Extreme ultraviolet light generation system, method, control device, controller and storage medium

Abstract

The present application relates to an extreme ultraviolet light generation system, method, control device, controller, and storage medium. The system includes: an amplifier, at least two first pump lasers, an acousto-optic modulator connected between the lasers and the amplifier; a droplet target generator placed on the output path of the laser pulse output by the amplifier; a position feedback device for obtaining the pre-targeting position and re-targeting position of each droplet target; and a controller connected to the position feedback device, the acousto-optic modulator, and the first pump laser. Based on the aforementioned target positions, the target power corresponding to the pump energy provided by each pump laser to generate a double-peak waveform laser pulse and the on-off time ratio of the acousto-optic modulator are determined; each laser is driven to provide pump energy of the target power, and the acousto-optic modulator is controlled on and off according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and then bombards the droplet target at the aforementioned position to generate extreme ultraviolet light.

Description

Technical Field

[0001] The present application relates to the field of laser technology, and in particular to an extreme ultraviolet light generation system, method, control device, controller and storage medium. Background Art

[0002] With the growing demand for chips, the semiconductor industry has developed rapidly. In the semiconductor manufacturing process, photolithography technology, as a key technology, plays an irreplaceable role. Among them, how to generate extreme ultraviolet light that meets the requirements is the prerequisite for the realization of photolithography technology.

[0003] Traditional technologies for generating extreme ultraviolet light mostly use synchrotron radiation technology, laser plasma technology, discharge plasma technology, and laser-assisted discharge plasma technology. However, the above technologies have problems of self-absorption effect and low efficiency during the generation of extreme ultraviolet light.

[0004] At present, in order to solve the above problem, two driving laser devices are often used to bombard tin droplets to generate extreme ultraviolet light (ie, double-pulse technology), but the production cost of this technical solution is too high. Summary of the Invention

[0005] Based on this, it is necessary to provide an extreme ultraviolet light generation system, method, control device, controller and storage medium that can reduce the cost of extreme ultraviolet light generation in response to the above technical problems.

[0006] In a first aspect, an extreme ultraviolet light generation system is provided, comprising:

[0007] at least two first pump lasers, for providing pump energy for generating double-peak waveform laser pulses;

[0008] an acousto-optic modulator, wherein an input end of the acousto-optic modulator is connected to an output end of the first pump laser in a one-to-one correspondence;

[0009] an amplifier, wherein an input end of the amplifier is connected to an output end of the acousto-optic modulator;

[0010] A droplet target generator is placed on the emission path of the laser pulse output by the amplifier and is used to generate droplet targets;

[0011] A position feedback device is used to obtain the pre-targeting position and re-targeting position of each droplet target;

[0012] A controller, wherein the input end of the controller is connected to the output end of the position feedback device, and the control end of the controller is respectively connected to the acousto-optic modulator and the controlled end of the first pump laser. The controller is used to:

[0013] Obtaining the pre-targeting position and re-targeting position of the droplet target;

[0014] Determining the target power corresponding to the pump energy provided by each first pump laser to generate a double-peak waveform laser pulse and the on-off time ratio of the acousto-optic modulator according to the pre-targeting position and the re-targeting position of the droplet target;

[0015] Each first pump laser is driven to provide pump energy of the target power, and the on-off of the acousto-optic modulator is controlled according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and bombards the droplet target at the pre-targeting position and the re-targeting position, generating extreme ultraviolet light.

[0016] In one embodiment, the amplifier comprises:

[0017] a second pump laser, the second pump laser being used to output pump energy required for amplification;

[0018] A fiber combiner, wherein a first input end of the fiber combiner is connected to the output end of the acousto-optic modulator, and a second input end of the fiber combiner is connected to the output end of the second pump laser. The fiber combiner is used to couple the double-peak waveform laser pulse output by the acousto-optic modulator and the pump energy output by the second pump laser to output an amplified double-peak waveform laser pulse to bombard the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

[0019] In one embodiment, the amplifier further comprises:

[0020] The cladding stripper has an input end connected to an output end of the optical fiber combiner through a double-clad ytterbium-doped optical fiber, and the cladding stripper is used to absorb laser light transmitted in the cladding portion of the double-clad ytterbium-doped optical fiber.

[0021] In one embodiment, the amplifier is a multi-stage amplifier.

[0022] In one embodiment, the amplifier comprises:

[0023] a first-stage amplifier, wherein an input end of the first-stage amplifier is connected to an output end of the acousto-optic modulator;

[0024] a second-stage amplifier, wherein an input end of the second-stage amplifier is connected to an output end of the first-stage amplifier;

[0025] The third-stage amplifier has an input end connected to the output end of the second-stage amplifier.

[0026] In a second aspect, a method for generating extreme ultraviolet light is provided, which is applied to the extreme ultraviolet light generating system in the above embodiment, and the method includes:

[0027] Obtaining the pre-targeting position and re-targeting position of the droplet target;

[0028] Determining the target power corresponding to the pump energy provided by each first pump laser to generate a double-peak waveform laser pulse and the on-off time ratio of the acousto-optic modulator according to the pre-targeting position and the re-targeting position of the droplet target;

[0029] Each first pump laser is driven to provide pump energy corresponding to the target power, and the acousto-optic modulator is controlled to be on and off according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and bombards the droplet target at the pre-targeting position and the re-targeting position, generating extreme ultraviolet light.

[0030] In one embodiment, the method further comprises:

[0031] Obtain the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator;

[0032] Determining the droplet target generation frequency of the droplet target generator according to the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator;

[0033] A driving signal is generated according to the droplet target generation frequency; the driving signal is used to instruct the droplet target generator to generate a droplet target according to the droplet target generation frequency, so that the double-peak waveform laser pulse amplified by the amplifier bombards the droplet target at the pre-target position and the re-target position.

[0034] In a third aspect, an extreme ultraviolet light generation control device is provided, comprising:

[0035] An information acquisition module is used to obtain the pre-targeting position and re-targeting position of the droplet target;

[0036] a data determination module for determining, based on the pre-targeting position and the re-targeting position of the droplet target, a target power corresponding to the pump energy provided by each first pump laser to generate a double-peak waveform laser pulse and a switching time ratio of the acousto-optic modulator;

[0037] The driver module is used to drive each first pump laser to provide pump energy corresponding to the target power and control the on / off of the acousto-optic modulator according to the on / off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and then bombards the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

[0038] In a fourth aspect, a controller is provided, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of any one of the methods in the above embodiments when executing the computer program.

[0039] In a fifth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in any one of the above embodiments are implemented.

[0040] The above-mentioned extreme ultraviolet light generation system, method, control device, controller and storage medium are connected to an acousto-optic modulator. At least two pump lasers are connected to the acousto-optic modulator. The controller obtains the pre-targeting position and re-targeting position of the droplet target in the droplet target generator through a position feedback device connected to it, and determines the target power of the above-mentioned pump laser and the switching time ratio of the acousto-optic modulator based on the obtained position information, so that the acousto-optic modulator outputs a double-peak waveform laser pulse, which is amplified by an amplifier connected to the acousto-optic modulator. After amplification, the laser pulse bombards the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light, thereby reducing the number of laser driving devices and greatly reducing the equipment cost and equipment volume of traditional technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 1 is a schematic structural diagram of an extreme ultraviolet light generating system in one embodiment;

[0043] Figure 2 A schematic diagram of EUV light generation during pre-targeting and re-targeting in one embodiment;

[0044] Figure 3 is a schematic structural diagram of an extreme ultraviolet light generating system in another embodiment;

[0045] Figure 4 1 is a schematic structural diagram of an extreme ultraviolet light generating system in yet another embodiment;

[0046] Figure 5 1 is a schematic flow chart of a method for generating extreme ultraviolet light in one embodiment;

[0047] Figure 6 is a schematic flow chart of a method for generating extreme ultraviolet light in another embodiment;

[0048] Figure 7 is a structural block diagram of an extreme ultraviolet light generation control device in one embodiment;

[0049] Figure 8 Schematic diagram of the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0050] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0052] It will be understood that the terms "first," "second," etc. used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element.

[0053] Spatially relative terms such as "under," "beneath," "beneath," "under," "above," "above," etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, spatially relative terms also include different orientations of the device in use and operation. For example, if the device in the drawings is turned over, the element or feature described as "under" or "beneath" or "beneath" the other elements will be oriented as "above" the other elements or features. Thus, the exemplary terms "under" and "under" can include both upper and lower orientations. In addition, the device can also include alternative orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0054] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intervening element. In addition, the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc., if there is transmission of electrical signals or data between the connected objects.

[0055] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

[0056] In one embodiment, Figure 1As shown, an extreme ultraviolet light generation system is provided, comprising: at least two first pump lasers 102, configured to provide pump energy for generating double-peak waveform laser pulses; an acousto-optic modulator 104, wherein the input end of the acousto-optic modulator 104 is connected to the output end of the first pump laser 102 in a one-to-one correspondence; an amplifier 106, wherein the input end of the amplifier 106 is connected to the output end of the acousto-optic modulator 104; a droplet target generator 108, wherein the droplet target generator 108 is placed on the output path of the laser pulse output by the amplifier 106 and the droplet target generator 108 is configured to generate droplet targets; a position feedback device 110, wherein the position feedback device 110 is configured to obtain a pre-targeting position and a re-targeting position of each droplet target; and a controller 112, wherein the input end of the controller 112 is connected to the output end of the position feedback device 110, and the control end of the controller 112 is respectively connected to the controlled end of the acousto-optic modulator 104 and the first pump laser 102, and the controller 112 is configured to:

[0057] Obtaining the pre-targeting position and re-targeting position of the droplet target;

[0058] According to the pre-targeting position and re-targeting position of the droplet target, the target power corresponding to the pump energy provided by each first pump laser 102 to generate the double-peak waveform laser pulse and the switching time ratio of the acousto-optic modulator 104 are determined;

[0059] Each first pump laser 102 is driven to provide pump energy corresponding to the target power, and the acousto-optic modulator 104 is controlled to be on and off according to the on-off time ratio. The double-peak waveform laser pulse output by the acousto-optic modulator 104 is amplified by the amplifier 106 and then bombards the droplet target at the pre-targeting position and the re-targeting position, generating extreme ultraviolet light.

[0060] The first pump laser 102 may be a semiconductor-pumped solid-state laser, a new type of laser using semiconductor solid-state laser material as its working material. It has the advantages of high efficiency, long life, high beam quality, good stability, and compact and miniaturized structure. The acousto-optic modulator 104 may be an acousto-optic Q-switch, the specific structure and function of which are well known to those skilled in the art and will not be described in detail here. The amplifier 106 is used to amplify the laser pulses input thereto to increase the average power of the laser pulses, thereby achieving the energy required to bombard the liquid droplet target and generate extreme ultraviolet light. The droplet target generator 108 is a device for generating a droplet target. The droplet target may be a tin droplet target or a gadolinium droplet target. When bombarded by the pulsed laser, the droplet targets of these elements become plasmatized, thereby generating extreme ultraviolet light. It should be noted that the droplet target generator 108 includes a cavity for generating the droplet target stream. To ensure that the generated droplet target stream has a relatively stable falling velocity for precise targeting, the cavity must be in a vacuum environment during the droplet target generation process. The position feedback device 110 refers to a device that can obtain the position of the droplet target, and can refer to an image information acquisition and processing device composed of a CCD (Charge-coupled Device) and other electronic components or processor chips. The pre-targeting position and re-targeting position of the droplet target refer to different targeting positions of the same droplet target. Specifically, it can be understood that each droplet target has a certain thickness. For example, during the droplet target's fall, the position where a laser pulse with a fixed emission position is projected to the first fifth of the droplet target's thickness can be set as the pre-targeting position of the droplet target. Furthermore, since the droplet will become larger and form a round cake or bubble shape after pre-targeting, it is only necessary to ensure that the droplet target after pre-targeting does not leave the laser pulse emission position and arbitrarily select any position of the droplet target as the re-targeting position. In some embodiments, the pre-targeting and re-targeting positions of the droplet target can also refer to different positions that the droplet target passes through during its fall. In this case, the emission position of the laser pulse can be adjusted to achieve pre-targeting and re-targeting. The above determination of the pre-targeting and re-targeting positions is merely an example and is not intended to be limiting.

[0061] Specifically, the position feedback device 110 collects image information of the pre-targeting position and re-targeting position of the droplet target. The position feedback device 110 processes the image information to obtain and store the pre-targeting position and re-targeting position of the droplet target. The controller 112 obtains the pre-targeting position and re-targeting position of the droplet target from the position feedback device 110 and determines the target power corresponding to the pump energy provided by the first pump laser 102 to generate the double-peak waveform laser pulse and the switching time ratio of the acousto-optic modulator 104 based on the position information. It should be noted that because the target powers of the first pump lasers 102 are unequal, they are input into the acousto-optic modulator 104 to generate double-peak waveform laser pulses. For example, taking two first pump lasers 102 as an example, one laser has an output power of 10W and the other laser has an output power of 2W. In this case, double-peak waveform laser pulses will be generated. Therefore, the target powers of different first pump lasers 102 are not equal, that is, by determining different target power combinations (or target power ratios), a double-peak waveform laser pulse output without passing through the peak can be achieved. Figure 2 As shown, by controlling the on / off switching of the acousto-optic modulator 104 according to a determined on / off time ratio, the interval time between the two peaks of the double-peak waveform laser pulse is adjusted, so that the output double-peak waveform laser pulse is amplified by the amplifier 106 and strikes the liquid droplet target 202 at the pre-targeting position and the re-targeting position. That is, when the power of the double-peak waveform laser pulse is at the first peak 204, the liquid droplet target 202 is pre-targeted, and when it is at the second peak 206, the liquid droplet target 202 formed into a round pancake shape is re-targeted, thereby generating plasma, i.e., extreme ultraviolet light.

[0062] In the above embodiment, at least two pump lasers are connected to the AOM 104. The controller 112 obtains the pre-targeting position and re-targeting position of the droplet target in the droplet target generator 108 through the position feedback device 110 connected thereto, and determines the target power of the pump laser and the switching time ratio of the AOM 104 based on the obtained position information, so that the AOM 104 outputs a double-peak waveform laser pulse, which is amplified by the amplifier 106 connected to the AOM 104. After amplification, the laser pulse bombards the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light, thereby reducing the number of laser driving devices and greatly reducing the equipment cost and equipment volume of traditional technologies.

[0063] In one embodiment, Figure 3As shown, the amplifier 106 includes: a second pump laser 1062, which is used to output pump energy required for amplification; a fiber combiner 1064, wherein a first input end of the fiber combiner 1064 is connected to the output end of the acousto-optic modulator 104, and a second input end of the fiber combiner 1064 is connected to the output end of the second pump laser 1062. The fiber combiner 1064 is used to couple the double-peak waveform laser pulse output by the acousto-optic modulator 104 and the pump energy output by the second pump laser 1062, and then output an amplified double-peak waveform laser pulse to bombard the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

[0064] The second pump laser 1062 is similar to the first pump laser in the above embodiment and will not be described in detail here. The fiber combiner 1064 may be a pump laser, the specific structure and function of which are well known to those skilled in the art, and the specific model and parameters of which can be set according to actual needs.

[0065] Specifically, the fiber combiner 1064 couples the pump energy output by the second pump laser 1062 and the double-peak waveform laser pulse output by the acousto-optic modulator 104 , thereby increasing the average power of the double-peak waveform laser pulse.

[0066] In one embodiment, Figure 3 As shown, the amplifier 106 further includes: a cladding stripper 1066, the input end of the cladding stripper 1066 is connected to the output end of the fiber combiner 1064 through a double-clad ytterbium-doped fiber, and the cladding stripper 1066 is used to absorb the laser transmitted in the cladding part of the double-clad ytterbium-doped fiber.

[0067] Specifically, during transmission through the double-clad ytterbium-doped fiber, the laser pulses output by fiber combiner 1064 may propagate within the cladding of the optical fiber. This cladding-transmitted laser pulse can interfere with the original output laser pulses. By providing a cladding stripper 1066 at the output end of fiber combiner 1064, these cladding-transmitted laser pulses are filtered out, thereby preventing interference with subsequent EUV light generation.

[0068] In one embodiment, the amplifier is a multi-stage amplifier.

[0069] In one embodiment, Figure 4 As shown, the amplifier includes:

[0070] A first-stage amplifier 402, wherein an input end of the first-stage amplifier 402 is connected to an output end of the acousto-optic modulator 104;

[0071] A second-stage amplifier 404, wherein an input terminal of the second-stage amplifier 404 is connected to an output terminal of the first-stage amplifier 402;

[0072] The third-stage amplifier 406 has an input terminal connected to the output terminal of the second-stage amplifier 404 .

[0073] In the above embodiment, a multi-stage amplifier is provided, and at least three stages of amplifiers are provided to amplify the double-peak laser pulse output by the acousto-optic modulator, thereby improving the amplification factor of the laser pulse to meet the power modulation requirements in different scenarios.

[0074] In one embodiment, Figure 5 As shown, a method for generating extreme ultraviolet light is provided, the method comprising:

[0075] S502: Acquire the pre-targeting position and re-targeting position of the liquid droplet target.

[0076] S504 , determining target powers corresponding to pump energies provided by each first pump laser to generate double-peak waveform laser pulses and a switching time ratio of the acousto-optic modulator according to the pre-targeting position and the re-targeting position of the droplet target.

[0077] In step S506, each first pump laser is driven to provide pump energy of a target power, and the acousto-optic modulator is controlled to be on and off according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and then bombards the droplet target at the pre-targeting position and the re-targeting position, thereby generating extreme ultraviolet light.

[0078] The extreme ultraviolet light generating method in this embodiment corresponds to the extreme ultraviolet light generating system in the above embodiment. The specific method of generating the extreme ultraviolet light can refer to the description of the above embodiment and will not be repeated here.

[0079] In one embodiment, Figure 6 As shown, the method further includes:

[0080] S602: Obtain the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator.

[0081] The frequency of the double-peak waveform laser pulse refers to the number of times the double-peak waveform appears per unit time. In a specific embodiment, the frequency may be 40 kHz.

[0082] S604 , determining the frequency of generating the liquid droplet target of the liquid droplet target generator according to the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator.

[0083] Specifically, by setting the frequency of the double-peak waveform laser pulse to the droplet target generation frequency of the droplet target generator, pre-targeting is performed when the power of the double-peak waveform laser pulse is at the first peak, and re-targeting is performed when it is at the second peak, thereby achieving accurate targeting.

[0084] S606, generating a driving signal according to the droplet target generation frequency; the driving signal is used to instruct the droplet target generator to generate the droplet target according to the droplet target generation frequency, so that the double-peak waveform laser pulse amplified by the amplifier bombards the droplet target at the pre-targeting position and the re-targeting position.

[0085] In the above embodiment, by matching the frequency of generating the droplet target with the frequency of generating the double-peak waveform, a complete targeting is completed simultaneously with the generation of one droplet target, that is, a pre-targeting and a re-targeting are completed, thereby achieving precise targeting.

[0086] In order to describe the solution of this application in more detail, Figure 2 and 4 A detailed description is given, and those skilled in the art can refer to the specific connection relationship. Figure 4 The system includes an acousto-optic modulator 104 (AOM), a first pump laser 102 (LD1 and LD2), a fiber combiner, an amplifier, a gain medium, a controller 112, a droplet target generator 108, and a position feedback device 110. Figure 4 The connection and position setting are carried out under the structure. The gain medium is a double-clad ytterbium-doped double-clad fiber (YDF), which is connected between the acousto-optic modulator 104 and the combiner. In a specific embodiment, the core diameter is 10 microns, the inner cladding diameter is 130 microns, and the effective numerical apertures of the core and the inner cladding are 0.08 microns and 0.46 microns, respectively. The acousto-optic modulator 104 is an acousto-optic Q-switched device with an operating wavelength of 1064 nm; the first pump laser LD1 and the first pump laser LD2 are semiconductor lasers with a central wavelength of 915 nm. They are symmetrically located on both sides of the acousto-optic modulator 104, and are coupled into the gain medium through the combiner and input into the acousto-optic modulator 104. The acousto-optic modulator 104 modulates the input pump energy for generating a double-peak waveform laser pulse and outputs a double-peak waveform laser pulse.

[0087] The amplifier includes a first-stage amplifier 402, a second-stage amplifier 404, and a third-stage amplifier 406. Each amplifier stage includes a second pump laser 1062, a cladding power stripper 1066 (CPS), and a gain medium. For the first-stage amplifier 402, the gain medium is a double-clad ytterbium-doped fiber (YDF) with a core diameter of 20 microns and an inner cladding diameter of 130 microns. For the second-stage amplifier 404, the gain medium is a double-clad ytterbium-doped fiber (YDF) with a core diameter of 50 microns and an inner cladding diameter of 400 microns. For the third-stage amplifier 406, the gain medium is a double-clad ytterbium-doped fiber (YDF) with a core diameter of 200 microns and an inner cladding diameter of 480 microns. Pump lasers LD3, LD4, and LD5 are coupled into the gain medium via a beam combiner. The cladding stripper 1066 is used to filter out the light from the cladding of the double-clad ytterbium-doped fiber (YDF).

[0088] The droplet target generator 108 is set on the projection path of the double-peak waveform laser pulse, wherein the droplet target generation frequency of the droplet target generator 108 is set according to the double-peak waveform laser pulse frequency output by the acousto-optic modulator 104, generating a tin droplet target flow corresponding to the double-peak waveform laser pulse frequency.

[0089] The position feedback device 110 includes a CCD camera, which collects image information of the target position of the droplet in real time through the CCD camera, obtains and stores the position information through the processor of the position feedback device 110, and then transmits the position information to the controller in the oscillator.

[0090] The specific steps for implementing extreme ultraviolet light are as follows:

[0091] Step 1: Based on the pre-targeting and re-targeting positions of the droplet target, the output power of the two pump lasers and the on-off ratio of the acousto-optic modulator are adjusted based on this position information to produce a double-peak waveform laser pulse. In one embodiment, the double-peak waveform laser pulse has a pulse width of 20-30 nanoseconds, a double-peak interval of 20-50 nanoseconds, and a frequency of 40 kHz.

[0092] Step 2: Input the double-peak waveform laser pulse obtained above into a three-stage amplifier for amplification. The energy of the output double-peak waveform laser pulse after amplification can reach 20mJ, thereby reaching the energy required to bombard the target material.

[0093] Step three, outputting the double-peak waveform laser pulse after power amplification to the droplet target generator, so that pre-targeting is achieved when the laser pulse power is at the first peak, and re-targeting is achieved when the laser pulse power is at the second peak, thereby generating plasma extreme ultraviolet radiation, that is, generating extreme ultraviolet light.

[0094] It should be understood that although Figure 5-Figure 6The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 5-Figure 6 At least part of the steps may include multiple steps or multiple stages. These steps or stages are not necessarily performed at the same time, but can be performed at different times. The order of execution of these steps or stages is not necessarily one by one, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0095] In one embodiment, Figure 7 As shown, an extreme ultraviolet light generation control device is provided, comprising:

[0096] A position acquisition module 702 is used to acquire the pre-targeting position and re-targeting position of the droplet target;

[0097] A data determination module 704 is configured to determine, based on the pre-targeting position and the re-targeting position of the droplet target, the target power corresponding to the pump energy provided by each first pump laser to generate the double-peak waveform laser pulse and the on-off time ratio of the acousto-optic modulator;

[0098] The driver module 706 is configured to drive each first pump laser to provide pump energy corresponding to the target power and to control the on / off of the acousto-optic modulator according to the on / off time ratio. This allows the double-peak waveform laser pulses output by the acousto-optic modulator to be amplified by the amplifier and then strike the droplet target at the pre-targeting position and the re-targeting position, generating extreme ultraviolet light.

[0099] In one embodiment, the extreme ultraviolet light generation and control device further includes:

[0100] A frequency acquisition module is used to acquire the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator;

[0101] A frequency determination module, configured to determine a droplet target generation frequency of the droplet target generator according to the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator;

[0102] The signal generating module is used to generate a driving signal according to the droplet target generation frequency; the driving signal is used to instruct the droplet target generator to generate a droplet target according to the droplet target generation frequency, so that the double-peak waveform laser pulse amplified by the amplifier bombards the droplet target at the pre-targeting position and the re-targeting position.

[0103] For the specific limitations of the extreme ultraviolet light generation control device, please refer to the limitations of the extreme ultraviolet light generation method above, which will not be repeated here. The various modules in the above-mentioned extreme ultraviolet light generation control device can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0104] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 8 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for generating extreme ultraviolet light is implemented. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device casing, or an external keyboard, touchpad or mouse.

[0105] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0106] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0107] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0108] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0109] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0110] Throughout this specification, references to terms such as "some embodiments," "other embodiments," and "desired embodiments" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. Although these terms are used interchangeably throughout this specification, they do not necessarily refer to the same embodiment or example.

[0111] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0112] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. An extreme ultraviolet light generation system, characterized in that: include: at least two first pump lasers, for providing pump energy for generating double-peak waveform laser pulses; an acousto-optic modulator, wherein an input end of the acousto-optic modulator is connected to an output end of the first pump laser in a one-to-one correspondence; an amplifier, wherein an input end of the amplifier is connected to an output end of the acousto-optic modulator; a liquid droplet target generator, the liquid droplet target generator being placed on an emission path of the laser pulse output by the amplifier, and being used to generate liquid droplet targets; A position feedback device, the position feedback device is used to obtain a pre-targeting position and a re-targeting position of each of the liquid droplet targets; A controller, wherein the input end of the controller is connected to the output end of the position feedback device, the control end of the controller is connected to the controlled ends of the acousto-optic modulator and the first pump laser respectively, and the controller is used to: Obtaining a pre-targeting position and a re-targeting position of the liquid droplet target; Determining, based on the pre-targeting position and the re-targeting position of the droplet target, a target power corresponding to the pump energy provided by each of the first pump lasers to generate the double-peak waveform laser pulse and a switching time ratio of the acousto-optic modulator; Each of the first pump lasers is driven to provide pump energy corresponding to the target power, and the acousto-optic modulator is controlled to be on and off according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and then bombards the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

2. The extreme ultraviolet light generation system according to claim 1, characterized in that: The amplifier comprises: a second pump laser, wherein the second pump laser is used to output pump energy required for amplification; A fiber combiner, wherein a first input end of the fiber combiner is connected to the output end of the acousto-optic modulator, and a second input end of the fiber combiner is connected to the output end of the second pump laser. The fiber combiner is used to couple the double-peak waveform laser pulse output by the acousto-optic modulator and the pump energy output by the second pump laser to output an amplified double-peak waveform laser pulse, so as to bombard the droplet target at the pre-targeting position and the re-targeting position to generate the extreme ultraviolet light.

3. The extreme ultraviolet light generation system according to claim 2, characterized in that: The amplifier further comprises: A cladding stripper, wherein the input end of the cladding stripper is connected to the output end of the optical fiber combiner through a double-clad ytterbium-doped optical fiber, and the cladding stripper is used to absorb laser light transmitted in the cladding part of the double-clad ytterbium-doped optical fiber.

4. The extreme ultraviolet light generating system according to claim 1, characterized in that: The amplifier is a multi-stage amplifier.

5. The extreme ultraviolet light generating system according to claim 4, characterized in that: The amplifier comprises: a first-stage amplifier, wherein an input end of the first-stage amplifier is connected to an output end of the acousto-optic modulator; a second-stage amplifier, wherein an input end of the second-stage amplifier is connected to an output end of the first-stage amplifier; A third-stage amplifier, wherein the input end of the third-stage amplifier is connected to the output end of the second-stage amplifier.

6. A method for generating extreme ultraviolet light, characterized in that: The extreme ultraviolet light generating system according to any one of claims 1 to 5, wherein the method comprises: Obtaining a pre-targeting position and a re-targeting position of the liquid droplet target; Determining, based on the pre-targeting position and the re-targeting position of the droplet target, a target power corresponding to the pump energy provided by each of the first pump lasers to generate a double-peak waveform laser pulse and a switching time ratio of the acousto-optic modulator; Each of the first pump lasers is driven to provide pump energy corresponding to the target power, and the on-off of the acousto-optic modulator is controlled according to the on-off time ratio, so that the double-peak waveform laser pulse output by the acousto-optic modulator is amplified by the amplifier and then bombards the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

7. The method according to claim 6, characterized in that Also includes: Obtaining the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator; determining a droplet target generation frequency of the droplet target generator according to the frequency of the double-peak waveform laser pulse output by the acousto-optic modulator; A driving signal is generated according to the droplet target generation frequency; the driving signal is used to instruct the droplet target generator to generate a droplet target according to the droplet target generation frequency, so that the double-peak waveform laser pulse amplified by the amplifier bombards the droplet target at the pre-targeting position and the re-targeting position.

8. An extreme ultraviolet light generation and control device, characterized in that: The extreme ultraviolet light generating system according to any one of claims 1 to 5, comprising: An information acquisition module is used to obtain the pre-targeting position and re-targeting position of the droplet target; a data determination module for determining, based on the pre-targeting position and the re-targeting position of the droplet target, a target power corresponding to the pump energy provided by each first pump laser to generate a double-peak waveform laser pulse and a switching time ratio of the acousto-optic modulator; The driving module is configured to drive each of the first pump lasers to provide pump energy corresponding to the target power, and to control the on / off of the acousto-optic modulator according to the on / off time ratio, so that the double-peak waveform laser pulses output by the acousto-optic modulator are amplified by the amplifier and then bombard the droplet target at the pre-targeting position and the re-targeting position to generate extreme ultraviolet light.

9. A controller comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 6 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 6 to 7 are implemented.

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