HK1193475B - Illumination optical apparatus, exposure apparatus, illumination method, exposure method, and device manufacturing method - Google Patents

Description

Illumination optical apparatus, exposure apparatus, illumination method, exposure method, and device manufacturing method

The present application is a divisional application of an invention patent application having an application number of 200880100940.0, application date of 2008, 10 and 23, and an invention title of "optical unit, illumination optical apparatus, exposure apparatus, and device manufacturing method".

Technical Field

The invention relates to an optical unit, an illumination optical apparatus, an exposure apparatus, and a device manufacturing method. More particularly, the present invention relates to an illumination optical apparatus suitable for an exposure apparatus for manufacturing devices such as semiconductor devices, imaging devices, liquid crystal display devices, and thin film magnetic heads by photolithography.

Background

In a typical exposure apparatus of this type, a light beam emitted from a light source travels through a fly eye lens as an optical integrator to form a secondary light source (in general, a predetermined light intensity distribution on an illumination pupil) as a substantial surface illuminant composed of a large number of light sources. The light intensity distribution on the illumination pupil will be referred to as "illumination pupil luminance distribution" hereinafter. The illumination pupil is defined as a position of a Fourier transform surface that makes the illumination target surface into the illumination pupil by the action of an optical system between the illumination pupil and the illumination target surface (a mask or a wafer in the case of an exposure apparatus).

The beams from the secondary light sources are condensed by condenser lenses to overlappingly illuminate the mask on which the predetermined pattern is formed. Light passing through the mask travels through projection optics to be focused on the wafer, thereby projecting (or transferring) the mask pattern onto the wafer to effect its exposure. Since the pattern formed on the mask is a highly integrated pattern, it is necessary to obtain a uniform illuminance distribution on the wafer in order to accurately transfer this fine pattern onto the wafer.

There is a conventionally proposed illumination optical apparatus capable of continuously changing the illumination pupil luminance distribution (and thus the illumination condition) without using a zoom optical system (refer to japanese patent laid-open application No. 2002-353105). The illumination optical apparatus disclosed in laid-open application No. 2002-353105 uses a movable multi (multi) mirror composed of a large number of micro-mirror elements which are arranged in an array form and whose inclination angles and inclination directions are individually drive-controlled, and is configured such that an incident beam is divided into small-cell beams corresponding to the reflective surfaces of the mirror elements, which are folded by the multi-mirror to convert the cross section of the incident beam into a desired shape or a desired size, and in turn, a desired illumination pupil luminance distribution is achieved.

Disclosure of Invention

It is an object of the present invention to provide an illumination optical apparatus capable of realizing illumination conditions with large variations in the shape and size of an illumination pupil luminance distribution. Another object of the present invention is to provide an exposure apparatus capable of performing good exposure under an appropriate illumination condition realized in accordance with pattern characteristics using an illumination optical apparatus that can realize an illumination condition with a large variation.

In order to achieve the above object, a first aspect of the present invention provides an illumination optical apparatus that illuminates illumination light to a mask on which a pattern is formed, the illumination optical apparatus including: a spatial light modulator, comprising: a plurality of reflection surfaces that reflect the illumination light, the plurality of reflection surfaces being individually controlled to form an intensity distribution of the illumination light in an illumination pupil of the illumination optical apparatus; a polarization unit that is disposed in an optical path of the illumination light and converts a polarization direction of the illumination light in the illumination pupil so that the illumination light is polarized in a circumferential direction; an optical integrator disposed in an optical path between the spatial light modulator and the illumination pupil; and a reflecting member including: a reflection surface different from the plurality of reflection surfaces, reflecting the illumination light; wherein the spatial light modulator and the reflecting member are: the illumination light traveling in a predetermined traveling direction is arranged so as to travel in a direction substantially parallel to the predetermined traveling direction after passing through the spatial light modulator and the reflection member.

A second aspect of the present invention provides an exposure apparatus that exposes a pattern formed on a mask to a substrate, the exposure apparatus comprising: the illumination optical apparatus described above illuminates the pattern.

A third aspect of the present invention provides an illumination method of illuminating illumination light with respect to a mask on which a pattern is formed, the illumination method comprising: reflecting the illumination light with a spatial light modulator having a plurality of reflective surfaces that can be individually controlled to form an intensity distribution of the illumination light in an illumination pupil; converting the polarization direction of the illumination light in the illumination pupil to a circumferential polarization state by a polarization unit disposed in the optical path of the illumination light; distributing the illumination light to the illumination pupil via an optical integrator arranged in an optical path between the spatial light modulator and the illumination pupil; and reflecting the illumination light by a reflecting member different from the spatial light modulator; wherein the illumination light traveling in a predetermined traveling direction is reflected by the spatial light modulator and the reflecting member so as to travel in a direction substantially parallel to the predetermined traveling direction after passing through the spatial light modulator and the reflecting member.

A fourth aspect of the present invention provides an exposure method of exposing a pattern formed on a mask to a substrate, the exposure method comprising: the pattern is illuminated using the illumination method described above.

A fifth aspect of the present invention provides a device manufacturing method of exposing a pattern formed on a mask onto a substrate using the above-described exposure apparatus; and developing the substrate with the pattern exposed.

A sixth aspect of the present invention provides a device manufacturing method of exposing a pattern formed on a mask onto a substrate using the above-described exposure method; and developing the substrate with the pattern exposed.

The illumination optical apparatus of the present invention can realize illumination conditions with large variations in the shape and size of the illumination pupil luminance distribution. The exposure apparatus of the present invention is capable of performing good exposure under appropriate illumination conditions realized in accordance with the pattern characteristics of the mask M using an illumination optical apparatus that can realize illumination conditions with large variations and thus manufacturing good devices.

Drawings

Fig. 1 is a diagram schematically showing the configuration of an exposure apparatus according to an embodiment of the present invention.

Fig. 2 is a diagram schematically showing the configuration of a spatial light modulation unit.

Fig. 3 is a perspective view schematically showing the configuration of a cylindrical micro fly-eye lens.

Fig. 4 is a diagram schematically showing a light intensity distribution of a quadrupole shape formed on a pupil plane of an afocal lens in an embodiment.

Fig. 5 is a diagram schematically showing an example of an illumination pupil luminance distribution forming a pentapole shape in the embodiment.

Fig. 6 is a diagram schematically showing a configuration of a spatial light modulation unit according to a modified example, in which an optical splitter and an optical combiner include a common polarization beam splitter.

Fig. 7 is a diagram schematically showing the configuration of a spatial light modulation unit according to another modified example having a transmissive spatial light modulator.

Fig. 8 is a diagram schematically showing the configuration of an exposure apparatus according to a modified example having a polarization control unit.

Fig. 9 is a diagram schematically showing a main configuration of a modified example using a diffractive optical element as a beam splitter.

Fig. 10 is a diagram schematically showing the configuration of the spatial light modulation unit shown in fig. 9.

Fig. 11 is a partial perspective view of a spatial light modulator in the spatial light modulation unit shown in fig. 9.

Fig. 12 is a diagram schematically showing a main configuration of a modified example using a prism unit as a beam splitter.

Fig. 13 is a flowchart showing the manufacturing steps of the semiconductor device.

Fig. 14 is a flow chart showing steps of manufacturing a liquid crystal device (e.g., a liquid crystal display device).

Detailed Description

Embodiments of the present invention will be described on the basis of the accompanying drawings. Fig. 1 is a diagram schematically showing the configuration of an exposure apparatus according to an embodiment of the present invention. Fig. 2 is a diagram schematically showing the configuration of a spatial light modulation unit. In fig. 1, the Z axis is provided along the normal direction of the photosensitive substrate, i.e., the wafer W, the Y axis is provided in the surface of the wafer W along a direction parallel to the plane of fig. 1, and the X axis is provided in the surface of the wafer W along a direction perpendicular to the plane of fig. 1.

Referring to fig. 1, the exposure apparatus of the present embodiment is provided with a light source 1 for supplying exposure light (illumination light). The light source 1 may be, for example, an ArF excimer laser light source supplying light having a wavelength of 193nm, or a KrF excimer laser light source supplying light having a wavelength of 248 nm. Light emitted from the light source 1 is expanded by the shaping optical system 2 into a beam having a desired sectional shape, and then the expanded beam is incident on the spatial light modulation unit 3.

As shown in fig. 2, the spatial light modulation unit 3 has a pair of prism members 31 and 32 and a pair of spatial light modulators 33 and 34. The light incident into the incident surface 31a of the prism member 31 in the spatial light modulation unit 3 along the optical axis AX propagates inside the prism member 31 and then is irradiated onto the polarization separation film 35 formed between the prism members 31 and 32. The S-polarized light reflected by the polarization separation film 35 propagates inside the prism member 31 and then is irradiated onto the first spatial light modulator 33.

The first spatial light modulator 33 has a plurality of mirror elements (substantially optical elements) 33a arranged two-dimensionally and a driving unit 33b (not shown in fig. 1) that individually controls and drives the postures of the respective mirror elements 33 a. Similarly, the second spatial light modulator 34 has a plurality of mirror elements 34a arranged two-dimensionally and a driving unit 34b (not shown in fig. 1) that individually controls and drives the postures of the respective mirror elements 34 a. The drive units 33b, 34b individually control and drive the postures of the mirror elements 33a, 34a according to commands from a control unit not depicted.

The light reflected by the mirror element 33a of the first spatial light modulator 33 propagates inside the prism member 31, and then is incident in the S-polarization state on the polarization separation film 36 formed between the prism members 31 and 32. The light having traveled through the first spatial light modulator 33 to be reflected on the polarization separation film 36 propagates inside the prism member 31, and then is emitted from the exit surface 31b of the prism member 31 to the outside of the spatial light modulation unit 3. In a standard state in which the reflective surfaces of all the mirror elements 33a in the first spatial light modulator 33 are positioned along the XY plane, the light having traveled along the optical axis AX into the spatial light modulation unit 3 and then passing through the first spatial light modulator 33 is emitted from the spatial light modulation unit 3 along the optical axis AX.

On the other hand, the P-polarized light that has passed through the polarization separation film 35 propagates inside the prism member 32, and is totally reflected on the interface 32a between the prism member 32 and the gas (air or inert gas) 37. Thereafter, the totally reflected light is incident on the second spatial light modulator 34. The light rays reflected by the mirror elements 34a in the second spatial light modulator 34 propagate inside the prism member 32, and are totally reflected on the interface 32b between the prism member 32 and the gas 37. Then, the totally reflected light is incident on the polarization separation film 36 formed between the prism members 31 and 32 in the P-polarization state.

The light that has traveled through the second spatial light modulator 34 and has been transmitted by the polarization separation film 36 propagates inside the prism member 31, and then is emitted from the exit surface 31b of the prism member 31 to the outside of the spatial light modulation unit 3. In a standard state in which the reflective surfaces of all the mirror elements 34a in the second spatial light modulator 34 are positioned along the XY plane, a light ray that has traveled along the optical axis AX into the spatial light modulation unit 3 and then passed through the second spatial light modulator 34 is emitted from the spatial light modulation unit 3 along the optical axis AX.

In the spatial light modulation unit 3, as described above, the polarization separation film 35 formed between the prism members 31 and 32 constitutes a beam splitter to split an incident beam into two beams (substantially a plurality of beams). The polarization separation film 36 formed between the prism members 31 and 32 constitutes a light combiner to combine the beam having traveled through the first spatial light modulator 33 with the beam having traveled through the second spatial light modulator 34.

The light emitted from the spatial light modulation unit 3 is then incident on the afocal lens 4. The afocal lens 4 is an afocal system (afocal optical system) that is set so that the following occurs: its front focal point approximately coincides with the position of the mirror elements 33a of the first spatial light modulator 33 and approximately coincides with the position of the mirror elements 34a of the second spatial light modulator 34, and its rear focal point approximately coincides with the position of the predetermined plane 5 indicated by a broken line in the drawing.

Thus, the S-polarized beam that has traveled through the first spatial light modulator 33 forms, on the pupil plane of the afocal lens 4, for example, a light intensity distribution having a two-pole shape in the Z direction, which is composed of two circular light intensity distribution areas centered on the optical axis AX spaced apart in the Z direction, and then the S-polarized beam is emitted from the afocal lens 4 with a two-pole (dipole) angular distribution. On the other hand, the P-polarized beam that has traveled through the second spatial light modulator 34 forms, on the pupil plane of the afocal lens 4, a light intensity distribution having, for example, a two-pole shape in the X direction, which is composed of two circular light intensity distribution regions centered on the optical axis AX that are spaced apart in the X direction, and then the P-polarized beam is emitted from the afocal lens 4 with a two-pole angle distribution.

The conical turning mirror system 6 is arranged at a position of a pupil plane of the afocal lens 4 or a position near the pupil plane position in an optical path between the front lens unit 4a and the rear lens unit 4b of the afocal lens 4. The configuration and action of the conical axicon system 6 will be described later. The beam having passed through the afocal lens 4 travels through the zoom lens 7 to cause a change in σ value (σ value = mask-side numerical aperture of illumination optics/mask-side numerical aperture of projection optics) and then enters the cylindrical micro fly's eye lens 8.

As shown in fig. 3, the cylindrical micro fly-eye lens 8 is composed of a first fly-eye part 8a disposed on the light source side and a second fly-eye part 8b disposed on the mask side. Cylindrical lens groups 8aa and 8ba arrayed in the X direction are each formed at a pitch p1 in the light source-side surface of the first fly-eye member 8a and in the light source-side surface of the second fly-eye member 8b, respectively. Cylindrical lens groups 8ab and 8bb arrayed in the Z direction are formed at a pitch p2(p2 > p1) in the mask-side surface of the first fly-eye section 8a and in the mask-side surface of the second fly-eye section 8b, respectively.

When focusing on the refraction action in the X direction of the cylindrical micro fly-eye lens 8 (that is, the refraction action in the XY plane), the wavefront (wave-front) of the parallel beam incident along the optical axis AX is divided by the cylindrical lens group 8aa formed on the light source side of the first fly-eye member 8a in the X direction at the pitch p1, the divided beams are condensed by the refraction surfaces of the cylindrical lens group, the condensed beams are then condensed by the refraction surfaces of the respective cylindrical lenses in the cylindrical lens group 8ba formed on the light source side of the second fly-eye member 8b, and the condensed beams are condensed on the back focal plane of the cylindrical micro fly-eye lens 8.

When focusing on the refraction action in the Z direction (that is, the refraction action in the YZ plane) of the cylindrical micro fly-eye lens 8, the wavefront of the parallel beam incident along the optical axis AX is split by the cylindrical lens group 8ab formed on the mask side of the first fly-eye member 8a in the Z direction at the pitch p2, the split beam is condensed by the refraction surfaces of the cylindrical lens group, the condensed beam is then condensed by the refraction surfaces of the respective cylindrical lenses in the cylindrical lens group 8bb formed on the mask side of the second fly-eye member 8b, and the condensed beam is condensed on the back focal plane of the cylindrical micro fly-eye lens 8.

As described above, the cylindrical micro fly-eye lens 8 is composed of the first fly-eye member 8a and the second fly-eye member 8b in each of which cylindrical lens groups are arranged on both side faces thereof, and the cylindrical micro fly-eye lens 8 performs the same optical function as a micro fly-eye lens in which a large number of micro refraction surfaces of a rectangular shape having a size p1 in the X direction and a size p2 in the Z direction are integrally formed in the horizontal direction and the vertical direction and densely. The cylindrical micro fly's eye lens 8 is capable of realizing a small change in distortion (distortion) due to a change in the surface shape of the micro-refractive surface, and, for example, keeping the influence on the illuminance distribution caused by a manufacturing error of a large number of micro-refractive surfaces integrally formed by etching small.

The position of the predetermined plane 5 is located in the vicinity of the front focus of the zoom lens 7, and the incident surface of the cylindrical micro fly-eye lens 8 is located in the vicinity of the rear focus of the zoom lens 7. In other words, the zoom (zoom) lens 7 substantially puts the predetermined plane 5 and the incident surface of the cylindrical micro fly-eye lens 8 into fourier transform relation, and thus keeps the pupil plane of the afocal lens 4 substantially optically conjugate with the incident surface of the cylindrical micro fly-eye lens 8.

Thus, for example, a quadrupole illumination field consisting of two circular light intensity distribution regions centered on the optical axis AX spaced apart in the Z direction and two circular light intensity distribution regions centered on the optical axis AX spaced apart in the X direction is formed on the incident surface of the cylindrical micro fly-eye lens 8 (as on the pupil plane of the afocal lens 4). The overall shape of this quadrupole illumination field varies similarly depending on the focal length of the zoom lens 7. The rectangular micro-refraction surface as the wavefront dividing unit in the cylindrical micro-fly's eye lens 8 has a rectangular shape similar to the shape of the illumination field to be formed on the mask M (and thus similar to the shape of the exposure area to be formed on the wafer W).

The beam incident on the cylindrical micro fly-eye lens 8 is two-dimensionally divided to form, on or near its back focal plane (and hence on the illumination pupil), a kind of secondary light source having a light intensity distribution substantially the same as that of the illumination field formed by the incident beam, that is, a quadrupole-shaped (quadrupole illumination pupil luminance distribution) secondary light source composed of two circular substantial surface illuminants spaced apart in the Z direction with centers on the optical axis AX and two circular substantial surface illuminants spaced apart in the X direction with centers on the optical axis AX. The beam from the secondary light source formed on or near the back focal plane of the cylindrical micro fly's eye lens 8 is then incident on an aperture stop (aperture stop)9 located in the vicinity thereof.

The aperture stop 9 has a quadrupole aperture (light transmitting portion) corresponding to a quadrupole-shaped secondary light source formed on or near the back focal plane of the cylindrical micro fly-eye lens 8. The aperture stop 9 is configured so as to be detachable with respect to the illumination optical path, and is switchable with a plurality of aperture stops having apertures of different sizes and shapes. The method of switching the aperture stop may be, for example, a known turret (turret) method or a sliding method. The aperture stop 9 is arranged at a position substantially optically conjugate to an entrance pupil plane of the projection optical system PL described later, and defines the range of the secondary light source contributing to illumination.

The beam from the secondary light source limited by the aperture stop 9 travels through a condensing optical system 10 to overlappingly illuminate a mask shutter (blind) 11. In this way, a rectangular-shaped illumination field according to the shape and focal length of the rectangular micro-refractive surface as the wavefront dividing unit of the cylindrical micro fly-eye lens 8 is formed on the mask shutter 11 as the illumination field stop. The beams having passed through the rectangular apertures (light transmitting portions) of the mask shutters 11 are condensed by the imaging optical system 12 to overlappingly illuminate the mask M on which a predetermined pattern is formed. That is, the imaging optical system 12 forms an image of the rectangular aperture of the mask shutter 11 on the mask M.

The beam having passed through the mask M held on the mask stage MS travels through the projection optical system PL to form an image of a mask pattern on the wafer (photosensitive substrate) W held on the wafer stage WS. In this way, by performing a single (one-shot) exposure or scanning exposure to simultaneously two-dimensionally drive and control the wafer stage WS in a plane (XY plane) perpendicular to the optical axis AX of the projection optical system PL and thus the wafer W simultaneously two-dimensionally, the pattern of the mask M is sequentially transferred into each of the exposure regions on the wafer W.

A conical axicon (conical axicon) system 6 is composed of the following components arranged in the order named from the light source side: a first prism member 6a having a plane on the light source side and a concave conical-shaped refractive surface on the mask side; and a second prism member 6b, a plane being on the mask side and a convex conical-shaped refracting surface being on the light source side. The concave conical refractive surface of the first prism member 6a and the convex conical refractive surface of the second prism member 6b are complementarily formed so as to be able to contact each other. At least one of the first prism member 6a and the second prism member 6b is configured to be movable along the optical axis AX, thereby making a space between the concave conical refractive surface of the first prism member 6a and the convex conical refractive surface of the second prism member 6b variable. For easier understanding, the action of the conical axicon system 6 and the action of the zoom lens 7 will be described with emphasis on a quadrupole or annular (annular) shaped secondary light source.

In a state where the concave conical refractive surface of the first prism member 6a and the convex conical refractive surface of the second prism member 6b are in contact with each other, the conical axicon system 6 functions as a plane parallel plate and does not exert an influence on the formed quadrupole or annular-shaped secondary light source. However, when the concave conical refractive surface of the first prism member 6a and the convex conical refractive surface of the second prism member 6b are separated from each other, the outer diameter (inner diameter) of the quadrupole or annular secondary light source is changed while keeping constant the width of the quadrupole or annular secondary light source (half of the difference between the diameter (outer diameter) of the circle circumscribing the quadrupole secondary light source and the diameter (inner diameter) of the circle inscribed in the quadrupole secondary light source; half of the difference between the outer diameter and the inner diameter of the annular secondary light source). That is, the annular ratio (inside diameter/outside diameter) and size (outside diameter) of the quadrupole or annular secondary light source are varied.

The zoom lens 7 has a function of similarly (or isotropically) magnifying or reducing the overall shape of the quadrupole or annular secondary light source. For example, the overall shape of the quadrupole or annular secondary light source is similarly enlarged as the focal length of the zoom lens 7 increases from a minimum value to a predetermined value. In other words, by the action of the zoom lens 7, both the width and the size (outer diameter) of the secondary light source are changed, while the annular ratio of the quadrupole or annular secondary light source is not changed. In this way, the annular ratio and size (outer diameter) of the quadrupole or annular secondary light source can be controlled by the action of the conical turning mirror system 6 and the zoom lens 7.

In the present embodiment, the spatial light modulators 33, 34 to be used may be, for example, spatial light modulators that continuously change each of the orientations of the two-dimensionally arranged mirror elements 33a, 34 a. Such spatial light modulators may be selected from, for example, the spatial light modulators disclosed in: japanese patent laid-open application No. 10-503300 (translation of PCT application) and its corresponding European patent application publication No. EP779530, Japanese patent laid-open application No. 2004-5278136 and its corresponding U.S. patent No. 6,900,915, Japanese patent laid-open application (translation of PCT application) No. 2006-524349 and its corresponding U.S. patent No. 7,095,546, and Japanese patent laid-open application No. 2006-113437. It is also possible to control the orientation of the two-dimensionally arranged mirror elements 33a, 34a in a plurality of discrete steps.

In the first spatial light modulator 33, each of the postures of the mirror elements 33a is changed by the action of the driving unit 33b operating in accordance with a control signal from the control unit, thereby setting each mirror element 33a to a predetermined orientation. As shown in fig. 4, the S-polarized light reflected by the mirror elements 33a of the first spatial light modulator 33 at respective predetermined angles forms, on the pupil plane of the afocal lens 4, for example, two circular light intensity distribution areas 41a and 41b spaced apart in the Z direction and centered on the optical axis AX. The light rays forming the light intensity distribution regions 41a and 41b have a polarization direction along the X direction, as indicated by the double-headed arrows in the drawing.

Similarly, in the second spatial light modulator 34, each of the postures of the mirror elements 34a is changed by the action of the driving unit 34b operating in accordance with a control signal from the control unit, whereby each mirror element 34a is set to a predetermined orientation. As shown in fig. 4, the p-polarized light reflected at respective predetermined angles by the mirror elements 34a of the second spatial light modulator 34 forms, on the pupil plane of the afocal lens 4, for example, two circular light intensity distribution regions 41c and 41d spaced apart in the X direction and centered on the optical axis AX. The light rays forming the light intensity distribution regions 41c and 41d have a polarization direction along the Z direction, as indicated by the double-headed arrows in the drawing. When the polarization state of the beam incident into the spatial light modulation unit 3 is circular polarization or linear polarization having a polarization direction at an angle of 45 ° to the X axis and the Z axis (which will be referred to as "45 ° linear polarization" hereinafter), the light intensities of the four light intensity distribution regions 41a to 41d become equal to each other.

The light rays forming the quadrupole light intensity distribution 41 on the pupil plane of the afocal lens 4 form a light intensity distribution having a quadrupole shape corresponding to the light intensity distribution regions 41a to 41d on the entrance surface of the cylindrical micro fly-eye lens 8 and on the illumination pupil (the position where the aperture stop 9 is arranged) on or near the back focal plane of the cylindrical micro fly-eye lens 8. That is, the afocal lens 4, the zoom lens 7, and the cylindrical micro fly's eye lens 8 constitute a distribution forming optical system that forms a predetermined light intensity distribution on the illumination pupil of the illumination optical apparatus (2-12) based on the beam that has traveled through the first spatial light modulator 33 and the second spatial light modulator 34. Further, light intensity distributions having quadrupole shapes corresponding to the light intensity distribution regions 41a to 41d are also formed at other illumination pupil positions optically conjugate to the aperture stop 9, that is, at the pupil position of the imaging optical system 12 and the pupil position of the projection optical system PL.

The exposure apparatus performs exposure under appropriate illumination conditions in accordance with the pattern characteristics so as to transfer the pattern of the mask M onto the wafer W with high accuracy and faithfulness. In the present embodiment, the illumination pupil luminance distribution to be formed is a quadrupole illumination pupil luminance distribution corresponding to the quadrupole light intensity distribution 41 shown in fig. 4, and the beam passing through this quadrupole illumination pupil luminance distribution is set in the circular polarization state. In the circularly polarized quadrupole illumination based on the quadrupole illumination pupil luminance distribution in the circularly polarized state, the light irradiated onto the wafer W as the final illumination target surface is in a polarized state in which the principal component is S-polarized light.

Here, the S-polarized light is linearly polarized light having a polarization direction along a direction perpendicular to the plane of incidence (it is polarized light in which an electric vector vibrates in a direction perpendicular to the plane of incidence). The incident plane is defined as a plane including a point on the boundary surface (illumination target surface: surface of wafer W) of the medium irradiated with the light ray and including the point formed by the normal line of the boundary surface and the incident direction of the light ray. As a result, the circularly polarized quadrupole illumination achieves an improvement in the optical performance (depth of field and others) of the projection optical system, thereby obtaining a good mask pattern image with high contrast on the wafer (photosensitive substrate).

Since the present embodiment uses the spatial light modulation unit 3 having the pair of (pair) spatial light modulators 33, 34 in which the postures of the mirror elements 33a, 34a are individually changed, it is possible to freely and quickly change the illumination pupil luminance distribution composed of the first light intensity distribution formed on the illumination pupil in the S-polarization state by the action of the first spatial light modulator 33 and the second light intensity distribution formed on the illumination pupil in the P-polarization state by the action of the second spatial light modulator 34. In other words, the present embodiment can realize an illumination condition having a large variation in the shape, size, and polarization state of the illumination pupil luminance distribution by changing each of the shapes and sizes of the first light intensity distribution and the second light intensity distribution in mutually different polarization states.

As described above, in the present embodiment, the illumination optical apparatuses (2 to 12) to illuminate the mask M as the illumination target surface on the basis of the light rays from the light source 1 can realize the illumination conditions having large variations in the shape, size, and polarization state of the illumination pupil luminance distribution. Further, the exposure apparatus (1-WS) of the present embodiment is capable of performing good exposure under appropriate illumination conditions realized in accordance with the pattern characteristics of the mask M using illumination optical apparatuses (2-12) that can realize illumination conditions with large variations.

In the present embodiment, when the spatial light modulators 33 and 34 are in the standard state, the traveling direction of the beam incident to the polarization separation film 35 serving as the beam splitter is parallel to (or coincides with) the traveling direction of the beam exiting from the polarization separation film 36 serving as the light combiner. In other words, in the standard state of the spatial light modulators 33 and 34, the traveling directions of the beam incident to the spatial light modulation unit 3 and the beam exiting from the spatial light modulation unit 3 are coincident with (or parallel to) the optical axis AX of the illumination optical apparatus. Since the optical paths upstream and downstream of the spatial light modulation unit 3 are coaxial (or parallel), the optical system can be shared with, for example, a conventional illumination optical apparatus that uses a diffractive optical element to form an illumination pupil luminance distribution.

In the present embodiment, the mirror elements 33a of the first spatial light modulator 33 are arranged near the prism member 31, and the mirror elements 34a of the second spatial light modulator 34 are arranged near the prism member 32. In this case, the prism members 31, 32 function as masking members for the mirror elements 33a, 34a, which can enhance the durability of the spatial light modulators 33, 34.

In the present embodiment, the spatial light modulation unit 3 may be designed such that the incident angle θ (see fig. 2) of light to the polarization separation film 35 formed between the prism members 31 and 32 is close to the Brewster's angle. This configuration can reduce reflection of P-polarized light on the polarization separation film 35 and increase polarization efficiency. The polarization separation films 35, 36 are not limited to polarization separation films made of dielectric multilayer films, but may be, for example, polarization separation films having a "polarization separation layer of a periodic grating (grating) structure". This type of "polarization separation layer of periodic grating structure" may be a wire grid type (wire grid) polarization separation element in which a plurality of metal gratings parallel to a first direction are periodically arranged in a second direction orthogonal to the first direction. This technique is disclosed, for example, in Japanese patent laid-open application No. 2005-77819 and its corresponding U.S. patent No. 7,116,478.

In the above-described embodiment, the spatial light modulation unit 3 is composed of the pair of prism members 31 and 32 and the pair of spatial light modulators 33 and 34. However, it is not necessarily limited thereto, and various forms for the specific configuration of the spatial light modulation unit 3 may be covered.

In the foregoing embodiments, the afocal lens 4, the conical axicon system 6, and the zoom lens 7 are arranged in the optical path between the spatial light modulation unit 3 and the cylindrical micromirror fly-eye lens 8. However, without necessarily being limited thereto, these optical components may be replaced by, for example, a condensing optical system serving as a fourier transform lens.

In the foregoing embodiment, the P-polarized light that has passed through the polarization separation film 35 serving as a beam splitter is folded toward the second spatial light modulator 34 by total reflection (total reflection) on the interface 32a as the first folding surface between the prism member 32 and the gas 37. Also, the P-polarized light that has traveled through the second spatial light modulator 34 is folded toward the polarization separation film 36 serving as a light combiner by total reflection on the interface 32b between the prism member 32 and the gas 37. However, it is not necessarily limited thereto, and a reflective film may be provided on the interfaces 32a, 32 b.

In the above description, the quadrupole illumination pupil luminance distribution is formed by: the two-pole light intensity distribution regions 41a, 41b in the Z direction are formed by the action of the first spatial light modulator 33, and the two-pole light intensity distribution regions 41c, 41d in the X direction are formed by the action of the second spatial light modulator 34. However, in the present embodiment, as described above, various forms regarding the shape, size, and polarization state of the illumination pupil luminance distribution can be covered. An example of forming a penta-polar illumination pupil luminance distribution will be schematically described below with reference to fig. 5.

In this example, as shown in the left side view in fig. 5, by way of example, two circular light intensity distribution regions 42a and 42b centered on the optical axis AX and a circular light intensity distribution region 42c' centered on the optical axis AX, which are spaced apart in the Z direction, are formed on the pupil plane of the afocal lens 4 by the action of the first spatial light modulator 33. The light rays forming the light intensity distribution regions 42a, 42b, and 42c' have a polarization direction along the X direction, as indicated by the double-headed arrows in the drawing. On the other hand, as shown in the middle view in fig. 5, by way of example, two circular light intensity distribution regions 42d and 42e centered on the optical axis AX and a circular light intensity distribution region 42c ″ centered on the optical axis AX, which are spaced apart in the X direction, are formed on the pupil plane of the afocal lens 4 by the action of the second spatial light modulator 34. The light rays forming the light intensity distribution regions 42d, 42e, and 42c ″ have a polarization direction along the Z direction, as indicated by the double-headed arrows in the drawing.

As a result, as shown in the right side view in fig. 5, the penta-pole shaped light intensity distribution areas 42a to 42e are formed on the pupil plane of the afocal lens 4. A circular light intensity distribution region 42c centered on the optical axis AX is formed by the overlap of the light intensity distribution regions 42c' and 42c ″. When an optical path length difference not smaller than the temporal coherence (temporal coherence) length of the light source 1 is provided between the S-polarized light traveling through the first spatial light modulator 33 to the pupil plane of the afocal lens 4 and the P-polarized light traveling through the second spatial light modulator 34 to the pupil plane of the afocal lens 4, the beam having the polarization direction along the Z direction and the beam having the polarization direction along the X direction (as indicated by the double-headed arrow in the drawing) pass through the region of the light intensity distribution region 42 c.

In contrast, when there is no path length difference between the S-polarized light traveling through the first spatial light modulator 33 to the pupil plane of the afocal lens 4 and the P-polarized light traveling through the second spatial light modulator 34 to the pupil plane of the afocal lens 4, the polarization state of the beam passing through the region of the light intensity distribution area 42c coincides with the polarization state of the beam incident to the spatial light modulation unit 3. When the polarization state of the beam incident to the spatial light modulation unit 3 is circular polarization or 45 ° linear polarization, the light intensities of the four peripheral light (surrounding light) intensity distribution regions 42a, 42b, 42d, 42e are equal to each other, and the light intensity of the central light intensity distribution region 42c is twice as high as that of the other regions.

As another example, light having passed through a half-wave plate (wave plate) may be made incident on the polarization separation film 35 serving as a beam splitter. The ratio of the intensities of the S-polarized light and the P-polarized light separated by the polarization separation film 35 can be controlled by rotating the half-wave plate disposed on the light source side about the optical axis with respect to the polarization separation film 35. That is, it is possible to control the ratio of the intensities of the S-polarized light and the P-polarized light reaching the pupil plane of the afocal lens 4. It is also possible to have only S-polarized light or P-polarized light reach the pupil plane of the afocal lens 4, for example, by: the rotation angle of the half-wave plate is controlled so that S-polarized light is incident to the polarization separation film 35 or the rotation angle of the half-wave plate is controlled so that P-polarized light is incident to the polarization separation film 35. This permits a two-pole light intensity distribution (e.g., light intensity distribution areas 41a, 41b in fig. 4) to be formed on the pupil plane of the afocal lens 4.

In the foregoing embodiment, the polarization separation film 35 located on the light splitting surface functions as a light splitter, and the polarization separation film 36 located at a position different from the position of the polarization separation film 35 on the light combining surface functions as a light combiner. However, it is not necessarily limited thereto, and it is also possible to employ a modified example in which the beam splitter and the optical combiner have a common polarization beam splitter 51 (for example, as shown in fig. 6). In the spatial light modulation unit 3A shown in the modified example of fig. 6, of the light incident to the polarization beam splitter 51 along the optical axis AX, the S-polarized light reflected on the polarization separation film 51a travels to pass through the quarter wave plate 52 to become the circularly polarized light, and the circularly polarized light is incident to the first spatial light modulator 53.

The light reflected by the plurality of mirror elements of the first spatial light modulator 53 is changed into P-polarized light after traveling through the quarter wave plate 52, and the P-polarized light is returned to the polarization beam splitter 51. The P-polarized light that has traveled through the first spatial light modulator 53 and entered the polarization beam splitter 51 passes through the polarization separation film 51a to be emitted from the polarization beam splitter 51. In the standard state of the first spatial light modulator 53, the light that has traveled along the optical axis AX into the spatial light modulation unit 3A and then through the first spatial light modulator 53 is emitted along the optical axis AX from the spatial light modulation unit 3A.

On the other hand, the P-polarized light passing through the polarization separation film 51a of the polarization beam splitter 51 travels through the quarter wave plate 54 to become circularly polarized light, and the circularly polarized light is incident to the second spatial light modulator 55. The light reflected by the plurality of mirror elements of the second spatial light modulator 55 travels through the quarter wave plate 54 to become S-polarized light, and the S-polarized light returns to the polarization beam splitter 51. The S-polarized light that has traveled through the second spatial light modulator 55 and has entered the polarization beam splitter 51 is reflected by the polarization separation film 51a, and the reflected light is emitted from the polarization beam splitter 51. In the standard state of the second spatial light modulator 55, the light that has traveled along the optical axis AX into the spatial light modulation unit 3A and then through the second spatial light modulator 55 is emitted from the spatial light modulation unit 3A along the optical axis AX.

In the above description, a spatial light modulator having a plurality of optical elements which are two-dimensionally arranged and individually controlled is a spatial light modulator in which the orientation (angle: tilt angle) of a two-dimensionally arranged reflection surface can be individually controlled. However, it is not necessarily limited thereto, and it is also possible to use, for example, a spatial light modulator in which the heights (positions) of two-dimensionally arranged reflecting surfaces can be individually controlled. Spatial light modulators of this type suitable for use herein may be selected from, for example, the spatial light modulators disclosed in: japanese patent laid-open application No. 6-281869 and its corresponding U.S. patent No. 5,312,513, and Japanese patent laid-open application (translation of PCT application) No. 2004-520618 and its corresponding U.S. patent No. 6,885,493 are shown in FIG. 1 d. These spatial light modulators are capable of exerting the same effect as a diffractive surface on incident light by forming a two-dimensional height distribution. The above-described spatial light modulator having a plurality of reflective surfaces arranged two-dimensionally can be modified, for example, according to the disclosure in japanese patent laid-open application No. 2006-513442 and its corresponding U.S. patent No. 6,891,655 or according to the disclosure in japanese patent laid-open application No. 2005-524112 and its corresponding U.S. patent laid-open application No. 2005/0095749.

In the above description, the spatial light modulator used is a reflective spatial light modulator having a plurality of mirror elements, but is not necessarily limited thereto, and it is also possible to use, for example, a transmissive spatial light modulator disclosed in U.S. Pat. No. 5,229,872. Fig. 7 schematically shows a configuration of a spatial light modulation unit according to a modification example with a transmissive spatial light modulator. In the spatial light modulation unit 3B shown in the modified example of fig. 7, of the light incident on the polarization beam splitter 61 serving as a beam splitter along the optical axis AX, the S-polarized light reflected by the polarization separation film 61a is incident on the first spatial light modulator 62.

The light rays that have passed through the plurality of optical elements (prism elements or the like) of the first spatial light modulator 62 are folded by the path folding mirror 63, and then the folded light is incident on the polarization beam splitter 64 serving as a light combiner. The S-polarized light that has traveled through the first spatial light modulator 62 and has entered the polarization beam splitter 64 is reflected by the polarization separation film 64a, and the reflected light is emitted from the polarization beam splitter 64. In the standard state of the first spatial light modulator 62, the light that has traveled along the optical axis AX into the spatial light modulation unit 3B and then through the first spatial light modulator 62 is emitted from the spatial light modulation unit 3B along the optical axis AX.

The P-polarized light having passed through the polarization separation film 61a of the polarization beam splitter 61 is incident into the second spatial light modulator 65. The light having passed through the plurality of optical elements of the second spatial light modulator 65 is folded by the path folding mirror 66, and the folded light is incident to the polarization beam splitter 64. The P-polarized light that has traveled through the second spatial light modulator 65 and has entered the polarization beam splitter 64 travels through the polarization separation film 64a and is emitted from the polarization beam splitter 64. In the standard state of the second spatial light modulator 65, the light that has traveled along the optical axis AX into the spatial light modulation unit 3B and then through the second spatial light modulator 65 is emitted from the spatial light modulation unit 3B along the optical axis AX.

In the above description, the optical system is configured such that light from the light source 1 supplied with light in a polarization state in which linearly polarized light is a main component is guided to the spatial light modulation unit (3; 3A; 3B) while the polarization state of the light is substantially maintained, but it is also possible, for example, to employ a modification example in which a polarization control unit 13 for making the polarization state of existing light variable is provided on the light source 1 side of the spatial light modulation unit 3 in the optical path (as shown in fig. 8). In fig. 8, components having the same functionality as in fig. 1 are indicated by the same reference signs.

The polarization control unit 13 shown in the modified example of fig. 8 receives light that has passed through the shaping optical system 2 and the path folding mirror from the light source 1, and emits light in a desired polarization state toward the spatial light modulation unit 3. The polarization control unit 13 is composed of, for example, a half-wave plate 13a arranged to be rotatable about the optical axis or about an axis parallel to the optical axis and a rotation drive unit 13b rotationally driving the half-wave plate 13 a.

For example, by rotationally adjusting the half-wave plate 13a with the rotation driving unit 13b, the linearly polarized light having the polarization direction (the direction of the electric field) in the XZ plane along the direction at 45 ° to the X axis or the Z axis can be supplied to the spatial light modulation unit 3. At this time, the light flux of the S-polarized light (light traveling toward the first spatial light modulator 33) and the light flux of the P-polarized light (light traveling toward the second spatial light modulator 34) separated by the polarization separation film of the spatial light modulation unit 3 become approximately equal.

By the rotation adjustment of the half-wave plate 13a in the polarization control unit 13, it is possible to set the ratio of the light fluxes of the S-polarized light (light traveling toward the first spatial light modulator 33) and the P-polarized light (light traveling toward the second spatial light modulator 34) separated by the polarization separation film of the spatial light modulation unit 3 to any light flux ratio. For example, in the case where the quadrupole light intensity distribution regions 41a to 41d as shown in fig. 4 are formed, the ratio of the light intensities of the two light intensity distribution regions 41a, 41b spaced apart in the Z direction and centered on the optical axis AX to the light intensities of the two light intensity distribution regions 41c, 41d spaced apart in the X direction and centered on the optical axis AX may be set as the desired light flux ratio.

In the modified example shown in fig. 8, the apparatus may be arranged such that the illumination pupil polarization distribution is measured by the pupil polarization distribution measuring device 14 and the polarization control unit 13 is controlled according to the result of the measurement. In this case, each spatial light modulator in the spatial light modulation unit can be controlled as occasion demands. This pupil polarization distribution measuring apparatus 14 is an apparatus that is provided in a wafer stage WS for holding a wafer W or in a measurement stage provided separately from the wafer stage WS and that measures the polarization state of illumination light (exposure light) incident on the wafer W in a pupil (or aperture). The detailed configuration and operation of the pupil polarization distribution measuring apparatus 14 are disclosed in, for example, japanese patent laid-open application No. 2005-5521.

This configuration is effective, as follows: for example, even when there is a reflection difference between polarizations of each path folding mirror arranged in the illumination optical system or the projection optical system, adverse effects caused thereby can be prevented. In the modified example of fig. 8, the direction of polarization to the spatial light modulation unit 3 is adjusted by the polarization control unit 13, but the same effect can be achieved by rotating the light source 1 itself or the spatial light modulation unit 3 around the optical axis. This polarization control unit 13 is also applicable to the modified examples shown in fig. 6 and 7.

In the foregoing embodiments and the modified examples of fig. 6 to 8, the beam splitter and the light combiner have the polarization separation films (35, 36; 51 a; 61a, 64a), but are not necessarily limited thereto, and it is also possible to adopt a configuration in which the beam splitter and the light combiner have the separation films to achieve the amplitude division of the beam. In this case, it becomes feasible that the first light intensity distribution formed on the illumination pupil by the action of the first spatial light modulator and the second light intensity distribution formed on the illumination pupil by the action of the second spatial light modulator have the same polarization state, but that the illumination condition having a large variation in the shape and size of the illumination pupil luminance distribution is realized by changing each of the shapes and sizes of the first light intensity distribution and the second light intensity distribution.

In the foregoing embodiment and the modified examples of fig. 6 to 8, the polarization separation film (35; 51 a; 61a) is used to split the incident radiation beam into two radiation beams, but it is not necessarily limited thereto, and it is also possible to adopt, for example, a configuration in which the incident radiation beam is split into two radiation beams using a diffractive optical element. Fig. 9 is a diagram schematically showing a main configuration of a modified example using a diffractive optical element as a beam splitter. The modification example of fig. 9 has a configuration in which the spatial light modulation cell 3 in the embodiment of fig. 1 is replaced by a diffractive optical element 71, a condenser lens 72, a pair of half-wave plates 73A, 73B, and a pair of spatial light modulation cells 74A, 74B.

In the modified example of fig. 9, the beam from the light source 1 having traveled through the shaping optical system 2 is incident on the diffractive optical element 71 as a beam splitter along the optical axis AX. The diffractive optical element 71 has a function such that: when a parallel beam having a rectangular cross section is incident thereon along the optical axis AX, for example, it forms two rectangular light intensity distribution regions centered on the optical axis AX spaced apart in the Z direction in its far field (or Fraunhofer diffraction zone). In other words, the diffractive optical element 71 functions to split incident light into two beams.

The first of the two beams split by the diffractive optical element 71 travels through a condenser lens 72 acting as a fourier transform lens and then enters a half-wave plate 73A that is rotatable about an optical axis AXa of an optical path of the first beam or about an axis parallel to the optical axis AXa. The light in the linear polarization state having passed through the half-wave plate 73A travels through the spatial light modulation cell 74A and then travels through the front lens cell 4A of the afocal lens 4 to reach the pupil plane 4c of the afocal lens 4. On the other hand, the second beam of the two beams split by the diffractive optical element 71 travels through the condenser lens 72 and enters the half-wave plate 73B rotatable about the optical axis AXb of the optical path of the second beam or about an axis parallel to the optical axis AXb. The light in the linear polarization state having passed through the half-wave plate 73B travels through the spatial light modulation cell 74B and then travels through the front lens cell 4a of the afocal lens 4 to reach the pupil plane 4 c. The front lens unit 4A of the afocal lens 4 is an optical system that superimposes on the pupil plane 4c the beam that has passed through the spatial light modulator in the spatial light modulation unit 74A and the beam that has passed through the spatial light modulator in the spatial light modulation unit 74B and functions as a light combiner.

For the sake of brevity in the description, it is assumed hereinafter that the spatial light modulation cell 74A arranged in the optical path of the first beam and the spatial light modulation cell 74B arranged in the optical path of the second beam have the same configuration. It is also assumed that a parallel beam in a linearly polarized state with a polarization direction at 45 ° to the Z direction and the X direction is incident on the diffractive optical element 71, a light in a linearly polarized state in the X direction (transverse polarized state) with a polarization direction in the X direction is incident on the spatial light modulation cell 74A due to the action of the half-wave plate 73A, and a light in a linearly polarized state in the Z direction (vertical polarized state) with a polarization direction in the Z direction is incident on the spatial light modulation cell 74B due to the action of the half-wave plate 73B.

The specific configuration and action of the spatial light modulation unit 74A will be described below with reference to fig. 10 and 11. Since the spatial light modulation unit 74B basically has the same configuration as the spatial light modulation unit 74A, redundant description about the specific configuration and action of the spatial light modulation unit 74B is omitted. As shown in fig. 10, the spatial light modulation unit 74A has a prism 23b made of an optical material (e.g., fluorite) and a reflective spatial light modulator 23a attached close (in proximity) to a side 23ba of the prism 23b parallel to the XY plane. The optical material used for manufacturing the prism 23b is not necessarily limited to fluorite, but may be silica or any other optical material depending on the wavelength of the light supplied from the light source 1.

The prism 23b has a form obtained by replacing one side face of a rectangular parallelepiped (the side face opposite to the side face 23ba to which the spatial light modulator 23a is closely attached) with side faces 23bb and 23bc pressed in a V shape, and is also called a K prism due to a sectional shape along the YZ plane. The sides 23bb and 23bc of the prism 23b pressed into a V-shape are defined by two planes PN1 and PN2 intersecting at an obtuse angle. Both planes PN1 and PN2 are orthogonal to and form a V-shape along the YZ plane.

The inner surfaces of the two side surfaces 23bb and 23bc which are in contact along an intersection line (a straight line extending in the X direction) P3 between the two planes PN1 and PN2 serve as reflection surfaces Rl and R2. That is, the reflection surface Rl is located on the plane PN1, the reflection surface R2 is located on the plane PN2, and the angle between the reflection surface Rl and the R2 is an obtuse angle. As an example, the angle may be determined as follows: the angle between the reflective surfaces Rl and R2 is 120 °; the angle between the incident surface IP of the prism 23b perpendicular to the optical axis AXa and the reflection surface Rl is 60 °; an angle between the exit surface OP of the prism 23b perpendicular to the optical axis AXa and the reflection surface R2 is 60 °.

In the prism 23b, a side face 23ba to which the spatial light modulator 23a is closely attached is parallel to the optical axis AXa; and the reflection surface Rl is located on the light source 1 side (on the upstream side of the exposure apparatus; on the left side in fig. 10), and the reflection surface R2 is located on the afocal lens 4 side (on the downstream side of the exposure apparatus; on the right side in fig. 10). More specifically, the reflection surface Rl is arranged obliquely with respect to the optical axis AXa, and the reflection surface R2 is arranged obliquely with respect to the optical axis AXa and is symmetrical to the reflection surface R1 with respect to a plane passing through the intersection line P3 and parallel to the XZ plane. As described below, the side surface 23ba of the prism 23b is an optical surface opposite to the surface on which the plurality of mirror elements SE of the spatial light modulator 23a are arranged.

The reflection surface R1 of the prism 23b reflects the light incident through the incident surface IP toward the spatial light modulator 23 a. The spatial light modulator 23a is located in an optical path between the reflection surface R1 and the reflection surface R2, and reflects the light incident through the reflection surface R1. The reflection surface R2 of the prism 23b reflects the light ray incident through the spatial light modulator 23a to guide the reflected light to the front lens unit 4a of the afocal lens 4 through the exit surface OP. In fig. 10, to make the description thereof easier to understand, the optical path is extended so that the optical axis AXa linearly extends on the rear side of the spatial light modulation unit 74A. Fig. 10 shows an example in which the prism 23b is integrally made of one optical block, but the prism 23b may be constructed using a plurality of optical blocks.

The spatial light modulator 23a applies spatial modulation to the light incident through the reflection surface R1 according to the incident position of the light. As shown in fig. 11, the spatial light modulator 23a is provided with a plurality of micro mirror elements (optical elements) SE arranged two-dimensionally. For ease of description and illustration, fig. 10 and 11 show an example of a configuration in which the spatial light modulator 23a has sixteen mirror elements SE of a 4 x 4 matrix, but the spatial light modulator actually has a much larger number of mirror elements than sixteen elements.

Referring to fig. 10, of a beam of rays incident into the spatial light modulation unit 23 in a direction parallel to the optical axis AXa, a ray L1 is incident on a mirror element SEa among the plurality of mirror elements SE, and a ray L2 is incident on a mirror element SEa different from the mirror element SEa. Similarly, the ray L3 is incident on the mirror element SEc different from the mirror elements SEa, SEb, and the ray L4 is incident on the mirror element SEd different from the mirror elements SEa to SEc. The mirror elements SEa to SEd apply respective spatial modulations to the rays L1 to L4, respectively, depending on their positions.

The spatial light modulation unit 23 is configured such that, in a standard state in which the reflection surfaces of all the mirror elements SE of the spatial light modulator 23a are set to be parallel to the XY plane, a ray incident to the reflection surface R1 along a direction parallel to the optical axis AXa travels through the spatial light modulator 23a and is then reflected by the reflection surface R2 to a direction parallel to the optical axis AXa. Further, the spatial light modulation unit 23 is configured such that the air equivalent length from the incident surface IP of the prism 23b to the exit surface OP through the mirror elements SEa to SEd is equal to the air equivalent length from the position corresponding to the incident surface IP to the position corresponding to the exit surface OP without the prism 23b in the optical path. The air equivalent length herein is obtained by converting the optical path length in the optical system into the optical path length in air having a refractive index of 1, and the air equivalent length in the medium having a refractive index of n is obtained by multiplying the optical path length therein by 1/n.

The surfaces of the plurality of mirror elements SE formed with the spatial light modulator 23a in an array form are located at or near the back focal point of the condenser lens 72 and at or near the front focal point of the afocal lens 4. Therefore, a beam having a cross section of a shape (for example, a rectangular shape) according to the characteristics of the diffractive optical element 71 is incident to the spatial light modulator 23 a. The light rays reflected by the mirror elements SEa to SEd of the spatial light modulator 23a and having a predetermined angular distribution form predetermined light intensity distribution regions SP1 to SP4 on the pupil plane 4c of the afocal lens 4. That is, the front lens unit 4a of the afocal lens 4 converts the angle given to the outgoing light by the mirror elements SEa to SEd of the spatial light modulator 23a into a position on the far field region (fraunhofer diffraction region), i.e., the plane 4c, of the spatial light modulator 23 a.

Referring to fig. 1, the entrance surface of the cylindrical micro fly-eye lens 8 is located at or near a position optically conjugate to a pupil plane 4c (not shown in fig. 1) of the afocal lens 4. Therefore, the light intensity distribution (luminance distribution) of the secondary light source formed by the cylindrical micro fly-eye lens 8 is a distribution according to the light intensity distribution areas SP1 to SP4 formed on the pupil plane 4c by the spatial light modulator 23a and the front lens unit 4a of the afocal lens 4. The spatial light modulator 23a is a movable multi (multi) mirror including mirror elements SE which are a large number of micro-reflective elements regularly and two-dimensionally arranged along a plane with a planar-shaped reflective surface facing upward, as shown in fig. 11.

Each mirror element SE is movable, and the inclination of the reflecting surface (that is, the inclination angle and direction of the reflecting surface) of each mirror element SE is independently controlled by the action of a drive unit 23c (not shown in fig. 11) that operates according to a command from a control unit (not shown). Each mirror element SE can be rotated continuously or discretely by a desired rotation angle about each rotation axis along two directions (X-direction and Y-direction) orthogonal to each other and parallel to the reflective surface. That is, the tilt of the reflective surface of the respective mirror element SE can be controlled two-dimensionally.

In case the reflective surface of each mirror element SE is rotated discretely, a preferred switching control will cause the rotation angle to be switched in a plurality of stages (e.g. …, -2.5 °, -2.0 °, …,0 °, +0.5 °, …, +2.5 ° …). Fig. 11 shows the mirror element SE having a square-shaped outline, but the outline of the mirror element SE is not limited to a square. However, from the viewpoint of light utilization efficiency, the profile may be a shape that permits the implementation of an arrangement of mirror elements SE with as small a gap as possible (a shape that permits the closest packing). Further, the interval between two adjacent mirror elements SE may be the minimum necessary from the viewpoint of light utilization efficiency.

In the spatial light modulator 23a, the postures of the respective mirror elements SE are changed by the action of the driving unit 23c operating in accordance with the control signal from the control unit, thereby setting each mirror element SE to a predetermined orientation. Rays reflected by the mirror elements SE of the spatial light modulator 23a at respective predetermined angles travel through the afocal lens 4 and the zoom lens 7 to form a multipole-shaped (quadrupole, pentapole, … …) or another-shaped light intensity distribution (illumination pupil luminance distribution) on the illumination pupil at or near the back focus of the cylindrical micro fly-eye lens 8. This illumination pupil luminance distribution is similarly (isotropically) varied by the action of the zoom lens 7.

Specifically, the laterally polarized light reflected at respective predetermined angles by the mirror elements SE of the spatial light modulator 23a in the spatial light modulation unit 74A forms, for example, two circular light intensity distribution areas 41a and 41b on the optical axis AX at the center spaced in the Z direction on the pupil plane 4c of the afocal lens 4, as shown in fig. 4. The light rays forming the light intensity distribution regions 41a and 41b have a polarization direction along the X direction, as indicated by the double-headed arrows in the drawing.

Similarly, vertically polarized light reflected at respective predetermined angles by the mirror elements of the spatial light modulator in the spatial light modulation unit 74B forms, for example, two circular light intensity distribution regions 41c and 41d on the optical axis AX at centers spaced in the X direction on the pupil plane 4c of the afocal lens 4, as shown in fig. 4. The light rays forming the light intensity distribution regions 41c and 41d have a polarization direction along the Z direction, as indicated by the double-headed arrows in the drawing.

The light rays forming the quadrupole light intensity distribution 41 on the pupil plane 4c of the afocal lens 4 form quadrupole light intensity distribution regions corresponding to the light intensity distribution regions 41a to 41d on the entrance surface of the cylindrical micro fly-eye lens 8 and on the illumination pupil (the position where the aperture stop 9 is arranged) on or near the back focal plane of the cylindrical micro fly-eye lens 8. Further, quadrupole light intensity distribution regions corresponding to the light intensity distribution regions 41a to 41d are also formed at other illumination pupil positions optically conjugate with the aperture stop 9, that is, at the pupil position of the imaging optical system 12 and the pupil position of the projection optical system PL.

In another example, as shown in the left side view in fig. 5, the spatial light modulation unit 74A is used to form, for example, two circular light intensity distribution regions 42a and 42b spaced apart in the Z direction and centered on the optical axis AX and one circular light intensity distribution region 42c' centered on the optical axis AX on the pupil plane 4c of the afocal lens 4. The light rays forming the light intensity distribution regions 42a, 42b, 42c' have a polarization direction along the X direction, as indicated by the double-headed arrows in the drawing. On the other hand, as shown in the middle view in fig. 5, the spatial light modulation unit 74B is configured to form, for example, two circular light intensity distribution regions 42d and 42e spaced apart in the X direction and centered on the optical axis AX and one circular light intensity distribution region 42c ″ centered on the optical axis AX on the pupil plane 4c of the afocal lens 4. The light rays forming the light intensity distribution regions 42d, 42e, 42c ″ have a polarization direction along the Z direction, as indicated by the double-headed arrows in the drawing.

As a result, as shown in the right side view in fig. 5, the penta-pole shaped light intensity distribution areas 42a to 42e are formed on the pupil plane 4c of the afocal lens 4. A circular light intensity distribution region 42c centered on the optical axis AX is formed by overlapping the light intensity distribution regions 42c' and 42c ″. When an optical path length difference not smaller than the temporal coherence (temporal coherence) length of the light source 1 is provided between the horizontally polarized light having traveled through the spatial light modulation unit 74A to reach the pupil plane 4c of the afocal lens 4 and the vertically polarized light having traveled through the spatial light modulation unit 74B to reach the pupil plane of the afocal lens 4, the beam with the polarization direction along the Z direction and the beam with the polarization direction along the X direction pass through the region of the light intensity distribution region 42c, as indicated by the double-headed arrows in the drawing.

In the modification example of fig. 9, as described above, the illumination pupil luminance distribution composed of the first light intensity distribution in the lateral polarization state formed on the pupil plane by the action of the spatial light modulator in the spatial light modulation unit 74A and the second light intensity distribution in the vertical polarization state formed on the pupil plane by the action of the spatial light modulator in the spatial light modulation unit 74B is made freely and quickly changeable. In other words, as in the embodiment of fig. 1, the modified example of fig. 9 can also realize an illumination condition having a large variation in the shape, size, and polarization state of the illumination pupil luminance distribution by changing each of the shapes and sizes of the first light intensity distribution and the second light intensity distribution in mutually different polarization states.

Since the modified example of fig. 9 uses the diffractive optical element 71 as a beam splitter, it has an advantage of making an improvement in uniformity of the intensity of light rays incident on the spatial light modulators in the spatial light modulation cells 74A, 74B. This modified example has an advantage that the positions of the beams incident on the spatial light modulators in the spatial light modulation units 74A, 74B are less likely to change, since the angles of the beams immediately after the diffractive optical element 71 do not change even when the position of the beam incident on the diffractive optical element 71 changes.

In the modification example of fig. 9, in the case where a beam having a rectangular cross section is incident on the diffractive optical element 71, the incident beam may be split in the direction of the short side of the rectangular cross section in order to miniaturize the prism 23B and thus miniaturize the spatial light modulation units 74A and 74B. In other words, the incident beam can be split in a plane in which the longitudinal direction of the active area of the spatial light modulator in the spatial light modulation unit 74A, 74B is the normal. In general, in the case where the incident light has a sectional shape in which the length along a first direction in the cross section of the beam incident to the diffractive optical element 71 is smaller than the length along a second direction perpendicular to the first direction, the spatial light modulation units 74A and 74B can be made compact by splitting the incident beam along the first direction.

In the modified example of fig. 9, the diffractive optical element 71 is used to split the incident beam into two beams. However, it is not necessarily limited thereto, and it is also possible to adopt a configuration in which an incident beam is split into two beams by using a prism unit 76 having a pair of prism members 76a and 76b (as shown in fig. 12, for example). The modification example of fig. 12 has a configuration similar to that of the modification example of fig. 9, but differs from the modification example of fig. 9 only in that a prism unit 76 is arranged instead of the diffractive optical element 71 and the condenser lens 72. In fig. 12, elements having the same functionality as the constituent elements shown in fig. 9 are denoted by the same reference symbols as those in fig. 9. Since the modified example shown in fig. 12 uses the prism unit 76 having the pair of prism members 76a and 76b to split the incident beam into two beams, it becomes possible to miniaturize the apparatus.

The prism unit 76 serving as a beam splitter in the modified example of fig. 12 is composed of the following components arranged in the order specified from the light source side (from the left side in the drawing): a first prism member 76a, a plane on the light source side, a concave and V-shaped refractive surface on the mask side (on the right side of the drawing); and a second prism member 76b, a flat surface on the mask side, and a convex and V-shaped refractive surface on the light source side. The concave refractive surface of the first prism member 76a is composed of two planes, and an intersection line (ridge line) therebetween extends in the X direction. The convex refractive surface of the second prism member 76b is formed to be complementary to the concave refractive surface of the first prism member 76 a. Specifically, the convex refracting surface of the second prism member 76b is also composed of two planes, and the intersection line (ridge line) therebetween extends in the X direction. In the modified example of fig. 12, the prism unit 76 as a beam splitter is composed of a pair of prism members 76a and 76b, but it is also possible to construct a beam splitter of at least one prism. Furthermore, it is possible to cover various forms of specific configurations of the optical splitter.

In the modified example of fig. 9 and the modified example of fig. 12, each of the half-wave plates 73A and 73B is provided in the optical path between the condenser lens 72 and the spatial light modulation cells 74A and 74B. However, without being necessarily limited thereto, the half-wave plates 73A and 73B may also be located at another appropriate position in the optical path of the first beam and another appropriate position in the optical path of the second beam of the two beams split by the diffractive optical element 71 or by the prism unit 76.

In the modified example of fig. 9 and the modified example of fig. 12, a half-wave plate 73A rotatable about a predetermined axis is provided in the optical path of the first beam, and a half-wave plate 73B rotatable about a predetermined axis is provided in the optical path of the second beam. However, it is not necessarily limited thereto, and it is also possible to adopt a configuration in which a half-wave plate is provided in at least one optical path so as to be rotatable about a predetermined axis or fixed, or a configuration in which a polarizer or an optical rotator other than a half-wave plate is provided in at least one optical path so as to be rotatable about a predetermined axis or fixed.

The half-wave plate (generally a polarizer or optical rotator) may be arranged to be detachable from the optical path so that it can be retracted from the optical path when not required, which may extend the lifetime of the half-wave plate. Similarly, the half-wave plate (generally a polarizer or optical rotator) may be arranged to be replaceable with a glass substrate having the same path length, which may also extend the lifetime of the half-wave plate.

When a quarter-wave plate rotatable about a predetermined axis is arranged in addition to the half-wave plate, the elliptically polarized light can be controlled to be the desired linearly polarized light. A depolarizer (depolarizer) can be used in addition to or instead of a half-wave plate, whereby light in a desired unpolarized state can be obtained. For example, it is also possible to insert a plane parallel plate of a desired thickness in one optical path so as to provide a path length difference between the first beam and the second beam that is not less than the temporal coherence length as described above, whereby the beam passing through the same area on the illumination pupil can be depolarized (depolarized). Further, speckle may be reduced by about (1/2) when an optical path length difference of no less than the temporal coherence length is provided between the first and second beams.

Since the illumination optical apparatus according to the embodiment and the plurality of modified examples uses an optical unit (spatial light modulation unit) having a pair of spatial light modulators in which the postures of mirror elements are individually changed, it is feasible to freely and quickly change an illumination pupil luminance distribution composed of a first light intensity distribution in a first polarization state formed on an illumination pupil by the action of the first spatial light modulator and a second light intensity distribution in a second polarization state formed on the illumination pupil by the action of the second spatial light modulator. In other words, by changing each of the shapes and sizes of the first light intensity distribution and the second light intensity distribution in mutually different polarization states, it is possible to realize an illumination condition having a large variation in the shape, size, and polarization state of the illumination pupil luminance distribution.

In this way, the illumination optical apparatus according to the embodiment and the plurality of modified examples can realize illumination conditions having large variations in the shape, size, and polarization state of the illumination pupil luminance distribution. Further, the exposure apparatus according to the embodiment and the modified examples are capable of performing good exposure under an appropriate illumination condition achieved according to the pattern characteristics of the mask M using an illumination optical apparatus that can achieve an illumination condition with a large variation, and thus manufacturing a good device.

In the above-described embodiment and each of the modification examples, the apparatus may also be configured as follows: the illumination pupil luminance distribution is measured using a pupil luminance distribution measuring device during the formation of the illumination pupil luminance distribution by means of the spatial light modulation unit, and each spatial light modulator in the spatial light modulation unit is controlled in accordance with the measurement result. Such techniques are disclosed, for example, in Japanese patent laid-open application No. 2006-54328, as well as Japanese patent laid-open application No. 2003-22967 and its corresponding U.S. patent laid-open application No. 2003/0038225.

In the foregoing embodiment, the mask may be replaced with a variable patterning device that forms a predetermined pattern on the basis of predetermined electronic data. The use of such a variable patterning device minimizes the impact on synchronization accuracy, even when the pattern surface is vertical. A variable patterning device applicable herein may be, for example, a DMD (digital micromirror device) including a plurality of reflective elements driven based on predetermined electronic data. An exposure apparatus using a DMD is disclosed in, for example, japanese patent laid-open application No. 2004-304135 and international publication No. WO2006/080285 and its corresponding U.S. patent laid-open application No. 2007/0296936. In addition to the non-emissive type of reflective spatial light modulator like the DMD, it is also possible to use a transmissive spatial light modulator or to use a self-emissive (self-emission) type of image display device. The variable patterning device may also be used where the pattern surface is horizontal.

The exposure apparatus according to the foregoing embodiments is manufactured by assembling various subsystems containing their respective components as set forth in the scope of claims in the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. To ensure these different accuracies, the following adjustments may be made before and after assembly: adjustments for achieving optical accuracy of various optical systems; adjustments to achieve mechanical accuracy of various mechanical systems; for achieving adjustment of electrical accuracy of various electrical systems. The step of assembling the various subsystems into the exposure apparatus includes mechanical connections between the various subsystems, wire connections of electric circuits, pipe connections of pneumatic lines, and the like. Not surprisingly, there is an assembly step of the individual subsystems prior to the step of assembling the various subsystems into the exposure apparatus. After the step of assembling the various subsystems into the exposure apparatus is completed, overall adjustment is performed to ensure various accuracies of the entire exposure apparatus. Ideally, the manufacture of the exposure apparatus is performed in a clean room in which temperature, cleanliness, and the like are controlled.

A device manufacturing method using the exposure apparatus of the above-described embodiment will be described below. Fig. 13 is a flowchart showing the manufacturing steps of the semiconductor device. As shown in fig. 13, the manufacturing steps of the semiconductor device include: depositing a metal film on the wafer W to become a substrate for a semiconductor device (step S40); and applying a photoresist as a photosensitive substrate to the deposited metal film (step S42). The subsequent steps include transferring the pattern formed on the mask (reticle) M into each shot region on the wafer W using the projection exposure apparatus of the above-described embodiment (step S44: exposure step); and performing development of the wafer W after completion of the transfer, that is, development of the resist to which the pattern has been transferred (step S46: developing step). The next step is to process the surface of the wafer W by etching or the like using the resist pattern made on the surface of the wafer W in step S46 as a mask (step S48: processing step).

The resist pattern herein is a photoresist layer in which projections and depressions are formed in a shape corresponding to the pattern transferred by the projection exposure apparatus of the above-described embodiment, and the depressions penetrate the photoresist layer. In step S48, the surface of the wafer W is processed through this resist pattern. The processing performed in step S48 includes, for example, at least either of etching the surface of the wafer W or depositing a metal film or the like. In step S44, the projection exposure apparatus of the above embodiment performs transfer of a pattern using the wafer W coated with the photoresist as a photosensitive substrate or plate P.

Fig. 14 is a flow chart showing steps of manufacturing a liquid crystal device (e.g., a liquid crystal display device). As shown in fig. 14, the manufacturing step of the liquid crystal device includes sequentially performing a pattern forming step (step S50), a color filter forming step (step S52), a cell assembling step (step S54), and a module assembling step (step S56).

The pattern forming step of step S50 is to form predetermined patterns (e.g., a circuit pattern and an electrode pattern) on a glass substrate coated with a photoresist as a plate P using the projection exposure apparatus of the above-described embodiment. The pattern forming step includes: an exposure step of transferring a pattern onto the photoresist layer by means of the projection exposure apparatus of the above embodiment; a developing step of developing the plate P after the transfer of the pattern, that is, developing the photoresist layer on the glass substrate to produce a photoresist layer having a shape corresponding to the pattern; and a treatment step of treating the surface of the glass substrate through the developed photoresist layer.

The color filter forming step of step S52 is to form a color filter in the following configuration: a large number of groups of three dots corresponding to R (red), G (green), and B (blue) form an array configuration in a matrix pattern, or a plurality of groups of R, G and B of three kinds of band filters form an array configuration in the horizontal scanning direction.

The cartridge assembling step of step S54 is to assemble a liquid crystal panel (liquid crystal cell) using the glass substrate having the predetermined pattern thereon in step S50 and the color filter formed in step S52. Specifically, a liquid crystal panel is formed, for example, by pouring liquid crystal between a glass substrate and a color filter. The module assembling step of step S56 attaches various components (e.g., a circuit and a backlight element for display operation of this liquid crystal panel) to the liquid crystal panel assembled in step S54.

The present invention is not limited to application to exposure apparatuses for manufacturing semiconductor devices, but can also be widely applied to, for example, exposure apparatuses for display devices (for example, liquid crystal display devices or plasma displays formed with rectangular glass plates), and exposure apparatuses for manufacturing various devices (for example, imaging devices (CCDs or the like), micromachines, thin film magnetic heads, and DNA chips). Further, the present invention is also applicable to an exposure step (exposure apparatus) in manufacturing a mask (photomask, reticle, or the like) having mask patterns of various devices by photolithography.

The foregoing examples use ArF excimer laser light (wavelength: 193nm) or KrF excimer laser light (wavelength: 248nm) as the exposure light, but the exposure light is not necessarily limited to these lights: the invention is also applicable to any other suitable laser light source, for example, an F2 laser light source supplying laser light with a wavelength of 157 nm.

In the foregoing embodiment, it is also possible to apply a technique of filling the inside of an optical path between the projection optical system and the photosensitive substrate with a medium (generally, a liquid) having a refractive index of more than 1.1, which is a so-called liquid immersion (immersion) method. In this case, it is possible to adopt one of the following techniques as a technique for filling the inside of an optical path between the projection optical system and the photosensitive substrate with a liquid: techniques for partially filling an optical path with a liquid, as disclosed in international publication WO 99/49504; a technique of moving a stage for holding a substrate to be exposed in a bath (bath), as disclosed in japanese patent laid-open application No. 6-124873; a technique of forming a liquid pool of a predetermined depth on a stage and holding a substrate therein, as disclosed in japanese patent laid-open application No. 10-303114; and so on.

The foregoing embodiments are applications of the present invention to an illumination optical apparatus for illuminating a mask in an exposure apparatus, but is not necessarily limited thereto, and the present invention may also be applied to any general illumination optical apparatus for illuminating an illumination target surface different from the mask.

It should be noted that the above-explained embodiments are described only for easy understanding of the present invention and not for limiting the present invention. Therefore, each element disclosed in the embodiments is intended to include all design changes and equivalents falling within the technical scope of the present invention. Each of the constituent elements and others in the above-described embodiments may be applied in any combination or the like.

Claims (24)

1. An illumination optical apparatus that illuminates illumination light to a mask on which a pattern is formed, characterized by comprising:

a spatial light modulator, comprising: a plurality of reflection surfaces arranged along a predetermined surface and provided in an optical path of the illumination light, the plurality of reflection surfaces being individually controlled to distribute the illumination light in an illumination pupil of the illumination optical apparatus to a region away from an optical axis of the illumination optical apparatus;

a polarization unit disposed in an optical path of the illumination light, for converting a polarization state of the illumination light;

a fly-eye lens disposed in an optical path of the illumination light between the spatial light modulator and the illumination pupil;

a 1 st reflective surface that reflects incident illumination light toward the spatial light modulator; and

a 2 nd reflecting surface that reflects the illumination light incident via the spatial light modulator,

the 1 st reflecting surface and the 2 nd reflecting surface are different surfaces from the plurality of reflecting surfaces,

wherein the fly-eye lens is arranged in the optical path in such a manner that a rear-side focal position of the fly-eye lens coincides with the illumination pupil,

the polarization unit converts the polarization state of the illumination light so that the illumination light incident to the polarization unit in the polarization state having linearly polarized light whose polarization direction is a predetermined direction as a main component becomes a circularly polarized state in the illumination pupil,

the 1 st reflective surface, the spatial light modulator, and the 2 nd reflective surface are configured to: illumination light incident on the 1 st reflective surface along a traveling direction is reflected by the 2 nd reflective surface toward a direction parallel to the traveling direction after passing through the spatial light modulator.

2. The illumination optical apparatus according to claim 1,

the spatial light modulator is: controlling the plurality of reflective surfaces in a manner that the illumination light distribution in the illumination pupil is a multipole-shaped region or an annular-shaped region.

3. The illumination optical apparatus according to claim 2,

the spatial light modulator is: the plurality of reflection surfaces are controlled in such a manner that the illumination light in the illumination pupil is distributed in two regions spaced apart in a 1 st direction with the optical axis as a center and in two regions spaced apart in a 2 nd direction perpendicular to the 1 st direction.

4. The illumination optical apparatus according to claim 1,

comprises two polarization units of a 1 st polarization unit and a 2 nd polarization unit,

comprising two spatial light modulators, a 1 st spatial light modulator and a 2 nd spatial light modulator,

the 1 st polarization unit has a polarization state in which a 1 st light flux incident on a reflection surface of the 1 st spatial light modulator among the illumination light from the beam splitter becomes a 1 st linearly polarized light as a main component, the 2 nd polarization unit has a polarization state in which a 2 nd light flux incident on a reflection surface of the 2 nd spatial light modulator among the illumination light from the beam splitter becomes a 2 nd linearly polarized light as a main component,

the 1 st spatial light modulator distributes the 1 st light beam from the 1 st polarization unit to a 1 st area of the illumination pupil, and the 2 nd spatial light modulator distributes the 2 nd light beam from the 2 nd polarization unit to a 2 nd area of the illumination pupil different from the 1 st area.

5. The illumination optical apparatus according to claim 4,

the 1 st light beam is reflected with a reflective surface of the 1 st spatial light modulator and the 2 nd light beam is reflected with a reflective surface of the 2 nd spatial light modulator.

6. The illumination optical apparatus according to claim 4,

the polarization unit is disposed in an optical path of at least one of the 1 st light beam and the 2 nd light beam.

7. The illumination optical apparatus according to claim 6,

the spatial light modulator is: the plurality of reflection surfaces are controlled in such a manner that the illumination light is distributed in a multipole or ring shape on the incident surface of the fly-eye lens.

8. The illumination optical apparatus according to claim 1,

the polarization unit includes a half-wave plate or an optical rotator.

9. The illumination optical apparatus according to claim 1,

the polarization unit is arranged in an optical path of the illumination light in an incident side of the spatial light modulator.

10. An exposure apparatus that exposes a pattern formed on a mask to a substrate, characterized by comprising:

a movable stage supporting the substrate;

the illumination optical apparatus of any one of claims 1 to 9, illuminating the pattern; and

and a projection optical system that forms an image of the pattern illuminated using the illumination optical device on the substrate supported by the stage.

11. The exposure apparatus according to claim 10,

the illumination pupil of the illumination optical apparatus and the entrance pupil of the projection optical system are arranged at positions conjugate to each other.

12. An illumination method of illuminating a mask on which a pattern is formed with illumination light, characterized by comprising:

reflecting the illumination light with a spatial light modulator having a plurality of reflection surfaces arranged along a predetermined surface and individually controllable, the illumination light being distributed on an area on an illumination pupil away from an optical axis via a fly-eye lens;

converting a polarization state of the illumination light by a polarization unit disposed in an optical path of the illumination light;

reflecting the incident illumination light toward the spatial light modulator with a 1 st reflective surface; and

the illumination light incident via the spatial light modulator is reflected by the 2 nd reflecting surface,

the 1 st reflecting surface and the 2 nd reflecting surface are different surfaces from the plurality of reflecting surfaces,

wherein the fly-eye lens is arranged such that a rear-side focal position of the fly-eye lens coincides with the illumination pupil,

the polarization unit converts the polarization state of the illumination light so that the illumination light incident to the polarization unit in the polarization state having linearly polarized light whose polarization direction is a predetermined direction as a main component becomes a circularly polarized state in the illumination pupil,

the 1 st reflective surface, the spatial light modulator, and the 2 nd reflective surface are: so that illumination light incident on the 1 st reflecting surface in the traveling direction is reflected by the 2 nd reflecting surface toward a direction parallel to the traveling direction after passing through the spatial light modulator.

13. The lighting method according to claim 12,

the plurality of reflective surfaces are: the illumination light is controlled so as to be distributed in a multipole-shaped region or an annular-shaped region in the illumination pupil.

14. The lighting method according to claim 13,

the plurality of reflective surfaces are: the illumination pupil is controlled so that the illumination light is distributed in two regions spaced apart in a 1 st direction with the optical axis as a center and in two regions spaced apart in a 2 nd direction perpendicular to the 1 st direction.

15. The lighting method according to claim 12,

comprises two polarization units of a 1 st polarization unit and a 2 nd polarization unit,

comprising two spatial light modulators, a 1 st spatial light modulator and a 2 nd spatial light modulator,

the 1 st polarization unit has a polarization state in which a 1 st light flux incident on a reflection surface of the 1 st spatial light modulator among the illumination light from the beam splitter becomes a 1 st linearly polarized light as a main component, the 2 nd polarization unit has a polarization state in which a 2 nd light flux incident on a reflection surface of the 2 nd spatial light modulator among the illumination light from the beam splitter becomes a 2 nd linearly polarized light as a main component,

the 1 st spatial light modulator distributes the 1 st light beam from the 1 st polarization unit to a 1 st area of the illumination pupil, and the 2 nd spatial light modulator distributes the 2 nd light beam from the 2 nd polarization unit to a 2 nd area of the illumination pupil different from the 1 st area.

16. The lighting method according to claim 15,

the 1 st light beam is reflected with a reflective surface of the 1 st spatial light modulator and the 2 nd light beam is reflected with a reflective surface of the 2 nd spatial light modulator.

17. The lighting method according to claim 15,

the polarization unit is disposed in an optical path of at least one of the 1 st light beam and the 2 nd light beam.

18. The lighting method according to claim 17,

the plurality of reflective surfaces are: the control is performed so that the illumination light is distributed in a multipole or ring shape on the incident surface of the fly-eye lens.

19. The lighting method according to claim 12,

the polarization unit includes a half-wave plate or an optical rotator.

20. The lighting method according to claim 12,

the polarization unit is arranged in an optical path of the illumination light in an incident side of the spatial light modulator.

21. An exposure method of exposing a pattern formed on a mask to a substrate, the exposure method characterized by comprising:

supporting the substrate with a movable stage;

illuminating the pattern with illumination light using the illumination method of any one of claims 12 to 20; and

an image of the pattern illuminated with the illumination light is formed on the substrate supported by the stage via a projection optical system.

22. The exposure method according to claim 21,

the illumination pupil and the entrance pupil of the projection optical system are arranged at conjugate positions with each other.

23. A device manufacturing method characterized by comprising:

exposing a pattern formed on a mask onto a substrate using the exposure apparatus according to claim 10; and

developing the substrate with the pattern exposed.

24. A device manufacturing method characterized by comprising:

exposing a pattern formed on a mask onto a substrate using the exposure method according to claim 21; and

developing the substrate with the pattern exposed.