Method of manufacturing laser devices and electronic devices

Abstract

The laser device has a grating system, an actuator system that adjusts a first incidence angle of a first portion of a light beam with respect to the grating system and a second incidence angle of a second portion of the light beam with respect to the grating system, and a processor that controls the actuator system, whereby the first and second incidence angles are periodically varied in a manner at least one of in phase and in a range of variation.

Description

Technical Field

[0001] This disclosure relates to methods for manufacturing laser devices and electronic components. Background Technology

[0002] In recent years, with the miniaturization and high integration of semiconductor integrated circuits, there has been a demand for higher resolution in semiconductor exposure equipment. Therefore, the use of shorter wavelengths of light emitted from exposure light sources has been developed. For example, as gas laser devices for exposure, there are KrF excimer lasers that use lasers with an output wavelength of approximately 248 nm, and ArF excimer lasers that use lasers with an output wavelength of approximately 193 nm.

[0003] The natural oscillating light from KrF and ArF excimer lasers has a relatively wide spectral linewidth, approximately 350–400 pm. Therefore, when using projection lenses made of materials that allow ultraviolet light to pass through KrF and ArF lasers, chromatic aberration sometimes occurs. As a result, resolution may be reduced. Therefore, it is necessary to narrow the spectral linewidth of the laser output from the gas laser device to a level that eliminates chromatic aberration. Thus, in the laser resonator of a gas laser device, a line-narrowing module (LNM) containing narrowing elements (etalon, grating, etc.) is sometimes included to achieve this narrowing. Hereinafter, gas laser devices with narrowed spectral linewidths will be referred to as narrow-bandgap gas laser devices.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: U.S. Patent Application Publication No. 2005 / 0083983 Summary of the Invention

[0007] One aspect of the laser device disclosed herein includes: a grating system; an actuator system that adjusts a first portion of a beam incident on the grating system at a first incident angle relative to the grating system and a second portion of the beam at a second incident angle relative to the grating system; and a processor that controls the actuator system such that the first and second incident angles are periodically varied in a manner different from at least one of phase and variation range.

[0008] One aspect of the present disclosure discloses a method for manufacturing an electronic device comprising the steps of: generating a laser using a laser device, outputting the laser to an exposure device, and exposing the laser on a photosensitive substrate within the exposure device to manufacture the electronic device. The laser device comprises: a grating system; an actuator system that adjusts a first portion of a beam incident on the grating system at a first incident angle relative to the grating system and a second portion of the beam at a second incident angle relative to the grating system; and a processor that controls the actuator system such that the first and second incident angles are periodically varied in a manner different from at least one of phase and variation range. Attached Figure Description

[0009] Hereinafter, several embodiments of the present disclosure will be described as simple examples with reference to the accompanying drawings.

[0010] Figure 1 The structure of the exposure system in the comparative example is shown in outline.

[0011] Figure 2 The structure of the laser device in the comparative example is shown in general.

[0012] Figure 3 This shows how the position of the scanned field of the irradiated object changes relative to the position of the pulsed laser.

[0013] Figure 4 This shows how the position of the scanned field of the irradiated object changes relative to the position of the pulsed laser.

[0014] Figure 5 This shows how the position of the scanned field of the irradiated object changes relative to the position of the pulsed laser.

[0015] Figure 6 This is a graph showing an example of the drive voltage of the rotary table in the comparative example.

[0016] Figure 7 Showing will Figure 6 The diagram shows the ideal cumulative spectrum waveform for one cycle when the driving voltage is applied to the rotary table.

[0017] Figure 8 This is a graph showing the change in the incident angle of the light beam incident on the grating in the first example of the comparative example.

[0018] Figure 9 The incident angle of the light beam incident on the grating is shown as follows: Figure 8 The cumulative spectrum waveform under the condition shown.

[0019] Figure 10 This is a graph showing the change in the incident angle of the light beam incident on the grating in the comparative example.

[0020] Figure 11 The incident angle of the light beam incident on the grating is shown as follows: Figure 10 The cumulative spectrum waveform under the condition shown.

[0021] Figure 12 The structure of the laser device of the first embodiment is shown in a schematic diagram.

[0022] Figure 13 It is a stereoscopic view of the first and second mirrors.

[0023] Figure 14 This is a graph showing an example of the drive voltage applied to the rotary table in the first embodiment.

[0024] Figure 15 Showing will Figure 14 The cumulative spectrum waveform for half a cycle is shown when the driving voltage is applied to the rotary table.

[0025] Figure 16 This is a graph showing a variation of the driving voltage applied to the rotary table in the first embodiment.

[0026] Figure 17 This is a flowchart illustrating the process of setting the start voltage and end voltage in the first embodiment.

[0027] Figure 18 This is a graph illustrating an example of the driving voltage applied to the rotary table in the second embodiment.

[0028] Figure 19 This is a graph illustrating an example of the driving voltage applied to the rotary table in the second embodiment.

[0029] Figure 20 This is a graph illustrating an example of the driving voltage applied to the rotary table in the second embodiment.

[0030] Figure 21 This is a graph showing an example of the first incident angle and the second incident angle of the first part and the second part of the grating in the second embodiment.

[0031] Figure 22 This is a flowchart illustrating the process of setting the first start voltage, the first end voltage, the second start voltage, and the second end voltage in the second embodiment.

[0032] Figure 23 This is a graph showing a modified example of the first and second incident angles in the second embodiment.

[0033] Figure 24 An example of the cumulative spectrum waveform for one cycle in the second embodiment is shown.

[0034] Figure 25A variation of the cumulative spectrum waveform for one cycle in the second embodiment is shown.

[0035] Figure 26 The structure of the laser device according to the third embodiment is shown in outline.

[0036] Figure 27 It is a three-dimensional image of a prism.

[0037] Figure 28 This is a side view of a prism.

[0038] Figure 29 The structure of the laser device according to the fourth embodiment is shown in outline.

[0039] Figure 30 This is a stereoscopic view of the first and second gratings.

[0040] Figure 31 This is a graph illustrating an example of the drive voltage applied to the rotary table in the fifth embodiment.

[0041] Figure 32 Showing will Figure 31 The cumulative spectrum waveform for half a cycle is shown when the driving voltage is applied to the rotary table. Detailed Implementation

[0042] <Content>

[0043] 1. Comparative Example

[0044] 1.1 Exposure System

[0045] 1.1.1 Structure of Exposure Device 200

[0046] 1.1.2 Actions

[0047] 1.2 Laser device 100

[0048] 1.2.1 Structure

[0049] 1.2.2 Actions

[0050] 1.3 Narrowband Module 14

[0051] 1.3.1 Structure

[0052] 1.3.2 Actions

[0053] 1.4 Number of irradiation pulses N

[0054] 1.5 Examples of periodic wavelength changes

[0055] 1.6 Comparative Examples

[0056] 2. A laser device 100a with different phases at the first and second incident angles α1 and α2.

[0057] 2.1 Structure

[0058] 2.2 Actions

[0059] 2.3 Function

[0060] 3. Laser device 100a with different ranges of variation for the first and second incident angles α1 and α2.

[0061] 3.1 Structure and Action

[0062] 3.2 Function

[0063] 4. A laser device 100c that adjusts the first and second incident angles α1 and α2 according to the rotation angles θ1 and θ2 of prisms 44 and 45.

[0064] 4.1 Structure and Action

[0065] 4.2 Function

[0066] 5. A laser device 100d that adjusts the first and second incident angles α1 and α2 according to the rotation angles θ1 and θ2 of the first and second gratings 51 and 52.

[0067] 5.1 Structure and Action

[0068] 5.2 Function

[0069] 6. A laser device 100a that causes the first and second incident angles α1 and α2 to vary in a sinusoidal pattern.

[0070] 6.1 Structure and Action

[0071] 6.2 Function

[0072] 7. Other

[0073] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. The embodiments described below illustrate several examples of this disclosure and do not limit its scope. Furthermore, the structures and operations described in each embodiment are not necessarily all necessary for the structures and operations of this disclosure. Additionally, the same reference numerals are used to denote the same structural elements, and repeated descriptions are omitted.

[0074] 1. Comparative Example

[0075] 1.1 Exposure System

[0076] Figure 1 The structure of the exposure system in the comparative example is shown in outline. The comparative examples disclosed herein are methods known only to the applicant and are not publicly known examples acknowledged by the applicant.

[0077] The exposure system includes a laser device 100 and an exposure device 200. Figure 1 The laser device 100 is shown in a simplified form.

[0078] The laser device 100 is configured to generate pulsed laser light and output it toward the exposure apparatus 200. The laser device 100 includes a laser control processor 130. The laser control processor 130 is a processing device that includes a memory 132 storing a control program and a CPU (central processing unit) 131 that executes the control program. The laser control processor 130 is specifically configured or programmed to perform the various processes included in this disclosure.

[0079] 1.1.1 Structure of Exposure Device 200

[0080] like Figure 1 As shown, the exposure apparatus 200 includes an illumination optics system 201, a projection optics system 202, and an exposure control processor 210.

[0081] The illumination optical system 201 illuminates a mask pattern (not shown) disposed on a mask stage RT using a pulsed laser incident from the laser device 100.

[0082] The projection optics system 202 projects a reduced image of the pulsed laser light passing through the mask onto a workpiece (not shown) positioned on the workpiece stage WT. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with a resist film.

[0083] The exposure control processor 210 is a processing device that includes a memory 212 storing a control program and a CPU 211 executing the control program. The exposure control processor 210 is specifically configured or programmed to perform the various processes contained in this disclosure.

[0084] 1.1.2 Actions

[0085] Exposure control processor 210 sends data including the number of irradiation pulses N, the cumulative spectrum center wavelength λ0, and the wavelength range Δλ, as well as a trigger signal, to laser control processor 130. Laser control processor 130 controls laser device 100 according to the data and signals received from exposure control processor 210.

[0086] The exposure control processor 210 synchronously moves the mask stage RT and the workpiece stage WT in opposite parallel directions. This exposes the workpiece using pulsed laser light reflecting the mask pattern.

[0087] This exposure process transfers a photomask pattern onto a semiconductor wafer. Electronic devices can then be manufactured through multiple processes.

[0088] 1.2 Laser device 100

[0089] 1.2.1 Structure

[0090] Figure 2 The structure of the laser device 100 in the comparative example is shown in outline. Figure 2 The diagram shows the V-axis, H-axis, and Z-axis, which are perpendicular to each other. Figure 2 The laser device 100 is shown as observed in the -V direction.

[0091] In addition to the laser control processor 130, the laser device 100 also includes a laser cavity 10, a pulsed power module (PPM) 13, a narrowband module 14, and an output coupling mirror 15. The narrowband module 14 and the output coupling mirror 15 constitute an optical resonator.

[0092] The laser cavity 10 is positioned in the optical path of the optical resonator. Windows 10a and 10b are provided in the laser cavity 10.

[0093] A discharge electrode 11a and a pair of discharge electrodes (not shown) are disposed inside the laser cavity 10. The discharge electrodes (not shown) are located at a position overlapping with the discharge electrode 11a in the V-axis direction. A laser gas is sealed in the laser cavity 10, which includes, for example, argon or krypton as a rare gas, fluorine as a halogen gas, neon as a buffer gas, etc.

[0094] The pulse power module 13 includes a switch (not shown) and is connected to a charger (not shown).

[0095] The narrowband module 14 includes prisms 41-43, mirror 63, and grating 53. Details of the narrowband module 14 will be described later.

[0096] The output coupling mirror 15 is composed of partial reflectors.

[0097] 1.2.2 Actions

[0098] The laser control processor 130 receives data from the exposure control processor 210, including the number of irradiation pulses N, the cumulative spectral center wavelength λ0, and the wavelength range Δλ. This data can also be received from a lithography control device (not shown), which is different from the exposure apparatus 200. The lithography control device can also control multiple exposure apparatuses 200.

[0099] The laser control processor 130 calculates the start wavelength λs and the end wavelength λe based on the center wavelength λ0 of the accumulated spectrum and the wavelength range Δλ. The start wavelength λs is obtained by subtracting half of the wavelength range Δλ from the center wavelength λ0 of the accumulated spectrum. The end wavelength λe is obtained by adding half of the wavelength range Δλ to the center wavelength λ0 of the accumulated spectrum. The laser control processor 130 sends a control signal to the narrowband module 14 based on the start wavelength λs and the end wavelength λe.

[0100] The laser control processor 130 receives a trigger signal from the exposure control processor 210. The laser control processor 130 sends an oscillation trigger signal based on the trigger signal to the pulse power module 13. After receiving the oscillation trigger signal from the laser control processor 130, a switch included in the pulse power module 13 is turned on. After the switch is turned on, the pulse power module 13 generates a pulsed high voltage based on the electrical energy charged by the charger and applies this high voltage to the discharge electrode 11a.

[0101] After a high voltage is applied to the discharge electrode 11a, a discharge is generated inside the laser cavity 10. The energy from this discharge excites the laser gas inside the laser cavity 10 to transition to a higher energy level. Then, when the excited laser gas transitions to a lower energy level, it emits light of a wavelength corresponding to the energy level difference.

[0102] Light generated inside the laser cavity 10 is emitted to the outside of the laser cavity 10 through windows 10a and 10b. The light emitted from window 10a is incident as beam 90 onto the narrowband module 14. Light near the desired wavelength in the beam 90 incident on the narrowband module 14 returns from the narrowband module 14 to the laser cavity 10.

[0103] The output coupling mirror 15 allows a portion of the light emitted from the window 10b to pass through and be output, while the other portion is reflected back to the laser cavity 10.

[0104] Thus, the light emitted from the laser cavity 10 oscillates between the narrowing module 14 and the output coupling mirror 15. This light is amplified each time it passes through the discharge space inside the laser cavity 10. Furthermore, each time the light is refracted back by the narrowing module 14, it is narrowed, becoming light with a sharp wavelength distribution, which takes a portion of the range of wavelengths selected by the narrowing module 14 as the center wavelength of the pulse spectrum. The narrowed light, thus undergoing laser oscillation, is output as a pulsed laser from the output coupling mirror 15.

[0105] Pulsed laser light output from laser device 100 is incident on exposure device 200.

[0106] 1.3 Narrowband Module 14

[0107] 1.3.1 Structure

[0108] Prisms 41, 42, and 43 are arranged in this order along the optical path of the beam 90 exiting from window 10a. Prisms 41 to 43 are configured such that the surfaces of prisms 41 to 43, which are for the incident and exit points of the beam 90, are all parallel to the V-axis and are supported by cages (not shown).

[0109] Mirror 63 is positioned in the optical path of the beam 90 that passes through prisms 41-43. Mirror 63 is configured such that the surface reflecting the beam 90 is parallel to the V-axis, and mirror 63 is rotatable about an axis parallel to the V-axis via a rotary table 163. As an example of the rotary table 163, a highly responsive rotary table that rotates via a piezoelectric element is provided.

[0110] The grating 53 is positioned in the optical path of the beam 90 after it is reflected by the mirror 63. The direction of the groove of the grating 53 is parallel to the V-axis.

[0111] The grating 53 is supported by a cage (not shown).

[0112] 1.3.2 Actions

[0113] The beam 90 emitted from window 10a changes its direction of travel in a plane parallel to the HZ plane, which is perpendicular to the V-axis, by passing through prisms 41 to 43 respectively, thereby widening the beam width in the plane parallel to the HZ plane.

[0114] The light beam 90, after passing through prisms 41-43, is reflected by mirror 63 and enters the grating 53.

[0115] The light beam 90 incident on the grating 53 is reflected by multiple slots of the grating 53 and diffracted in a direction corresponding to the wavelength of the light. The grating 53 is configured in a Littert configuration so that the incident angle α of the light beam 90 incident on the grating 53 from the mirror 63 coincides with the diffraction angle of the diffracted light of the desired wavelength.

[0116] Mirror 63 and prisms 41-43 reduce the beam width of the light returning from grating 53 in a plane parallel to the HZ plane, and cause the light to return to the interior of laser cavity 10 via window 10a.

[0117] The laser control processor 130 controls the rotary stage 163 via a driver (not shown). The rotation angle θ of the mirror 63 changes according to the driving voltage V applied to the rotary stage 163 from the driver. Depending on the rotation angle θ, the incident angle α of the beam 90 incident on the grating 53 changes between the initial incident angle αs and the final incident angle αe, and the wavelength λ selected by the narrowing module 14 changes.

[0118] The relationship between the rotation angle θ and the driving voltage V is given by the equation θ = g(V). For example, the larger the driving voltage V, the larger the rotation angle θ. The relationship between the wavelength λ and the rotation angle θ is given by the equation λ = f(θ). For example, the larger the rotation angle θ, the larger the incident angle α, and the larger the wavelength λ.

[0119] The laser control processor 130 controls the rotary stage 163 pulse by pulse according to the cumulative spectrum center wavelength λ0 and wavelength range Δλ received from the exposure control processor 210, so that the orientation of the mirror 63 changes periodically with multiple pulses. Thus, the pulse spectrum center wavelength changes in multiple stages within the wavelength range Δλ centered on the cumulative spectrum center wavelength λ0, changing periodically with multiple pulses. In this way, the laser device 100 changes the pulse spectrum center wavelength with multiple pulses, thereby enabling multi-wavelength oscillation.

[0120] Exposure apparatus 200 (reference) Figure 1 The focal length in the image depends on the wavelength of the pulsed laser. A pulsed laser that oscillates at multiple wavelengths and is incident on the exposure apparatus 200 can image at multiple different positions along the optical path axis of the pulsed laser, thus substantially increasing the depth of focus. For example, when exposing a thick resist film, imaging performance in the thickness direction of the resist film can be maintained.

[0121] 1.4 Number of irradiation pulses N

[0122] Figures 3-5 This illustrates how the position of the scanning field SF of the irradiated object changes relative to the position of the pulsed laser. The irradiated object is, for example, a semiconductor wafer. The scanning field SF of the semiconductor wafer corresponds, for example, to a region where several semiconductor chips are formed among a plurality of semiconductor chips formed on the semiconductor wafer. A photoresist film is coated on the scanning field SF. The width of the scanning field SF in the X-axis direction is the same as the width of the pulsed laser beam cross-section B in the X-axis direction at the position of the irradiated object. The width of the scanning field SF in the Y-axis direction is larger than the width W of the pulsed laser beam cross-section B in the Y-axis direction at the position of the irradiated object.

[0123] according to Figure 3 , Figure 4 , Figure 5 The steps of exposing the scanning field SF to pulsed laser light are performed sequentially. First, as... Figure 3 As shown, the workpiece stage WT is positioned such that the +Y direction end SFy+ of the scanning field SF is separated by a predetermined distance in the -Y direction from the -Y direction end By- of the beam cross-section B. Then, the workpiece stage WT is accelerated in the +Y direction to a velocity Vy before the +Y direction end SFy+ of the scanning field SF aligns with the -Y direction end By- of the beam cross-section B. Figure 4 As shown, the workpiece stage WT is moved so that the position of the scanning field SF moves at a constant velocity Vy relative to the position of the beam section B. Figure 5As shown, the workpiece stage WT is moved until the end of the scanning field SF in the -Y direction, SFy-, passes through the end of the beam section B in the +Y direction, By+. Then, the exposure of the scanning field SF ends. In this way, exposure is performed while the position of the scanning field SF relative to the beam section B is moved.

[0124] The time T required to move the scanning field SF at a speed Vy by a distance equivalent to the width W of the beam cross section B of the pulsed laser is as follows.

[0125] T = W / Vy……Equation 1

[0126] The number of pulses N of the pulsed laser irradiating any part of the scanning field SF is the same as the number of pulses of the pulsed laser generated in the required time T, as described below.

[0127] N = F·T……Equation 2

[0128] Here, F is the repetition frequency of the pulsed laser.

[0129] The number of irradiation pulses N is also called the N-interval pulse number.

[0130] 1.5 Examples of periodic wavelength changes

[0131] Figure 6 This is a graph illustrating an example of the drive voltage V of the rotary table 163 in the comparative example. Figure 6 In the diagram, the horizontal axis represents time t, and the vertical axis represents the driving voltage V.

[0132] exist Figure 6 In the example shown, the driving voltage V varies periodically between the start voltage Vs and the end voltage Ve. The start voltage Vs is the driving voltage corresponding to the start wavelength λs, and the end voltage Ve is the driving voltage corresponding to the end wavelength λe. Figure 6 The small circles shown represent the output timing of the pulsed laser and the driving voltage V at that time. The driving voltage V changes with a constant voltage displacement ΔV for each pulse. The driving voltage V is varied with a period of time N / F, obtained by multiplying the repetition period 1 / F of the pulsed laser by the number of irradiation pulses N. According to Equation 2 above, the time N / F is equal to the required time T. By varying the driving voltage V with the required time T as the variation period, the moving cumulative spectrum waveform remains constant in any part of the scanning field SF of the irradiated object.

[0133] Figure 7 Showing will Figure 6 The diagram shows the ideal cumulative spectrum waveform for one cycle when the driving voltage V is applied to the rotary stage 163. Figure 7 In the diagram, the horizontal axis represents wavelength λ, and the vertical axis represents light intensity I. For example... Figure 6As shown, the driving voltage V is varied in multiple stages between the starting voltage Vs and the ending voltage Ve, thereby... Figure 7 The cumulative spectral waveform shown is a flat-topped spectral waveform with approximately uniform light intensity I between the start wavelength λs and the end wavelength λe.

[0134] The variation of the driving voltage V is not limited to Figure 6 The triangular wave shape shown can also be a sawtooth wave shape.

[0135] 1.6 Comparative Examples

[0136] Figure 8 This is a graph showing the first example of the variation in the incident angle α of the beam 90 incident on the grating 53 in the comparative example. The incident angle α of the beam 90 incident on the grating 53 varies according to the driving voltage V applied to the rotary stage 163. However, when the angular velocity of the mirror 63 based on the rotary stage 163 is insufficient, the incident angle α sometimes does not reach the ideal starting incident angle αs0 corresponding to the starting voltage Vs and the ideal ending incident angle αe0 corresponding to the ending voltage Ve. For example, sometimes the incident angle α varies between the starting incident angle αs and the ending incident angle αe.

[0137] Figure 9 The incident angle α of the beam 90 incident on the grating 53 is shown as follows: Figure 8 The cumulative spectrum waveform under the condition shown is as follows. When the angular velocity of mirror 63 is insufficient, the center wavelength of the pulse spectrum will not reach the ideal start wavelength λs0 and end wavelength λe0, but will vary between the start wavelength λs and the end wavelength λe. Therefore, sometimes the wavelength range Δλ required by the exposure device 200 cannot be achieved.

[0138] Figure 10 This is a graph showing the change in the incident angle α of the beam 90 incident on the grating 53 in the comparative example. When the angular acceleration of the mirror 63 based on the rotary stage 163 is insufficient, the rotation of the mirror 63 sometimes slows down immediately after the rotation direction is switched.

[0139] Figure 11 The incident angle α of the beam 90 incident on the grating 53 is shown as follows: Figure 10 The cumulative spectrum waveform under the conditions shown is as described. When the angular acceleration of mirror 63 is insufficient, the center wavelength of the pulse spectrum sometimes deviates to the vicinity of the start wavelength λs and the end wavelength λe. As a result, the light intensity I near the start wavelength λs and the end wavelength λe in the cumulative spectrum waveform becomes higher, and sometimes the ideal flat-topped cumulative spectrum waveform is not obtained.

[0140] In the embodiments described below, the incident angles α1 and α2 are varied in such a way that the phase or variation range of the first incident angle α1 of the first portion 91 and the second incident angle α2 of the second portion 92 of the beam 90 incident on the grating 53 is different. This allows for the realization of a flat-topped cumulative spectrum waveform with a wide wavelength range Δλ.

[0141] 2. A laser device 100a with different phases at the first and second incident angles α1 and α2.

[0142] 2.1 Structure

[0143] Figure 12 The structure of the laser device 100a according to the first embodiment is shown in a schematic diagram. Figure 12 Equivalent to from the comparative example Figure 2 The image obtained by observing the laser device 100a from the same direction. Laser device 100a replaces... Figure 2 The mirror 63 shown has a first mirror 61 and a second mirror 62. Figure 13 These are stereoscopic images of mirrors 61 and 62, the first and second lenses.

[0144] The first and second mirrors 61 and 62 are arranged side by side in a direction parallel to the V-axis. The surfaces of the first and second mirrors 61 and 62 that reflect the beam 90 are parallel to the V-axis, and they are respectively rotatable about axes A11 and A12 parallel to the V-axis via rotary stages 161 and 162. Preferably, the first and second mirrors 61 and 62 are arranged close together, for example, with a spacing of less than 0.5 mm, to prevent collisions and suppress energy loss. The rotary stages 161 and 162 constituting the actuator system 160 correspond to the first and second actuators, respectively.

[0145] The first and second mirrors 61 and 62 are configured such that a beam 90, output from the laser cavity 10 and passing through prisms 41-43, is incident on the first and second mirrors 61 and 62 in a manner that spans across them. The portion of the beam 90 incident on the first mirror 61 is designated as portion 91, and the portion incident on the second mirror 62 is designated as portion 92. Figure 13 The central axis of the optical path of portions 91 and 92 is shown. Portions 91 and 92 are reflected by mirrors 61 and 62 and are incident on grating 53. Grating 53 is an example of a grating system in this disclosure.

[0146] Based on the driving voltages V1 and V2 applied to the rotary stages 161 and 162 respectively, the rotation angles θ1 and θ2 of the first and second mirrors 61 and 62 change, and the reflection directions of the first and second portions 91 and 92 of the first and second mirrors 61 and 62 change accordingly. As a result, the first incident angle α1 of the first portion 91 and the second incident angle α2 of the second portion 92 incident on the grating 53 are adjusted. In this disclosure, the driving voltages V1 and V2 are sometimes collectively referred to as driving voltage V, and the rotation angles θ1 and θ2 are collectively referred to as rotation angle θ.

[0147] 2.2 Actions

[0148] Figure 14 This is a graph illustrating an example of the drive voltages V1 and V2 applied to the rotary tables 161 and 162 in the first embodiment. Figure 14 In the diagram, the horizontal axis represents time t, and the vertical axis represents driving voltages V1 and V2. The driving voltages V1 and V2 in the first embodiment have the following characteristics.

[0149] (a) The driving voltages V1 and V2 vary periodically with opposite phases. That is, the phase difference is π radians.

[0150] (b) Both drive voltages V1 and V2 vary between the start voltage Vs and the end voltage Ve. That is, the range of variation of drive voltages V1 and V2 is equal.

[0151] (c) The driving voltages V1 and V2 are both varied using the time 2N / F, which is obtained by multiplying the repetition period of the pulsed laser 1 / F by twice the number of irradiation pulses N, as the variation period.

[0152] Figure 15 Showing will Figure 14 The diagram shows the cumulative spectrum waveforms of N / F over half a cycle when driving voltages V1 and V2 are applied to rotary stages 161 and 162, respectively. Figure 15 In the diagram, the horizontal axis represents wavelength λ, and the vertical axis represents light intensity I. According to the first embodiment, by applying driving voltages V1 and V2 with opposite phases to the rotating stages 161 and 162, the first and second incident angles α1 and α2 also vary with opposite phases between the starting incident angle αs and the ending incident angle αe. Thus, even the cumulative spectral waveform of half a period N / F becomes a flat-topped spectral waveform with a substantially uniform light intensity I between the starting wavelength λs and the ending wavelength λe.

[0153] Figure 16 This is a graph showing a variation of the driving voltages V1 and V2 applied to the rotary tables 161 and 162 in the first embodiment. Figure 16 In the diagram, the horizontal axis represents time t, and the vertical axis represents the driving voltages V1 and V2. Figure 16In this circuit, the phase difference between the driving voltages V1 and V2 is slightly offset relative to π radians. When the phases are not opposite, the cumulative spectrum waveform of half a cycle N / F may vary rather than remain constant. The magnitude of this variation depends on the phase difference. If the phase difference is greater than 7π / 8 radians but less than 9π / 8 radians, the variation in the cumulative spectrum waveform is small, thus achieving a certain level of exposure performance.

[0154] Figure 17 This is a flowchart illustrating the process of setting the start voltage Vs and end voltage Ve in the first embodiment. The laser control processor 130 calculates the start voltage Vs and end voltage Ve based on the cumulative spectrum center wavelength λ0 and wavelength range Δλ as follows.

[0155] In S1, the laser control processor 130 receives data on the cumulative spectrum center wavelength λ0 and wavelength range Δλ from the exposure control processor 210.

[0156] In S2, the laser control processor 130 calculates the start wavelength λs and the end wavelength λe using the following formula.

[0157] λs=λ0-Δλ / 2

[0158] λe=λ0+Δλ / 2

[0159] In S3, the laser control processor 130 reads the relationship between wavelength λ and rotation angles θ1 and θ2 from memory 132, λ = f(θ), and calculates the starting rotation angle θs and ending rotation angle θe corresponding to the starting wavelength λs and the ending wavelength λe. The starting rotation angle θs and the ending rotation angle θe are the same in rotation angles θ1 and θ2.

[0160] In step S4, the laser control processor 130 reads the relationship between rotation angles θ1 and θ2 and driving voltages V1 and V2 from the memory 132, θ = g(V), and calculates the starting voltage Vs and ending voltage Ve corresponding to the starting rotation angle θs and the ending rotation angle θe. The starting voltage Vs and ending voltage Ve are the same in driving voltages V1 and V2.

[0161] After calculating the start voltage Vs and end voltage Ve, drive voltages V1 and V2 with opposite phases are applied to the rotary stages 161 and 162 with a variation period of 2N / F, thereby obtaining a flat-topped cumulative spectrum waveform.

[0162] After S4, the laser control processor 130 ends the processing of this flowchart.

[0163] This description illustrates how the rotation angles θ1 and θ2 of the first and second mirrors 61 and 62 change according to the drive voltages V1 and V2 via rotary stages 161 and 162. However, this disclosure is not limited to this. Rotary stages 161 and 162 can also be constructed using stepper motors, allowing the rotation angles θ1 and θ2 of the first and second mirrors 61 and 62 to change according to the count value of control pulses.

[0164] 2.3 Function

[0165] (1) According to the first embodiment, the laser device 100a includes a grating 53, an actuator system 160, and a laser control processor 130. The actuator system 160 adjusts a first portion 91 of a beam 90 incident on the grating 53 at a first incident angle α1 relative to the grating 53 and a second portion 92 of the beam 90 at a second incident angle α2 relative to the grating 53. The laser control processor 130 controls the actuator system 160, thereby periodically varying the first and second incident angles α1 and α2 in a phase-different manner.

[0166] This allows for smoother changes in the first and second incident angles α1 and α2. Consequently, the actuator system 160's operation can follow the control signal, and the accumulated spectrum waveform can approach the ideal waveform.

[0167] (2) According to the first embodiment, the laser device 100a includes a first mirror 61 disposed in the optical path of the first part 91 and a second mirror 62 disposed in the optical path of the second part 92.

[0168] Therefore, the first and second incident angles α1 and α2 can be adjusted using the first and second mirrors 61 and 62.

[0169] (3) According to the first embodiment, the laser device 100a includes a laser cavity 10 that outputs a beam 90; and prisms 41 to 43 that widen the beam width of the beam 90 so that the beam 90 is incident on the first and second mirrors 61 and 62 in a manner that crosses the first and second mirrors 61 and 62.

[0170] Therefore, even without branching the beam at 90°, it is possible to adjust the first and second incident angles α1 and α2.

[0171] (4) According to the first embodiment, the actuator system 160 includes a rotary table 161 for changing the first incident angle α1 and a rotary table 162 for changing the second incident angle α2.

[0172] Therefore, the first and second incident angles α1 and α2 can be varied respectively.

[0173] (5) According to the first embodiment, the laser control processor 130 changes the first and second incident angles α1 and α2 in such a way that the phase difference is greater than or equal to 7π / 8 radians and less than or equal to 9π / 8 radians.

[0174] Therefore, by making the phases of the first and second incident angles α1 and α2 approximately opposite, even the cumulative spectrum waveform of half a period N / F can be set to a flat top. Furthermore, since the first and second mirrors 61 and 62 rotate in opposite directions, the sum of the angular motions of the first and second mirrors 61 and 62 is stabilized at a small value. Thus, the overall mechanical vibration of the device is small, enabling stable wavelength control.

[0175] (6) According to the first embodiment, the laser control processor 130 varies the first and second incident angles α1 and α2 in such a way that the variation ranges of the first and second incident angles α1 and α2 are equal to each other.

[0176] This allows for the suppression of load concentration on a single actuator.

[0177] (7) According to the first embodiment, the laser control processor 130 changes the first and second incident angles α1 and α2 by multiplying the pulse repetition period 1 / F of the pulsed laser output from the laser device 100a by twice the number of irradiation pulses N of the pulsed laser irradiating one part of the irradiated object by the variation period 2N / F.

[0178] Therefore, by varying the first and second incident angles α1 and α2 by a variation period 2N / F that is twice the time T required to move the scanning field SF by a distance equivalent to the width W of the beam cross section B of the pulsed laser, the variation of the first and second incident angles α1 and α2 can be made gradual.

[0179] In other respects, the first embodiment is the same as the comparative example.

[0180] 3. Laser device 100a with different ranges of variation for the first and second incident angles α1 and α2.

[0181] 3.1 Structure and Action

[0182] Figures 18-20 This is a graph showing several examples of the drive voltages V1 and V2 applied to the rotary tables 161 and 162 in the second embodiment. Figures 18-20 In the diagram, the horizontal axis represents time t, and the vertical axis represents the driving voltages V1 and V2. The structure and reference of the second embodiment are as follows. Figure 12 The structure is the same as that of the first embodiment described. The driving voltages V1 and V2 in the second embodiment have the following characteristics.

[0183] (a) The driving voltages V1 and V2 vary periodically within different ranges.

[0184] (b) The driving voltages V1 and V2 vary the time N / F obtained by multiplying the repetition period 1 / F of the pulsed laser by the number of irradiation pulses N.

[0185] (c) The phases of the driving voltages V1 and V2 can be the same, opposite, or have other phase differences.

[0186] Figure 18 This illustrates the case where the driving voltages V1 and V2 are out of phase. Figure 19 This illustrates the case where the driving voltages V1 and V2 are in phase. Figure 20 This illustrates a case where the driving voltages V1 and V2 have phases that are neither the same nor opposite, but rather have other phase differences. Figures 18-20 In either case, the cumulative spectral waveform of one period N / F becomes a flat-topped spectral waveform.

[0187] Figure 21 This is a graph showing an example of the first incident angle α1 of the first portion 91 and the second incident angle α2 of the second portion 92 incident on the grating 53 in the second embodiment. Figure 21 In the diagram, the horizontal axis represents time t, and the vertical axis represents the first and second incident angles α1 and α2. Figure 21 The small circles shown represent the timing of the pulsed laser output and the first and second incident angles α1 and α2 at that time.

[0188] like Figure 21 As shown, the range of variation of the first incident angle α1 in Part 1 91 is from the first starting incident angle αs1 to the first ending incident angle αe1, which is larger than the first starting incident angle αs1. The range of variation of the second incident angle α2 in Part 2 92 is from the second starting incident angle αs2, which is larger than the first starting incident angle αs1, to the second ending incident angle αe2, which is larger than the second starting incident angle αs2. The first starting incident angle αs1 corresponds to the first value in this disclosure, the first ending incident angle αe1 corresponds to the second value in this disclosure, the second starting incident angle αs2 corresponds to the third value in this disclosure, and the second ending incident angle αe2 corresponds to the fourth value in this disclosure.

[0189] Preferably, the second starting incident angle αs2 is greater than or equal to the first ending incident angle αe1.

[0190] exist Figure 21 The diagram illustrates the case where the first and second incident angles α1 and α2 are in phase; however, this disclosure is not limited thereto. (See reference...) Figures 18-20 As explained, the phases of the first and second incident angles α1 and α2 can be the same, opposite, or have other phase differences.

[0191] Figure 22 This is a flowchart illustrating the process of setting the first start voltage Vs1, the first end voltage Ve1, the second start voltage Vs2, and the second end voltage Ve2 in the second embodiment. The first start voltage Vs1, the first end voltage Ve1, the second start voltage Vs2, and the second end voltage Ve2 correspond to the first start incident angle αs1, the first end incident angle αe1, the second start incident angle αs2, and the second end incident angle αe2, respectively.

[0192] S1 processing and reference Figure 17 The processing described is the same.

[0193] In S2b, the laser control processor 130 calculates the first starting wavelength λs1, the first ending wavelength λe1, the second starting wavelength λs2, and the second ending wavelength λe2 corresponding to the first starting incident angle αs1, the first ending incident angle αe1, the second starting incident angle αs2, and the second ending incident angle αe2, respectively, using the following formulas.

[0194] λs1=λ0-Δλ / 2

[0195] λe1=λ0

[0196] λs2=λ0

[0197] λe2=λ0+Δλ / 2

[0198] In S3b, the laser control processor 130 calculates the first starting rotation angle θs1, the first ending rotation angle θe1, the second starting rotation angle θs2, and the second ending rotation angle θe2 corresponding to the first starting wavelength λs1, the first ending wavelength λe1, the second starting wavelength λs2, and the second ending wavelength λe2, respectively.

[0199] In S4b, the laser control processor 130 calculates the first start voltage Vs1, the first end voltage Ve1, the second start voltage Vs2, and the second end voltage Ve2 corresponding to the first start rotation angle θs1, the first end rotation angle θe1, the second start rotation angle θs2, and the second end rotation angle θe2, respectively.

[0200] Regarding other aspects, Figure 22 The processing shown is the same as Figure 17 The processing shown is the same.

[0201] Figure 23 This is a graph showing a modified example of the first and second incident angles α1 and α2 in the second embodiment. Figure 23 In the diagram, the horizontal axis represents time t, and the vertical axis represents the first and second incident angles α1 and α2. Figure 23The small circles shown represent the timing of the pulsed laser output and the first and second incident angles α1 and α2 at that time.

[0202] like Figure 23 As shown, the second starting incident angle αs2 can be larger than the first ending incident angle αe1. Preferably, the difference αs2-αe1 between the second starting incident angle αs2 and the first ending incident angle αe1 is less than or equal to the variation Δα of the first or second incident angle α1 or α2 for each pulse.

[0203] In addition, such as Figure 21 and Figure 23 As shown, preferably, the difference αe1-αs1 between the first starting incident angle αs1 and the first ending incident angle αe1 is equal to the difference αe2-αs2 between the second starting incident angle αs2 and the second ending incident angle αe2.

[0204] Figure 24 An example of the cumulative spectrum waveform of one period N / F in the second embodiment is shown. The horizontal axis represents the wavelength λ, and the vertical axis represents the light intensity I. Figure 24 The spectral waveforms of pulses P1 to P6 contained in one period N / F are shown together. Pulses P1 to P3 are included in Part 1, 91, and pulses P4 to P6 are included in Part 2, 92.

[0205] The first ending wavelength λe1 corresponds to the center wavelength of the first pulse spectrum when the first incident angle α1 is set to the first ending incident angle αe1. The second starting wavelength λs2 corresponds to the center wavelength of the second pulse spectrum when the second incident angle α2 is set to the second starting incident angle αs2. The second starting wavelength λs2 can be larger than the first ending wavelength λe1. That is, the second starting incident angle αs2 can be larger than the first ending incident angle αe1. Preferably, the difference between the first ending wavelength λe1 and the second starting wavelength λs2, λs2-λe1, is equal to the full width at half maximum (FWHM) of the pulse spectrum waveform of any one of pulses P1 to P6.

[0206] Figure 25 A variation of the cumulative spectrum waveform for one period N / F in the second embodiment is shown. The horizontal axis represents wavelength λ, and the vertical axis represents light intensity I. The first cumulative spectrum waveform WF1 is the cumulative spectrum waveform when the first incident angle α1 is periodically varied, and the second cumulative spectrum waveform WF2 is the cumulative spectrum waveform when the second incident angle α2 is periodically varied. The peak intensities of the first cumulative spectrum waveform WF1 and the second cumulative spectrum waveform WF2 are set to Imax.

[0207] The preferred cumulative spectrum waveforms WF1 and WF2 cross at their respective half-values ​​Imax / 2.

[0208] 3.2 Function

[0209] (8) According to the second embodiment, the range of variation of the first incident angle α1 is from the first starting incident angle αs1 to the first ending incident angle αe1 which is larger than the first starting incident angle αs1, and the range of variation of the second incident angle α2 is from the second starting incident angle αs2 which is larger than the first starting incident angle αs1 to the second ending incident angle αe2 which is larger than the second starting incident angle αs2.

[0210] Therefore, by setting the variation ranges of the first and second incident angles α1 and α2 to be different from each other, the variation of the first and second incident angles α1 and α2 can be made gradual. As a result, the operation of the actuator system 160 can follow the control signal, and the cumulative spectrum waveform can be made close to the ideal waveform.

[0211] (9) According to the second embodiment, the second starting incident angle αs2 is greater than or equal to the first ending incident angle αe1.

[0212] This reduces the overlap of the variation ranges of the first and second incident angles α1 and α2, making the variation of the first and second incident angles α1 and α2 more gradual.

[0213] (10) According to the second embodiment, the difference αs2-αe1 between the first ending incident angle αe1 and the second starting incident angle αs2 is less than or equal to the variation Δα of either the first or second incident angle α1 or α2 of each pulse of the pulsed laser output from the laser device 100a.

[0214] This allows us to obtain a flat-topped cumulative spectrum waveform.

[0215] (11) According to the second embodiment, the difference αe1-αs1 between the first starting incident angle αs1 and the first ending incident angle αe1 is equal to the difference αe2-αs2 between the second starting incident angle αs2 and the second ending incident angle αe2.

[0216] Therefore, by making the variation amplitudes of the first and second incident angles α1 and α2 equal, it is possible to suppress the concentration of load on a single actuator.

[0217] (12) According to the second embodiment, the difference λs2-λe1 between the first ending wavelength λe1 when the first incident angle α1 is set as the first ending incident angle αe1 and the second starting wavelength λs2 when the second incident angle α2 is set as the second starting incident angle αs2 is equal to the full width at half maximum (FWHM) of the pulse spectrum waveform of either the first or the second part 91 and 92.

[0218] This allows the cumulative spectrum waveform to approach a flat-top shape.

[0219] (13) According to the second embodiment, the first cumulative spectrum waveform WF1 when the first incident angle α1 is periodically varied and the second cumulative spectrum waveform WF2 when the second incident angle α2 is periodically varied cross at their respective half-values ​​Imax / 2.

[0220] Therefore, the overall cumulative spectrum waveform, which combines the first and second cumulative spectrum waveforms WF1 and WF2, is made to be nearly flat-topped.

[0221] In other respects, the second embodiment is the same as the first embodiment.

[0222] 4. A laser device 100c that adjusts the first and second incident angles α1 and α2 according to the rotation angles θ1 and θ2 of prisms 44 and 45.

[0223] 4.1 Structure and Action

[0224] Figure 26 The structure of the laser device 100c according to the third embodiment is shown in a schematic diagram. Figure 26 Equivalent to from the comparative example Figure 2 The image obtained by observing the laser device 100c from the same direction. Laser device 100c replaces... Figure 2 The prism 43 shown has prisms 44 and 45. Figure 27 These are stereoscopic images of prisms 44 and 45. Figure 28 These are side views of prisms 44 and 45. Figure 27 This is equivalent to the image obtained by observing prisms 44 and 45 in a direction parallel to the VH plane. Figure 28 This is equivalent to the image obtained by observing prisms 44 and 45 in the -H direction. Prisms 44 and 45 correspond to the first and second prisms in this disclosure.

[0225] Prisms 44 and 45 are arranged side-by-side in a direction parallel to the V-axis. Prisms 44 and 45 are configured such that the surfaces of both prisms 44 and 45, which are used for incident and exit of the beam 90, are parallel to the V-axis, and can be rotated about axes A21 and A22 parallel to the V-axis via rotary stages 144 and 145, respectively. Rotary stages 144 and 145 constituting the actuator system 140 correspond to the first and second actuators, respectively.

[0226] Prisms 44 and 45 are configured such that a beam 90, output from the laser cavity 10 and passing through prisms 41 and 42, is incident on prisms 44 and 45 in a manner that crosses prisms 44 and 45. One of prisms 41 and 42 corresponds to the third prism in this disclosure. The portion of the beam 90 incident on prism 44 is designated as the first portion 91, and the portion incident on prism 45 is designated as the second portion 92. The first and second portions 91 and 92, respectively, pass through prisms 44 and 45, are reflected by mirror 63, and are incident on grating 53.

[0227] Based on the driving voltages V1 and V2 applied to the rotary stages 144 and 145 respectively, the rotation angles θ1 and θ2 of prisms 44 and 45 change, and the refraction directions of the first and second portions 91 and 92 of prisms 44 and 45 change accordingly. As a result, the first incident angle α1 of the first portion 91 and the second incident angle α2 of the second portion 92 incident on the grating 53 change.

[0228] 4.2 Function

[0229] (14) According to the third embodiment, the laser device 100c includes a prism 44 disposed in the optical path of the first part 91 and a prism 45 disposed in the optical path of the second part 92.

[0230] Therefore, prisms 44 and 45 can be used to adjust the first and second incident angles α1 and α2.

[0231] (15) According to the third embodiment, the laser device 100c includes a laser cavity 10 that outputs a beam 90; and prisms 41 and 42 that widen the beam width of the beam 90 so that the beam 90 is incident on prisms 44 and 45 in a manner that crosses prisms 44 and 45.

[0232] Therefore, even without branching the beam at 90°, it is possible to adjust the first and second incident angles α1 and α2.

[0233] In other respects, the third embodiment is the same as the first or second embodiment.

[0234] 5. A laser device 100d that adjusts the first and second incident angles α1 and α2 according to the rotation angles θ1 and θ2 of the first and second gratings 51 and 52.

[0235] 5.1 Structure and Action

[0236] Figure 29 The structure of the laser device 100d according to the fourth embodiment is shown in a schematic diagram. Figure 29 Equivalent to from the comparative example Figure 2 The image obtained by observing the laser device 100d from the same direction. Laser device 100d replaces... Figure 2 The grating 53 shown has first and second gratings 51 and 52. Figure 30 This is a perspective view of the first and second gratings 51 and 52. The first and second gratings 51 and 52 are an example of the grating system in this disclosure.

[0237] The first and second gratings 51 and 52 are arranged side by side in a direction parallel to the V-axis. The first and second gratings 51 and 52 are configured such that the direction of their respective slots is parallel to the V-axis, and they are respectively rotatable by rotary stages 151 and 152 about axes A31 and A32 parallel to the V-axis. The rotary stages 151 and 152 constituting the actuator system 150 correspond to the first and second actuators, respectively.

[0238] The beam 90 output from the laser cavity 10 passes through prisms 41-43, is reflected by mirror 63, and is incident on the first and second gratings 51 and 52 in a manner that crosses the first and second gratings 51 and 52. The portion of the beam 90 that is incident on the first grating 51 is designated as the first portion 91, and the portion that is incident on the second grating 52 is designated as the second portion 92.

[0239] According to the driving voltages V1 and V2 applied to the rotary tables 151 and 152 respectively, the rotation angles θ1 and θ2 of the first and second gratings 51 and 52 change respectively. As a result, the first incident angle α1 incident on the first part 91 of the first grating 51 and the second incident angle α2 incident on the second part 92 of the second grating 52 change.

[0240] 5.2 Function

[0241] (16) According to the fourth embodiment, the laser device 100d includes a first grating 51 disposed on the optical path of the first part 91 and a second grating 52 disposed on the optical path of the second part 92 as a grating system.

[0242] Therefore, the first and second incident angles α1 and α2 can be adjusted using the first and second gratings 51 and 52.

[0243] (17) According to the fourth embodiment, the laser device 100d includes a laser cavity 10 that outputs a beam 90; and prisms 41 to 43 that widen the beam width of the beam 90 so that the beam 90 is incident on the first and second gratings 51 and 52 in a manner that spans the first and second gratings 51 and 52.

[0244] Therefore, even without branching the beam at 90°, it is possible to adjust the first and second incident angles α1 and α2.

[0245] (18) According to the first to fourth embodiments, the laser control processor 130 causes the first and second incident angles α1 and α2 to vary in a triangular wave shape.

[0246] Therefore, the variation amplitude Δα of the first and second incident angles α1 and α2 can be kept approximately constant, resulting in a flat-topped cumulative spectrum waveform.

[0247] In other respects, the fourth embodiment is the same as the first or second embodiment.

[0248] 6. A laser device 100a that causes the first and second incident angles α1 and α2 to vary in a sinusoidal pattern.

[0249] 6.1 Structure and Action

[0250] In the above embodiments, the first and second incident angles α1 and α2 are made to vary in a triangular wave shape, but this disclosure is not limited thereto. The first and second incident angles α1 and α2 can also vary in a sinusoidal wave shape.

[0251] Figure 31 This illustrates the application of the fifth embodiment to the rotary tables 161 and 162 (see Figure 5). Figure 12 The graph shows an example of the driving voltages V1 and V2. Figure 31 In the diagram, the horizontal axis represents time t, and the vertical axis represents the driving voltages V1 and V2.

[0252] Figure 32 Showing will Figure 31 The cumulative spectrum waveform of N / F for half a cycle is shown when driving voltages V1 and V2 are applied to rotary stages 161 and 162. Figure 32 In the diagram, the horizontal axis represents wavelength λ, and the vertical axis represents light intensity I. In the fifth embodiment, by varying the driving voltages V1 and V2 in a sinusoidal pattern, the first and second incident angles α1 and α2 vary in a sinusoidal pattern. Therefore, in the cumulative spectrum waveform, the light intensity I near the start wavelength λs and the end wavelength λe increases.

[0253] 6.2 Function

[0254] (19) According to the fifth embodiment, the laser control processor 130 causes the first and second incident angles α1 and α2 to vary in a sinusoidal shape.

[0255] Therefore, by suppressing the abrupt changes in the angular velocities of the first and second mirrors 61 and 62, the actuator system 160 can be made to follow the control signal.

[0256] In other respects, the fifth embodiment is the same as the first embodiment.

[0257] Alternatively, in embodiments 2 to 4, the driving voltages V1 and V2 may vary in a sinusoidal pattern, thereby causing the first and second incident angles α1 and α2 to vary in a sinusoidal pattern.

[0258] 7. Other

[0259] The foregoing description is not a limitation but a simple illustration. Therefore, those skilled in the art will understand that modifications can be made to embodiments of this disclosure without departing from the claims. Furthermore, those skilled in the art will understand the use of embodiments of this disclosure in combination.

[0260] Unless explicitly stated otherwise, all terms used in this specification and claims should be interpreted as "non-limiting." For example, terms such as "comprising," "having," "possessing," and "comprise" should be interpreted as "excluding the presence of structural elements other than the described structural elements." Furthermore, the modifier "a" should be interpreted as meaning "at least one" or "one or more." Additionally, terms such as "at least one of A, B, and C" should be interpreted as "A," "B," "C," "A+B," "A+C," "B+C," or "A+B+C." Moreover, it should be interpreted as also including combinations of these elements with portions other than "A," "B," and "C."

Claims

1. A laser device comprising: grating system; An actuator system that adjusts a first portion of a light beam incident on the grating system at a first incident angle relative to the grating system and a second portion of the light beam at a second incident angle relative to the grating system, the actuator system comprising: a first actuator that causes the first incident angle to vary; And a second actuator, which causes the second incident angle to change; as well as A processor controls the actuator system such that the first and second incident angles vary periodically on the time axis of a waveform representing the periodic variation of the first and second incident angles, such that the phase difference is greater than 7π / 8 radians and less than 9π / 8 radians.

2. The laser device according to claim 1, wherein, The laser device also has: A first mirror, which is positioned in the optical path of the first part; and The second mirror is positioned in the optical path of the second part.

3. The laser device according to claim 2, wherein, The laser device also has: A laser cavity that outputs the laser beam; and At least one prism that widens the beam width so that the beam is incident on the first and second mirrors in a manner that spans the first and second mirrors.

4. The laser device according to claim 1, wherein, The processor varies the first and second incident angles in such a way that the ranges of variation of the first and second incident angles are equal to each other.

5. The laser device according to claim 1, wherein, The processor causes the first incident angle and the second incident angle to vary by a variation period obtained by multiplying the pulse repetition period of the pulsed laser output from the laser device by twice the number of pulsed laser pulses irradiating one part of the irradiated object.

6. The laser device according to claim 1, wherein, The laser device also has: A first prism, which is disposed in the optical path of the first part; and The second prism is positioned in the optical path of the second part.

7. The laser device according to claim 6, wherein, The laser device also has: A laser cavity that outputs the laser beam; and A third prism widens the beam width, causing the beam to be incident on the first and second prisms in a manner that spans across them.

8. The laser device according to claim 1, wherein, The grating system includes: A first grating, which is disposed in the optical path of the first portion; and The second grating is arranged in the optical path of the second part.

9. The laser device according to claim 8, wherein, The laser device also has: A laser cavity that outputs the laser beam; and At least one prism that widens the beam width so that the beam is incident on the first and second gratings in a manner that spans the first and second gratings.

10. The laser device according to claim 1, wherein, The processor causes the first incident angle and the second incident angle to vary in a triangular wave shape.

11. The laser device according to claim 1, wherein, The processor causes the first incident angle and the second incident angle to vary in a sinusoidal pattern.

12. A method for manufacturing an electronic device, comprising the following steps: Laser is generated by a laser device. The laser is output to the exposure device. The laser is exposed on a photosensitive substrate within the exposure apparatus to manufacture the electronic device. The laser device has: grating system; An actuator system that adjusts a first portion of a light beam incident on the grating system at a first incident angle relative to the grating system and a second portion of the light beam at a second incident angle relative to the grating system, the actuator system comprising: a first actuator that causes the first incident angle to vary; And a second actuator, which causes the second incident angle to change; as well as A processor controls the actuator system such that the first and second incident angles vary periodically on the time axis of a waveform representing the periodic variation of the first and second incident angles, such that the phase difference is greater than 7π / 8 radians and less than 9π / 8 radians.

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