Optical apparatus, exposure apparatus, and processing apparatus

Abstract

This optical apparatus comprises: a first wavelength conversion optical element (72a) on which first incident light including light having a first wavelength is incident, and which emits first emission light including light having a second wavelength different from the first wavelength; a second wavelength conversion optical element (72b) on which second incident light including light having a third wavelength is incident, and which emits second emission light including light having a fourth wavelength different from the third wavelength; a synthesis device which synthesizes at least part of the first emission light and at least part of the second emission light and emits synthesized light; and a control device (80) that moves the incident positions of the first and the second incident light such that the movement state of the first incident light on the incident surface of the first wavelength conversion optical element (72a) is different from the movement state of the second incident light on the incident surface of the second wavelength conversion optical element (72b).　Thus, the wavelength of the incident light can be converted in an undamaged portion of the wavelength conversion optical element, thereby making it possible to maintain wavelength conversion accuracy.

Description

Optical apparatus, exposure apparatus, and processing apparatus

[0001] This relates to optical devices, exposure devices, and processing devices.

[0002] Conventionally, in the lithography process for manufacturing electronic devices (microdevices) such as liquid crystal and organic EL display panels and semiconductor elements (integrated circuits, etc.), step-and-repeat projection exposure equipment (so-called steppers) or step-and-scan projection exposure equipment (so-called scanning steppers, also called scanners) have been used. These types of exposure equipment project a mask pattern for electronic devices onto a photosensitive layer coated on the surface of a substrate to be exposed (hereinafter simply referred to as a substrate), such as a glass substrate, semiconductor wafer, printed circuit board, or resin film.

[0003] In this type of exposure apparatus, a substrate (hereinafter collectively referred to as "substrate") such as a glass plate or wafer with a photosensitive material coated on its surface is placed on a substrate stage device as the object to be exposed. Then, pulsed light is irradiated onto a spatial light modulation element on which a circuit pattern has been formed, and the pulsed light transmitted through the spatial light modulation element is irradiated onto the substrate through an optical system such as a projection lens, thereby transferring the circuit pattern onto the substrate (see, for example, Patent Document 1).

[0004] Japanese Patent Publication No. 2006-171426

[0005] According to the first aspect of the disclosure, the optical device includes: a first wavelength-converting optical element that receives first incident light including light having a first wavelength and emits first output light including light having a second wavelength different from the first wavelength; a second wavelength-converting optical element that receives second incident light including light having a third wavelength and emits second output light including light having a fourth wavelength different from the third wavelength; a combining device that combines at least a portion of the first output light and at least a portion of the second output light and emits combined light; and a control device that moves the incident position of the first incident light within the incident plane of the first wavelength-converting optical element and moves the incident position of the second incident light within the incident plane of the second wavelength-converting optical element, wherein the control device makes the movement state of the first incident light on the incident plane of the first wavelength-converting optical element different from the movement state of the second incident light on the incident plane of the second wavelength-converting optical element.

[0006] According to a second aspect of the disclosure, the optical device comprises a first wavelength-converting optical element into which first incident light including light having a first wavelength is incident and which emits first outgoing light including light having a second wavelength different from the first wavelength, and a control device that moves the incident position of the first incident light within the incident plane of the first wavelength-converting optical element along a first path, wherein the first path is a curved path.

[0007] According to a third aspect of the disclosure, the exposure apparatus comprises a light device and a stage for holding an object to be irradiated by the emitted light emitted from the light device.

[0008] According to the fourth aspect of the disclosure, the processing apparatus comprises an optical device, a patterning device for patterning the emitted light emitted from the optical device, and a projection system for projecting the patterned light onto a workpiece, wherein the patterning device patterns the emitted light in synchronization with the emission timing of the emitted light emitted from the optical device.

[0009] Furthermore, the configuration of the embodiments described later may be modified as appropriate, and at least a part of it may be replaced with other components. Moreover, the configuration elements whose arrangement is not particularly limited may be arranged in positions that can achieve their function, not limited to the arrangement disclosed in the embodiments.

[0010] Figure 1 is a diagram showing an overview of the external configuration of the exposure apparatus according to the first embodiment. Figure 2 is a diagram showing an overview of the configuration of the illumination module, projection module, and light modulation unit of the first embodiment. Figure 3 is a diagram showing an overview of the configuration of the exposure module of the first embodiment. Figure 4 is a diagram showing an overview of the configuration of the spatial light modulator of the first embodiment. Figure 5 is a diagram showing an overview of the configuration of the light source unit of the first embodiment. Figure 6 is a diagram showing the detailed configuration of the light source unit of the first embodiment. Figure 7 is a schematic diagram showing the configuration of the first to eighth light source units. Figure 8(A) is a diagram for explaining the region where incident light is incident on the incident surface of the wavelength conversion optical element, and Figure 8(B) is a diagram showing an example of the path of the incident position of the incident light. Figure 9 is an enlarged view of the part enclosed by a circle in Figure 8(B). Figure 10(A) is a diagram showing another example of the path of the incident position of the incident light, and Figure 10(B) is an enlarged view of the part enclosed by an ellipse in Figure 10(A). Figure 11 is a diagram showing an example of the configuration of a retarder. Figure 12 shows an example of the movement path of the incident position of incident light to the wavelength conversion optical element in the second embodiment.

[0011] 《First Embodiment》 [Configuration of Exposure Apparatus] Figure 1 is a diagram showing an overview of the external configuration of the exposure apparatus 1 according to the first embodiment. The exposure apparatus 1 is a device that irradiates an object to be exposed with modulated light. In a particular embodiment, the exposure apparatus 1 is a step-and-scan type projection exposure apparatus, a so-called scanner, which uses a rectangular (square) glass substrate used in liquid crystal display devices (flat panel displays) and the like as the object to be exposed. The glass substrate, which is the object to be exposed, has a length of at least one side or diagonal length of 500 mm or more, and may be a substrate for a flat panel display. The object to be exposed by the exposure apparatus 1 (for example, a substrate for a flat panel display) is developed and then used as a product.

[0012] The exposure apparatus 1 comprises an apparatus body MB and a control system CNT. The apparatus body MB of the exposure apparatus 1 is configured similarly to the apparatus body disclosed, for example, in U.S. Patent Application Publication No. 2008 / 0030702.

[0013] The main body MB of the exposure apparatus 1 includes a base 11, a vibration isolation table 12, a main column 13, a stage 14, an optical table 15, a lighting module 16, a projection module 17, a light source unit 18, an optical fiber 19, and an optical modulation unit 20 (not shown), etc. The control system CNT provides overall control for each component of the main body MB.

[0014] In the following explanation, we will use a three-dimensional Cartesian coordinate system as needed, where the Z-axis direction is defined as the direction parallel to the optical axis of the projection module 17 that irradiates the object to be exposed with light modulated by the light modulation unit 20, and the X-axis direction and Y-axis direction are defined as the directions of a predetermined plane perpendicular to the Z-axis. The X-axis direction and the Y-axis direction are mutually orthogonal (intersecting) directions.

[0015] The base 11 is the base of the exposure apparatus 1 and is installed on the vibration isolation table 12. The base 11 supports the stage 14 on which the object to be exposed is placed, so that it can move in the X-axis direction and the Y-axis direction.

[0016] Stage 14 supports the object to be exposed and, in scanning exposure, is used to precisely position the object with respect to multiple partial images of a circuit pattern projected via the projection module 17. It drives the object to be exposed in six degrees of freedom directions (the X, Y, and Z axis directions and the rotational directions θx, θy, and θz directions relative to each axis). Stage 14 is moved in the X axis direction during scanning exposure and in the Y axis direction when changing the exposure area on the object to be exposed. Multiple exposure areas are formed on the object to be exposed. The exposure apparatus 1 is capable of exposing multiple exposure areas on a single object to be exposed. The configuration of Stage 14 is not particularly limited, but a so-called coarse-fine movement stage apparatus can be used, which includes a gantry-type two-dimensional coarse-movement stage and a fine-movement stage that is driven minutely relative to the two-dimensional coarse-movement stage, as disclosed in U.S. Patent Application Publication No. 2012 / 0057140, etc. In this case, the coarse movement stage allows the object to be exposed to move in three directions of freedom within the horizontal plane, and the fine movement stage allows the object to be finely moved in six directions of freedom.

[0017] The main column 13 supports the optical base plate 15 at the top of the stage 14 (in the positive direction of the Z axis). The optical base plate 15 supports the illumination module 16, the projection module 17, and the light modulation unit 20.

[0018] Figure 2 is a diagram illustrating the general configuration of the lighting module 16, projection module 17, and light modulation unit 20 in this embodiment.

[0019] The lighting module 16 is positioned on top of the optical base plate 15 and connected to the light source unit 18 via an optical fiber 19. In one example of this embodiment, the lighting module 16 includes a first lighting module 16A, a second lighting module 16B, a third lighting module 16C, and a fourth lighting module 16D. In the following description, when the first lighting module 16A to the fourth lighting module 16D are not distinguished, they will be collectively referred to as the lighting module 16.

[0020] Each of the first to fourth lighting modules 16A to 16D guides the light emitted from the light source unit 18 via the optical fiber 19 to the first optical modulation unit 20A, the second optical modulation unit 20B, the third optical modulation unit 20C, and the fourth optical modulation unit 20D, respectively. In the following description, when the first to fourth optical modulation units 20A to 16D are not distinguished, they will be collectively referred to as the optical modulation unit 20. The lighting module 16 illuminates the optical modulation unit 20.

[0021] The light modulation unit 20, which will be described in more detail later, is controlled based on a circuit pattern to be transferred to the object to be exposed, and modulates the illumination light from the illumination module 16. The modulated light modulated by the light modulation unit 20 is guided to the projection module 17. The first light modulation unit 20A to the fourth light modulation unit 20D are arranged at different positions in the XY plane.

[0022] The projection module 17 is positioned below the optical platen 15 and irradiates the object to be exposed, placed on the stage 14, with modulated light modulated by the spatial light modulator 201. The projection module 17 forms an image of the light modulated by the light modulation unit 20 on the object to be exposed, thereby exposing the object. In other words, the projection module 17 projects the pattern on the light modulation unit 20 onto the object to be exposed. In one example of this embodiment, the projection module 17 includes the first projection module 17A, the second projection module 17B, the third projection module 17C, and the fourth projection module 17D, corresponding to the first illumination modules 16A to the fourth illumination modules 16D and the first to fourth light modulation units 20A to the fourth light modulation units 20D described above. In the following description, when the first projection module 17A to the fourth projection module 17D are not distinguished, they will be collectively referred to as the projection module 17.

[0023] The unit comprising the first illumination module 16A, the first light modulation unit 20A, and the first projection module 17A is called the first exposure module. Similarly, the unit comprising the second illumination module 16B, the second light modulation unit 20B, and the second projection module 17B is called the second exposure module. Each exposure module is positioned at different locations on the XY plane, and can expose patterns at different locations on the object to be exposed placed on the stage 14. By moving the stage 14 relative to the exposure modules in the X-axis direction, which is the scanning direction, the entire surface of the object to be exposed or the entire area of ​​the object to be exposed can be scanned and exposed.

[0024] The projection module 17 is also referred to as the projection unit. The projection module 17 (projection unit) may be a 1:1 magnification system that projects the image of the pattern on the light modulation unit 20 at 1:1 magnification, or it may be an enlargement system or a reduction system. Furthermore, it is preferable that the projection module 17 is composed of one or two types of glass materials (particularly quartz or fluorite).

[0025] In addition to the parts described above, the exposure apparatus 1 includes a position measurement unit (not shown) consisting of an interferometer and an encoder, which measures the relative position of the stage 14 with respect to the optical table 15. In addition to the parts described above, the exposure apparatus 1 includes an AF (Auto Focus) unit (not shown) which measures the position of the stage 14 or the object to be exposed on the stage 14 in the Z-axis direction. Furthermore, the exposure apparatus 1 includes an alignment unit (not shown) which measures the relative position of each pattern when superimposing another pattern on a pattern that has already been exposed on the object to be exposed. The AF unit and / or the alignment unit may be configured as a TTL (Through the lens) unit that measures via a projection module.

[0026] Figure 3 is a diagram showing an overview of the configuration of the exposure module in this embodiment. Using the first exposure module as an example, a specific example of the configuration of the illumination module 16, the light modulation unit 20, and the projection module 17 will be described.

[0027] The lighting module 16 comprises a module shutter 161 and an illumination optical system 162. The module shutter 161 switches whether or not to guide pulsed light supplied from the optical fiber 19 to the illumination optical system 162.

[0028] The illumination optical system 162 illuminates the optical modulation unit 20 almost uniformly by emitting pulsed light supplied from the optical fiber 19 to the optical modulation unit 20 via a collimator lens, a fly-eye lens, a condenser lens, and the like. The fly-eye lens wavefront-splits the pulsed light incident on it, and the condenser lens superimposes the wavefront-split light onto the optical modulation unit. The illumination optical system 162 may also include a rod integrator instead of a fly-eye lens.

[0029] The light modulation unit 20 includes a mask. The mask may be a photomask or a spatial light modulator (SLM). The case where the mask is a spatial light modulator will be described below.

[0030] The optical modulation unit 20 comprises a spatial light modulator 201 and an off-light absorbing plate 202. The spatial light modulator 201 includes liquid crystal elements, digital mirror devices (digital micromirror devices, DMDs), magneto-optical spatial light modulators (MOSLMs), etc. The spatial light modulator 201 may be a reflective type that reflects illumination light from the illumination optical system 162, a transmissive type that transmits illumination light, or a diffracting type that diffracts illumination light. The spatial light modulator 201 can modulate the illumination light spatially and temporally.

[0031] The following explanation will use the case where the spatial light modulator 201 is composed of a digital micromirror device (DMD) as an example.

[0032] Figure 4 shows an overview of the configuration of the spatial light modulator 201 of this embodiment. In this figure, the three-dimensional Cartesian coordinate system of the Xm, Ym, and Zm axes will be used for explanation. The spatial light modulator 201 comprises a plurality of micromirrors arranged in the XmYm plane. The micromirrors constitute the elements (pixels) of the spatial light modulator 201. The tilt angle of the spatial light modulator 201 can be changed around the Xm axis and the Ym axis, respectively. For example, the spatial light modulator 201 becomes ON when tilted around the Ym axis and OFF when tilted around the Xm axis.

[0033] The spatial light modulator 201 controls the direction in which incident light is reflected for each element by switching the tilt direction of each micromirror. For example, the digital micromirror device of the spatial light modulator 201 has a pixel count of about 4 Mpixels and can switch between the on and off states of the micromirrors with a period of about 10 kHz.

[0034] The spatial light modulator 201 has multiple elements that are individually controlled at predetermined time intervals. If the spatial light modulator 201 is a DMD, the elements are micromirrors, and the predetermined time interval is the period for switching the on and off states of the micromirrors (for example, a period of 10 kHz).

[0035] Returning to FIG. 3, the off-light absorption plate 202 absorbs the light (off-light) emitted (reflected) from the elements in the off state of the spatial light modulator 201. The light emitted from the elements in the on state of the spatial light modulator 201 is guided to the projection module 17.

[0036] The projection module 17 projects the light emitted from the elements in the on state of the spatial light modulator 201 onto the exposure object. The projection module 17 includes a magnification adjustment unit 171 and a focus adjustment unit 172. The modulated light (modulated light) modulated by the spatial light modulator 201 is incident on the magnification adjustment unit 171.

[0037] The magnification adjustment unit 171 adjusts the magnification of the focal plane 163 of the modulated light emitted from the spatial light modulator 201, that is, the image on the surface of the exposure object, by driving some of the lenses in the optical axis direction.

[0038] The focus adjustment unit 172 drives the entire lens group in the optical axis direction so that the modulated light emitted from the spatial light modulator 201 forms an image on the surface of the exposure object measured by the above-described AF unit, that is, adjusts the imaging position, that is, the focus.

[0039] The projection module 17 projects only the image of the light emitted from the elements in the on state of the spatial light modulator 201 onto the surface of the exposure object. Therefore, the projection module 17 can project and expose the image of the pattern formed by the on elements of the spatial light modulator 201 onto the surface of the exposure object. That is, the projection module 17 can form spatially modulated modulated light on the surface of the exposure object. Further, since the spatial light modulator 201 can switch the on state and the off state of the micromirror at a predetermined period (frequency) as described above, the projection module 17 can form temporally modulated modulated light on the surface of the exposure object. That is, the exposure apparatus 1 performs exposure by changing the state of the virtual pupil substantially at an arbitrary exposure position.

[0040] By driving the stage 14 in the scanning direction in accordance with the period in which the spatial light modulator 201 switches between the on state and the off state of the micromirror, a predetermined pattern can be transferred onto the exposure object.

[0041] [Configuration of Light Source Unit] Fig. 5 is a diagram showing an overview of the configuration of the light source unit 18 of the first embodiment. The light source unit 18 includes a light source device (optical device) 18A and a distribution unit 18B.

[0042] The light source device 18A includes a light emitting part 180, a combining part 182, and a retarder 183.

[0043] The light emitting part 180 emits light of a predetermined wavelength. The light emitted by the light emitting part 180 may be continuous light or pulsed light. Hereinafter, the case where the light emitting part 180 emits pulsed light will be described.

[0044] In the case where the light emitting part 180 emits continuous light, the continuous light may be converted into pulsed light by switching a shutter (not shown), modulation by an acousto-optic modulator (not shown), etc., so that the light emitted from the light emitting part 180 is regarded as substantially pulsed light. Also, pulsed light may be generated electrically by turning on / off the light emitting part 180.

[0045] The light emitting part 180 includes first light source parts 181a to eighth light source parts 181h. Each of the first light source parts 181a to eighth light source parts 181h has a light source and emits pulsed light of a predetermined wavelength. The wavelengths of the pulsed light emitted by the first light source parts 181a to eighth light source parts 181h may be the same as each other or different from each other. In the present embodiment, it is assumed that the wavelengths of the pulsed light emitted by the first light source parts 181a to eighth light source parts 181h are the same as each other. The configurations of each of the first light source parts 181a to eighth light source parts 181h will be described later. In the following description, when the first light source parts 181a to eighth light source parts 181h are not distinguished, they are collectively referred to as the light source part 181.

[0046] The combining part 182 combines the pulsed light emitted from the first light source parts 181a to eighth light source parts 181h included in the light emitting part 180. The combining part 182 generates pulsed light with high intensity (large energy) by combining the pulsed light. The combining part 182 emits the combined pulsed light (hereinafter, may be referred to as combined pulsed light) to the retarder 183.

[0047] The retarder 183 repeatedly splits and combines the pulsed light emitted from the combining unit 182, and by combining pulsed light with different delay times, it changes the time axis distribution of the pulsed light. The retarder 183 emits the pulsed light with the changed time axis distribution to the distribution unit 18B.

[0048] The retarder 183 is also called a delay optical system. The retarder 183 (delay optical system) delays a portion of the pulsed light. Furthermore, the retarder 183 (delay optical system) splits a portion of the pulsed light and guides it into a delay optical path, and by combining the portion of the pulsed light guided into the delay optical path with the other portion of the split pulsed light, it changes the temporal characteristics of the pulsed light.

[0049] The distribution unit 18B includes a rotary switch 1841 and a distributor 1842. The distribution unit 18B distributes the pulsed light emitted from the retarder 183 to each of the multiple optical fibers 19. That is, the distribution unit 18B distributes the pulsed light to multiple exposure modules. The configuration of the distribution unit 18B can be the one described in International Publication No. 2022 / 230847.

[0050] Figure 6 shows the details of the configuration of the light source unit 18 in this embodiment.

[0051] [Configuration of the light-emitting unit 180] The light-emitting unit 180 comprises a first light source unit 181a to an eighth light source unit 181h and a control device 185. Figure 6 shows the first light source unit 181a to the fourth light source unit 181d of the first light source unit 181a to the eighth light source unit 181h. The fifth light source unit 181e to the eighth light source unit 181h have the same configuration as the first light source unit 181a to the fourth light source unit 181d, so their description is omitted.

[0052] The control device 185 outputs control signals to the control units 80a to 80h, each of the first to eighth light source units 181a to 181h, and provides overall control of the first to eighth light source units 181a to 181h.

[0053] [Configuration of the light source unit 181] Figure 7 is a schematic diagram showing the configuration of the first light source unit 181a to the eighth light source unit 181h.

[0054] As shown in Figure 7, the light source unit 181 includes a light source unit 50 that emits seed light, an amplification unit 60 that amplifies the seed light emitted from the light source unit 50 and outputs amplified light, a wavelength conversion unit 70 that converts the wavelength of the amplified light output from the amplification unit 60 and outputs output light, and a control unit 80 that controls the operation of each unit.

[0055] The wavelength, waveform, and power of the seed light and output light can be appropriately set according to the application and function of the device using the light source device 18A. In this embodiment, an example is given in which seed light Ls with a wavelength λ1 = 1064 nm and a power of several mW emitted from the light source unit 50 is amplified to a level of several tens to several hundred watts in the amplification unit 60, and the amplified seed light, i.e., amplified light La, is converted into output light Lv with a wavelength λ3 = 355 nm in the wavelength conversion unit 70 and output.

[0056] The light source unit 50 comprises a laser light source 51 and an external modulator 52. The laser light source 51 generates laser light with a wavelength λ1 = 1064 nm, for example. As the laser light source 51, a DFB (Distributed Feedback) semiconductor laser can be used. A DFB semiconductor laser can be made to oscillate in CW (continuous wave) or pulsed mode, and by controlling the temperature, it can output a single-wavelength laser light with a narrow bandwidth within a predetermined wavelength range. The light source unit 50 shown in Figure 7 outputs pulsed light (or CW light) with a sufficiently long ON time from the laser light source 51, and a portion of it is extracted by an external modulator 52 such as an electro-optical modulator (EOM) or an acousto-optical modulator (AOM) to output pulsed seed light Ls.

[0057] The amplification unit 60 amplifies the seed light Ls emitted from the light source unit 50 to a level of several tens to several hundred watts and emits the amplified light La to the wavelength conversion unit 70. Figure 7 shows a configuration in which three fiber amplifiers 61, 62, and 63 are connected in series, and the seed light Ls is sequentially amplified by these three stages of fiber amplifiers 61, 62, and 63. In this configuration example, single-clad ytterbium-doped fiber amplifiers (YDFAs) are used as the first and second stage fiber amplifiers 61 and 62, and a double-clad YDFA is used as the third stage fiber amplifier 63.

[0058] The first and second stage fiber amplifiers 61 and 62 each include single-clad fibers 610 and 620 for amplification and excitation light sources 615 and 625 for exciting ytterbium (Yb), respectively. The single-clad fibers 610 and 620 consist of a Yb-doped core and a cladding covering the outer circumference of the core, and seed light Ls and excitation light Lp are introduced into the core. For example, semiconductor lasers with a wavelength λ = 975 nm can be used as the excitation light sources 615 and 625.

[0059] The third-stage fiber amplifier 63 includes a double-clad fiber 630 for amplification and an excitation light source 635 for exciting Yb. The double-clad fiber 630 has a Yb-doped core, a first cladding covering the outer circumference of the core, and a second cladding covering the outer circumference of the first cladding. Seed light (for convenience, referred to as signal light) amplified by fiber amplifiers 61 and 62 is introduced into the core, and excitation light Lp emitted from the excitation light source 635 is introduced into the first cladding.

[0060] The first cladding (also called a pumping guide) acts as a multimode waveguide for the excitation light, guiding the high-power multimode laser light emitted from multiple excitation light sources 635 in the axial direction, thereby efficiently exciting the Yb doped in the core.

[0061] The signal light, i.e., amplified light La, which is amplified by the third-stage fiber amplifier 63, is emitted from the amplification unit 60 and incident on the wavelength conversion unit 70.

[0062] The wavelength conversion unit 70 includes a wavelength conversion optical element 71, a wavelength conversion optical element 72, a drive device 721 for moving the wavelength conversion optical element 72 in a plane direction intersecting the optical axis of the amplified light La, a half mirror 73, and a monitor 731. In Figure 7, the wavelength conversion optical elements 72 provided in each of the first to eighth light source units 181a to 181h are shown in parentheses as wavelength conversion optical elements 72a to 72h. Also, the drive devices 721 provided in each of the first to eighth light source units 181a to 181h are shown in parentheses as drive devices 721a to 721h. Also, the monitors 731 provided in each of the first to eighth light source units 181a to 181h are shown in parentheses as monitors 731a to 731h.

[0063] The amplified light La with wavelength λ1 = 1064 nm, incident from the amplification unit 60 to the wavelength conversion unit 70, is focused and incident on the wavelength conversion optical element 71 via a focusing lens. The wavelength conversion optical element 71 is a nonlinear optical crystal that generates the second harmonic of the amplified light La by second harmonic generation (SHG). As the wavelength conversion optical element 71, LBO (LiB ３ O ５ A configuration can be used in which the crystal is used with non-critical phase matching (NCPM).

[0064] When an LBO crystal is used in a noncritical phase matching configuration, no walk-off occurs in the second harmonic with a wavelength of λ² = 532 nm. Therefore, a sufficient interaction length can be ensured, and wavelength conversion can be performed efficiently. Furthermore, since the beam cross-section of the emitted second harmonic does not become elliptical, there is no need to provide a shaping optical element such as a cylindrical lens between the wavelength conversion optical element 71 and the wavelength conversion optical element 72, and wavelength conversion can be performed efficiently in the wavelength conversion optical element 72.

[0065] Furthermore, if the power of the amplified light La output from the amplification unit 60 is low, around 10 W, the wavelength conversion optical element 71 is a PPLN (Periodically Poled LiNbO ３ ) Crystals, or PPLT (Periodically Poled LiTaO) ３), PPKT (Periodically Poled KTiOPO ４ ), a quasi-phase matching (QPM: Quasi Phase Matching) crystal such as a crystal may be used. Even when a QPM crystal is used, wavelength conversion can be efficiently performed, and there is no need to provide a shaping optical element between the wavelength conversion optical element 71 and the wavelength conversion optical element 72.

[0066] The second harmonic generated by the wavelength conversion optical element 71 and the amplified light transmitted through the wavelength conversion optical element 71 without wavelength conversion rotate the polarization plane of either one (for example, the amplified light) by 90 degrees with a two-wavelength wave plate and are condensed and incident on the wavelength conversion optical element 72.

[0067] The wavelength conversion optical element 72 is a non-linear optical crystal that generates a sum frequency of the second harmonic and the amplified light by sum frequency generation (SFG: Sum Frequency Generation). As the wavelength conversion optical element 72, a configuration in which an LBO crystal is used in type I critical phase matching (CPM) is exemplified. As the wavelength conversion optical element 72, BBO (β-BaB ２ O ４ ), a CLBO (CsLiB ６ O １０ ), a crystal can also be used. The amplified light with a wavelength of 1064 nm and the second harmonic with a wavelength of 532 nm incident on the wavelength conversion optical element 72 are wavelength-converted in the process of passing through the wavelength conversion optical element 72, and a third harmonic with a wavelength of λ3 = 355 nm, which is a sum frequency, is generated.

[0068] The third harmonic generated by the wavelength conversion optical element 72 is output from the light source unit 181 as the output light Lv. The light emitted from the wavelength conversion optical element 72 includes the remaining amplified light and the second harmonic that have passed through the wavelength conversion optical element 72 without wavelength conversion. By disposing a dichroic mirror or a prism or the like on the output end side of the wavelength conversion optical element 72 to remove these, only the third harmonic with a wavelength of λ3 = 355 nm can be output from the light source unit 181.

[0069] The timing at which the light source unit 181 emits pulsed light is controlled by the control unit 80 based on a control signal from the control device 185 (see Figure 6) provided in the light-emitting unit 180. The control units 80 provided in each of the first to eighth light source units 181a to 181h are shown in parentheses as control units 80a to 80h.

[0070] In this embodiment, the control device 185 outputs control signals to the control units 80a to 80h of the first to eighth light sources 181a to eighth light sources 181h so that they emit pulsed light in synchronization with each other. In other words, the pulsed light emission timing of the first light source 181a, the second light source 181b, the third light source 181c, the fourth light source 181d, the fifth light source 181e, the sixth light source 181f, the seventh light source 181g, and the eighth light source 181h all coincide.

[0071] The control device 185 emits pulsed light from the first light source unit 181a to the eighth light source unit 181h at predetermined time intervals T1. The predetermined time interval T1 is the period during which the on and off states of the micromirrors are switched when the spatial light modulator 201 is a DMD. That is, the spatial light modulator 201 patterns the emitted light in synchronization with the emission timing of the emitted light emitted from the light source unit 18.

[0072] In the light source unit 181 configured as described above, the wavelength conversion optical element 72 is temperature-controlled, but it is still susceptible to damage from incident light. Therefore, in the light source unit 181, the control unit 80, based on a control signal from the control device 185, moves the wavelength conversion optical element 72 at predetermined intervals using the drive device 721 so that the incident position of the incident light on the wavelength conversion optical element 72 is a position where the incident light has not yet entered. In this embodiment, the wavelength conversion optical element 72 is moved by the drive device 721, but the wavelength conversion optical element 71 may also be moved by the drive device.

[0073] The drive device 721 moves the wavelength conversion optical element 72 in a plane direction intersecting the optical axis of the incident light. Specifically, the drive device 721 drives the wavelength conversion optical element 72 in a plane perpendicular to the optical axis of the incident light. More specifically, the drive device 721 moves the wavelength conversion optical element 72 such that the incident position of the incident light onto the wavelength conversion optical element 72 moves along a predetermined path PTH1 at a speed V1.

[0074] Figure 8(A) is a diagram illustrating the region where incident light is incident on the incident surface of the wavelength conversion optical element 72, and Figure 8(B) is a diagram showing an example of the path PTH1 of the incident position of the incident light. In Figure 8(A), the black circle indicates the position of the center of the incident light (optical axis OAX of the incident light).

[0075] As shown in Figure 8(A), after a predetermined time has elapsed since the incident light entered region R1 on the incident surface of the wavelength conversion optical element 72, the control unit 80 moves the region on the incident surface of the wavelength conversion optical element 72 where the incident light enters from region R1 to region R2 on the incident surface, which is different from region R1, in the direction indicated by arrow AR1 (-Y1 direction), by a distance d1 step. Regions R1 and R2 may partially overlap or may be separated. Furthermore, after a predetermined time has elapsed since the incident light entered region R2 on the incident surface of the wavelength conversion optical element 72, the control unit 80 moves the region on the incident surface of the wavelength conversion optical element 72 where the incident light enters from region R2 on the incident surface to region R3, in the direction indicated by arrow AR2 (+X1 direction), by a distance d1 step. Similarly, the control unit 80 moves the region on the incident surface of the wavelength conversion optical element 72 where incident light is incident in a distance d1 step at a predetermined time interval, in the direction indicated by arrow AR2 (+X1 direction), from region R3 on the incident surface to region R4, then to region R5. For example, the control unit 80 moves the region on the incident surface of the wavelength conversion optical element 72 where incident light is incident in a 1 μm step at a time interval. The control unit 80 also moves the region on the incident surface of the wavelength conversion optical element 72 where incident light is incident in a distance d1 step at a time, in the direction indicated by arrow AR3 (+Y1 direction), from region R5 on the incident surface to region R6.

[0076] The control unit 80 moves the incident position of the incident light to the wavelength conversion optical element 72 along the path PTH1 from the starting point SP to the ending point EP, as shown by the arrows in Figure 8(B). By moving the wavelength conversion optical element 72 in this way and changing the incident position of the incident light, wavelength conversion can be performed in the portion of the wavelength conversion optical element 72 that has not been damaged.

[0077] Here, as the wavelength-converting optical element 72 moves while being damaged by the incident light, the emission angle and position of the pulsed light emitted from the wavelength-converting optical element 72 shift at points where the direction of movement changes significantly, as circled in Figure 8(B) (hereinafter sometimes referred to as moving inflection points). For example, at moving inflection point IP1, where the direction of movement of the incident light at the incident surface of the wavelength-converting optical element 72 switches from the -Y1 direction to the X1 direction, and at moving inflection point IP2, where the direction of movement of the incident light switches from the +X1 direction to the +Y1 direction, the emission angle and position of the pulsed light emitted from the wavelength-converting optical element 72 shift. This causes optical effects such as fluctuations in the illuminance (power) of the pulsed light emitted from the wavelength-converting optical element 72.

[0078] As described above, in the light source device 18A, pulsed light from the first light source unit 181a to the eighth light source unit 181h is combined in the combining unit 182. Therefore, if the pulsed light emitted from each of the first light source unit 181a to the eighth light source unit 181h is pulsed light based on incident light incident on the moving inflection point of the wavelength conversion optical element 72, the illuminance (power) of the combined pulsed light may fluctuate, which may affect the quality of the pattern transferred by the spatial light modulator 201 to the object to be exposed. Therefore, in this embodiment, the movement state of the incident light on the incident surface of the first light source unit 181a to the eighth light source unit 181h is made different for each.

[0079] Specifically, the control device 185 causes the timing for switching the direction of movement of incident light on the incident surface of the wavelength conversion optical elements 72a to 72h of the first light source unit 181a to the eighth light source unit 181h to be different for each. To facilitate the explanation, the first light source unit 181a and the second light source unit 181b will be described.

[0080] The control device 185 sets the timing for switching the direction of movement of incident light on the incident surface of the wavelength conversion optical element 72a of the first light source unit 181a to be different from the timing for switching the direction of movement of incident light on the incident surface of the wavelength conversion optical element 72b of the second light source unit 181b. The control device 185 also sets the timing for switching the direction of movement of incident light on the incident surfaces of the wavelength conversion optical elements 72c to 72h of the other third light source units 181c to eighth light source units 181h to be different for each of them.

[0081] Since the incident light at the incident surfaces of the first light source unit 181a and the second light source unit 181b moves by moving their respective wavelength conversion optical elements 72a and 72b, the control device 185 can be said to be setting the timing at which the direction of movement of the wavelength conversion optical element 72a of the first light source unit 181a changes by a predetermined amount or more to the timing at which the direction of movement of the wavelength conversion optical element 72b of the second light source unit 181b changes by a predetermined amount. The predetermined amount is an amount that exceeds unintended changes such as errors.

[0082] This allows the timing at which the incident light to the first light source unit 181a to the eighth light source unit 181h is incident on the moving inflection point to be different from each other. As a result, the fluctuation in the illuminance (power) of the combined pulsed light can be reduced to 1 / 8 of what it would be if the incident light to the first light source unit 181a to the eighth light source unit 181h were incident on the moving inflection point at the same time. In other words, fluctuations in the power of the combined pulsed light can be suppressed.

[0083] In Figure 8(A), the incident region of the incident light moved from region R1 to region R3 by passing through region R2 and moving at a right angle, but this is not the only case.

[0084] Figure 9 is an enlarged view of the area circled in Figure 8(B). As shown in Figure 9, the incident position of the incident light may be moved in an arc shape, as shown in regions R2-1 to R2-6, from region R1 to region R3. In this case, the incident light is incident on the moving inflection point while the region into which the incident light is incident moves from region R1 to region R3. In this case, for example, the control device 185 makes the timing at which the incident light to the first light source unit 181a is incident on the center (moving inflection point) of region R2-1 of the wavelength conversion optical element 72a different from the timing at which the incident light to the second light source unit 181b is incident on the center (moving inflection point) of region R2-1 of the wavelength conversion optical element 72b.

[0085] Furthermore, the path of the incident light's incident position is not limited to that shown in Figure 8(B). Figure 10(A) shows another example of the path of the incident light's incident position. As shown in Figure 10(A), the incident position of the incident light may move in an arc rather than at a right angle. Figure 10(B) is an enlarged view of the area enclosed by the ellipse in Figure 10(A). In Figure 10(B), the region into which the incident light enters is shown by a circle, and the position of the center of the incident light is shown by a black circle.

[0086] As shown in Figure 10(B), the incident position of the incident light moves in an arc shape between region R11 and region R14. For example, the direction of movement when the region into which the incident light is incident moves from region R11 to region R12 (indicated by arrow AR11), and the direction of movement when the region into which the incident light is incident moves from region R12 to region R13 (indicated by arrow AR12), change by a predetermined amount or more. That is, while the region into which the incident light is incident moves from region R11 to region R14, the incident light is incident at the moving inflection point. In this case, for example, the control device 185 makes the timing at which the incident light to the first light source unit 181a is incident at position P1 (moving inflection point) of the wavelength conversion optical element 72a different from the timing at which the incident light to the second light source unit 181b is incident at position P1 (moving inflection point) of the wavelength conversion optical element 72b. Furthermore, the timing at which the light incident on the first light source unit 181a is incident on the position P2 (moving inflection point) of the wavelength conversion optical element 72a is made different from the timing at which the light incident on the second light source unit 181b is incident on the position P2 (moving inflection point) of the wavelength conversion optical element 72b.

[0087] The half-mirror 73 directs a portion of the wavelength-converted pulsed light to the monitor 731. The monitor 731 monitors the illuminance of the pulsed light emitted from the wavelength-converting optical element 72 and feeds it back to the control unit 80. Based on the illuminance input from the monitor 731, the control unit 80 adjusts the illuminance of the seed light emitted from the laser light source 51.

[0088] [Configuration of the Combination Unit 182] Returning to Figure 6, the combination unit 182 comprises a prism mirror 1821, a polarizing beam splitter 1822, a wave plate 1823, a wave plate 1824, a prism mirror 1825, a polarizing beam splitter 1826, and a prism mirror 1827. The prism mirror 1821 guides the pulsed light (s-polarized) emitted from the first light source unit 181a to the polarizing beam splitter 1822. The wave plate 1823 changes the polarization state of the pulsed light (s-polarized) emitted from the second light source unit 181b and guides the pulsed light (p-polarized) to the polarizing beam splitter 1822. The polarizing beam splitter 1822 transmits the pulsed light when the incident pulsed light is p-polarized, and reflects the pulsed light when the incident pulsed light is s-polarized.

[0089] The polarizing beam splitter 1822 reflects the pulsed light (s-polarized) reflected by the prism mirror 1821 and guides it to the waveplate 1824. The polarizing beam splitter 1822 also transmits the pulsed light (p-polarized) that has passed through the waveplate 1823 and guides it to the waveplate 1824. In other words, pulsed light emitted from the first light source unit 181a is incident on the waveplate 1824 as s-polarized (0-degree linearly polarized), and pulsed light emitted from the second light source unit 181b is incident on the waveplate 1824 as p-polarized (90-degree linearly polarized). In short, two types of pulsed light with mutually orthogonal polarization directions are combined in a 50 / 50 ratio and incident on the waveplate 1824.

[0090] The waveplate 1824 rotates the polarization direction of the incident pulsed light. The waveplate 1824 rotates the polarization direction of the incident s-polarized light (0-degree linear polarization) to +45-degree linear polarization, and rotates the polarization direction of the incident p-polarized light (90-degree linear polarization) to -45-degree linear polarization.

[0091] Two types of pulsed light are emitted from the waveplate 1824: one with +45 degree linear polarization and the other with -45 degree linear polarization. The two types of pulsed light emitted from the waveplate 1824 are reflected by the prism mirror 1825 and guided to the polarization beam splitter 1826.

[0092] The polarizing beam splitter 1826 emits the incident pulsed light to the retarder 183. Here, the polarizing beam splitter 1826 is incident on the +45-degree linearly polarized light from the first light source 181a and the -45-degree linearly polarized light from the second light source 181b. The polarizing beam splitter 1826 reflects the s-polarized components of the incident pulsed light, that is, the s-polarized light of the +45-degree linearly polarized light and the s-polarized light of the -45-degree linearly polarized light, and emits them to the retarder 183. The polarizing beam splitter 1826 transmits the p-polarized components of the incident pulsed light, that is, the p-polarized light of the +45-degree linearly polarized light and the p-polarized light of the -45-degree linearly polarized light, and emits them to the retarder 183 via the prism mirror 1827.

[0093] In other words, the polarizing beam splitter 1822 combines the pulsed light emitted by the first light source unit 181a and the pulsed light emitted by the second light source unit 181b coaxially and emits it to the retarder 183. Although the polarizing beam splitter 1822 is described as combining the pulsed light emitted by the first light source unit 181a and the pulsed light emitted by the second light source unit 181b coaxially, it is also possible to combine them with their respective optical axes slightly offset, i.e., paraxially. When the polarizing beam splitter 1822 is plate-type, when p-polarized pulsed light passes through the polarizing beam splitter 1822, its optical axis is slightly shifted. This occurs because the pulsed light passing through the PBS is slightly refracted by the refractive index of the PBS, and light with an optical axis slightly shifted from the incident optical axis is emitted from the PBS. By combining the paraaxial beams, the energy (power) per unit area of ​​the pulsed light striking the optical element, i.e., the energy density, can be dispersed. As a result, degradation, including deformation of the optical element, can be suppressed.

[0094] Similarly, the combining unit 182 combines the pulsed light emitted by the third light source unit 181c and the pulsed light emitted by the fourth light source unit 181d coaxially and emits it to the retarder 183.

[0095] In other words, the light source device 18A is equipped with a combining device. The combining unit 182 described above is an example of a combining device. The combining device combines pulsed light emitted from multiple light sources.

[0096] In the following explanation, the pulsed light emitted from the polarizing beam splitter 1826 to the retarder 183 is also referred to as retarder incident light 183LI. Of the retarder incident light 183LI, the pulsed light emitted from the polarizing beam splitter 1826 to the retarder 183 without passing through the prism mirror 1827 is also referred to as the first retarder incident light 183LI1, and the pulsed light emitted from the polarizing beam splitter 1826 to the retarder 183 via the prism mirror 1827 is also referred to as the second retarder incident light 183LI2.

[0097] In other words, the retarder 183 is incident on two types of pulsed light: the first retarder incident light 183LI1 and the second retarder incident light 183LI2, which are emitted from different light sources 181. As described above, both the first retarder incident light 183LI1 and the second retarder incident light 183LI2 are light that is synthesized coaxially (or nearly coaxially) from pulsed light emitted from the respective light sources of the first light source 181a to the fourth light source 181d.

[0098] [Configuration of Retarder 183] The retarder 183 emits retarder emitted light 183LO, in which the state of pulsed light has been changed, by dividing and combining the retarder incident light 183LI. More specifically, the retarder 183 emits pulsed light with a changed time axis distribution as the first retarder emitted light 183LO1 and the second retarder emitted light 183LO2 to the distribution unit 18B.

[0099] Specifically, the retarder 183 splits the incident pulsed light into multiple (for example, two) pulses, and makes the optical path length of one of the split pulses longer than that of the other pulse, thereby causing a delay in the pulsed light corresponding to the pulse width. The retarder 183 then combines the split pulses to emit pulsed light that has changed state relative to the incident pulsed light. The specific configuration of the retarder 183 will be explained with reference to Figure 11.

[0100] Figure 11 shows an example of the configuration of the retarder 183 of this embodiment. As an example, the figure shows an eight-stage retarder 183 in which nine beam splitters (for example, half prisms) are arranged in series. The retarder 183 comprises an input stage 1831 and a delay stage 1832. The input stage 1831 comprises an input stage beam splitter 1834A.

[0101] The input stage beam splitter 1834A is the first beam splitter to which the pulsed light (retarder incident light 183LI) emitted from the combining unit 182 is incident, among the nine beam splitters described above. The input stage beam splitter 1834A splits the incident pulsed light, sending one portion to the input stage mirror 1835 and the other to the second stage beam splitter. The pulsed light reflected by the input stage mirror 1835 is incident on the second stage beam splitter. In the following description, the optical path passing through the prism mirror (for example, the input stage mirror 1835) is also called a delayed optical path, and the optical path that does not pass through the prism mirror is also called a non-delayed optical path.

[0102] The second-stage beam splitter receives pulsed light emitted from the input stage beam splitter 1834A (i.e., pulsed light that has traveled through the non-delayed optical path and is not delayed) and pulsed light reflected by the input stage mirror 1835 (i.e., pulsed light that has traveled through the delayed optical path and is delayed). In the second-stage beam splitter, the non-delayed pulsed light and the delayed pulsed light are combined and then split into a delayed optical path and a non-delayed optical path.

[0103] As described above, the beam splitter in the retarder 183 combines or splits pulsed light by transmitting a portion of the pulsed light and reflecting the other portion. In other words, the retarder 183 (delay optical system) combines or splits pulsed light by transmitting a portion of the pulsed light and reflecting the other portion.

[0104] Furthermore, a beam splitter (e.g., a half-prism) transmits or reflects pulsed light regardless of the polarization state of the pulsed light (e.g., p-polarization and s-polarization). The retarder 183 combines or splits the pulsed light using the beam splitter. The retarder 183 (delay optical system) splits the pulsed light combined by the combining unit 182 and delays a portion of each of the split pulsed lights. In other words, the retarder 183 (delay optical system) delays a portion of the pulsed light combined by the combining unit 182.

[0105] More specifically, the retarder 183 (delay optical system) changes the temporal characteristics of the pulsed light by splitting a portion of the pulsed light and guiding it into a delay optical path, and then combining the portion of the pulsed light guided into the delay optical path with another portion of the split pulsed light. The retarder 183 (delay optical system) combines pulsed light emitted from multiple light sources, and splits a portion of the combined pulsed light and guides it into a delay optical path.

[0106] By repeatedly splitting and combining pulsed light up to the eighth stage of retarder 183, one pulsed light (see Figure [B]) is converted into 2 to the power of 8 (i.e., 256) group pulsed light (see Figure [C]). In other words, the optical power equivalent to one pulse of the combined pulsed light is realized by multiple consecutive split light (group pulsed light). This makes it possible to suppress the generation of giant pulses.

[0107] The final stage beam splitter 1834B emits retarder emission light 183LO.

[0108] Figure [A] illustrates a retarder 183 in which the first to third stages form a delayed optical path using prism mirrors, and the fourth to eighth stages form a delayed optical path using optical fiber 1835A with relatively high transmittance; however, the retarder is not limited to this. The retarder 183 may be, for example, the retarder shown in Figures 12 to 15 of International Publication No. 2022 / 018810.

[0109] Although the beam synthesis and splitting are described as being performed using a polarized beam splitter, this is not the only method; half-mirrors, half-prisms, etc., may also be used.

[0110] As described in detail above, according to the first embodiment, the light source device 18A includes a wavelength conversion optical element 72a that receives incident light containing light with wavelength λ2 (= 532 nm) and emits outgoing light containing light with a different wavelength λ3 (= 355 nm), and a wavelength conversion optical element 72b that receives incident light containing light with wavelength λ2 (= 532 nm) and emits outgoing light containing light with a different wavelength λ3 (= 355 nm). The light source device 18A includes a combining unit 182 that combines at least a portion of the outgoing light from the wavelength conversion optical element 72a and at least a portion of the outgoing light from the wavelength conversion optical element 72b and emits combined light, and a control device 185 that moves the incident position of the incident light within the incident plane of the wavelength conversion optical element 72a and moves the incident position of the incident light within the incident plane of the wavelength conversion optical element 72b. The control device 185 makes the movement state of incident light on the incident surface of wavelength conversion optical element 72a different from the movement state of incident light on the incident surface of wavelength conversion optical element 72b. This makes it possible to make the timing at which incident light is incident on the moving inflection point on the incident surface of wavelength conversion optical element 72a different from the timing at which incident light is incident on the moving inflection point on the incident surface of wavelength conversion optical element 72b. As a result, fluctuations in the power of the combined light of the emitted light from wavelength conversion optical element 72a and the emitted light from wavelength conversion optical element 72b can be suppressed. Consequently, the quality of the pattern transferred by the spatial light modulator 201 to the exposure target can be improved compared to the case where the timing at which incident light is incident on the moving inflection point on the incident surface of wavelength conversion optical element 72a and the timing at which incident light is incident on the moving inflection point on the incident surface of wavelength conversion optical element 72b coincide.

[0111] In the first embodiment, the control device 185 switches the direction of movement of one incident light on the incident surface of the wavelength conversion optical element 72a from, for example, the -Y1 direction to the +X1 direction, and switches the direction of movement of the incident light on the incident surface of the wavelength conversion optical element 72b from the -Y1 direction to the +X1 direction. The control device 185 makes the timing of switching the direction of movement of one incident light on the incident surface of the wavelength conversion optical element 72a from the -Y1 direction to the +X1 direction different from the timing of switching the direction of movement of the incident light on the incident surface of the wavelength conversion optical element 72b from the -Y1 direction to the +X1 direction, thereby making the movement state of the incident light on the incident surface of the wavelength conversion optical element 72a different from the movement state of the incident light on the incident surface of the wavelength conversion optical element 72b. As a result, the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72a and the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72b can be made different. In the above embodiment, the movement path of the incident light position in the wavelength conversion optical element 72a and the wavelength conversion optical element 72b was the same. However, the movement path of the incident light position in the wavelength conversion optical element 72a and the movement path of the incident light position in the wavelength conversion optical element 72b may be different. In such cases, for example, the control device 185 can be configured to make the timing at which the direction of movement of the incident light at the incident surface of the wavelength conversion optical element 72a switches different from the timing at which the direction of movement of the incident light at the incident surface of the wavelength conversion optical element 72b switches.

[0112] In other words, in the first embodiment, the control device 185 makes the timing at which the direction of movement of the wavelength-converting optical element 72a changes by a predetermined amount or more and the timing at which the direction of movement of the wavelength-converting optical element 72b changes by a predetermined amount or more different, thereby making the movement state of the incident light on the incident surface of the wavelength-converting optical element 72a different from the movement state of the incident light on the incident surface of the wavelength-converting optical element 72b. This makes it possible to make the timing at which the incident light strikes the moving inflection point on the incident surface of the wavelength-converting optical element 72a different from the timing at which the incident light strikes the moving inflection point on the incident surface of the wavelength-converting optical element 72b.

[0113] Furthermore, according to the first embodiment, the light source device 18A includes a drive device 721a that moves the wavelength conversion optical element 72a in a plane direction intersecting the optical axis of the incident light, and a drive device 721b that moves the wavelength conversion optical element 72b in a plane direction intersecting the optical axis of the incident light, and the control device 185 controls the drive devices 721a and 721b. This makes it possible to make the movement state of the incident light on the incident surface of the wavelength conversion optical element 72a different from the movement state of the incident light on the incident surface of the wavelength conversion optical element 72b.

[0114] Furthermore, according to the first embodiment, the drive device 721a drives the wavelength conversion optical element 72a at predetermined timings so that the incident position of the incident light on the wavelength conversion optical element 72a becomes a position where the incident light has not yet been incident, and the drive device 721b drives the wavelength conversion optical element 72b at predetermined timings so that the incident position of the incident light on the wavelength conversion optical element 72b becomes a position where the incident light has not yet been incident. As a result, the wavelength of the incident light can be converted in the undamaged portion, thus maintaining the accuracy of the wavelength conversion.

[0115] In the first embodiment described above, the timing for stepping the wavelength conversion optical element 72a and the timing for stepping the wavelength conversion optical element 72b coincided, but this is not the only option. By making the timing for stepping the region where incident light is incident on the incident surface of the wavelength conversion optical element 72a to another region different from the timing for stepping the region where incident light is incident on the incident surface of the wavelength conversion optical element 72b to another region, the movement state of incident light on the incident surface of the wavelength conversion optical element 72a and the movement state of incident light on the incident surface of the wavelength conversion optical element 72b can be made different.

[0116] Furthermore, in the first embodiment described above, the control device 185 may step-shift the region on the incident surface of the wavelength-converting optical element 72a to which incident light is incident from region R1 to region R2, which is different from region R1, and step-shift the region on the incident surface of the wavelength-converting optical element 72b to which incident light is incident from region R1 to region R2, which is different from region R1, so that the area where region R1 and region R2 overlap on the incident surface of the wavelength-converting optical element 72a is larger than the area where region R1 and region R2 overlap on the incident surface of the wavelength-converting optical element 72b. In other words, the control device 185 makes the speed at which the region on the incident surface of the wavelength-converting optical element 72a to which incident light is incident from region R1 to region R2 smaller than the speed at which the region on the incident surface of the wavelength-converting optical element 72b to which incident light is incident from region R1 to region R2. To put it another way, the distance d1 between the center of region R1 and the center of region R2 on the incident surface of the wavelength conversion optical element 72a is made smaller than the distance d1 between the center of region R1 and the center of region R2 on the incident surface of the wavelength conversion optical element 72b. This makes it possible to make the timing at which the incident light strikes the moving inflection point on the incident surface of the wavelength conversion optical element 72a different from the timing at which the incident light strikes the moving inflection point on the incident surface of the wavelength conversion optical element 72b.

[0117] Furthermore, in the first embodiment described above, the drive device 721a drove the wavelength conversion optical element 72a at a speed V1 so that the incident position of the incident light onto the wavelength conversion optical element 72a moved along the path PTH1, and the drive device 721b drove the wavelength conversion optical element 72b so that the incident position of the incident light onto the wavelength conversion optical element 72b moved along the path PTH1 at a speed V1. In this case, by making the incident position of the incident light on the path PTH1 for the wavelength conversion optical element 72a and the incident position of the incident light on the path PTH1 for the wavelength conversion optical element 72b different at the same time, the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72a and the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72b may be made different. For example, by making the starting point SP of the incident position of the incident light in the wavelength conversion optical element 72a different from the starting point SP of the incident position of the incident light in the wavelength conversion optical element 72b, even when the incident position of the incident light in the wavelength conversion optical element 72a and the incident position of the incident light in the wavelength conversion optical element 72b move along the path PTH1 at the same speed V1, the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72a and the timing at which the incident light is incident on the moving inflection point on the incident surface of the wavelength conversion optical element 72b can be made different.

[0118] Furthermore, in the first embodiment described above, after a predetermined period of time has elapsed, the region in which incident light is incident on the wavelength conversion optical element 72a is moved from region R1 to region R2, and after a predetermined period of time has elapsed, the region in which incident light is incident on the wavelength conversion optical element 72b is moved from region R1 to region R2, but the control device 185 may move the region in which incident light is incident on the wavelength conversion optical element 72a from region R1 to region R2 when the integrated irradiation amount of light emitted from the wavelength conversion optical element 72a, as measured by the monitor 731a, reaches a predetermined amount, and move the region in which incident light is incident on the wavelength conversion optical element 72b from region R1 to region R2 when the integrated irradiation amount of light emitted, as measured by the monitor 731b, reaches a predetermined amount.

[0119] Furthermore, in the first embodiment described above, the control device 185 may set the timing for switching the direction of movement of incident light to the wavelength conversion optical element 72a and the timing for switching the direction of movement of incident light to the wavelength conversion optical element 72b to be different from the period during which the object to be exposed is irradiated with the composite pulse light. That is, during the period during which the object to be exposed is irradiated with the composite pulse light, the control device 185 may refrain from switching the direction of movement of incident light to the wavelength conversion optical element 72a and the direction of movement of incident light to the wavelength conversion optical element 72b. This makes it possible to suppress fluctuations in the power of the composite pulse light during the period during which the object to be exposed is irradiated with the composite pulse light, thereby improving the accuracy of the pattern transferred to the object to be exposed.

[0120] Furthermore, in the first embodiment, the timing for switching the direction of the incident light to the wavelength conversion optical element 72a may be set to occur within the period for processing the substrate held on the stage 14, or the timing for switching the direction of the incident light to the wavelength conversion optical element 72a may be set to occur within the period for processing another substrate held on the stage 14. This reduces fluctuations in the power of the combined pulsed light during processing of each substrate, thereby improving the accuracy of the pattern transferred to the substrate.

[0121] Furthermore, in the first embodiment described above, the drive device 721a may not change the direction of movement of the wavelength conversion optical element 72a by a predetermined amount while projecting patterned light from the spatial light modulator 201 onto the object to be exposed (e.g., a substrate), and the drive device 721b may not change the direction of movement of the wavelength conversion optical element 72a by a predetermined amount while projecting patterned light from the spatial light modulator 201 onto the object to be exposed (e.g., a substrate). This reduces fluctuations in the power of the composite pulsed light while projecting patterned light onto the object to be exposed, thereby improving the accuracy of the pattern transferred to the object to be exposed.

[0122] 《Second Embodiment》 In the first embodiment described above, the incident position of the incident light was moved along a moving path having a moving inflection point, but the embodiment is not limited to this. In the second embodiment, the moving path of the incident position of the incident light is a moving path without a moving inflection point, thereby suppressing fluctuations in the power of the pulsed light emitted by the wavelength conversion optical element 72.

[0123] Figure 12 shows an example of the movement path of the incident position of incident light to the wavelength conversion optical element 72 in the second embodiment. In the second embodiment, the drive device 721 moves the wavelength conversion optical element 72 so that the incident position of the incident light moves along the path PTH2 from the starting point SP to the ending point EP, as indicated by the arrow AR21.

[0124] As shown in Figure 12, the travel path PTH2 is a curved path with changing curvature, specifically a spiral path. In other words, the travel path PTH2 is a curved path where the curvature gradually decreases from the starting point SP to the ending point EP. Note that the starting point SP and the ending point EP can be reversed. In this case, the travel path PTH2 can be said to be a curved path where the curvature gradually increases from the starting point SP to the ending point EP.

[0125] In this way, by making the movement path PTH2 a spiral path, it is possible to prevent the occurrence of movement inflection points, thereby suppressing fluctuations in the illuminance (power) of the pulsed light emitted from the wavelength conversion optical element 72. As a result, when pulsed light from the first light source unit 181a to the eighth light source unit 181h is combined, fluctuations in the power of the combined pulsed light can be suppressed.

[0126] In the first and second embodiments described above, the incident position of the incident light on the wavelength-converting optical element 72 was adjusted by moving the wavelength-converting optical element 72 with the drive device 721, but this is not the only method. For example, an optical system for adjusting the optical path of the incident light on the wavelength-converting optical element 72 may be provided in each of the first to eighth light sources 181a to 181h, and the drive device 721 may adjust the incident position of the incident light on the incident surface of the wavelength-converting optical element 72 by controlling the optical system instead of the wavelength-converting optical element 72. In this case, the control device 185 controls the incident position of the synthesized pulsed light on the substrate irradiated with the synthesized pulsed light, based on the incident position of the incident light on the wavelength-converting optical element 72 in each of the first to eighth light sources 181a to 181h.

[0127] The embodiments described above are preferred examples of the present invention. However, the invention is not limited thereto, and various modifications are possible without departing from the spirit of the invention.

[0128] 1 Exposure apparatus 14 Stage 16 Illumination module 17 Projection module 18A Light source device 50 Light source unit 201 Spatial light modulator 72, 72a-72h Wavelength conversion optical element 182 Synthesis unit 183 Retarder 185 Control device

Claims

1. An optical apparatus comprising: a first wavelength-converting optical element that receives first incident light containing light having a first wavelength and emits first output light containing light having a second wavelength different from the first wavelength; a second wavelength-converting optical element that receives second incident light containing light having a third wavelength and emits second output light containing light having a fourth wavelength different from the third wavelength; a combining device that combines at least a portion of the first output light and at least a portion of the second output light and emits combined light; and a control device that moves the incident position of the first incident light within the incident plane of the first wavelength-converting optical element and moves the incident position of the second incident light within the incident plane of the second wavelength-converting optical element, wherein the control device causes the movement state of the first incident light on the incident plane of the first wavelength-converting optical element to be different from the movement state of the second incident light on the incident plane of the second wavelength-converting optical element.

2. The optical apparatus according to claim 1, wherein the control device switches the direction of movement of the first incident light at the incident surface of the first wavelength conversion optical element from a first direction to a second direction, switches the direction of movement of the second incident light at the incident surface of the second wavelength conversion optical element from a third direction to a fourth direction, and the timing of the switching from the first direction to the second direction and the timing of the switching from the third direction to the fourth direction are different for the movement state of the first incident light and the movement state of the second incident light.

3. The optical apparatus according to claim 1, wherein the movement state of the first incident light and the movement state of the second incident light are made different, including making the timing at which the movement direction of the first wavelength conversion optical element changes by a predetermined amount or more different from the timing at which the movement direction of the second wavelength conversion optical element changes by a predetermined amount or more.

4. The optical apparatus according to claim 1, wherein the control device moves the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident in a step-by-step manner to a plurality of regions, and moves the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident in a step-by-step manner to a plurality of regions, and the difference between the movement state of the first incident light and the movement state of the second incident light is made different between the timing of moving the region on which the first incident light is incident in a step-by-step manner to a plurality of regions and the timing of moving the region on which the second incident light is incident in a step-by-step manner to a plurality of regions.

5. The optical apparatus according to claim 1, wherein the control device steps the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident, from a first region of the incident surface to a second region of the incident surface that is different from the first region, and steps the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident, from a third region of the incident surface to a fourth region of the incident surface that is different from the third region, and the difference between the movement state of the first incident light and the movement state of the second incident light is made larger than the overlapping area of ​​the third region and the fourth region.

6. The optical apparatus according to claim 1, wherein the control device moves the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident from a first region of the incident surface to a second region of the incident surface that is different from the first region, and moves the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident from a third region of the incident surface to a fourth region of the incident surface that is different from the third region, and the movement state of the first incident light and the movement state of the second incident light are different, by making the speed at which the region on which the first incident light is incident from the first region to the second region smaller than the speed at which the region on which the second incident light is incident from the third region to the fourth region.

7. The optical apparatus according to claim 1, wherein the control device moves the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident in a step from a first region of the incident surface to a second region of the incident surface that is different from the first region, and moves the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident in a step from a third region of the incident surface to a fourth region of the incident surface that is different from the third region, and the movement state of the first incident light and the movement state of the second incident light are made different by making the distance between the center of the first region and the center of the second region smaller than the distance between the center of the third region and the center of the fourth region.

8. The optical apparatus according to any one of claims 5 to 7, wherein the power fluctuation of the first emitted light when the region into which the first incident light is incident is moved from the first region to the second region is greater than the power fluctuation of the second emitted light when the region into which the second incident light is incident is moved from the third region to the fourth region.

9. An optical apparatus according to any one of claims 1 to 8, comprising: a first drive device for moving the first wavelength conversion optical element in a plane direction intersecting the optical axis of the first incident light; and a second drive device for moving the second wavelength conversion optical element in a plane direction intersecting the optical axis of the second incident light, wherein the control device controls the first drive device and the second drive device.

10. The optical apparatus according to claim 9, wherein the first drive device drives the first wavelength conversion optical element in a plane perpendicular to the optical axis of the first incident light, and the second drive device drives the second wavelength conversion optical element in a plane perpendicular to the optical axis of the second incident light.

11. The optical apparatus according to claim 9 or 10, wherein the first drive device drives the first wavelength conversion optical element at predetermined intervals such that the incident position of the first incident light to the first wavelength conversion optical element is a position where the first incident light has not yet been incident, and the second drive device drives the second wavelength conversion optical element at predetermined intervals such that the incident position of the second incident light to the second wavelength conversion optical element is a position where the second incident light has not yet been incident.

12. The optical apparatus according to claim 9 or 10, wherein the first drive device drives the first wavelength-converting optical element at a first velocity such that the incident position of the first incident light onto the first wavelength-converting optical element moves along a first path, and the second drive device drives the second wavelength-converting optical element at a first velocity such that the incident position of the second incident light onto the second wavelength-converting optical element moves along a second path which is the same as the first path, causing the incident position of the first incident light on the first path at a first time point to be different from the incident position of the second incident light on the second path at a first time point.

13. An optical apparatus according to any one of claims 1 to 8, comprising: a first optical system for adjusting the optical path of the first incident light; and a second optical system for adjusting the optical path of the second incident light, wherein the control device controls the first optical system to adjust the incident position of the first incident light on the incident surface of the first wavelength conversion optical element; controls the second optical system to adjust the incident position of the second incident light on the incident surface of the second wavelength conversion optical element; and controls the incident position of the composite light on an object irradiated with the composite light based on the incident position of the first incident light and the incident position of the second incident light.

14. The optical apparatus according to claim 2, wherein the control device moves the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident in the first direction from a first region of the incident surface to a second region of the incident surface which includes a region overlapping with the first region and is different from the first region, and moves the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident in the third direction from a third region of the incident surface to a fourth region of the incident surface which includes a region overlapping with the third region and is different from the third region.

15. The optical apparatus according to claim 14, wherein the control device moves the region on the incident surface of the first wavelength conversion optical element to which the first incident light is incident from the second region to a fifth region of the incident surface, which includes a region overlapping with the first and second regions and is different from the first and second regions, in the second direction, and moves the region on the incident surface of the second wavelength conversion optical element to which the second incident light is incident from the fourth region to a sixth region of the incident surface, which includes a region overlapping with the third and fourth regions and is different from the third and fourth regions, in the fourth direction.

16. The optical apparatus according to claim 14 or 15, wherein the control device moves the region into which the first incident light is incident from the first region to the second region after a predetermined period of time has elapsed, and moves the region into which the second incident light is incident from the third region to the fourth region after a predetermined period of time has elapsed.

17. The optical apparatus according to claim 14 or claim 15, comprising: a first monitor for monitoring the first emitted light; and a second monitor for monitoring the second emitted light, wherein the control device moves the region into which the first incident light is incident from the first region to the second region when the cumulative irradiation amount of the first emitted light measured by the first monitor reaches a predetermined amount; and moves the region into which the second incident light is incident from the third region to the fourth region when the cumulative irradiation amount of the second emitted light measured by the second monitor reaches a predetermined amount.

18. The optical apparatus according to any one of claims 1 to 17, wherein the first incident light is light transmitted through a third wavelength-converting optical element, and the second incident light is light transmitted through a fourth wavelength-converting optical element.

19. An optical apparatus according to any one of claims 1 to 18, comprising: a first light source unit that generates the first incident light which is pulsed light; and a second light source unit that generates the second incident light which is pulsed light.

20. The optical apparatus according to claim 19, wherein the first light source and the second light source each generate the first incident light and the second incident light, respectively, so that their light emission timings are synchronized.

21. The optical device according to claim 19 or claim 20, wherein the optical power equivalent to one pulse of the composite light, calculated from the first frequency at which the composite light oscillates and the optical output of the composite light, is realized by a plurality of consecutive split beams.

22. An optical device comprising: a first wavelength conversion optical element into which first incident light containing light having a first wavelength is incident and which emits first outgoing light containing light having a second wavelength different from the first wavelength; and a control device for moving the incident position of the first incident light within the incident plane of the first wavelength conversion optical element along a first path, wherein the first path is a curved path.

23. The optical apparatus according to claim 22, wherein the first path is a curved path with changing curvature.

24. The optical apparatus according to claim 22, wherein the first path is a curved path in which the curvature gradually decreases or gradually increases.

25. The optical apparatus according to claim 22, wherein the first path is a spiral path.

26. The optical apparatus according to claim 22, comprising: a second wavelength-converting optical element to which a second incident light containing a third wavelength is incident and which emits a second outgoing light containing a fourth wavelength different from the third wavelength; and a combining device that combines at least a portion of the first outgoing light and at least a portion of the second outgoing light and emits combined light, wherein the control device moves the incident position of the second incident light within the incident plane of the second wavelength-converting optical element along a second path, and the second path is a curved path.

27. The optical apparatus according to claim 26, wherein the first path is a curved path with changing curvature, and the second path is a curved path with changing curvature.

28. The optical apparatus according to claim 26, wherein the first path is a curved path in which the curvature gradually decreases or gradually increases, and the second path is a curved path in which the curvature gradually decreases or gradually increases.

29. The optical apparatus according to claim 26, wherein the first path is a spiral path, and the second path is a spiral path.

30. An exposure apparatus comprising: an optical device according to any one of claims 1 to 29; and a stage for holding an object to be irradiated by light emitted from the optical device.

31. An exposure apparatus comprising: an optical apparatus according to claim 2 and any one of claims 14 to 17; and a stage for holding an object to be irradiated with emitted light emitted from the optical apparatus, wherein at least one of the timing of switching from the first direction to the second direction and the timing of switching from the third direction to the fourth direction is within a period different from the period during which the object is irradiated with the composite light.

32. The exposure apparatus according to claim 31, wherein the timing of switching from the first direction to the second direction is within the period during which the first substrate held on the stage is processed, and the timing of switching from the third direction to the fourth direction is within the period during which the second substrate held on the stage is processed.

33. A processing apparatus comprising: an optical apparatus according to any one of claims 1 to 29; a patterning apparatus for patterning the emitted light emitted from the optical apparatus; and a projection system for projecting the patterned light onto a workpiece, wherein the patterning apparatus patterns the emitted light in synchronization with the emission timing of the emitted light emitted from the optical apparatus.

34. A processing apparatus comprising: an optical device according to any one of claims 10 to 12; a patterning device for patterning emitted light emitted from the optical device; and a projection system for projecting the patterned light onto a workpiece, wherein the patterning device patterns the emitted light in synchronization with the emission timing of the emitted light emitted from the optical device; the first drive device does not change the direction of movement of the first wavelength conversion optical element by more than a predetermined amount while projecting the patterned light onto the workpiece; and the second drive device does not change the direction of movement of the second wavelength conversion optical element by more than a predetermined amount while projecting the patterned light onto the workpiece.

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