WO2009150871A1

WO2009150871A1 - Exposure apparatus and device manufacturing method

Info

Publication number: WO2009150871A1
Application number: PCT/JP2009/053632
Authority: WO
Inventors: 修谷津
Original assignee: 株式会社ニコン
Priority date: 2008-06-12
Filing date: 2009-02-27
Publication date: 2009-12-17

Abstract

The influence of uneven pupil intensity distribution is reduced. An exposure apparatus for illuminating a pattern by using plural pulsed light beams (IL) from a light source apparatus for supplying pulsed light, and exposing a substrate to the plural pulsed light beams incident through the pattern is equipped with plural optical elements (3) which are two-dimensionally arranged and individually controlled. The exposure apparatus is provided with a spatial light modulator (13) for performing spatial light modulation on incident light and emitting the resultant light, a pupil intensity distribution forming optical system (14) for forming a pupil intensity distribution on a predetermined surface on the basis of the light incident through the spatial light modulator (13), and an optical element driving unit (4, 31) for individually controlling and driving the states of the plural optical elements (3). The optical element driving unit (4, 31) changes the states of the plural optical elements (3) during light emission of a minimum number of pulses of the plural pulsed light beams to which respective points of a region to be exposed on a substrate (W) are exposed.

Description

Exposure apparatus and device manufacturing method

The present invention relates to a technique for illuminating an irradiated surface using a plurality of optical elements each capable of spatially modulating light, and exposing a pattern placed on the irradiated surface onto a substrate.

For example, in a lithography process for manufacturing a device (electronic device, microdevice) such as a semiconductor element or a liquid crystal display element, a pattern of a reticle (or photomask) is transferred to a wafer (or glass plate, etc.) via a projection optical system. In order to perform the transfer, an exposure apparatus such as a batch exposure type projection exposure apparatus such as a stepper or a scanning exposure type projection exposure apparatus such as a scanning stepper is used. In these exposure apparatuses, the exposure wavelength has been shortened to increase the resolution, and recently, excimer laser light such as KrF (wavelength 248 nm) or ArF (wavelength 193 nm) is used as exposure light. Further, the use of an F ₂ laser (wavelength 157 nm) or the like as exposure light is also being studied.

In recent illumination optical systems of exposure apparatuses, a reticle pattern (or mask pattern or the like) can be illuminated with an optimal light intensity distribution (intensity distribution) in order to accurately transfer a fine pattern onto a wafer. It is essential. For example, modified illumination for forming an annular or multipolar (for example, dipole or quadrupole) light intensity distribution on the illumination pupil plane of the illumination optical system is performed, and the depth of focus and resolution of the projection optical system are reduced. Improvement technology is attracting attention. As one of the techniques, for example, in order to convert a light beam from a light source into a light beam having a ring-shaped or multipolar light intensity distribution on the illumination pupil plane of the illumination optical system, it is arranged in a two-dimensional array. A spatial light modulator having a large number of minute mirror elements is provided, and predetermined light is applied to the illumination pupil plane of the illumination optical system or a plane conjugate with the illumination pupil plane by changing the tilt angle and tilt direction of each mirror element. An exposure apparatus that forms an intensity distribution has been proposed (see, for example, Patent Document 1).

JP 2002-353105 A

By the way, in the above-described exposure apparatus, on the illumination pupil plane of the illumination optical system or a plane conjugate with the illumination pupil plane using a spatial light modulator having a large number of minute mirror elements arranged in a two-dimensional array. A predetermined light intensity distribution (hereinafter referred to as “pupil intensity distribution”) is formed, and the laser light from the laser light source is wavefront-divided by a plurality of minute mirror elements of the spatial light modulator. However, since the number of wavefront divisions by a spatial light modulator of a type including a plurality of micromirror elements is smaller than the number of wavefront divisions by a typical diffractive optical element, there is a problem that unevenness of pupil intensity distribution occurs.

The present invention has been made in view of the above-described problems, and an object thereof is to reduce the influence of unevenness of pupil intensity distribution formed on an illumination pupil plane of an illumination optical system in an exposure apparatus.

An exposure apparatus according to the present invention is an exposure apparatus that illuminates a pattern using a plurality of pulse lights from a light source device that supplies pulse light, and exposes a substrate with the plurality of pulse lights that pass through the pattern. A spatial light modulator having a plurality of optical elements that are dimensionally arranged and individually controlled, and that emits light by applying spatial light modulation to incident light; and the light that passes through the spatial light modulator A pupil intensity distribution forming optical system that forms a pupil intensity distribution on a predetermined plane based on the optical element driving unit that individually controls and drives the states of the plurality of optical elements. Then, the optical element driving unit changes the state of the plurality of optical elements while the minimum number of pulses of the plurality of pulsed light exposed to each point of the exposed region on the substrate is emitted. In other words, for example, the optical element driving unit performs every pulse number smaller than the minimum pulse number (required pulse number) that is the number of pulsed light necessary for exposing each point of the exposed area on the substrate. , Changing the states of the plurality of optical elements.

A device manufacturing method according to the present invention includes an exposure step of exposing the pattern onto the substrate using the exposure apparatus according to the present invention, developing the substrate onto which the pattern has been transferred, and a mask having a shape corresponding to the pattern A development step of forming a layer on the surface of the substrate; and a processing step of processing the surface of the substrate through the mask layer.

According to the present invention, the state of the plurality of optical elements of the spatial light modulator is changed for each number of pulses smaller than the minimum number of pulses, which is the number of pulsed light necessary for exposing a predetermined point in the exposed area. is doing. In other words, the predetermined point includes the pulse light when the plurality of optical elements of the spatial light modulator are in the first state, and the pulse when the second state is different from the first state. The light will reach at least. For this reason, in the exposure apparatus and device manufacturing method of the present invention, the pupil intensity distribution is averaged over time to reduce (reduce) the influence of the unevenness of the pupil intensity distribution, and exposure can be performed under stable and favorable illumination conditions. It can be carried out.

It is a figure which shows schematic structure of the exposure apparatus of an example of embodiment of this invention. (A) is an enlarged perspective view showing a part of the spatial light modulator 13 of FIG. 1, and (B) is an enlarged perspective view showing a drive mechanism of the mirror element 3 of FIG. (A) is a figure which shows the secondary light source at the time of bipolar illumination, (B) is a figure which shows the light intensity distribution of the cross section in the predetermined one direction of the secondary light source of FIG. 3 (A). (A) is a diagram showing the state of the tilt angle of the mirror element of the spatial light modulator 13 in FIG. 1 during dipole illumination, and (B) is a light flux from the mirror element having a tilt angle distribution different from that in FIG. 4 (A). The figure which shows the state which performs dipole illumination, (C) is a figure which shows the state which performs dipole illumination with the light beam from the mirror element of inclination-angle distribution different from FIG. 4 (A) and FIG. 4 (B). (A) is a diagram showing the light intensity distribution on the illumination pupil plane when the mirror element of the spatial light modulator 13 of FIG. 1 is in the state shown in FIG. 4 (A), and (B) is the two in FIG. 5 (A). The figure which shows the light intensity distribution of the cross section in the predetermined one direction of a next light source, (C) is the light in the illumination pupil plane in case the mirror element of the spatial light modulator 13 of FIG. 1 is in the state shown in FIG.4 (B). FIG. 5D is a diagram showing an intensity distribution, FIG. 5D is a diagram showing a light intensity distribution of a cross section in a predetermined direction of the secondary light source of FIG. 5C, and FIG. The figure which shows the light intensity distribution in the illumination pupil plane in the state shown in FIG.4 (C), (F) is a figure which shows the light intensity distribution of the cross section in the predetermined one direction of the secondary light source of FIG.5 (E). It is. It is a figure of the principal part which shows the illumination area | region 26 of the reticle R of FIG. (A) is a diagram showing another secondary light source during dipole illumination, (B) is a diagram showing a secondary light source during normal illumination, (C) is a diagram showing a secondary light source during annular illumination, D) is a diagram showing a secondary light source during quadrupole illumination. (A) is a figure which shows the structural example of the illumination optical system using the rod type | mold integrator 50, (B) is a figure which shows the principal part of the structural example of the illumination optical system which does not use a prism. It is a flowchart which shows an example of the process at the time of manufacturing a device using the exposure apparatus of embodiment.

Explanation of symbols

ILS ... illumination optical system, R ... reticle, PL ... projection optical system W ... wafer, 3 ... mirror element, 7 ... light source, 9 ... 1/2 wavelength plate 10 DESCRIPTION OF SYMBOLS ... Depolarizer, 12 ... Prism, 13 ... Spatial light modulator 14 ... Relay optical system, 15 ... Fly eye lens, 30 ... Main control system 31 ... Modulation control part, 50 ... Rod type integrator, 100 ... Exposure apparatus

Hereinafter, an example of a preferred embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a view showing a schematic configuration of a scanning exposure type exposure apparatus (projection exposure apparatus) 100 comprising a scanning stepper according to this embodiment. In FIG. 1, an exposure apparatus 100 illuminates a pattern surface (illuminated surface) of a reticle R (mask) with exposure illumination light (exposure light) IL from an exposure light source 7 that emits pulsed light. ILS, reticle stage RST for positioning and moving reticle R, projection optical system PL for projecting an image of the pattern of reticle R onto wafer W (photosensitive substrate) arranged on the exposure surface, It includes a wafer stage WST that performs positioning and movement, a main control system 30 that includes a computer that controls the overall operation of the apparatus, various control systems, and the like. In FIG. 1, the Z axis is set perpendicular to the guide surface (not shown) of wafer stage WST, the Y axis is perpendicular to the paper surface of FIG. 1 in the direction parallel to the paper surface of FIG. Set the X axis in each direction. In the present embodiment, the reticle R and the wafer W are scanned in the Y direction (scanning direction) during exposure.

As the light source 7 in FIG. 1, an ArF excimer laser light source is used that emits a pulse of approximately linearly polarized laser light having a wavelength of 193 nm and a pulse width of about 50 ns at a frequency of about 4 to 6 kHz. As the light source 7, a KrF excimer laser light source that supplies pulsed light with a wavelength of 248 nm, an F ₂ laser light source that supplies pulsed light with a wavelength of 157 nm, or a light-emitting diode that is pulsed can be used. Further, as the light source 7, a solid-state pulse laser light source that generates harmonics of laser light output from a YAG laser or a semiconductor laser, or a solid-state pulse that generates harmonics of light obtained by amplifying the semiconductor laser light with a fiber amplifier. Laser light sources can also be used. The solid-state pulse laser light source can emit laser light with a wavelength of 193 nm (various other wavelengths are possible) and a pulse width of about 1 ns at a frequency of about 1 to 2 MHz.

In the present embodiment, the power source control unit 32 is connected to the light source 7. Then, the main control system 30 of the exposure apparatus 100 supplies a light emission trigger pulse TP instructing the pulse light emission timing and the light amount (pulse energy) to the power supply control unit 32. In synchronization with the light emission trigger pulse TP, the power supply control unit 32 causes the light source 7 to emit pulses at the instructed timing and light quantity.

Linearly polarized illumination light IL made up of pulsed laser light having a rectangular and substantially parallel light flux emitted from the light source 7 is incident on a beam expander 8 having a pair of concave and convex lenses and enlarged. . The illumination light IL emitted from the beam expander 8 is a half-wave plate 9 (polarization control member) for rotating the polarization direction of the illumination light IL in a predetermined direction in the illumination optical system ILS having the optical axis AXI. The illumination light IL passes through a polarization optical system including a depolarizer 10 that converts the illumination light IL into random polarization (non-polarization). The depolarizer 10 includes a wedge-shaped first prism 10a made of a birefringent material (for example, quartz) and a second prism 10b made of a material (for example, quartz) that has a complementary shape and does not have birefringence. It is provided so as to be detachable with respect to the illumination optical path. When the depolarizer 10 is inserted into the illumination optical path, the illumination light IL that has passed through the depolarizer 10 is unpolarized.

The half-wave plate 9 is provided so as to be rotatable around the optical axis AXI. By controlling the orientation of the half-wave plate 9 around the optical axis AXI, the half-wave plate 9 is interposed via the half-wave plate 9. It is possible to control the polarization direction of the illumination light IL, and hence the polarization direction of light reaching the irradiated surface or the exposed surface. The rotation of the half-wave plate 9 around the optical axis AXI is controlled by the drive unit 33 in accordance with a command from the main control system 30.

Here, the half-wave plate 9 and the depolarizer 10 can be regarded as a polarization control unit. The detailed configuration and operation of the polarization control unit including the half-wave plate 9 and the depolarizer 10 are disclosed in US Patent Publication No. 2006/0055834.

The illumination light IL that has passed through the polarization control unit is reflected in the + Y direction by the mirror 11 for bending the optical path, and then, along the optical axis AXI, a prism 12 having an entrance surface 12d and an exit surface 12e perpendicular to the optical axis AXI. Is incident on the incident surface 12d. The prism 12 is made of an optical material such as fluorite (CaF ₂ ) or quartz that transmits the illumination light IL. In addition, as an example, the prism 12 has a first reflecting surface 12a that intersects the incident surface 12d clockwise at about 60 ° about an axis parallel to the X axis, and the first reflecting surface 12a and the XZ plane. The second reflection surface 12b is substantially symmetric with respect to the parallel surface, and the transmission surface 12c is parallel to the XY plane and orthogonal to the incident surface 12d (exit surface 12e).

Further, in the vicinity of the prism 12, a space having a large number of mirror elements 3 that are minute mirrors arranged in a two-dimensional array and each having a variable tilt angle, and a drive unit 4 that drives these mirror elements 3. An optical modulator 13 is installed. A large number of mirror elements 3 of the spatial light modulator 13 are disposed substantially parallel to and close to the transmission surface 12c as a whole. In addition, each mirror element 3 can be controlled almost continuously within a predetermined variable range with respect to the angle of inclination of the reflecting surface around an axis parallel to the X axis and the Y axis (two axes orthogonal to each other). As an example, at the center within the variable range, the reflecting surface of each mirror element 3 is substantially parallel to the transmitting surface 12c.

FIG. 2A is an enlarged perspective view showing a part of the spatial light modulator 13. In FIG. 2A, the spatial light modulator 13 determines the angles of a large number of mirror elements 3 arranged so as to be in close contact with each other at a constant pitch in the X direction and the Y direction, and the reflection surfaces of the large number of mirror elements 3. The drive part 4 controlled individually is included. The number of arrangements of the mirror elements 3 in the X direction and the Y direction is, for example, thousands.

As shown in FIG. 2B, as an example, the drive mechanism of the mirror element 3 includes a support substrate 38, a support member 36 that is formed on the support substrate 38 and supports the mirror element 3 in a swingable manner. There are provided four electrodes 39 formed on the support substrate 38 so as to surround the support member 36. In this configuration example, the mirror element 3 is controlled by controlling the potential difference between the four electrodes 39 and the back surface of the mirror element 3 to control the electrostatic force acting between the electrode 39 and the back surface of the mirror element 3. Can be swung and tilted. Thereby, the inclination angle around two orthogonal axes of the reflection surface of the mirror element 3 supported by the support member 36 can be continuously controlled within a predetermined variable range. A more detailed configuration of the spatial light modulator 13 is disclosed in, for example, Japanese Patent Application Laid-Open No. 2002-353105.

Note that the drive mechanism of the mirror element 3 is not limited to the configuration of the present embodiment, and any other mechanism can be used. Furthermore, although the mirror element 3 is a substantially square plane mirror, the shape thereof may be an arbitrary shape such as a rectangle. However, from the viewpoint of light utilization efficiency, a shape that can be arranged without a gap is preferable. Moreover, it is preferable that the interval between the adjacent mirror elements 3 is minimized. At present, the shape of the mirror element 3 is, for example, about 10 μm square to several tens μm square. In order to reduce the influence of diffracted light from the peripheral edge of the mirror element 3, the mirror element 3 is made as much as possible. Small is preferable. Moreover, in order to enable fine changes in illumination conditions, the mirror element 3 is preferably as small as possible. Furthermore, although the reflecting surface of the mirror element 3 is a flat surface, it can be a concave reflecting surface or a convex reflecting surface.

As the spatial light modulator 13, for example, Japanese Patent Laid-Open No. 10-503300 and European Patent Publication No. 779530 corresponding thereto, Japanese Patent Application Laid-Open No. 2004-78136, and US Patent No. 6 corresponding thereto. , 900,915, JP-T 2006-524349, and US Pat. No. 7,095,546 corresponding thereto, and JP-A-2006-113437. it can. When these spatial light modulators are used in the illumination optical system ILS, the respective light beams through the individual reflecting surfaces of the spatial light modulator are pupil intensity distribution forming optical systems (relay optical system 14) at a predetermined angle. , And a predetermined light intensity distribution according to control signals to a plurality of mirror elements (reflection elements) can be formed on the illumination pupil plane.

Now, returning to FIG. 1, the main control system 30 supplies the modulation control unit 31 with information on illumination conditions and information on the emission timing of the illumination light IL. In the modulation control unit 31, each time the illumination light IL is emitted by a plurality of pulses smaller than the minimum number of pulses, the illumination condition is maintained, and the rotation around the two axes of the many mirror elements 3 is performed. The drive unit 4 is controlled so as to sequentially switch the distribution of the inclination angles to a plurality of states periodically (details will be described later). Here, the spatial light modulator 13 forms a desired pupil intensity distribution in the far field.

In this case, the illumination light IL incident on the incident surface 12d of the prism 12 in parallel or substantially parallel to the optical axis AXI is totally reflected by the first reflecting surface 12a, and then passes through the transmitting surface 12c to be transmitted to the spatial light modulator 13. Are incident on a number of mirror elements 3. The illumination light IL reflected by the large number of mirror elements 3 enters the transmission surface 12c again, is totally reflected by the second reflection surface 12b, and is emitted from the emission surface 12e. Accordingly, the angle of the first reflecting surface 12a with respect to the incident surface 12d is such that the light beam incident perpendicularly to the incident surface 12d is totally reflected by the first reflecting surface 12a and the light beam totally reflected by the first reflecting surface 12a is the transmitting surface. It may be in a range that transmits 12c. At this time, if the reflection surface of any mirror element 3 is substantially parallel to the transmission surface 12c, the illumination light IL reflected by the mirror element 3 is transmitted through the transmission surface 12c and is reflected by the second reflection surface 12b. After being totally reflected, the light is emitted almost parallel to the optical axis AXI through the emission surface 12e. Therefore, by controlling the inclination angle of each mirror element 3 around the two axes, the angles of the two directions orthogonal to the optical axis AXI of the illumination light IL reflected from the mirror element 3 and emitted from the prism 12 are controlled. it can. Controlling the angle of the illumination light IL with respect to the optical axis AXI is spatial modulation by each mirror element 3 of the present embodiment, and the angle of the illumination light IL from each mirror element 3 with respect to the optical axis AXI is controlled. The distribution corresponds to one illumination control pattern.

Thus, although the reflection surfaces 12a and 12b of the prism 12 use total reflection, a reflection film may be formed on the reflection surfaces 12a and 12b, and the illumination light IL may be reflected by the reflection film. The illumination light IL emitted from the prism 12 enters the fly-eye lens 15 (optical integrator) via the relay optical system 14. Here, the reflecting surface of each mirror element 3 is disposed substantially at the front focal plane of the relay optical system 14, and the incident surface of the fly-eye lens 15 is disposed substantially at the rear focal plane of the relay optical system 14. It is not limited to this arrangement.

FIG. 4A shows an optical system from the prism 12 to the fly-eye lens 15 in FIG. In FIG. 4A, when the inclination angle of the light beam incident on the relay optical system 14 with respect to the optical axis AXI is θ and the rear focal length of the relay optical system 14 is f, for example, on the incident surface of the fly-eye lens 15. The height h from the optical axis AXI at the position where the light beam is condensed is as shown in the following equation (1).
h = f · sinθ (1)

Accordingly, in FIG. 1, the relay optical system 14 determines the illumination light IL reflected by each mirror element 3 on the incident surface of the fly-eye lens 15 that is determined in accordance with two orthogonal angles with respect to the optical axis AXI. An angle / position conversion function for condensing light at positions in the X and Z directions is provided.

In other words, the illumination light IL incident on the spatial light modulator 13 via the prism 12 is divided with the mirror element 3 as a unit, and is deflected at a predetermined angle in a predetermined direction according to the inclination direction and the inclination angle of each mirror element 3 ( Reflected). The reflected light from each mirror element 3 can be condensed by the prism 12 and the relay optical system 14 at an arbitrary position on the incident surface of the fly-eye lens 15 according to the direction and angle.

The illumination light IL incident on the fly-eye lens 15 is two-dimensionally divided by a large number of lens elements, and a light source is formed on the rear focal plane of each lens element. In this way, the pupil plane (illumination pupil plane 22) of the illumination optical system ILS, which is the rear focal plane of the fly-eye lens 15, has substantially the same intensity distribution as the illumination area formed by the light flux incident on the fly-eye lens 15. A secondary light source is formed, that is, a secondary light source consisting essentially of a surface light source. In the present embodiment, the light intensity distribution on the incident surface of the fly-eye lens 15 and thus the fly-eye lens are controlled by individually controlling the tilt direction and tilt angle of the reflecting surface of each mirror element 3 of the spatial light modulator 13. It is possible to control the intensity distribution of the secondary light source on the illumination pupil plane 22 at or near the position of the 15 rear focal plane to an almost arbitrary distribution.

For example, in the case of mainly exposing line and space patterns arranged at a pitch close to the resolution limit in the Y direction (or X direction) on the pattern surface (reticle surface) of the reticle R in FIG. The secondary light source on the surface 22 has two

secondary light sources

24A and 24B in the Z direction (corresponding to the Y direction on the reticle surface) in FIG. 3B (or two in the X direction in FIG. 7A). Next

light source

24C, 24D). Similarly, the spatial light modulator 13 converts the secondary light source on the illumination pupil plane 22 into a circular secondary light source 28A for normal illumination in FIG. 7B and an annular illumination secondary light in FIG. 7C. It can be set to an arbitrary intensity distribution such as the secondary light source 28B and the quadrupole secondary light sources 24E to 24H for quadrupole illumination shown in FIG. Further, the spatial light modulator 13 can change the interval between the

secondary light sources

24A and 24B and / or the individual sizes of the

secondary light sources

24A and 24B to arbitrary values in FIG. 3B, for example. It is.

In this embodiment, since the reticle R (mask) arranged on the irradiated surface is Koehler illuminated, the surface on which the secondary light source is formed is conjugate with the aperture stop AS of the projection optical system PL. It can be called the illumination pupil plane 22 of the illumination optical system ILS. Typically, the illuminated surface (the surface on which the reticle R is disposed or the surface on which the wafer W is disposed) is an optical Fourier transform surface with respect to the illumination pupil plane 22. The pupil intensity distribution (pupil luminance distribution) is an intensity distribution (luminance distribution) on the illumination pupil plane 22 of the illumination optical system ILS or a plane conjugate with the illumination pupil plane 22. When the number is large, the global luminance distribution formed on the entrance surface of the fly-eye lens 15 and the global luminance distribution (pupil intensity distribution) of the entire secondary light source show a high correlation. The intensity distribution on the incident surface of the lens 15 and the surface conjugate with the incident surface can also be called a pupil intensity distribution. In place of the fly-eye lens 15, a microlens array or the like can be used.

In FIG. 1, illumination light IL from a secondary light source formed on the illumination pupil plane 22 includes a first relay lens 16, a reticle blind (field stop) 17, a second relay lens 18, an optical path bending mirror 19, and Via the condenser optical system 20, the rectangular illumination area 26 elongated in the X direction on the pattern surface (lower surface) of the reticle R is superimposed and illuminated so as to obtain a uniform illuminance distribution.

The illumination optical system ILS includes the optical members from the beam expander 8 to the condenser optical system 20. Each optical member including the spatial light modulator 13 of the illumination optical system ILS is supported by a frame (not shown).

Further, a two-dimensional CCD type or CMOS type imaging device having a light receiving surface capable of covering the cross section of the illumination light IL so that it can be inserted into and removed from the optical path of the illumination light IL between the mirror 11 and the prism 12 in FIG. Alternatively, a photoelectric sensor 23 composed of a two-dimensional photodiode array or the like is disposed. The photoelectric sensor 23 is fixed to, for example, a slider (not shown) that is movably supported on the frame, and a detection signal from the photoelectric sensor 23 is supplied to the modulation control unit 31. In a state where the photoelectric sensor 23 is installed in the optical path of the illumination light IL, the modulation control unit 31 causes the illumination light IL to emit light and capture a detection signal of each pixel (each light receiving element) of the photoelectric sensor 23. The intensity distribution in the cross section of the light IL, and consequently the intensity ratio of the illumination light IL incident on each mirror element 3 of the spatial light modulator 13 (for example, the intensity when the intensity of the incident light of the central mirror element 3 is 1). It can be measured. Using this intensity ratio, the setting accuracy of the intensity distribution of the secondary light source on the illumination pupil plane 22 can be improved.

The pattern in the illumination area 26 of the reticle R is an exposed area on one shot area of the wafer W coated with a resist (photosensitive material) via a telecentric projection optical system PL on both sides (or one side on the wafer side). 27 is projected at a predetermined projection magnification (for example, 1/4, 1/5, etc.).

The reticle R is attracted and held on the reticle stage RST. The reticle stage RST is movable at a constant speed in the Y direction on a guide surface of a reticle base (not shown), and at least in the X direction, the Y direction, and the Z axis. It is mounted so as to be movable in the direction of rotation. The two-dimensional position of reticle stage RST is measured by a laser interferometer (not shown), and based on this measurement information, main control system 30 determines the position of reticle stage RST via a drive system (not shown) such as a linear motor. And control the speed.

On the other hand, wafer W is sucked and held on wafer stage WST via a wafer holder (not shown), and wafer stage WST moves stepwise in the X and Y directions on a guide surface (not shown) and is constant in Y direction. It can move at speed. The two-dimensional position on the guide surface of wafer stage WST is measured by a laser interferometer (not shown), and based on this measurement information, main control system 30 passes through a drive system (not shown) such as a linear motor. Controls the position and speed of wafer stage WST. In order to perform alignment of the wafer W, an alignment system (not shown) for detecting the position of the alignment mark on the wafer W is also provided.

When the exposure apparatus 100 exposes the wafer W, the main control system 30 selects an illumination condition (for example, the intensity distribution of the secondary light source on the illumination pupil plane 22) according to the pattern of the reticle R, and selects the selected illumination condition. Set in the modulation control unit 31. In response to this, the modulation control unit 31 individually controls the tilt direction and tilt angle of each mirror element 3 of the spatial light modulator 13 to set the intensity distribution of the secondary light source on the illumination pupil plane 22. Subsequently, the wafer W is moved to the scanning start position by the step movement of the wafer stage WST. Thereafter, pulse light emission of the light source 7 is started, and the wafer W is moved to the exposure area via the wafer stage WST in synchronization with the movement of the reticle R in the Y direction with respect to the illumination area 26 via the reticle stage RST. By moving the projection magnification as a speed ratio in a direction corresponding to 27, one shot area of the wafer W is scanned and exposed. In this way, the image of the pattern of the reticle R is exposed to all shot regions on the wafer W by the step-and-scan operation that repeats the step movement of the wafer W and the scanning exposure.

Hereinafter, the operation of the spatial light modulator 13 of FIG. 1 will be described. Specifically, a spatial light modulator is taken by taking, as an example, a case in which two-pole

secondary light sources

24A and 24B separated in the Z direction on the illumination pupil plane 22 are generated and the illumination condition is set to two-pole illumination. An example of 13 operations will be described. FIG. 3A is a diagram showing two-pole

secondary light sources

24A and 24B that are separated in the Z direction on the illumination pupil plane 22, and FIG. 3B is a diagram showing the

secondary light sources

24A and 24B in the Z direction. It is a figure which shows light intensity distribution of a cross section.

4A, 4 </ b> B, and 4 </ b> C are representatively selected from, for example, thousands of mirror elements 3 arranged in the Y direction of the spatial light modulator 13 of FIG. 1. The reflected light from the plurality of mirror elements 3A to 3G is shown. For example, in order to form the two-pole

secondary light sources

24A and 24B shown in FIG. 3, the two corresponding portions of the incident surface of the fly-eye lens 15 shown in FIGS. 4A, 4B, and 4C are almost the same. It is necessary to collect the illumination light IL in the

circular areas

25A and 25B.

First, as shown in FIG. 4A, the inclination angles of the mirror elements 3A to 3G of the spatial light modulator 13 (actually, inclination angles around two axes, the same applies hereinafter) are set, The reflected light is condensed on the two regions 25 </ b> A and 25 </ b> B on the incident surface of the fly-eye lens 15 via the second reflecting surface 12 b of the prism 12 and the relay optical system 14. As a result, two-pole secondary light sources 24A1 and 24B1 are generated in the Z direction shown in FIG. FIG. 5B shows the light intensity distribution in the Z direction of the two-pole secondary light sources 24A1 and 24B1 shown in FIG.

4A, since the inclination angles of the mirrors 3A to 3C are the same, the reflected light from these mirrors 3A to 3C is collected in the region 25A in common. On the other hand, since the tilt angles of the mirrors 3D to 3G are the same and are symmetric to the mirrors 3A to 3C, the reflected light from the mirrors 3D to 3G is collected in a region 25B that is symmetrical to the region 25A in common. As for the other mirror elements 3 in the same row of the spatial light modulator 13 and the tilt angles around the two axes of the mirror elements 3 in the other rows, the reflected light is condensed on one of the

regions

25A and 25B. Is set as follows.

In this embodiment, after irradiating m pulses of illumination light IL smaller than the minimum number of pulses in the state of FIG. 4A, the mirror elements 3A to 3G of the spatial light modulator 13 are irradiated as shown in FIG. 4B. , The region 25B is irradiated with the illumination light IL from the mirror elements 3A to 3C, and the region 25A is irradiated with the illumination light IL from the mirror elements 3D to 3G. In this case, the combination of the mirror elements 3A to 3G that reflect the illumination light IL condensed on the

regions

25A and 25B is different from the state of FIG. As a result, two-pole secondary light sources 24A2 and 24B2 are generated in the Z direction shown in FIG. FIG. 5D shows the light intensity distribution in the Z direction of the two-pole secondary light sources 24A2 and 24B2 shown in FIG.

In this state, after irradiating m pulses of illumination light IL smaller than the minimum number of pulses, the distribution of the inclination angles of the mirror elements 3A to 3G of the spatial light modulator 13 is changed as shown in FIG. Then, the region 25B is irradiated with the illumination light IL from the

mirror elements

3A, 3B, 3F, 3G on both sides, and the region 25A is irradiated with the illumination light IL from the central mirror elements 3C to 3E. Also in this case, the combination of the mirror elements 3A to 3G that reflect the illumination light IL condensed on the

regions

25A and 25B is different from the state shown in FIGS. As a result, two-pole secondary light sources 24A3 and 24B3 are generated in the Z direction shown in FIG. FIG. 5F shows the light intensity distribution in the Z direction of the two-pole secondary light sources 24A3 and 24B3 shown in FIG. In this state, m pulses of illumination light IL smaller than the minimum number of pulses are irradiated.

In this way, each time the irradiation light IL of m pulses smaller than the minimum number of pulses is irradiated, the mirror element 3A that reflects the illumination light IL condensed on the

regions

25A and 25B corresponding to the

secondary light sources

24A and 24B. The distribution of angles (illumination control pattern) of the illumination light IL reflected by the mirror elements 3A to 3G with respect to the optical axis AXI is gradually changed. Then, after using all of the predetermined combinations, the distribution of the inclination angles of the mirror elements 3A to 3G is periodically repeated as shown in FIGS. 4 (A), 4 (B), 4 (C),. To change. At this time, the light intensity distribution formed on the illumination pupil plane 22 changes as shown in FIG. 5 (B), FIG. 5 (D), FIG. 5 (F),.

FIG. 6 shows a state in which the reticle R in FIG. 1 is scanned in the scanning direction SD (here, the −Y direction) with respect to the illumination area 26. In FIG. 6, the width of the illumination area 26 in the Y direction is DY, and the movement amount when an arbitrary point 41 on the pattern surface of the reticle R moves to the position 41A during the pulse emission of the illumination light IL is δY. . At this time, the number of irradiation pulses (number of exposure pulses) N (N is an integer of 2 or more) of the illumination light IL with respect to the point 41 is substantially as shown in the following equation (2). The number N of irradiation pulses is several tens, for example.
N = DY / δY (2)

Also, since the combination of the tilt angle distributions of the mirror elements 3A to 3G of the spatial light modulator 13 of FIG. 4 changes every time the illumination light IL is emitted by m pulses, the tilt angle distribution of the mirror elements 3A to 3G is changed. The number M of the illumination control patterns corresponding to the combination may be a minimum integer of at least N / m or more as shown in the following formula (3).
M = smallest integer greater than N / m (3)

Note that when the illumination control pattern is switched every time the illumination light IL is emitted by one pulse, the number M of the illumination control patterns is at least N.

Since the number of mirror elements 3 in each column of the spatial light modulator 13 in FIG. 1 is actually thousands, the mirror element 3 is temporarily divided into 100 blocks in the X direction and the Y direction, and 100 × 100. Even if the tilt direction and tilt angle of the mirror element 3 are controlled in substantially the same state for each block, the number of distributions of different tilt directions and tilt angles of the mirror element 3 (the number M of illumination control patterns) is approximately 10,000. A huge number of factorials is possible. On the other hand, even if m = 1, since N / m is several tens, the condition of Equation (3) can be satisfied with a margin.

As a result, the spatial light modulator is sequentially applied to any point 41 on the reticle R in FIG. 6 every time the illumination light IL is irradiated with m pulses while the illumination light IL is irradiated with N pulses in total. The secondary light sources 24A1, 24B1 shown in FIGS. 5A and 5B, and FIGS. 5C and 5D using the reflected light from the mirror elements 3 having 13 different combinations of inclination angle distributions. The secondary light sources 24A2 and 24B2 shown in FIG. 5 and the secondary light sources 24A3 and 24B3 shown in FIGS. 5E and 5F are sequentially formed on the illumination pupil plane 22. At this time, the intensity distributions of the secondary light sources 24A1, 24B1, 24A2, 24B2, 24A3, 24B3,... Are non-uniform.

As a result, for example, at an arbitrary point 41 in the illumination area 26 of the reticle R, every time the illumination light IL is irradiated with m pulses, the light intensity distribution of the secondary light source corresponding to the illumination light IL reaching that portion. However, secondary light sources 24A1, 24B1, secondary light sources 24A2, 24B2, secondary light sources 24A3, 24B3,.

Therefore, after N pulses of illumination light IL are irradiated to an arbitrary point 41 on the reticle R, the integrated light intensity distribution of the secondary light sources is the secondary light sources 24A1, 24B1, secondary light sources 24A2, 24B2, and secondary light sources. 24A3, 24B3,..., So that unevenness in the light intensity distribution of the secondary light source is reduced by the temporal averaging effect. Due to this temporal averaging effect, an arbitrary condition on the reticle R is obtained under illumination conditions equivalent to the case of illumination with the

secondary light sources

24A and 24B having the top hat-shaped light intensity distribution shown in FIG. This point 41 is illuminated.

Here, information on the combination of the tilt angle distributions of the mirror elements 3A to 3G of the spatial light modulator 13 is stored in the modulation control unit 31 in the form of, for example, a look-up table for each illumination condition. Therefore, when the illumination control information is supplied from the main control system 30 to the modulation controller 31, the modulation controller 31 distributes the inclination angles of the mirror elements 3A to 3G of the spatial light modulator 13 according to the illumination condition. Read information about combinations. Then, according to the information on the emission timing of the illumination light IL supplied from the main control system 30 (information corresponding to the light emission trigger pulse TP), the mirror elements 3A to 3G of the spatial light modulator 13 every predetermined number of pulses m. The mirror elements 3A to 3G of the spatial light modulator 13 are controlled so as to change the combination of the inclination angle distributions. The predetermined number of pulses m is a number smaller than the minimum number of pulses that is the number of pulse lights necessary for exposing a predetermined point in the exposure area.

In the present embodiment, even if the intensity distribution in the cross section of the illumination light IL from the light source 7 gradually changes with time, the influence of the unevenness of the pupil intensity distribution can be reduced.

In the above embodiment, the timing of changing the combination of the tilt angle distributions of the mirror elements 3A to 3G of the spatial light modulator 13 is changed every time the illumination light IL is emitted by m pulses. It does not have to be constant during one scanning exposure, and may change gradually, for example.

As in the above-described embodiment, the two-pole illumination in the X direction in FIG. 7A, the normal illumination in FIG. 7B, the annular illumination in FIG. 7C, and the four-pole in FIG. Even in the case of performing illumination or the like, the modulation control unit 31 reflects the spatial light that reflects the illumination light IL that is condensed on each part of the secondary light source on the illumination pupil plane 22 every time the illumination light IL is emitted by m pulses. The combination of the mirror elements 3 of the modulator 13 is changed to a different combination. As a result, the unevenness of the integrated light intensity distribution of the secondary light source formed on the illumination pupil plane 22 is reduced.

The operational effects of this embodiment are as follows.

(1) The exposure apparatus 100 of FIG. 1 of the present embodiment illuminates a pattern using a plurality of pulsed light from the light source device 7 that supplies pulsed light, and the substrate W is irradiated with the plurality of pulsed light via the pattern. A spatial light modulator 13 having a plurality of optical elements 3 that are two-dimensionally arranged and individually controlled, and that emits light by applying spatial light modulation to incident light. A pupil intensity distribution forming optical system 14 that forms a pupil intensity distribution on a predetermined surface based on light through the spatial light modulator 13, and an optical element drive that individually controls and drives the states of the plurality of optical elements 3 And the optical element driving unit (4, 31) has a minimum number of pulses of the plurality of pulsed light exposed to each point of the exposed region on the substrate W. While the light is emitted, the state of the plurality of optical elements 3 is changed.

According to this embodiment, the use efficiency of the illumination light IL is maintained high by individually controlling the angle of the illumination light IL (giving spatial modulation) by the plurality of mirror elements 3 of the spatial light modulator 13. Thus, the illumination condition can be controlled by controlling the intensity distribution of the illumination light IL on the entrance surface of the fly-eye lens 15 and, consequently, the light intensity distribution on the illumination pupil plane 22 that is the exit surface of the fly-eye lens 15. In addition, during one scanning exposure, while the illumination light IL with the minimum number of pulses is emitted, the angle of the light from the plurality of mirror elements 3 is switched to a combination of different angles, whereby a spatial light modulator. The effect of uneven pupil intensity distribution is reduced by compensating for the lack of the wavefront division number due to the time division effect. In other words, in the present embodiment, the influence of the unevenness of the pupil intensity distribution is reduced by using a temporal averaging effect by superimposing a plurality of pupil intensity distributions on the illumination pupil plane in a time division manner. Further, as described above, since the spatial light modulator 13 serves as both the light intensity distribution forming member and the pupil intensity distribution unevenness reducing member, the configuration of the illumination optical system ILS is not complicated. Even when the number of wavefront divisions by the spatial light modulator is sufficient, it is possible to further reduce the influence of the unevenness of the pupil intensity distribution.

(2) In the embodiment of FIG. 1, the illumination pupil plane 22 is a predetermined plane and the intensity distribution of the illumination light IL on the illumination pupil plane 22 is controlled, so that the illumination conditions can be controlled accurately. However, a plane conjugate with the illumination pupil plane 22 may be a predetermined plane. Furthermore, the surface near the illumination pupil plane 22 or the plane near the conjugate plane with the illumination pupil plane 22 may be regarded as the predetermined plane, and the light intensity distribution on these planes may be controlled.

When the fly-eye lens 15 is used, the light intensity distribution on the entrance surface of the fly-eye lens 15 is substantially the same as the light intensity distribution on the exit surface (illumination pupil plane 22). Therefore, the incident surface of the fly-eye lens 15 or a surface in the vicinity thereof can be regarded as a predetermined surface.

(3) Further, in the embodiment of FIG. 1, as an optical device including a plurality of optical elements, a space including a plurality of mirror elements 3 (reflective elements) including a reflective surface having a variable inclination angle that reflects the illumination light IL. An optical modulator 13 is used. Thus, when using a reflective surface, the utilization efficiency of illumination light IL is high.

(4) Since the reflection surface of each mirror element 3 of the spatial light modulator 13 of FIG. 1 has a variable inclination angle around two orthogonal axes, the reflected light from each mirror element 3 is converted to the prism 12 and the relay. It can be guided to an arbitrary two-dimensional position on the entrance plane of the fly-eye lens 15 and thus on the illumination pupil plane 22 via the optical system 14. Therefore, it is possible to set an arbitrary illumination condition with high accuracy while maintaining the utilization efficiency of the illumination light IL at almost 100%.

Note that the inclination angle of each mirror element 3 may be controlled only by the inclination angle around at least one axis (for example, an axis parallel to the X axis in FIG. 1). When only the tilt angle around one axis can be controlled, the reflected light from the plurality of mirror elements 3 in each row of the spatial light modulator 13 is converted into a corresponding one row region on the incident surface of the fly-eye lens 15. What is necessary is just to condense to either. Further, when there is no portion that collects the illumination light IL in the corresponding one row region, the inclination angle of the mirror element 3 corresponding to that row is set so that the reflected light deviates from the incident surface of the fly-eye lens 15. You only have to set it. In this case, the utilization efficiency of the illumination light IL is somewhat reduced, but the control of the spatial light modulator 13 is simplified.

(5) Instead of the spatial light modulator 13, a liquid crystal cell including a plurality of pixels (transmission elements) for controlling the amount of transmitted light can be used. In this case, controlling the transmittance for light passing through each pixel is spatial modulation.

(6) Instead of the spatial light modulator 13, it is also possible to use the above-mentioned spatial light modulator including a plurality of phase elements (variable step elements or the like) for controlling the phase of the passing light. A spatial light modulator including this phase element can be used as a diffractive optical element having a variable diffraction pattern.

(7) Also, the illumination optical system ILS of FIG. 1 is disposed in the vicinity of the spatial light modulator 13 and deflects in the direction in which the illumination light IL is incident on the plurality of mirror elements 3 (or on the plurality of mirror elements 3 side). A first reflecting surface 12a (first surface) and a second reflecting surface 12b (second surface) for deflecting reflected light through the plurality of mirror elements 3 in a direction to enter the irradiated surface (reticle surface). A prism 12 (optical member) is included. Therefore, each optical member constituting the illumination optical system ILS can be arranged along the same straight line or a bent line bent 90 ° in the middle, so that the illumination optical system ILS can be easily designed and manufactured.

(8) Further, in the above embodiment, for example, the number of irradiation pulses of the illumination light IL for each point on the reticle surface is N (N is an integer of 2 or more), and the illumination light IL is m pulses (m is 1 or more). (Integer) A combination of tilt angles of the plurality of mirror elements 3 each time light is emitted, and consequently, an angle distribution (illumination control pattern) of the illumination light IL from the plurality of mirror elements 3 is M patterns defined by the expression (3). It has been switched to. In this case, the combination of the tilt angles of the plurality of mirror elements 3 of the spatial light modulator 13 is only set periodically corresponding to one of the M illumination control patterns, and between the minimum number of pulses. The pupil intensity distribution states at are different from each other. Therefore, it is possible to efficiently reduce the cumulative unevenness of the pupil intensity distribution.

Note that the number of combinations of the tilt angles of the plurality of mirror elements 3 (and thus the illumination control pattern) may be N. In this case, every time the illumination light IL is emitted by one pulse, the combination of the tilt angles of the plurality of mirror elements 3 is periodically switched to any one of the N combinations, thereby reducing the number of pulses between the minimum number of pulses. The pupil intensity distribution states of are all different. Therefore, the cumulative unevenness of the pupil intensity distribution can be greatly reduced.

(9) Since the illumination optical system ILS of FIG. 1 includes the fly-eye lens 15 (optical integrator) that illuminates the reticle surface with the illumination light IL from the illumination pupil plane 22, the reticle surface The uniformity of the illuminance distribution is improved.

(10) Further, a light source 7 for supplying the illumination light IL to the illumination optical system ILS, a power supply control unit 32, and a main control system 30 are provided. Therefore, the pulse emission timing of the light source 7 can be easily controlled with high accuracy.

(11) The exposure apparatus 100 of the above embodiment is an exposure apparatus that projects an image of the reticle surface (first surface) onto the upper surface (second surface) of the wafer W, and the reticle surface is pulsed. An illumination optical system ILS that illuminates with illumination light IL, and a projection optical system PL that forms an image of the reticle surface on the wafer W based on light from the illumination region 26 formed on the reticle surface by the illumination optical system ILS. And. In this case, the reticle is illuminated with the illumination light IL through the secondary light source in which the unevenness of the cumulative pupil intensity distribution is reduced. Therefore, the wafer W is exposed under stable illumination conditions (exposure conditions), and a final device can be manufactured with high accuracy.

Next, in the above embodiment, the following modifications are possible.

(1) The exposure apparatus 100 of the above embodiment may be applied to a step-and-repeat type exposure apparatus such as a stepper. In this case, wafer stage WST in FIG. 1 only needs to have a function of moving in steps in the X and Y directions.

(2) In place of the fly-eye lens 15 which is the wavefront division type integrator of FIG. 1, a rod type integrator as an internal reflection type optical integrator may be used. In this case, as shown by the illumination optical system ILSA in FIG. 8A, a condensing optical system 51 is added on the reticle R side with respect to the relay optical system 14, and the reflection surface of the spatial light modulator 13 (of the mirror element 3). The rod-type integrator 50 is arranged so that the incident end is positioned near the conjugate plane.

Further, a relay optical system (relay lens 18) for forming an image of the reticle blind 17 (field stop) arranged on the exit end face of the rod integrator 50 or in the vicinity of the exit end face on the pattern surface (reticle surface) of the reticle R. , A mirror 19 and a condenser optical system 20). Other configurations of the illumination optical system ILSA are the same as those of the illumination optical system ILS in FIG. 8A, the secondary light source is formed on the pupil plane 22 of the relay optical system 14 and the condensing optical system 51 (the virtual image of the secondary light source is formed in the vicinity of the incident end of the rod integrator 50). )

(3) Also, in the illumination optical system ILS of FIG. 1, the prism 12 is used. However, instead of the prism 12, a mirror having reflecting

surfaces

12a and 12b may be installed on the optical path of the illumination light IL. . Further, as shown in FIG. 8B, the prism 12 may be omitted. In the configuration of FIG. 8B, the illumination light IL is irradiated from the oblique direction to the many mirror elements 3 of the spatial light modulator 13, and the illumination light IL reflected by the many mirror elements 3 is applied to the optical axis AXI. Along the relay optical system 14 and supplied to a fly-eye lens (not shown).

(4) Further, as the spatial light modulator 13, for example, a spatial light modulator which is two-dimensionally arranged and can individually control the height of the reflection surface can be used. As such a spatial light modulator, for example, Japanese Patent Laid-Open No. 6-281869 and US Pat. No. 5,312,513 corresponding thereto, and Japanese Patent Laid-Open No. 2004-520618 and US Pat. The spatial light modulator disclosed in FIG. 1d of Japanese Patent No. 6,885,493 can be used. In these spatial light modulators, a two-dimensional height distribution is formed by a plurality of phase elements (optical elements), so that the same action as that of a phase type diffraction grating can be given to incident light.

(5) A spatial light modulator having a plurality of reflection surfaces arranged two-dimensionally as described above is disclosed in, for example, JP-T-2006-513442 and US Pat. No. 6,891,655 corresponding thereto. Alternatively, it may be modified in accordance with the disclosure of JP 2005-524112 A and US Patent Publication No. 2005/0095749 corresponding thereto.

Further, when a device (electronic device, microdevice) such as a semiconductor device is manufactured using the exposure apparatus of the above embodiment, the device performs function / performance design of the device as shown in FIG. A mask pattern (reticle) is manufactured based on this design step 222, a substrate (wafer) is manufactured as a substrate of the device 223, and the exposure apparatus 100 (projection exposure apparatus) of the above-described embodiment is used to form a mask pattern. Substrate exposure step, development step of the exposed substrate, substrate processing step 224 including heating (curing) and etching step of the developed substrate, device assembly step (dicing process, bonding process, packaging process, etc.) 225) and inspection step 226 etc. It is concrete.

In other words, the device manufacturing method includes a step of exposing the wafer W using the exposure apparatus 100 of the above embodiment, and a step of processing the exposed wafer W (step 224).

Furthermore, the device manufacturing method is a device manufacturing method including a lithography process, and the exposure apparatus 100 of the above embodiment is used in the lithography process. According to these device manufacturing methods, since the uneven exposure amount is reduced, the device can be manufactured with high accuracy.

In the above-described embodiment, a wavefront division type micro fly's eye lens (fly eye lens) having a plurality of minute lens surfaces is used as the optical integrator. Instead, an internal reflection type optical integrator (typically Specifically, a rod type integrator) may be used. In this case, the condensing lens is arranged on the rear side of the relay optical system 14 so that the front focal position thereof coincides with the rear focal position of the relay optical system 14, and at or near the rear focal position of the condensing lens. The rod-type integrator is arranged so that the incident end is positioned. At this time, the injection end of the rod-type integrator is positioned at the reticle blind 17. When a rod type integrator is used, a position optically conjugate with the position of the aperture stop AS of the projection optical system PL in the imaging optical systems 18 to 20 downstream of the rod type integrator can be called an illumination pupil plane. . In addition, since a virtual image of the secondary light source of the illumination pupil plane is formed at the position of the entrance surface of the rod integrator, this position and a position optically conjugate with this position are also called the illumination pupil plane. Can do.

The present invention can also be applied to an immersion type exposure apparatus disclosed in, for example, International Publication No. 99/49504 pamphlet. In this case, as a method for filling the liquid in the optical path between the projection optical system and the photosensitive substrate, a method for locally filling the liquid as disclosed in the pamphlet of International Publication No. WO99 / 49504, A method of moving a stage holding a substrate to be exposed as disclosed in Kaihei 6-124873 in a liquid tank, or a predetermined stage on a stage as disclosed in JP-A-10-303114. A method of forming a liquid tank having a depth and holding the substrate therein can be employed. In the above-described embodiment, a so-called polarization illumination method disclosed in US Publication Nos. 2006/0170901 and 2007/0146676 can be applied.

The illumination optical apparatus of the present invention can also be applied to a proximity type exposure apparatus that does not use a projection optical system.

Further, the present invention is not limited to the application to the manufacturing process of a semiconductor device. For example, a manufacturing process such as a liquid crystal display element and a plasma display, an imaging element (CMOS type, CCD, etc.), a micromachine, a MEMS ( (Micro-electro-mechanical systems), thin film magnetic heads, and various devices (electronic devices) such as DNA chips can be widely applied. As described above, the present invention is not limited to the above-described embodiment, and various configurations can be taken without departing from the gist of the present invention.

The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention. In addition, each component of the above-described embodiment can be any combination.

Claims

An exposure apparatus that illuminates a pattern using a plurality of pulsed light from a light source device that supplies pulsed light and exposes a substrate with the plurality of pulsed light via the pattern,
A spatial light modulator that has a plurality of optical elements that are two-dimensionally arranged and individually controlled, and that emits light by applying spatial light modulation to incident light;
A pupil intensity distribution forming optical system that forms a pupil intensity distribution on a predetermined plane based on light passing through the spatial light modulator;
An optical element driving section for individually controlling and driving the states of the plurality of optical elements;
With
The optical element driving unit changes the state of the plurality of optical elements while the minimum number of pulses of the plurality of pulsed light exposed to each point of the exposed region on the substrate is emitted. An exposure apparatus.
The optical element driving unit controls and drives the plurality of optical elements so that the state of the plurality of optical elements becomes a plurality of states while the minimum number of pulses is emitted. Item 4. The exposure apparatus according to Item 1.
The exposure apparatus according to claim 2, wherein the number of the plurality of states is smaller than the minimum pulse number.
4. The exposure apparatus according to claim 2, wherein the optical element driving unit controls and drives the plurality of optical elements so that a plurality of pupil intensity distributions are superimposed on the predetermined surface in a time division manner.
A storage unit storing information on the plurality of states of the plurality of optical elements;
5. The exposure apparatus according to claim 2, wherein the optical element driving unit controls and drives the plurality of optical elements based on the information stored in the storage unit. 6.
In each of the plurality of states of the plurality of optical elements, the pupil intensity distribution formed on the predetermined surface via the pupil intensity distribution forming optical system is a non-uniform distribution. The exposure apparatus according to any one of claims 2 to 5.
A projection optical system for projecting an image of the pattern onto the substrate;
The exposure apparatus according to claim 1, wherein the predetermined surface is a surface optically conjugate with an exit pupil of the projection optical system or a surface equivalent to the conjugate surface. .
An optical integrator disposed in an optical path between the spatial light modulator and the pattern,
8. The exposure apparatus according to claim 7, wherein the predetermined surface is set at a position near the incident surface of the optical integrator or a position optically conjugate with the position near the predetermined surface.
The exposure apparatus according to any one of claims 1 to 8, wherein the optical element driving unit controls and drives individual postures of the plurality of optical elements.
The plurality of optical elements comprises a plurality of reflective elements;
The exposure apparatus according to claim 9, wherein the reflecting element includes a reflecting surface having a variable inclination angle for reflecting the pulsed light.
11. The exposure apparatus according to claim 1, wherein each point of the exposure area is exposed with a pulse number equal to or greater than the minimum pulse number.
An exposure step of exposing the substrate to the pattern using the exposure apparatus according to any one of claims 1 to 11,
Developing the substrate to which the pattern has been transferred, and forming a mask layer having a shape corresponding to the pattern on the surface of the substrate;
And a processing step of processing the surface of the substrate through the mask layer.