EUV light source generating device
By combining liquid metal spraying with microwave plasma excitation, the high cost and low efficiency of existing EUV light source generation devices have been solved, realizing low-cost and high-efficiency EUV light source generation. This avoids the high cost and discharge electrode ablation problems of laser systems and improves EUV conversion efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2026-03-13
AI Technical Summary
Existing EUV light source generation devices are costly, complex, and inefficient, exhibiting significant energy consumption and electrode ablation issues, resulting in low EUV conversion efficiency.
A method combining liquid metal spraying and microwave plasma excitation is adopted, using room-temperature liquid metal alloys (such as GaInSn) to replace solid tin targets, generating plasma through microwave non-contact energy transfer, and achieving closed-loop control by combining detection components and control modules.
It achieves low-cost, high-efficiency EUV light source generation, reduces equipment costs and energy consumption, avoids the high cost of laser systems and the problem of discharge electrode ablation, and improves EUV conversion efficiency.
Smart Images
Figure CN223993043U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of plasma technology, and in particular to an EUV light source generating device. Background Technology
[0002] Extreme ultraviolet (EUV) light sources are also known as laser plasma light sources. They are mainly used for semiconductor lithography to manufacture chips and are currently the shortest exposure light source for commercial semiconductor lithography.
[0003] In existing technologies, EUV light sources primarily rely on laser plasma technology: a high-power laser bombards tin (Sn) metal droplets ejected from a nozzle at a specific flow rate, with each droplet bombarded twice (i.e., 100,000 laser pulses per second), evaporating them into plasma. EUV light with a wavelength of 13.5 nm is obtained through transitions between energy levels of high-valence tin ions.
[0004] However, the generation of EUV light sources relies on high-power lasers, resulting in significant energy consumption and high system complexity (a carbon dioxide laser has over 450,000 components, with cables exceeding 7,000 meters in length and weighing over 17,000 kilograms), and costs exceeding ten million US dollars. These pain points have greatly driven the exploration and development of alternative technologies. Furthermore, existing laser plasma technologies also suffer from electrode ablation problems and lifespan limitations, resulting in low EUV conversion efficiency (~5%).
[0005] Therefore, how to provide a low-cost, high-efficiency EUV light source generation device and method is a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content
[0006] This invention provides an EUV light source generating device to solve the defects of existing EUV light source generating devices, such as complexity, high cost, and low efficiency, and to achieve low-cost and high-efficiency generation of EUV light sources while ensuring radiation intensity.
[0007] This utility model provides an EUV light source generating device, comprising:
[0008] A vacuum chamber used to maintain a vacuum environment;
[0009] A liquid metal spray generating device, which incorporates a room-temperature liquid metal alloy, is used to spray liquid metal droplets into the vacuum chamber;
[0010] A microwave transmitter is used to apply a microwave field to the vacuum cavity to generate plasma from liquid metal droplets;
[0011] A spectral filtering module is used to extract the extreme ultraviolet light emitted by the plasma.
[0012] According to the EUV light source generating device provided by this utility model, it further includes: a detection component and a control module. The detection component is used to monitor the parameters of the liquid metal droplets generated by the liquid metal spray generating device, the microwave field signal of the microwave transmitter / vacuum cavity, the operating parameters of the vacuum cavity, and the extreme ultraviolet light intensity of the spectral filtering module, to obtain the detection results, and to feed the detection results back to the control module.
[0013] The control module is used to control the corresponding module to make adjustments based on the detection results, so that the detection results are within a preset range.
[0014] According to the EUV light source generating device provided by this utility model, the detection component includes:
[0015] A microwave power meter and a three-dimensional electric field probe array are used to track microwave field distribution in real time.
[0016] Cameras and laser scattering particle size analyzers are used for online analysis of the particle size distribution and atomization concentration of liquid metal droplets;
[0017] Vacuum gauges are used to monitor vacuum environments.
[0018] Flow meter, used to detect the flow rate of liquid metal droplets;
[0019] A spectrometer is used to provide feedback on EUV light intensity and spectral purity.
[0020] According to the present invention, an EUV light source generating device further includes a plasma confinement device, the working end of which is connected to the vacuum cavity, and the plasma confinement device is used to confine the plasma.
[0021] According to the EUV light source generating device provided by this utility model, the detection component further includes a confinement field detection device for detecting the external field generated by the plasma confinement device.
[0022] According to the EUV light source generating device provided by this utility model, the microwave transmitter has an operating frequency of 0.3~30 THz, a power density of ≥1 GW / cm², and a pulse width of ≤100 ns.
[0023] According to the present invention, an EUV light source generating device is provided, wherein the inner wall of the vacuum cavity includes a metamaterial layer, the metamaterial layer being used to prevent corrosion by liquid metal droplets and to enhance the coupling efficiency between the microwave field and the liquid metal droplets.
[0024] According to the EUV light source generating device provided by this utility model, the feed port of the microwave transmitter includes one of a rectangular, coaxial, and circular port.
[0025] According to the EUV light source generating device provided by this utility model, the port mode of the microwave transmitter includes one of the following: transverse electric mode, transverse magnetic mode, transverse electromagnetic mode, numerical mode, and periodic mode.
[0026] According to the present invention, an EUV light source generating device is provided, wherein the liquid metal spray generating device controls the particle size, atomization concentration, and flow rate of the liquid metal droplets required for generation.
[0027] The EUV light source generation device provided by this utility model combines liquid metal spraying technology with microwave plasma excitation, breaking through the path dependence of traditional EUV light sources that rely on lasers or discharges, and has the following beneficial effects:
[0028] (1) Target material innovation: room temperature liquid metal alloy (such as GaInSn) is used to replace solid tin target or xenon gas to solve the problem of high energy consumption in target material transportation and melting in traditional technology.
[0029] (2) Innovative excitation method: Utilize microwave non-contact energy transfer to avoid the high cost of laser systems or the ablation problem of discharge electrodes.
[0030] (3) Low energy consumption: Room temperature liquid metal has fluid properties, which makes it easy to generate micro-nano droplet spray using low-cost atomizing nozzles. Compared with the LDP technology, which uses a high-power laser light source to heat the target material tin vaporization, the equipment cost is lower and the energy consumption is also lower. Compared with solid metal, the surface atoms of liquid metal are loosely arranged, making it easier to be excited by an external field to generate plasma. The microwave field is spatially distributed and has a larger action area, which makes it easier to generate more extreme ultraviolet light. The liquid metal interface has abundant free electrons, which makes it easy to generate high-energy plasma under microwave field excitation, resulting in low energy consumption. By setting the microwave power and working time, as well as the concentration and particle size of the liquid metal spray, the extreme ultraviolet light can be adjusted. The process is simple, controllable, and low-cost, making it easy to commercialize. Attached Figure Description
[0031] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0032] Figure 1 This is a schematic diagram of the EUV light source generating device provided by this utility model.
[0033] Figure label:
[0034] 1. Vacuum chamber; 2. Liquid metal spray generation device; 3. Microwave transmitter; 4. Spectral filtering module; 6. Control module; 7. Plasma confinement device; 51. Microwave power meter and three-dimensional electric field probe array; 52. Camera; 53. Laser scattering particle size analyzer; 54. Vacuum gauge; 55. Flow meter; 56. Spectrometer; 57. Confinement field detection device. Detailed Implementation
[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.
[0036] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0037] The following is combined Figure 1 A structural block diagram describing the EUV light source generating device of this utility model.
[0038] like Figure 1 As shown, this utility model embodiment provides an EUV light source generating device, including a vacuum chamber 1, a liquid metal spray generating device 2, a microwave transmitter 3, and a spectral filtering module 4.
[0039] Vacuum chamber 1 is used to maintain a vacuum environment. Liquid metal spray generation device 2 contains a room-temperature liquid metal alloy and is used to spray liquid metal droplets into vacuum chamber 1. Microwave transmitter 3 is used to apply a microwave field to vacuum chamber 1 to generate plasma from the liquid metal droplets. Spectral filtering module 4 is used to extract extreme ultraviolet light from the plasma radiation.
[0040] It should be noted that under the influence of a microwave field, electrons on the surface of liquid metal are accelerated and gain kinetic energy. These accelerated electrons collide with other liquid metal atoms, causing the outer electrons of those atoms to detach. The newly generated electrons are further accelerated by the microwave field, triggering avalanche ionization and forming plasma, accompanied by specific plasma radiation phenomena. Liquid metals, represented by gallium-based alloys, not only possess fluidity, high electrical / thermal conductivity, and dynamic self-healing properties, but also have the intrinsic ability to generate plasma under stimulation. They can produce plasmas with different properties under various external fields (such as electric fields, electromagnetic fields, and microwave fields).
[0041] Therefore, in this embodiment, a room-temperature liquid metal alloy (such as GaInSn) is selected to replace the solid tin target or xenon gas, solving the problem of high energy consumption in target material transport and melting in traditional technologies. Microwave non-contact energy transfer is used to avoid the high cost of laser systems or the ablation problem of discharge electrodes. At the same time, room-temperature liquid metal has fluid properties, which facilitates the generation of micro-nano droplet spray using low-cost atomizing nozzles. Compared with the LDP technology, which uses a high-power laser light source to heat the target material tin vaporization, the equipment cost is lower and the energy consumption is also lower. Compared with solid metal, the surface atoms of liquid metal are loosely arranged, making it easier to be excited by an external field to generate plasma. The microwave field is spatially distributed, with a larger effective area, which facilitates the generation of more extreme ultraviolet light. The liquid metal interface has abundant free electrons, which facilitate discharge under microwave field excitation to generate high-energy plasma with low energy consumption. By setting the microwave power and working time, as well as the concentration and particle size of the liquid metal spray, the extreme ultraviolet light can be adjusted. The process is simple, controllable, and low-cost, making it easy for commercial production.
[0042] In some feasible embodiments of this utility model, it further includes: a detection component and a control module 6. The detection component is connected to the liquid metal spray generating device 2, the microwave transmitter 3, the vacuum chamber 1, the spectral filtering module 4, and the control module 6, respectively. The detection component is used to monitor the parameters of the liquid metal droplets generated by the liquid metal spray generating device 2, the microwave field signal of the microwave transmitter 3 / vacuum chamber 1, the operating parameters of the vacuum chamber 1, and the extreme ultraviolet light intensity of the spectral filtering module 4, to obtain the detection results, and feed the detection results back to the control module 6. The control module 6 is used to control the corresponding modules to adjust according to the detection results, so that the detection results are within a preset range.
[0043] The liquid metal droplet parameters include droplet size, atomization concentration, and flow rate. Control module 6 adjusts the corresponding modules based on the detection results from the detection components, and when the microwave field signal, liquid metal droplet parameters, vacuum cavity operating parameters, and extreme ultraviolet light intensity are not within the corresponding preset ranges.
[0044] Specifically, the detection components include a microwave power meter and a three-dimensional electric field probe array 51, a camera 52, a laser scattering particle size analyzer 53, a vacuum gauge 54, a flow meter 55, and a spectrometer 56. The microwave power meter and the three-dimensional electric field probe array 51 are used to track the microwave field distribution in real time; the camera 52, in conjunction with the laser scattering particle size analyzer 53, is used to analyze the particle size distribution and atomization concentration of liquid metal droplets online; the vacuum gauge 54 is used to monitor the vacuum environment; the flow meter 55 is used to detect the flow rate of liquid metal droplets; and the spectrometer 56 is used to provide feedback on EUV light intensity and spectral purity.
[0045] In the above embodiments, all components employ vacuum-compatible packaging and electromagnetic interference-resistant design, supporting closed-loop control of the plasma generation process by a synchronous data acquisition instrument. The working ends of the microwave power meter, the three-dimensional electric field probe array 51, the camera 52, the laser scattering particle size analyzer 53, the vacuum gauge 54, the flow meter 55, and the spectrometer 56 are all connected to the vacuum chamber 1. Liquid metal atomized droplets are introduced into the vacuum chamber 1 through the flow meter 55 and the camera 52 in conjunction with the laser scattering particle size analyzer 53. Microwaves emitted by the microwave transmitter 3 are introduced into the vacuum chamber 1 after passing through the microwave power meter and the three-dimensional electric field probe array 51. EUV light generated by the vacuum chamber 1 is introduced into the spectrometer 56 after passing through the spectral filtering module 4. The vacuum gauge 54 is signal-connected to the control module 6, and the control module 6 controls the vacuum level of the vacuum chamber 1 based on the information fed back from the vacuum gauge 54.
[0046] Furthermore, camera 52 is a high-speed microscopic camera.
[0047] In some feasible embodiments of this invention, a plasma confinement device 7 is further included. The working end of the plasma confinement device 7 is connected to the vacuum cavity 1, and the plasma confinement device 7 is used to confine plasma. The detection assembly also includes a confinement field detection device 57, used to detect the external field generated by the plasma confinement device 57. The external field generated by the plasma confinement device 7 is introduced into the vacuum cavity 1 after passing through the confinement field detection device 7.
[0048] Among them, the plasma confinement device 7 uses an external magnetic field, electric field, or electromagnetic field, or multiple fields working together to confine the plasma, which can extend the plasma lifetime and improve the stability of EUV output.
[0049] In some feasible embodiments of this utility model, the inner wall of the vacuum cavity 1 includes a metamaterial layer. The metamaterial layer is used to prevent corrosion by liquid metal droplets and enhance the coupling efficiency between the microwave field and the liquid metal droplets.
[0050] More specifically, the liquid metal is a metal alloy containing tin and liquid at room temperature, preferably gallium-tin alloy, gallium-indium-tin alloy, or gallium-indium-zinc-tin alloy, wherein the mass percentage of tin is ≥10%; the droplet size, atomization concentration, and flow rate of the liquid metal are controlled by the liquid metal spray generating device 2; the droplet size range of the liquid metal is 0.001~1000 μm, and the droplet size error is less than 1%; the concentration is at the ppm level; and the flow rate range is 100 m / s ~ 0.1 m / s.
[0051] Furthermore, the spatial distribution of the magnetron, operating voltage, operating current, microwave frequency, electromagnetic field strength, microwave power, and operating time of the microwave transmitter 3 are adjustable; the operating frequency of the microwave transmitter 3 is 0.3~30 THz, the power density is ≥1 GW / cm², and the pulse width is ≤100 ns; the microwave feed port types include rectangular, coaxial, and circular ports; the port modes include transverse electric mode, transverse magnetic mode, transverse electromagnetic mode, numerical mode, and periodic mode; the microwave power setting range is 10%~100% of the total microwave power.
[0052] In summary, the working method of the EUV light source generation device provided by this utility model is as follows: A vacuum chamber 1 is evacuated, and a vacuum gauge 54 is used to detect whether the vacuum degree of the vacuum chamber 1 has reached a preset value; after the vacuum degree of the vacuum chamber 1 reaches the preset value, the liquid metal spray generation device 2 generates liquid metal micro / nano droplets with a certain flow rate and concentration, and introduces them into the vacuum chamber 1; the flow rate, particle size distribution, and atomization concentration of the liquid metal droplets generated by the liquid metal spray generation device 2 are analyzed online using a flow meter 55, a camera 52, and a laser scattering particle size analyzer 53, and the data is transmitted to the control module 6 in real time; the microwave transmitter 3 is turned on, and microwaves with a certain pulse frequency and power are fed into the vacuum chamber 1, and the spatial distribution position and operating voltage of the magnetron are adjusted accordingly. The operating current, microwave pulse frequency, and electromagnetic field intensity are synchronized with the droplet ejection. The microwave field distribution is tracked in real time using a three-dimensional electric field probe array 51 of a microwave power meter, and the data is transmitted to the control module 6 in real time. The plasma generated by the liquid metal spray in the vacuum cavity 1 is constrained using a plasma confinement device 7, and the confinement strength is detected by a confinement field detection device 57, and the data is transmitted to the control module 6 in real time. After the emitted extreme ultraviolet light passes through the spectral filtering module 4, the EUV intensity is detected by a spectrometer 56 to see if it reaches the preset value, and the data is transmitted to the control module 6 in real time. If the preset value is not reached, the operating parameters of the liquid metal spray generating device 2, the microwave emitter 3, and the plasma confinement device 7 are adjusted by the control module 6, and the above steps are repeated. After the spectrometer 56 detects that the EUV intensity has reached the preset value, it maintains the set operating parameters and continuously outputs stable EUV light.
[0053] Therefore, the EUV light source generating device provided by this utility model replaces the traditional laser plasma with microwave plasma technology, achieving low-cost and high-efficiency generation of EUV light sources while ensuring radiation intensity.
[0054] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model according to the specific circumstances.
[0055] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "method," "specific method," or "some methods," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or method is included in at least one embodiment or method of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or method. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or methods. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or methods described in this specification, as well as the features of different embodiments or methods.
[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. An EUV light source generating apparatus, characterized by comprising: The application relates to a liquid metal plasma EUV light source. The application comprises: a vacuum cavity (1) for maintaining a vacuum environment; a liquid metal spray generating device (2) for spraying liquid metal droplets into the vacuum cavity (1), wherein the liquid metal spray generating device (2) is filled with liquid metal alloy at room temperature; a microwave transmitter (3) for applying a microwave field to the vacuum cavity (1) to generate plasma from the liquid metal droplets; 2. The EUV light source generating device according to claim 1, characterized in that a spectral filtering module (4) for extracting extreme ultraviolet band light of the plasma radiation. The application further comprises: a detection assembly and a control module (6), wherein the detection assembly is used for monitoring parameters of the liquid metal droplets generated by the liquid metal spray generating device (2), a microwave field signal of the microwave transmitter (3) / the vacuum cavity (1), working parameters of the vacuum cavity (1) and extreme ultraviolet band light intensity of the spectral filtering module (4), obtaining detection results and feeding back the detection results to the control module (6); 3. The EUV light source generating device of claim 2, wherein the control module (6) is used for controlling corresponding modules to be adjusted according to the detection results so that the detection results are within a preset range. The detection assembly comprises: a microwave power meter and a three-dimensional electric field probe array (51) for tracing microwave field distribution in real time; a camera (52) and a laser scattering particle size analyzer (53) for analyzing particle size distribution and atomization concentration of the liquid metal droplets on line; a vacuum gauge (54) for monitoring the vacuum environment; a flowmeter (55) for realizing flow rate detection of the liquid metal droplets; 4. The EUV light source generating device of claim 2 or 3, characterized in that a spectrometer (56) for completing EUV light intensity and spectral purity feedback.
5. The EUV light source generating device of claim 4, wherein The application further comprises a plasma confinement device (7) in communication with the vacuum cavity (1), and the plasma confinement device (7) is used for confining plasma.
6. The EUV light source generating device of claim 4, wherein The detection assembly further comprises a confinement field detection device (57) for detecting an external field generated by the plasma confinement device (7).
7. The EUV light source generating device of claim 1, wherein The microwave transmitter (3) has a working frequency of 0.3-30 THz, a power density of greater than or equal to 1 GW / cm2 and a pulse width of less than or equal to 100 ns.
8. The EUV light source generating device of claim 1, wherein An inner wall of the vacuum cavity (1) comprises a super material layer, and the super material layer is used for placing liquid metal droplets to be corroded and enhancing coupling efficiency of the microwave field and the liquid metal droplets.
9. The EUV light source generating device of claim 8, wherein A feed-in port of the microwave transmitter (3) comprises one of a rectangular port, a coaxial port and a circular port.
10. The EUV light source generating device of claim 1, wherein A port mode of the microwave transmitter (3) comprises one of a transverse electric mode, a transverse magnetic mode, a transverse electromagnetic mode, a numerical mode and a periodic mode. The liquid metal spray generating device (2) is used for controlling particle size, atomization concentration and flow of the generated liquid metal droplets.