surface has a reflecting surface that reflects light incident on the outer surface from the light incident surface;
The optical system including the prism is
An optical element having the concave conical surface, the convex conical surface, and the outer surface;
Reflecting surface for reflecting light emitted from the convex conical surface on the inner surface is formed, hollow columnar irradiation Meiko science system you characterized in that it is composed of an optical element. The illumination optical system according to claim 1, wherein the reflection surface totally reflects light incident from the light incident surface. The illumination optical system according to claim 1, wherein the reflection surface is a surface on which a reflection film is formed. The optical system including the prism is configured by joining a plurality of optical elements,
The illumination optical system according to any one of claims 1 to 9, wherein a film having a refractive index lower than that of the plurality of optical elements is formed on a bonding surface of the plurality of optical elements. The outer diameter of the light beam emitted from the optical system including the prism according to any one of claims 1 to 10, characterized in that the same as the outer diameter of the light beam incident on the optical system including the prism Illumination optical system. An illumination optical system according to any one of claims 1 to 11 for illuminating a mask, an exposure apparatus having a projection optical system for projecting an image of a pattern of the mask on the substrate. 13. A device manufacturing method comprising: exposing a substrate using the exposure apparatus according to claim 12 ; and developing the exposed substrate.