Accelerator coherent light source device, control method thereof, and photolithography system

Abstract

The present disclosure provides an accelerator coherent light source device with adjustable width of output pulse, a control method thereof, and a photolithography system. A wavefront rotating laser is provided by a modulation laser optical platform (100), and an electron beam is modulated in a modulation device (200) to form a micro-bunch structure, so that the width of coherent radiation pulses output by a radiation undulator (300) is adjustable. By adjusting the distance between a grating pair (110, 120) in the modulation laser optical platform (100), the degree of wavefront rotation of the modulation laser can be controlled, so that the degree of wavefront rotation increases with the increase of the grating pair spacing, the width of the micro-bunch in the electron beam modulated by the wavefront rotating laser decreases accordingly, and further the pulse width output by the radiation undulator (300) is gradually shortened.

Description

Technical Field

[0001] This invention relates to the field of accelerator coherent light sources, and more specifically to an accelerator coherent light source device with continuously adjustable output pulse width and its control method, as well as a photolithography system equipped with the accelerator coherent light source device. Background Technology

[0002] Accelerator coherent light sources, due to their superior characteristics in brightness, power, and coherence, have gradually become major scientific platforms supporting basic research and high-tech development in fields such as physics, chemistry, biology, medicine, and materials science. Currently, accelerator coherent light source devices mainly include free-electron lasers based on electron linear accelerators and fully coherent light sources based on electron storage rings.

[0003] As the latest generation of photonic large-scale scientific devices, free-electron lasers can generate ultrashort, ultra-intense, fully coherent X-ray pulses. This provides a revolutionary tool for studying ultrafast dynamic processes at the atomic and molecular scale, and can be used to probe the structure of extremely microscopic matter and study the dynamic processes of matter transformation.

[0004] Storage ring light sources are characterized by high stability and high repetition rate. Diffraction-limited storage ring technology enhances the transverse coherence of the light source. Combined with free-electron laser technology, such as coherent harmonic generation (CHG), the longitudinal coherence of the storage ring light source can also be greatly improved. Therefore, a fully coherent storage ring light source combining these technologies possesses characteristics such as high stability, high repetition rate, high average power, and high coherence, offering unique advantages in scientific research and industrial applications.

[0005] On the other hand, with the development of technology, scientific research has also put forward new requirements for the pulse width of light sources. However, at present, accelerator coherent light source devices cannot achieve flexible control of the output pulse width. For example, in free-electron laser devices, adjusting the width of the output pulse is very difficult. Self-amplified spontaneous emission free-electron lasers require compressing or stretching the length of the electron beam in a linear accelerator. This process will change the operating state of the entire free-electron laser device and affect the normal operation of other beamlines. Seed-type free-electron lasers require compressing or stretching the length of the modulated laser. All of the above operations are quite difficult, especially the compression process, whether it is the electron beam or the modulated laser, to achieve several femtoseconds (1fs = 10^62 m / s). -15 s) and even attoseconds (1as = 10 -18 Compression of s) is extremely difficult. In addition, similar to seed-type free-electron lasers, storage ring coherent light sources also require compression or stretching of the modulated laser length to achieve adjustment of the output pulse width.

[0006] Therefore, accelerator coherent light source devices urgently need a simple control method that can continuously adjust the output radiation pulse width without changing the overall operating state of the device, and even achieve ultra-short pulse output of a few femtoseconds. Summary of the Invention

[0007] The technical problem to be solved by the present invention

[0008] In view of the above, the purpose of this invention is to provide an accelerator coherent light source device and its control method that can continuously adjust the pulse width.

[0009] Technical means for solving technical problems

[0010] To address the aforementioned technical problems, according to some exemplary embodiments of this disclosure, an accelerator coherent light source device is provided, comprising: a modulated laser optical platform that applies transverse dispersion to an incident laser beam and outputs a wavefront-rotating laser as a modulated laser; a modulation device that uses the modulated laser to modulate an electron beam generated by an accelerator and outputs a clustered electron beam; and a radiation undulator that provides a gain medium for the clustered electron beam and outputs a coherent radiation pulse.

[0011] In some embodiments, the width of the coherent radiation pulse varies according to the degree of wavefront rotation of the modulated laser output by the modulated laser optical platform.

[0012] In some embodiments, the modulated laser optical platform includes a grating pair consisting of a first grating and a second grating arranged in parallel, and the degree of wavefront rotation applied by the modulated laser optical platform varies according to the distance between the first grating and the second grating.

[0013] In some embodiments, the modulated laser optical platform further includes a displacement stage capable of changing the distance between the first grating and the second grating, wherein the first grating is fixedly disposed and the second grating is disposed on the displacement stage.

[0014] In some embodiments, the modulated laser optical platform further includes a first reflector, and the incident laser beam is reflected to the modulation device via the first reflector after being diffracted by the first grating and the second grating.

[0015] In some embodiments, the modulation device includes a second mirror, a modulation undulator, a magnetic compressor, and a third mirror arranged sequentially along the transmission direction of the electron beam. The modulated laser is incident on the undulator via the second mirror, where it exchanges energy with the electron beam to modulate the energy of the electron beam. The modulated laser then exits the modulation device via the third mirror. The magnetic compressor performs density modulation on the energy-modulated electron beam to output the clustered electron beam.

[0016] In some embodiments, the magnetic compressor includes four dipolar magnets.

[0017] In some embodiments, a bending magnet is provided downstream of the radiation undulator, causing the output coherent radiation pulse to separate from the electron beam.

[0018] In some embodiments, the modulated laser optical platform includes a prism pair consisting of a first prism and a second prism arranged symmetrically, and the degree of wavefront rotation applied by the modulated laser optical platform varies according to the distance between the first prism and the second prism.

[0019] According to some exemplary embodiments of this disclosure, a lithography system is also provided, including the above-described accelerator coherent light source device.

[0020] According to some exemplary embodiments of this disclosure, a control method for an accelerator coherent light source device is also provided. The accelerator coherent light source device includes a modulated laser optical platform, a modulation device, and a radiation undulator. The control method includes the following steps: injecting an electron beam generated by an accelerator into the modulation device; introducing a laser beam into the modulated laser optical platform, wherein the modulated laser optical platform applies transverse dispersion to the laser beam and outputs a wavefront-rotating laser as a modulated laser; the modulation device modulates the electron beam using the modulated laser, causing the electron beam to cluster and output; and the radiation undulator provides a gain medium for the electron beam output from the modulation device, thereby outputting a coherent radiation pulse.

[0021] Invention Effects

[0022] The accelerator coherent light source device of this invention utilizes a modulated laser optical platform to provide a wavefront-rotating laser as the modulated laser. In the modulation device, the electron beam is modulated to form a micro-focused structure, making the width of the coherent radiation pulse output by the radiation undulator adjustable. Adjusting the distance between the grating pairs in the modulated laser optical platform controls the degree of wavefront rotation of the modulated laser. The wavefront rotation increases with increasing grating pair spacing, and the width of the micro-focused beam in the electron beam modulated by the wavefront-rotating laser decreases accordingly, thereby gradually shortening the pulse width output by the radiation undulator. Therefore, the width of the coherent radiation pulse can be easily adjusted. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the embodiments of the present disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings:

[0024] Figure 1 This is a structural block diagram of an accelerator coherent light source device according to an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the modulated laser optical platform in the coherent light source device of the accelerator according to an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the wavefront rotating laser in the accelerator coherent light source device according to an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the modulation device and radiation undulator in the coherent light source device of the accelerator according to an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the electron beam in the coherent light source device of the accelerator according to an embodiment of the present invention after being modulated by a wavefront rotating laser.

[0029] Figure 6 This is a schematic diagram showing the distribution of electron beam clusters after wavefront rotation laser modulation at different degrees of rotation;

[0030] Figure 7 This is a schematic diagram of the power distribution of the output pulses after wavefront rotation laser modulation at different degrees of rotation;

[0031] Figure 8 These are the spectra of the output pulses after wavefront rotation laser modulation at different degrees of rotation;

[0032] Figure 9 This is a flowchart of the control method of the accelerator coherent light source device according to an embodiment of the present invention;

[0033] Figure 10This is another schematic diagram of the modulated laser optical platform in the coherent light source device of the accelerator according to an embodiment of the present invention. Detailed Implementation

[0034] The following describes specific embodiments of this disclosure. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. It should be understood that, in the actual implementation of any embodiment, just as in any engineering or design project, various specific decisions are often made to achieve the developer's specific goals and to meet system-related or business-related constraints, and this can change from one embodiment to another. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this disclosure, changes in design, manufacturing, or production based on the technical content disclosed in this disclosure are merely conventional technical means and should not be construed as insufficient content of this disclosure.

[0035] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar words used in this patent application description and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms “an” or “a” and similar words do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar words mean that the element or object preceding “comprising” or “including” encompasses the element or object listed following “comprising” or “including” and its equivalents, and do not exclude other elements or objects. The terms “connected,” “coupled,” or “linked” and similar words are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0036] Unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions. Similarly, unless otherwise specified, all technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0037] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0038] The following describes in detail, with reference to the accompanying drawings, an accelerator coherent light source apparatus and its control method according to embodiments of the present disclosure.

[0039] Figure 1 This illustrates the basic structure of the accelerator coherent light source device 10 provided in an embodiment of the present invention. The accelerator coherent light source device 10 includes a modulated laser optical platform 100, a modulation device 200, and a radiation undulator 300.

[0040] The modulated laser optical platform 100 causes the input laser beam (e.g., a Gaussian laser pulse) to rotate its wavefront, and the resulting wavefront-rotated laser is input to the modulation device 200 as the modulated laser.

[0041] In the modulation device 200, the electron beam is modulated (including energy modulation and density modulation) using a wavefront rotating laser from the modulation laser optical platform 100, thereby forming a clustered electron beam.

[0042] The clustered electron beam generates optical gain in the radiation undulator 300, thereby outputting a fully coherent radiation pulse as the output pulse.

[0043] like Figure 1 As shown, the modulation device 200 and the radiation undulator 300 are arranged sequentially along the transmission direction of the electron beam. The direction of the laser beam incident on the modulation laser optical platform 100 is parallel to the transmission direction of the electron beam, and the modulation laser output from the modulation laser optical platform 100 enters the modulation device 200 perpendicular to the direction of the incident laser beam and the electron beam. However, the optical path design inside the accelerator coherent light source device of the present invention is not limited to this, and the direction of the beam and the electron beam can be designed according to actual needs.

[0044] Additionally, the electron beam and laser beam shown in the figure are respectively an electron beam generated by a linear accelerator (not shown) and a Gaussian laser beam emitted from a laser (not shown).

[0045] In the accelerator coherent light source device 10 of this embodiment, the electron beam is modulated by the wavefront rotating laser output from the modulated laser optical platform 100, and the width of the radiation pulse output by the accelerator coherent light source device 10 is controlled by adjusting the degree of wavefront rotation in the modulated laser optical platform 100.

[0046] Figure 2This is a schematic diagram showing the structure of the modulated laser optical platform 100. The modulated laser optical platform 100 includes a first grating 110, a second grating 120, a mirror 130, and displacement stages 140 and 150.

[0047] The first grating 110 and the second grating 120 are arranged parallel to each other to form a grating pair, with a distance g between them, as shown in the figure. A Gaussian laser incident on the modulation laser optical platform 100 first enters the first grating 110 at an incident angle γ. The incident Gaussian laser undergoes diffraction at the first grating 110 at a diffraction angle θ. The diffracted light exiting the first grating 110 propagates a distance (related to the distance g between the grating pairs) before entering the second grating 120. The second grating 120 diffracts the beam again, ultimately forming the output wavefront.

[0048] Since the diffraction angles θ of different wavelength components are different, the laser emitted from the second grating 120 will produce obvious transverse dispersion, that is, different wavelength components are distributed at different transverse positions.

[0049] Figure 3 This is a schematic diagram of the laser output after diffraction by the first grating 110 and the second grating 120. (See diagram below.) Figure 3 As shown, only the wavefront located in the center of the image (the surface formed by equiphase points, as shown by the dashed line) is perpendicular to the direction of laser propagation, while the wavefronts at other positions are at a certain angle Δβ relative to that position, meaning the wavefronts are tilted. Such a laser is called a wavefront rotation (WFR) laser, and the angle Δβ corresponds to the degree of wavefront rotation.

[0050] Unlike conventional lasers, which typically have a flat wavefront, wavefront-rotating lasers possess a unique wavefront shape; their wavefront is rotating. For example... Figure 3 As shown, from the frequency distribution, the wavefront-rotating laser exhibits significant transverse dispersion along the y-direction, which causes the laser wavefront to rotate. At any position of the wavefront-rotating laser, the variable β is defined to satisfy the following equation:

[0051] β=ω(y) / ω0 (1) where, ω(y): the angular frequency of the laser at position y;

[0052] ω0: The center angular frequency of the laser.

[0053] The speed of wavefront rotation v rot It can be defined as:

[0054]

[0055] Therefore, the angle between two adjacent wavefronts is:

[0056] Δβ=vrot T (3)

[0057] Where T represents the longitudinal interval between adjacent wavefronts.

[0058] For a plane wave, the velocity v of the wavefront rotation rot It is zero, but after Figure 2 The grating pair formed by the first grating 110 and the second grating 120 shown has a wavefront rotation speed v. rot The angle g will become a non-zero value due to the geometric configuration of the grating pair, causing the laser wavefront to rotate. That is, the spacing g of the grating pair will affect the tilt of the (amplified) wavefront, which is manifested as a change in the included angle Δβ.

[0059] Therefore, by adjusting the spacing g of the grating pair formed by the first grating 110 and the second grating 120, the rotation degree of the wavefront rotating laser can be adjusted.

[0060] The modulated laser optical platform 100 also includes displacement stages 140 and 150. The second grating 120 is mounted on the displacement stage 140, and the first grating 110 is fixedly set. Therefore, by controlling the displacement stage 140 to move, the distance g between the first grating 110 and the second grating 120 can be adjusted. Thus, as described above, the degree of wavefront rotation of the wavefront-rotating laser, i.e., the size of the angle Δβ between adjacent wavefronts, can be controlled.

[0061] Figure 2 In this process, the movement direction of the displacement stage 140 is perpendicular to the grating 120, but it is not limited to this. As long as the distance g between the grating pairs 110 and 120 can be adjusted, the movement direction of the displacement stage 140 can be set arbitrarily.

[0062] When the distance g between the first grating 110 and the second grating 120 is adjusted by the displacement stage 140, the position of the output wavefront rotating laser spot will also change accordingly. Therefore, in order to ensure the stable transmission of the wavefront rotating laser in the subsequent optical path, the reflector 130 is mounted on the displacement stage 150. The displacement stage 150 will move accordingly as the displacement stage 140 moves, thereby ensuring that the wavefront rotating laser is always incident on the reflector 130 at a fixed angle and reflected into the subsequent optical path at a fixed angle. In this embodiment, as... Figure 2 As shown, the propagation direction of the wavefront rotating laser output from the second grating 120 is parallel to the incident direction of the Gaussian laser, and the motion direction of the displacement stage 150 is parallel to the propagation direction of the wavefront rotating laser after being reflected by the reflector 130 (its subsequent optical path is omitted in the figure).

[0063] Thus, the wavefront rotating laser output from the modulated laser optical platform 100 is output to the modulation device 200 in a direction perpendicular to the incident direction of the Gaussian laser.

[0064] Figure 4 This is a schematic diagram of the modulation device 200 and the radiation undulator 300 in the coherent light source device 10 of the accelerator.

[0065] The modulation device 200 uses a wavefront-rotating laser from the modulation laser optical platform 100 to modulate the energy and density of the electron beam. For example... Figure 4 As shown, the modulation device 200 mainly includes a reflector 210, an undulator 220, a magnetic compressor 230, and a reflector 240.

[0066] The wavefront rotating laser, which is used as a modulated laser, is injected into the undulator 220 via the reflector 210, and interacts with the electron beam generated from the accelerator (not shown) in the undulator 220 to generate energy exchange and modulate the energy of the electron beam.

[0067] The magnetic compressor 230 consists of multiple diode magnets. Figure 4 As shown in four sections, the electron beam, after being modulated by the undulator 220, is magnetically compressed. The electron beam is deflected at the first diode magnet of the magnetic compressor 230 (i.e., the first diode magnet from the left in the figure), while the modulated laser is unaffected at this position and continues to propagate in its original direction. That is, the electron beam and the modulated laser are spatially separated at the first diode magnet.

[0068] Subsequently, the modulated laser is extracted from the modulation device 200 via mirror 240 to prevent interference with subsequent parts of the device. The electron beam then passes sequentially through the remaining diode magnets in the magnetic compressor 230. During this process, the electron beam is magnetically compressed, and the energy modulation it receives in the undulator 220 is converted into density modulation, resulting in micro-beaming of the electron beam.

[0069] Figure 5 This is a schematic diagram of the electron beam in the coherent light source device of the accelerator according to an embodiment of the present invention after being modulated by a wavefront rotating laser. Figure 5 The diagram shows the electron beam output from the modulation device 200, i.e., the electron beam distribution after wavefront-rotating laser modulation.

[0070] Therefore, we can understand the wavefront characteristics of wavefront-rotating lasers (such as...). Figure 3 As shown, the electron beam was shifted, meaning that relative to the electron beam distribution located in the center, the distribution on both sides was tilted (corresponding to...). Figure 3 The angle Δβ between adjacent wavefronts in the wavefront. Figure 5 In the process, the tilted structure on both sides of the electron beam will disrupt the clustering of the electron beam at that location, making the clustering on both sides of the electron beam smaller, which in turn weakens the radiation on both sides of the electron beam and narrows the width of the output radiation pulse.

[0071] Figure 6This is a schematic diagram showing the distribution of electron beam clusters modulated by wavefront-rotating lasers with different degrees of rotation. Here, we will use a modulated laser with a wavelength of 266nm as an example for illustration. Figure 6 In the diagram, curves a, b, c, and d represent the longitudinal distribution of the electron beam clustered at the entrance of the radiating undulator 300 after modulation by wavefront-rotated lasers with different degrees of wavefront rotation. The wavefront rotation degree of the modulated lasers corresponding to curves a, b, c, and d gradually decreases; that is, the wavefront rotation degree is greatest for curve a and smallest for curve d, for example, 0. In this case, the modulated laser corresponding to curve d is a normal Gaussian laser. Figure 6 It can be seen that as the degree of wavefront rotation increases, the width of the cluster becomes narrower and narrower.

[0072] Back Figure 4 ,have Figure 5 The electron beam of the micro-focused structure shown is transmitted to the radiation undulator 300 for radiation amplification, generating a fully coherent radiation pulse with adjustable pulse width. The radiation undulator 300 mainly includes an undulator 310 and a bending magnet 320. The undulator 310 generates a periodic magnetic field to amplify the electron beam, causing the electron beam to oscillate within the undulator 310. The bending magnet 320 is used to extract the electron beam from the radiation undulator 300, separating the output pulse from the electron beam.

[0073] Figure 7 It has Figure 6 The diagram shows the distribution of the radiation pulses output after the clustered electron beam passes through the undulator 310. For a modulated laser wavelength of 266nm, the output radiation pulse wavelength is selected in the simulation as the 10th harmonic of 266nm, i.e., 26.6nm. Figure 7 Curves a, b, c, and d in the diagram correspond to... Figure 6 Curves a, b, c, and d in the diagram. (The remaining text appears to be incomplete and requires further context. Figure 7 It can be seen that the width of the output pulse is highly consistent with the width of the cluster in the electron beam. That is, by controlling the degree of wavefront rotation of the wavefront-rotating laser, the distribution of the cluster in the electron beam can be controlled, and thus the pulse width of the output pulse can be controlled.

[0074] Figure 7 In the diagram, curve a corresponds to a pulse width of approximately 6 fs, thus enabling the generation of ultrashort pulses of a few femtoseconds. However, curve a does not represent the limit of this method. If the degree of modulation of the laser wavefront rotation is further enhanced, although the corresponding peak power will decrease, the width of the output pulse can be further shortened.

[0075] Figure 8 This is the spectrum of the pulse output from undulator 300. Similarly, curves a, b, c, and d correspond to... Figure 6 , Figure 7Curves a, b, c, and d in the diagram. (The remaining text appears to be incomplete and requires further context. Figure 8 It is known that as the output pulse width shortens, the output spectrum broadens accordingly, which is of great significance for scientific research on some ultrafast processes (such as molecular vibrations) or those requiring wide-bandwidth spectra (such as absorption spectroscopy).

[0076] According to the accelerator coherent light source apparatus 10 of this embodiment, a wavefront-rotating laser is provided by a modulated laser optical platform 100. This causes the micro-beam clustering structure formed by the electron beam after passing through the modulation device 200 to be additionally modulated by the wavefront structure of the modulated laser, thereby affecting the longitudinal distribution of the electron beam clustering and making the width of the output pulse of the radiation undulator 300 adjustable. Specifically, by adjusting the distance between the grating pairs 110 and 120 in the modulated laser optical platform 100, the degree of wavefront rotation of the modulated laser can be controlled, so that the degree of wavefront rotation increases with the increase of the grating pair spacing. The width of the micro-beam clustering in the electron beam modulated by the wavefront-rotating laser decreases accordingly, thereby gradually shortening the width of the output pulse of the radiation undulator 300. Thus, continuous adjustment of the radiation pulse width from a few femtoseconds to several hundred femtoseconds can be achieved, which can enhance the flexibility and applicability of the accelerator coherent light source apparatus.

[0077] Figure 9 This is a flowchart of a control method for an accelerator coherent light source device according to an embodiment of the present invention. The accelerator coherent light source device includes... Figure 2 The modulated laser optical platform 100, modulation device 200, and radiation undulator 300 shown are arranged along the transmission direction of the electron beam. The modulated laser optical platform 100 provides modulated laser to the modulation device 200 to modulate the electron beam. The control method includes the following steps.

[0078] S910: Continuously inject an electron beam generated by the accelerator into the modulation device 200.

[0079] S920: Gaussian laser is introduced into the modulation laser optical platform 100, and wavefront rotating laser is provided to the modulation device 200 as modulation laser by the diffraction of the Gaussian laser by the first grating 110 and the second grating 120.

[0080] S930: In the modulation device 200, the electron beam is modulated using a modulated laser, and the wavefront rotation characteristics of the modulated laser are used to generate a micro-focused electron beam.

[0081] S940: The electron beam that generates micro-focused beams emits coherent radiation light after passing through the radiation undulator 300.

[0082] S950: The distance between the first grating 110 and the second grating 120 is adjusted by the displacement stage 140 to control the pulse width of the coherent radiation light output by the radiation undulator 300.

[0083] According to the control method of the accelerator coherent light source device of this embodiment, by adjusting the distance between the grating pairs, the degree of wavefront rotation of the modulated laser can be controlled, thereby realizing continuous adjustment of the radiation pulse width from a few femtoseconds to hundreds of femtoseconds, which can enhance the flexibility and applicability of the accelerator coherent light source device.

[0084] The accelerator coherent light source device and its control method described in this embodiment can be applied to a lithography system to provide coherent radiation light with the required pulse width for lithography. Therefore, lithography systems including the above-described accelerator coherent light source device are also within the scope of protection of this invention.

[0085] Furthermore, in the above embodiments, the grating pair formed by the first and second gratings enables the modulated laser to possess wavefront rotation characteristics, and the degree of wavefront rotation of the modulated laser is adjusted by changing the distance between the grating pair, thereby adjusting the width of the output pulse. However, the present invention is not limited to this; the modulated laser optical platform can also use a prism pair instead of a grating pair.

[0086] Figure 10 This is another schematic diagram of the modulated laser optical platform in the coherent light source device of the accelerator according to an embodiment of the present invention. Figure 10 In the process, the Gaussian laser passes through the first prism 110' and the second prism 120' in sequence and becomes a wavefront rotating laser.

[0087] The first prism 110' and the second prism 120' are placed symmetrically as shown in the figure. The Gaussian laser beam undergoes refraction and dispersion after passing through the first prism 110', propagates a distance (related to the distance between the two prisms), and then enters the second prism 120', where it undergoes refraction and dispersion again. Similar to the case of grating pairs, the degree of wavefront rotation is related to the geometric parameters of the prism pair (such as the distance between the prisms, the angle of incidence, and the refractive index of the prisms). Specifically, the greater the distance between the prisms, the greater the degree of wavefront rotation.

[0088] Therefore, by adjusting the distance between the first prism 110' and the second prism 120', the degree of wavefront rotation of the modulated laser can also be adjusted, thereby adjusting the width of the output pulse.

[0089] It should be understood that the above description is illustrative and not restrictive. For example, the above embodiments (and / or aspects thereof) can be used in combination with each other. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of the various embodiments of this disclosure without departing from the scope of this disclosure. While the dimensions and types of materials described herein are used to define parameters of the various embodiments of this disclosure, the embodiments are not intended to be restrictive but are exemplary. Many other embodiments will become apparent to those skilled in the art upon reading the above description. Therefore, the scope of the various embodiments of this disclosure should be determined by reference to the appended claims and the full scope of their equivalents.

Claims

1. An accelerator coherent light source device, characterized in that, include: A modulated laser optical platform applies transverse dispersion to the incident laser beam and outputs a wavefront-rotating laser as a modulated laser. A modulation device that uses the modulation laser to modulate the electron beam generated by the accelerator and outputs a clustered electron beam. A radiation undulator provides a gain medium for the clustered electron beam and outputs coherent radiation pulses.

2. The accelerator coherent light source device as described in claim 1, characterized in that, The width of the coherent radiation pulse varies according to the degree of wavefront rotation of the modulated laser output by the modulated laser optical platform.

3. The accelerator coherent light source device as described in claim 1 or 2, characterized in that, The modulated laser optical platform includes a grating pair consisting of a first grating and a second grating arranged in parallel. The degree of wavefront rotation applied by the modulated laser optical platform varies depending on the distance between the first grating and the second grating.

4. The accelerator coherent light source device as described in claim 3, characterized in that, The modulated laser optical platform also includes a displacement stage capable of changing the distance between the first grating and the second grating. The first grating is fixedly installed, and the second grating is installed on the displacement stage.

5. The accelerator coherent light source device as described in claim 4, characterized in that, The modulated laser optical platform also includes a first reflecting mirror. The incident laser beam is diffracted by the first grating and the second grating in succession, and then reflected by the first mirror to the modulation device.

6. The accelerator coherent light source device as described in claim 1 or 2, characterized in that, The modulation device includes a second mirror, a modulator, a magnetic compressor, and a third mirror arranged sequentially along the transmission direction of the electron beam. The modulated laser is incident on the undulator via the second reflector, where it exchanges energy with the electron beam, causing the electron beam to modulate its energy. The modulated laser then exits the modulation device via the third reflector. The magnetic compressor performs density modulation on the energy-modulated electron beam, thereby outputting the clustered electron beam.

7. The accelerator coherent light source device as described in claim 6, characterized in that, The magnetic compressor comprises four dipolar magnets.

8. The accelerator coherent light source device as described in claim 1 or 2, characterized in that, A bending magnet is provided downstream of the radiation undulator, which separates the output coherent radiation pulse from the electron beam.

9. The accelerator coherent light source device as described in claim 1 or 2, characterized in that, The modulated laser optical platform includes a prism pair consisting of a first prism and a second prism arranged symmetrically. The degree of wavefront rotation applied by the modulated laser optical platform varies depending on the distance between the first prism and the second prism.

10. A photolithography system, characterized in that, Includes the accelerator coherent light source device as described in any one of claims 1 to 9.

11. A control method for an accelerator coherent light source device, characterized in that, The accelerator coherent light source device includes a modulated laser optical platform, a modulation device, and a radiation undulator. The control method includes the following steps: An electron beam generated by an accelerator is injected into the modulation device; A laser beam is introduced into the modulated laser optical platform, which applies transverse dispersion to the laser beam and outputs a wavefront rotating laser as a modulated laser. The modulation device uses the modulation laser to modulate the electron beam, causing the electron beam to cluster and be output; and The radiation undulator provides a gain medium for the electron beam output from the modulation device, thereby outputting a coherent radiation pulse.

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