Extreme ultraviolet radiation generation method, extreme ultraviolet radiation source components and optical system

Abstract

This application provides an extreme ultraviolet (EUV) radiation generation method, an EUV radiation source component, and an optical system. The EUV radiation generation method includes: generating plasma using a magnetic confinement device; injecting a specified heavy metal into the magnetic confinement device under preset injection conditions, causing the specified heavy metal to form an unresolved transition array radiation in the magnetic null region; controlling a magnetic perturbation device to shrink the unresolved transition array radiation into multiple discrete radiation points; and controlling an optical device to collect EUV radiation based on these discrete radiation points when the multiple discrete radiation points meet radiation acquisition conditions. This not only constructs a steady-state magnetically confined plasma environment through the magnetic confinement device but also enables the optical device to perform flexible and safe energy harvesting and beam shaping based on discrete radiation points. This ensures efficient EUV radiation acquisition while improving the operational stability of the EUV radiation source component and the durability of the optical device.

Description

Technical Field

[0001] This application relates to the field of nuclear fusion technology, and in particular to extreme ultraviolet radiation generation methods, extreme ultraviolet radiation source components, and optical systems. Background Technology

[0002] Extreme ultraviolet (EUV) lithography is a core process in advanced semiconductor manufacturing. As a key subsystem of the lithography machine, the output power, stability, and spectral purity of the EUV light source directly determine the output efficiency and imaging quality of the lithography machine.

[0003] Currently, extreme ultraviolet (EUV) radiation is mainly generated using a tin target scheme based on laser plasma. This scheme utilizes a high-power carbon dioxide laser to bombard freely flying molten tin droplets at a frequency of approximately 50 kHz, generating high-temperature plasma to emit EUV radiation. However, this pulsed operation results in an extremely low effective emission duty cycle, with plasma absent most of the time, and is accompanied by severe tin debris contamination, significantly limiting the lifespan of the optical device. Summary of the Invention

[0004] In view of this, embodiments of this application provide a method for generating extreme ultraviolet radiation. One or more embodiments of this application also relate to an extreme ultraviolet radiation source component and an optical system to address the technical deficiencies existing in the prior art.

[0005] According to a first aspect of the embodiments of this application, a method for generating extreme ultraviolet radiation is provided, comprising: Using a magnetic confinement device to generate plasma; When the plasma meets the preset injection conditions, the heavy metal injection device is controlled to inject a specified heavy metal into the magnetic confinement device so that the specified heavy metal forms an unresolved transition array radiation in the magnetic zero point region. The controlled magnetic perturbation device shrinks the unresolved transition array radiation into multiple discrete radiation points; When multiple discrete radiation points meet the radiation acquisition conditions, the optical device is controlled to acquire extreme ultraviolet radiation based on multiple discrete radiation points.

[0006] According to a second aspect of the embodiments of this application, an extreme ultraviolet radiation source assembly is provided, including a magnetic confinement device, a heavy metal injection device, a magnetic disturbance device, and an optical device. Magnetic confinement device used to generate plasma; A heavy metal injection device is used to inject a specified heavy metal into a magnetic confinement device when the plasma meets the preset injection conditions, so that the specified heavy metal forms an unresolved transition array radiation in the magnetic null region. A magnetic perturbation device is used to reduce the unresolved transition array radiation into multiple discrete radiation points; An optical device for collecting extreme ultraviolet radiation based on multiple discrete radiation points, provided that the radiation collection conditions are met at multiple discrete radiation points.

[0007] According to a third aspect of the embodiments of this application, an optical system is provided, including an extreme ultraviolet radiation source assembly as provided in the second aspect.

[0008] The extreme ultraviolet (EUV) radiation generation method provided in one or more embodiments of this application constructs a steady-state magnetically confined plasma environment using a magnetic confinement device. By precisely utilizing the physical characteristics of the magnetic null region, the injected heavy metal is confined within a specific spatial range, efficiently exciting unresolved transition array radiation. This ensures the generation efficiency and spectral purity of EUV radiation from the source. Subsequently, a magnetic perturbation device shrinks the concentrated unresolved transition array radiation into multiple discrete radiation points. This allows the light spread of the light source to be controlled within the collection requirements of the optical device, enabling the optical device to effectively collect EUV radiation of the target output wavelength emitted from each discrete radiation point. This overcomes the limitation of traditional large-volume plasma sources being unusable by photolithography scanners due to excessive light spread. Finally, the optical device can perform flexible and safe energy harvesting and beam shaping based on these dispersed discrete radiation points that meet the radiation collection conditions. While ensuring efficient EUV radiation acquisition, this significantly improves the operational stability of the EUV radiation source components and the durability of the optical device. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of an extreme ultraviolet radiation source component provided in one embodiment of this application; Figure 2 This is a flowchart of an embodiment of an extreme ultraviolet radiation generation method provided in this application; Figure 3 This is a top view of an extreme ultraviolet radiation source assembly provided in one embodiment of this application; Figure 4 This is a poloidal cross-sectional view of an extreme ultraviolet radiation source component provided in another embodiment of this application; Figure 5 This is a schematic diagram illustrating the formation principle of a discrete XPR according to another embodiment of this application; Figure 6 This is an architectural diagram of an optical system provided in one embodiment of this application. Detailed Implementation

[0010] Many specific details are set forth in the following description to provide a full understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of this application; therefore, this application is not limited to the specific embodiments disclosed below.

[0011] The terminology used in one or more embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of the one or more embodiments of this application. The singular forms “a,” “the,” and “the” used in one or more embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” used in one or more embodiments of this application refers to and includes any or all possible combinations of one or more associated listed items. The term “at least one” in one or more embodiments of this application means “one or more,” and “a plurality of” means “two or more.” The term “comprising” is an open-ended description and should be understood as “including but not limiting,” and may include other content in addition to what has been described.

[0012] It should be understood that although the terms first, second, etc., may be used to describe various information in one or more embodiments of this application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first may also be referred to as second without departing from the scope of one or more embodiments of this application, and similarly, second may also be referred to as first. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0013] Furthermore, it should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in one or more embodiments of this application are all information and data authorized by the user or fully authorized by all parties. Moreover, the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0014] First, the terms and concepts involved in one or more embodiments of this application will be explained.

[0015] Plasma is a special state of matter composed of highly ionized gas. When a gas is heated to extremely high temperatures or subjected to a strong electromagnetic field, electrons in atoms or molecules break free from the atomic nucleus, forming freely moving negatively charged electrons and positively charged ions.

[0016] Extreme ultraviolet (EUV) light source: refers to a high-energy electromagnetic radiation generator that operates in the EUV band (wavelength range typically between 10nm and 124nm, with the core wavelength in semiconductor lithography being 13.5nm). Because light in this band is strongly absorbed by air and most substances, it must be generated and transmitted in a high vacuum environment, hence it is also known as "vacuum ultraviolet light".

[0017] Soft X-ray (SXR) sources are electromagnetic radiation sources with wavelengths between extreme ultraviolet light and hard X-rays (usually wavelengths between 0.1 nm and 10 nm, or photon energies between 100 eV and 2000 eV). Unlike hard X-rays, which have extremely strong penetrating power, soft X-rays are more easily absorbed by matter. Their photon energy is "just right," allowing them to interact strongly with essential elements of life (such as carbon, nitrogen, and oxygen) while easily penetrating water (the well-known "water window" band).

[0018] Beyond-EUV (BEUV) light source: refers to the next generation of extreme ultraviolet lithography radiation source with wavelengths located in the transition region between EUV and SXR.

[0019] Laser-Produced Plasma (LPP) light source: It is a light source device that uses a high-power, high-energy laser beam to precisely bombard a specific target material (such as micron-sized molten tin droplets), instantly heating the target material to an extremely high temperature in a very short time, thereby exciting a high-density, high-brightness plasma and radiating extreme ultraviolet or soft X-rays.

[0020] Discharge-Produced Plasma (DPP) light sources: These primarily use high-voltage electric pulses to induce intense arc discharges in the gas or metal vapor between two electrodes. The enormous Joule heat generated by the current instantaneously ionizes the medium, forming a high-temperature, high-density plasma that radiates extreme ultraviolet or soft X-rays.

[0021] Steady-state superconducting tokamak: An advanced toroidal magnetic confinement device designed to explore future clean nuclear fusion energy. It utilizes the zero resistance of magnets at extremely low temperatures to generate a powerful and virtually energy-free steady-state magnetic field, safely suspending and confining high-temperature plasma at hundreds of millions of degrees Celsius in a toroidal vacuum chamber. This overcomes the bottleneck of traditional devices that can only operate in short pulses due to resistance heating, enabling long-term, continuous (i.e., steady-state) operation of the fusion reaction.

[0022] Magnetic null point: This usually refers to the position where the total magnetic field is zero (such as the true zero field point in a stellarator or field inversion configuration). For a tokamak, it refers to the X point, where the poloidal magnetic field is zero, but the circumferential magnetic field still exists.

[0023] Low-temperature superconductors (LTS) are superconducting materials that require extremely low temperatures (typically requiring liquid helium cooling, with a critical temperature generally below 30K) to reach a zero-resistance state. Currently, the most mature low-temperature superconducting materials include niobium-titanium (NbTi) alloys and niobium-tritin (Nb3Sn) compounds.

[0024] High-temperature superconductors (HTS) are a class of superconducting materials with relatively high critical temperatures (usually above the boiling point of liquid nitrogen, around 77K, and sometimes even above 100K). They mainly include ceramic oxides such as yttrium barium copper oxide (YBCO), bismuth strontium calcium copper oxide (BSCCO), and rare-earth barium copper oxide (ReBCO). Compared to low-temperature superconductors, the biggest advantage of high-temperature superconductors is that they can be cooled using inexpensive liquid nitrogen and can withstand extremely high magnetic fields several times, or even ten times, stronger than those of low-temperature superconductors.

[0025] The Lower Hybrid Current Drive System (LHCD) is a core auxiliary system used in magnetic confinement fusion devices, essentially equivalent to an ultra-high-power "microwave oven." This system emits electromagnetic waves of a specific frequency (typically centimeter-wave microwaves) into the high-temperature plasma. Utilizing the interaction between the waves and electrons in the plasma (i.e., Landau damping), energy and directional momentum are efficiently transferred to the electrons. This allows for continuous driving and maintenance of the circumferential plasma current without relying on transformer induction, while simultaneously providing auxiliary heating to the plasma.

[0026] High-Z impurities refer to heavy metals with high atomic numbers (Z) mixed into high-temperature plasma, such as tin (Sn), gadolinium (Gd), terbium (Tb), lanthanum (La), tungsten (W), molybdenum (Mo), xenon (Xe), and bismuth (Bi). They typically originate from sputtering and erosion of the inner wall or divertor material of a tokamak device. Once these heavy element atoms enter plasmas at hundreds of millions of degrees Celsius, they carry away enormous amounts of energy through collisional ionization and radiation (such as bremsstrahlung and linear radiation) due to their large number of extranuclear electrons. This causes a sharp drop in plasma temperature (i.e., the "radiative cooling" effect), severely disrupting the steady-state operation of the fusion reaction.

[0027] X-Point Radiator (XPR): An advanced heat dissipation and heat load management technology applied to the divertor region of a magnetic confinement fusion device.

[0028] X-Point Target Radiator (XPTR): In magnetic confinement fusion devices, this advanced heat flux control technology involves placing secondary X-points, located away from the core plasma, at the divertor legs to stably create high-intensity radiation bands in the region. Utilizing a unique magnetic configuration design, it converts the enormous heat load leaking from the core into light energy through impurity radiation and rapidly dissipates it before reaching the divertor target plate. This significantly reduces the heat load on the target plate surface and effectively avoids the risk of radiative collapse that may occur with traditional heat dissipation methods.

[0029] Unresolved Transition Array (UTA): In high-temperature plasma, numerous spectral lines generated during inner-shell electron transitions between highly dense quantum states within high-Z impurity ions cannot be individually resolved by a spectrometer due to their proximity. They ultimately merge into a broad and strong continuous radiation peak (i.e., an "array") in observation. In the X-point divertor region of a tokamak, this UTA ​​radiation possesses extremely high energy dissipation capabilities, efficiently converting the plasma's thermal energy into light energy for radiation, thereby significantly reducing the thermal load on the target plate and protecting the reactor's inner walls.

[0030] Boundaryless Localized Modes (ELM-free): This refers to the ideal operating state in a magnetically confined nuclear fusion device where edge-localized modes (ELMs), a harmful magnetohydrodynamic instability burst, are completely suppressed or eliminated through specific magnetic field configuration control (such as weak-field magnetic surface operation) or active feedback control. In this state, the high-temperature plasma edge remains stable, and periodic, violent energy and particle ejections no longer occur. This completely avoids the impact and ablation of the divertor target plate and the first wall material by the huge transient heat flow, which is a key physical condition for achieving long-pulse, steady-state, and safe operation of the fusion reactor.

[0031] Resonant magnetic perturbation (RMP) is an advanced magnetic field control technology used in magnetic confinement fusion devices. It actively alters the magnetic topology of the plasma edge (e.g., forming magnetic islands or random magnetic field layers) by placing specialized perturbation coils inside the vacuum chamber and applying tiny three-dimensional magnetic field perturbations of specific moduli and frequencies to the edge of the high-temperature plasma.

[0032] Capillary Porous System (CPS): This refers to a porous media system composed of a large number of interconnected micron- or even nano-sized pores. Its core characteristic lies in its ability to utilize the surface tension of the liquid to generate significant capillary forces, thereby spontaneously and efficiently driving and transporting the liquid working fluid without an external power source.

[0033] The Scrape-Off Layer (SOL) is the open magnetic field plasma region located outside the Last Closed Magnetic Surface (LCFS) in a magnetically confined nuclear fusion device. Since the magnetic field lines in this region directly connect the high-temperature plasma core to the reactor's first wall (such as the divertor target), the SOL acts as a necessary channel and buffer zone for heat, particles, and impurities to escape from the core. Its internal physical processes (such as ion transport and heat dissipation) directly determine the service life of the divertor target and the overall confinement performance of the plasma.

[0034] Sn quasi-closed-loop self-circulation: refers to an efficient recycling and reuse mechanism designed for tin targets in extreme ultraviolet lithography or high-power radiation source systems. Since extreme ultraviolet light sources typically generate plasma by continuously bombarding micron-sized molten tin droplets with high-energy lasers, in order to reduce costs and prevent tin impurities from contaminating precision optical mirrors, in this embodiment, Sn in the liquid metal pool is physically sputtered into the plasma via SOL ions, condenses after magnetic zero-point radiative cooling, and flows back to the liquid metal pool through a capillary structure, forming a quasi-closed-loop self-circulation.

[0035] Intermediate Focus (IF): In precision optical systems such as extreme ultraviolet lithography machines, this refers to a virtual source point formed by a radiation source collector converging the original radiation beam emitted by the plasma. As a crucial optical interface between the light source module and the downstream illumination optical system, it is typically precisely positioned at or near a specific opening in the enclosed structure of the light source module. This ensures the efficient and stable transfer of highly focused radiation energy to subsequent patterning devices (such as photomasks or mirror arrays), thereby guaranteeing the quality and accuracy of the lithographic imaging.

[0036] A field facet mirror (FFM) is a core optical array located at the forefront of the optical path in an extreme ultraviolet (EUV) lithography illumination system. It consists of numerous independent micromirrors. Its primary task is to receive and split the raw light beam from the light source. By precisely controlling the deflection angle of each micromirror, it accurately reflects the light onto the downstream pupil mirror, thereby creating a highly spatially uniform light field distribution at the exposure slit of the photomask.

[0037] Pupil Facet Mirror (PFM): In the illumination system of an extreme ultraviolet lithography machine, this is a core optical component located downstream of the field lens and also composed of a micromirror array. It is responsible for receiving the segmented light beam reflected from the field lens and, through coordinated control of the angle of each micromirror, performing a secondary, precise superposition and shaping of the light propagation direction. This generates any custom illumination pattern (such as ring, dipole, or quadrupole pupil shapes) at the entrance pupil of the projection lens, optimizing the resolution and depth of focus of the lithography image to meet the complex exposure requirements of advanced process chips.

[0038] A pupil mirror array is a dual-array core optical component in total internal reflection illumination systems such as extreme ultraviolet lithography machines, consisting of a field mirror and a pupil mirror. It receives and splits the raw light beam through hundreds to thousands of independently rotatable micromirrors in the field mirror array, and works in conjunction with the downstream pupil mirror array to precisely control and superimpose the light direction. This generates an arbitrary, customizable pupil shape (illumination mode) at the mask exposure slit while ensuring extremely high illumination uniformity.

[0039] The Condenser Mirror Group (CMG) is a core optical component in total internal reflection precision optical systems such as extreme ultraviolet lithography machines. Located at the front end of the illumination optical path, it consists of multiple high-reflectivity aspherical mirrors. Its main function is to receive the raw radiation beam from the central focal point and, through precise reflection and focusing, efficiently transmit and uniformly illuminate the downstream pupil blade mirror array. This ensures efficient light energy utilization while providing a stable and controllable initial light field for the entire illumination system.

[0040] To overcome the limitations of the LPP (Lithography-Produced Plasma) approach, the industry has explored other paths, such as discharge-generated plasma (DPP / LDP), but these are difficult to commercialize due to electrode erosion. While free-electron lasers (FEL) and steady-state microbunching (SSMB) offer considerable power, their maturity remains low due to the massive scale of equipment (hundreds of meters) and extremely high costs. Furthermore, a multi-needle Sn vapor jetting scheme has been proposed, utilizing multiple nozzles to generate independent Sn vapor clusters and excite light emission. However, in this scheme, the positions of the emission points formed by multiple nozzles are inaccurate and randomly drift, resulting in significant spatial non-uniformity of the light source. Since the illumination system of a lithography machine strictly requires the light source to have a single, definite spatial position and controlled light spread, the superposition of these numerous and chaotic independent emission points makes subsequent beam homogenization and optical path design infeasible.

[0041] Based on this, this application provides a method for generating extreme ultraviolet radiation. This application also relates to an extreme ultraviolet radiation source component and an optical system, which will be described in detail in the following embodiments.

[0042] See Figure 1 , Figure 1 The diagram shows a structural schematic of an extreme ultraviolet radiation source assembly according to an embodiment of this application. The extreme ultraviolet radiation source assembly 100 includes a magnetic confinement device 102, a heavy metal injection device 104, a magnetic disturbance device 106, and an optical device 108. Magnetic confinement device 102, used to generate plasma; The heavy metal injection device 104 is used to inject a specified heavy metal into the magnetic confinement device 102 when the plasma meets the preset injection conditions, so that the specified heavy metal forms an unresolved transition array radiation in the magnetic zero point region. The magnetic perturbation device 106 is used to shrink the unresolved transition array radiation into multiple discrete radiation points; Optical device 108 is used to collect extreme ultraviolet radiation based on multiple discrete radiation points when the radiation collection conditions are met.

[0043] It should be noted that a magnetic confinement device refers to a physical device that uses a strong magnetic field to restrict and confine the motion of high-temperature plasma. Magnetic confinement devices include, but are not limited to, any one of tokamak, stellarator, magnetic mirror, field inversion configuration, and anti-field pinch. The tokamak can be a toroidal tokamak or a spherical tokamak. Magnetic confinement devices can generate and stabilize plasma, providing the necessary high-temperature environment for the excitation of heavy metal elements, while protecting the inner walls from direct high-temperature ablation.

[0044] A heavy metal injection device is an actuator used to precisely control the entry of a specified heavy metal into the magnetic zero-point region at a specific time and at a specific rate. Since the specified heavy metal is usually a high-Z impurity, the heavy metal injection device can also be called a high-Z impurity supply system.

[0045] A magnetic perturbation device is a control component used to apply magnetic field fluctuations of a specific frequency or amplitude to change the particle distribution or radiation characteristics inside a plasma; it can also be called a circumferential symmetry breaking device. A magnetic perturbation device can disrupt the original continuity or concentration of radiation, shrinking the originally circumferentially continuous unresolved transition array radiation (also known as the X-point radiation band) into multiple discrete radiation points, ensuring that the light spread of each discrete radiation point meets the collection requirements of the optical device.

[0046] An optical device refers to a beam collection, transmission, and imaging system designed for the extreme ultraviolet (EUV) band. An optical device can be a single-port optical extraction system or a multi-port optical extraction system. When multiple discrete radiation points meet the radiation acquisition conditions, the shutter of the output port in the optical device can be opened, allowing EUV radiation to be output through the optical device.

[0047] Preset injection conditions refer to a set of thresholds for a series of plasma state parameters used to determine whether to initiate the injection of a specified heavy metal during the extreme ultraviolet radiation generation process. These parameters include plasma reaching a certain temperature and density. If the plasma meets the preset injection conditions, it means that the specified heavy metal can be efficiently ionized and generate the expected radiation, thereby avoiding fuel waste or plasma extinction caused by ineffective injection.

[0048] Radiation acquisition conditions refer to the standards used to determine whether discrete radiation points are in a state suitable for reception by optical devices. They typically involve indicators such as the electron temperature, spatial location, luminescence intensity, duration, and spectral purity of the discrete radiation points.

[0049] Extreme ultraviolet (EUV) radiation refers to high-energy electromagnetic radiation in the electromagnetic spectrum that lies between far ultraviolet and hard X-rays, specifically encompassing both the EUV and soft X-ray bands. With its extremely short wavelength and high photon energy, EUV radiation can not only overcome the optical diffraction limit, enabling the depiction of nanoscale intricate circuit patterns in semiconductor lithography, but also possesses extremely strong penetration and microscopic detection capabilities. It is widely used in fields such as precise observation of the internal microstructure of materials, material composition analysis, and high-precision non-destructive testing.

[0050] The scheme of this application constructs a steady-state magnetically confined plasma environment using a magnetic confinement device. By precisely utilizing the physical characteristics of the magnetic null region, the injected heavy metal is confined to a specific spatial range, efficiently exciting unresolved transition array radiation. This ensures the generation efficiency and spectral purity of extreme ultraviolet (EUV) radiation from the source. Subsequently, a magnetic perturbation device shrinks the concentrated unresolved transition array radiation into multiple discrete radiation points. This allows the light spread of the light source to be controlled within the collection requirements of the optical device, enabling the optical device to effectively collect EUV radiation of the target output wavelength emitted by each discrete radiation point. This overcomes the limitation of traditional large-volume plasma sources being unusable by photolithography scanners due to excessive light spread. Finally, the optical device can perform flexible and safe energy harvesting and beam shaping based on these dispersed discrete radiation points that meet the radiation collection conditions. While ensuring efficient EUV radiation acquisition, this significantly improves the operational stability of the EUV radiation source components and the durability of the optical device.

[0051] In one embodiment of this application, the magnetic confinement device includes a tokamak, which includes a vacuum chamber, a magnet, and a current driver. A vacuum chamber is used to contain plasma; Magnets are used to generate magnetic fields to confine plasma in a vacuum chamber. Current driver, used to drive current in plasma.

[0052] It should be noted that the vacuum chamber is an annular sealed cavity in a tokamak, providing a pure "container" for the plasma, preventing ultra-high temperature substances from directly contacting and burning the chamber walls, and serving as the working cavity for plasma discharge, heating, and high-Z impurity injection radiation.

[0053] Magnets are used to generate strong magnetic fields to control the movement and shape of plasma produced by a tokamak. Magnets can typically be metal coils (e.g., copper coils) or superconducting coils. Using superconducting coils allows for zero resistance at low temperatures, improving the stability and efficiency of the magnetic field. Magnets may include circumferential field coils, poloidal field coils, and, if necessary, a central solenoid.

[0054] A current actuator is a device that uses electromagnetic waves of a specific frequency (i.e., low-hybrid waves) to interact with the plasma in a tokamak, thereby driving a non-inductive steady-state circumferential current within the plasma, such as an LHCD system. In one embodiment of this application, the operating frequency of the LHCD system is set between 2 GHz and 8 GHz, the parallel refractive index of its injected wave is controlled within the range of 1.6 to 2.5, and the absorbed power of the LHCD system is not less than 0.5 MW, to ensure that sufficient energy can be provided to the tokamak to effectively maintain steady-state non-inductive current drive.

[0055] In practical applications, magnets can generate steady-state circumferential magnetic fields ranging from 1T to 10T (this range is for illustrative purposes only and not a limitation on magnet performance). To ensure the safety and reliability of the magnet under long-term steady-state operation, the magnet design preferably has a critical current margin of not less than twice the critical current to prevent quenching. Furthermore, the selection of superconducting materials for the magnet offers great flexibility: mature and currently very low-cost low-temperature superconducting materials (such as NbTi, Nb3Sn, Nb3Al, MgB2, etc.) can be used, as can high-temperature superconducting materials with higher magnetic field capabilities and wider temperature windows (such as ReBCO / YBCO second-generation high-temperature superconducting tapes, Bi-2223, Bi-2212, etc.), other superconducting materials with critical temperatures not lower than 4K, and any combination of the above materials (such as hybrid magnet configurations of low-temperature and high-temperature superconducting materials). When using low-temperature superconducting materials, the operating temperature can be selected from 1.8K to 7K, and the circumferential magnetic field (B_T) typically operates from 2T to 5T. When using high-temperature superconducting materials, the operating temperature can be selected from 20K to 77K (including but not limited to operation at 77K in the liquid nitrogen temperature range), and the circumferential magnetic field typically operates from 4T to 12T. This application does not limit the material selection for the magnet; any magnet capable of bearing the required magnetic field and maintaining steady-state operation can be used.

[0056] Furthermore, in terms of plasma configuration, the plasma can be controlled within a low-performance range, thereby reducing initial investment costs while ensuring steady-state operation of the extreme ultraviolet radiation source components. (Examples include: large radius R≈0.6m, magnetic field strength B≈3T, plasma current I_p≈300KA, power-to-volume ratio P / V≤8MW / m³, and core electron temperature Te≤3keV). This application does not impose specific numerical limitations on the low-performance range.

[0057] By employing the scheme of this application embodiment, a highly controllable magnetic confinement environment is constructed through the precise coordination of a vacuum chamber, a magnet, and a current driver. This design not only achieves stable confinement and heating of plasma under extreme conditions, but also lays a solid physical and engineering foundation for the subsequent efficient output of extreme ultraviolet radiation (such as extreme ultraviolet or soft X-rays) through high-Z impurity radiation.

[0058] In one embodiment of this application, the heavy metal injection device includes at least one of a vapor nozzle injection device, a liquid metal pool, a laser ablation device, a gas valve injection device, and a solid particle injection device.

[0059] It should be noted that the heavy metal injection device can introduce at least one high-Z impurity selected from tin, gadolinium, terbium, lanthanum, tungsten, molybdenum, xenon, bismuth and combinations thereof into the plasma, so that a high-Z impurity cloud of the high-Z impurity is formed at the plasma boundary and near point X. The inner-shell electrons of the high-ionization state radiative transition form the UTA emission band in the wavelength λ0∈[2nm,15nm].

[0060] A vapor nozzle injection device is a fluid transport system that uses high-pressure vapor or gas as a carrier to precisely inject liquid or gaseous heavy metal elements into a vacuum chamber plasma in the form of atomization or jet. The vapor nozzle injection device includes M vapor nozzles (M≥N, where N is the number of discrete X-point radiators) arranged circumferentially along the vacuum chamber. Each vapor nozzle can be independently configured with a high-Z impurity vapor source, a flow valve, and an aiming mechanism. The circumferential position of the vapor nozzles matches the circumferential position of the discrete X-point radiators (D-XPRs), ensuring that the high-Z impurity vapor supply is uniform in the circumferential direction, while UTA radiation is concentrated at the D-XPR position. The aiming mechanism of each vapor nozzle ensures that the vapor molecule trajectory is approximately aligned with the upstream magnetic surface of the corresponding D-XPR, accelerating ionization and radiation establishment. For example, a tin vapor nozzle can be equipped with an electron beam or laser preheating element to ionize the first batch of tin atoms to Sn during the startup phase. 2+ To Sn 4+ To accelerate the establishment of XPR.

[0061] A liquid metal tank is a storage container that keeps heavy metals in a molten liquid state at high temperatures. The liquid metal tank can be located in the target plate area of ​​a divertor or in a separate inner wall cavity, and contains liquid high-Z impurities (Sn, Sn alloys, or other liquid metals suitable for the operating temperature); the operating temperature of the liquid surface can be between the melting point of the specified heavy metal +50K and the corresponding vapor pressure ≤10K. -2 The temperature limit is within Pa. The liquid metal pool may also contain a capillary structure to confine the specified liquid heavy metal and achieve capillary reflux; the main mechanism for high-Z impurities to enter the plasma is a cascade of SOL ion physical sputtering and metal ion self-sputtering, and is usually not thermal evaporation. Furthermore, in one embodiment of this application, the liquid metal pool can simultaneously serve as at least one of the following: a high-Z impurity incident source, a divertor target, and an energy-to-radiation converter. The liquid metal pool supplies high-Z impurities to the plasma through a sputtering mechanism, and the high-Z impurities are ionized to a high-charge state in the plasma near point X, generating UTA radiation.

[0062] It is worth noting that the net metal consumption of the liquid metal pool is extremely low, enabling highly efficient quasi-closed-loop self-circulation. The vast majority of tin atoms can be directly condensed and returned to the liquid metal pool during radiation cooling. Even if a small amount of neutral tin atoms escape from the light emission port, they will be intercepted and deposited by the buffer gas or the baffle on the outside of the multilayer film collecting mirror; the vapor nozzle injection device only needs to replenish them in small amounts in real time. This design does not impose consumption limitations on the steady-state operation of the extreme ultraviolet radiation source components; according to estimates, at an extreme ultraviolet light output power of 10kW, its net consumption rate is even less than 1 gram / hour.

[0063] In practical applications, a specific heavy metal can be flexibly selected based on the target output wavelength, thereby constructing a highly intelligent self-regulating closed loop. For example, when the target output wavelength is 13.5 nm, tin is the preferred heavy metal, with the temperature controlled between 550 K and 900 K; if the target output wavelength is 6.5 nm to 6.7 nm, Sn-Gd or Sn-Tb eutectic alloys can be used; if the target output wavelength is 4 nm to 7 nm, the low-melting-point tin pool can be used solely for divertor heat dissipation, with tungsten sputtered through the divertor plate and injected via multiple vapor nozzles. Based on this, feedback control of the tin incident rate can form a self-regulating closed loop: once the target heat flux increases, the ion energy and flux of SOL will increase accordingly, leading to an automatic increase in the tin sputtering rate; the increased sputtering rate directly increases the radiation power at point X, which in turn rapidly reduces the target heat flux. The time constant of this closed loop can be controlled to be less than 10 times the plasma energy confinement time, thereby ensuring that the entire extreme ultraviolet radiation source assembly can achieve rapid and stable self-balancing when faced with heat load fluctuations.

[0064] Laser ablation equipment refers to a precision injection device that uses a high-energy-density pulsed laser beam to bombard a heavy metal solid target, causing its surface to instantly vaporize, ionize, and eject plasma plumes.

[0065] A gas valve injection device is a fluid control system that uses the mechanical action of a precision valve to control the injection of a specified heavy metal vapor into a vacuum chamber at a specific time, flow rate, and pressure.

[0066] Solid particle injection device refers to a mechanical delivery system that processes heavy metals into micron-sized powders or tiny particles and accelerates them into plasma using high-speed gas or mechanical centrifugal force.

[0067] In one embodiment of this application, a heavy metal injection device includes both a vapor nozzle injection device and a liquid metal pool, and the two work together: the liquid metal pool can serve as the main power source for steady-state operation, relying on passive sputtering to maintain extremely low net consumption; while the vapor nozzle injection device undertakes the tasks of pre-ionization during startup, fine adjustment during steady-state operation, and redundancy backup of the system. Specifically, during the startup phase of the extreme ultraviolet (EUV) radiation source assembly, high-Z impurity vapor is actively injected via a vapor nozzle injection device to pre-ionize and form the X-point radiator. During the steady-state operation phase, a liquid metal pool is primarily supplied via SOL ion sputtering. Specific heavy metals in the liquid metal pool condense and reflux after radiation cooling, forming a quasi-closed loop with extremely low net consumption. During steady-state operation, the vapor nozzle injection device also serves as a fine-tuning path and redundant backup, allowing for independent correction and balancing of each D-XPR radiation intensity by adjusting the instantaneous flow rate of one or more nozzles. The sum of the impurity incident amounts from the liquid metal pool and the vapor nozzles constitutes the total impurity source rate of the EUV radiation source assembly, and its allocation ratio can be dynamically adjusted between 0:100% and 100%:0. This complementary supply mode not only ensures rapid response and precise control of the radiation source under different operating conditions but also significantly improves the reliability and fault tolerance of the entire EUV radiation source assembly under long-pulse or steady-state operation.

[0068] In one embodiment of this application, a liquid metal pool with a capillary porous media structure is used as a heavy metal injection device in the divertor region. The working mode of the liquid metal pool is highly adaptable to the target output wavelength: when the target output wavelength is 13.5 nm, a tin pool (600 K to 800 K) is used; when the target output wavelength is 6.7 nm, it switches to a tin-gadolinium (Sn-Gd) eutectic or Gd single-element liquid pool; when the target output wavelength is 4 nm to 7 nm, a tungsten divertor plate is used to directly supply the source. The liquid metal pool does not rely on high-temperature evaporation, but relies on the physical sputtering of scraped layer ions (such as deuterium sputtering at 100 eV to 500 eV with an incident yield of about 0.02 to 0.07) and the metal self-sputtering cascade effect (sputtering at 200 eV with an incident yield ≥ 1, forming a self-sustaining avalanche) to release impurities. After these sputtered metal atoms enter the plasma, they are ionized to a high-charge state in the region near the X point and emit extreme ultraviolet or soft X-rays through UTA transitions; the vapor shielding layer itself converts part of the target plate's heat flow into low-energy radiation, while also protecting the target plate.

[0069] In one embodiment of this application, M vapor nozzles uniformly arranged along the circumferential direction of the tokamak are used as a heavy metal injection device. This method achieves spatial homogenization of the heavy metal supply and highly concentrates the radiation energy at the D-XPR detection point. When expanding multi-wavelength applications, vapor nozzles located at different circumferential positions can be configured to inject different heavy metals. This distributed injection strategy breaks the single-band limitation, allowing different D-XPRs to exist simultaneously in the same plasma and emit UTA radiation of different bands. N sets of multilayer film collecting mirrors are configured as high-reflectivity combinations for corresponding bands, thus enabling the same extreme ultraviolet radiation source component to flexibly output multiple different bands of extreme ultraviolet radiation simultaneously, greatly improving the flexibility and functionality of the extreme ultraviolet radiation source component in multicolor radiation source applications.

[0070] It is worth noting that, by abandoning the traditional multi-needle spraying of tin vapor directly as a light source, this embodiment uses an XPR / XPTR formed by magnetically confined plasma as a single deterministic volume light source. Its emission position is geometrically precisely locked by the tokamak magnetic field, exhibiting millimeter-level long-term stability. In this architecture, the vapor nozzle injection device serves only as a tin atom supply mechanism. After entering the plasma, the ejected tin atoms, under the combined influence of magnetic field confinement and plasma dynamics, ultimately converge near point X to form a unified radiator. The vapor nozzle itself does not act as a light-emitting point, thus achieving a high degree of controllability and stability in the spatial distribution of the light source.

[0071] By applying the solution of this application embodiment and configuring at least one of the above-mentioned heavy metal injection devices, flexible and precise control over the composition, density, and spatial distribution of impurities in the plasma is achieved, thereby ensuring that the specified heavy metal enters the plasma at the expected rate and in the expected form. This not only provides a stable material basis for generating extreme ultraviolet radiation in a specific band, but also greatly improves the adaptability and reliability of the extreme ultraviolet radiation source components in response to different experimental requirements and radiation source upgrades.

[0072] In one embodiment of this application, the magnetic disturbance device includes at least one of a radial current bar array, a resonant magnetic disturbance saddle coil group, a circumferential magnetic field ripple modulation coil, and a ferromagnetic insert.

[0073] It should be noted that a radial current bar array refers to an array-type magnetic field generator consisting of multiple current bars discretely arranged radially around the tokamak. The radial current bar array contains 2N current bars, with each pair symmetrically arranged on either side of a corresponding D-XPR position. This enhances the radial magnetic perturbation at each target circumferential position while canceling out the perturbation between adjacent target positions. These current bars pass radially through the external magnet of the vacuum chamber, exciting a local radial magnetic field perturbation sufficient to form a D-XPR on the X-point radiation band by carrying a DC current. As a typical, but not limiting, parameter range, the DC current of the current bars can be from 5kA to 25kA, and the generated local radial magnetic field perturbation δB_r is not less than 5mT. The specific values ​​required for actual operation depend on the actual geometry of the extreme ultraviolet radiation source assembly and the plasma parameters.

[0074] A resonant magnetic perturbation saddle coil assembly is a coil system designed in a saddle shape (fitting the curved surface of the toroidal vacuum chamber of a tokamak) to generate a resonant magnetic field of a specific modulus. By applying a three-dimensional magnetic field perturbation of a specific modulus to the plasma edge, the resonant magnetic perturbation saddle coil assembly disrupts the circumferential symmetry of the plasma, generating circumferential inhomogeneity in the X-point radiation band, forming a D-XPR discrete radiation point.

[0075] A circumferential magnetic field ripple modulation coil is an auxiliary coil arranged circumferentially along the tokamak to superimpose tiny periodic fluctuations (i.e., "ripples") onto the originally smooth and uniform circumferential magnetic field. By superimposing periodic perturbations onto the circumferential magnetic field to disrupt the circumferential symmetry of the plasma, UTA radiation can be localized and concentrated at specific locations, forming discrete radiation points.

[0076] Ferromagnetic inserts are solid components made of ferromagnetic materials such as iron, cobalt, and nickel. They are inserted into the vacuum chamber of a tokamak or placed near a poloidal field (PF) coil to passively change the local magnetic field distribution by utilizing their high magnetic permeability.

[0077] In one embodiment of this application, radial current bars or equivalent non-axisymmetric magnetic perturbation sources can be arranged at N (2≤N≤8) positions along the circumference of the vacuum chamber. This actively modulates the magnetic field topology, precisely shrinking and converging the originally continuously distributed annular X-point radiation band (i.e., unresolved transition array radiation, with a circumference of approximately 377cm) along the vacuum chamber into N millimeter-scale discrete radiation points. The effective luminous area of ​​each D-XPR meets the light spread requirements of the optical device (preferably, the poloidal and circumferential dimensions of each D-XPR do not exceed 50mm, more preferably not exceeding 20mm). This design, which transforms continuous radiation into highly localized point sources, significantly reduces the geometric light spread of the light source, thereby meeting the stringent constraints of extremely ultraviolet lithography scanners regarding extremely high brightness and specific spatial coherence of the light source.

[0078] By applying the scheme of this application embodiment and configuring at least one of the above-mentioned magnetic perturbation devices, multi-dimensional active control of the topological structure of the tokamak plasma magnetic field and the motion state of particles is realized, which greatly enhances the stability and robustness of the extreme ultraviolet radiation source component operation.

[0079] In one embodiment of this application, the extreme ultraviolet radiation source component operates in a boundless local mode state, which is maintained based on at least one of improved constraint mode, quiet high constraint mode, and edge local mode suppression.

[0080] It should be noted that low-confinement mode (L-mode) refers to a basic operating state of plasma, characterized by relatively low energy and particle confinement, with no significant transport barriers forming at the edge regions. In this mode, the temperature and density gradients at the plasma edge are relatively gentle, and heat and particles dissipate outward relatively smoothly and continuously, thus preventing the accumulation of sufficient pressure to trigger a violent ELM burst. Low-confinement mode inherently does not produce ELM and naturally exists in a boundless localized mode state without the need for additional active control measures.

[0081] Improved confinement mode (I-mode) refers to an advanced operating state between low-confinement and high-confinement modes. Its core feature is the separation of "energy confinement" and "particle confinement." In I-mode, a barrier is formed at the plasma edge to prevent heat loss, but at the same time, channels are retained for particles to escape smoothly. Because particles can escape smoothly, the pressure gradient at the edge will not accumulate indefinitely, thus physically suppressing the generation of ELM (Elastic Elastic Membrane).

[0082] Quiet H-mode refers to an operating state in which edge harmonic oscillations are generated at the plasma edge, and the edge pressure gradient is continuously maintained below the ELM trigger threshold, thereby achieving steady-state operation without ELM.

[0083] Edge local mode suppression (ELM Suppression) refers to the self-suppression of ELM caused by the upward shift of D-XPR to a region above point X.

[0084] The solution applied in this application maintains the no-boundary local mode state by employing at least one of improved confinement mode, quiet high-confinement mode, and edge local mode suppression. This physically avoids the severe plasma edge surges caused by periodic ELM bursts in traditional high-confinement modes, thereby completely eliminating the resulting 5% to 50% shot-to-shot radiation power fluctuations and ensuring high stability and repeatability of the extreme ultraviolet radiation source output power. This stable operating state not only greatly protects the divertor target plate, first wall material, and expensive optical devices from thermal erosion and damage, significantly extending the service life of core components, but also ensures high stability of the radiation source power output, avoiding spectral fluctuations caused by severe plasma jitter, and providing a continuous, reliable, and high-quality extreme ultraviolet light source for lithography or detection applications.

[0085] In one embodiment of this application, the optical device includes multiple sets of multilayer film collecting mirrors and light-emitting ports corresponding to the multilayer film collecting mirrors, with each multilayer film collecting mirror corresponding to a discrete radiation point.

[0086] It should be noted that multilayer film collecting mirrors are special reflectors on a precision optical substrate with alternating layers of nanoscale thin films (such as alternating molybdenum / silicon layers) for efficient reflection of extreme ultraviolet (EUV) or soft X-rays. Each set of multilayer film collecting mirrors corresponds to a discrete radiation point, and each guides the EUV radiation of the target output wavelength emitted by it to an independent light-emitting port. The reflection band of the multilayer film coating matches the X-ray radiation band.

[0087] An output port refers to a physical channel or window on an optical device that is specially reserved to allow extreme ultraviolet radiation to pass through the vacuum cavity wall and reach downstream equipment, such as an EUV lithography port.

[0088] By employing the scheme of this application embodiment, and using multiple sets of multilayer film collecting mirrors and light-emitting ports that correspond one-to-one with discrete radiation points, efficient, independent, and precise extraction of extreme ultraviolet radiation is achieved. This "point-to-point" dedicated optical path design not only improves photon collection efficiency and effectively avoids optical crosstalk and excessive light spread between multiple light sources, but also provides downstream equipment with spatially clear, spectrally pure, and highly stable extreme ultraviolet radiation.

[0089] In one embodiment of this application, an intermediate focus module is provided on the light output port. The intermediate focus module includes a differential pump, a magnetic deflection plate, a gas injection port, and a shutter. Differential pumping unit is used to maintain the vacuum pressure difference between the light output port and the optical path; Magnetic deflection plates are used to deflect charged particles traveling from the plasma direction. Gas injection port, used to inject buffer gas to intercept neutral atoms of a specified heavy metal; The shutter is used to control the on / off state of extreme ultraviolet radiation.

[0090] It should be noted that differential pumping components refer to vacuum system components that establish and maintain a specific pressure gradient (pressure difference) between two interconnected vacuum regions through multi-stage vacuum chambers and the principle of gas throttling.

[0091] A magnetic deflector is a physical deflection device that uses the principle of electromagnetic fields to change the trajectory of charged particles (such as ions and electrons) by applying a specific magnetic field. It can be arranged along the EUV optical path. The magnetic deflector can act as a "particle filter," intercepting and deflecting high-energy charged particles and vapors traveling from the plasma direction, ensuring that only uncharged extreme ultraviolet photons can pass through in a straight line, thereby protecting the back-end optical components from damage caused by ion bombardment.

[0092] The gas injection port is a fluid control interface for precisely injecting trace amounts of buffer gas (such as hydrogen or low-Z gas) into a specific vacuum chamber. Although magnetic deflection plates can block charged particles, there are also a large number of uncharged neutral heavy metal atoms (such as neutral tin atoms) in the plasma, to which magnetic fields have no effect. Specific buffer gases can be injected through the gas injection port. These buffer gas molecules collide with the high-speed flying neutral heavy metal atoms, dissipating their kinetic energy, slowing them down, and ultimately depositing them on the chamber wall, preventing them from continuing to fly forward and contaminating the optical lenses.

[0093] A shutter is a mechanical or photoelectric control device that can physically open or close a light beam path at millisecond-level speeds, such as a rotating blade shutter with a maximum switching frequency of at least 200Hz. In lithography machines, during wafer alignment, wafer replacement, or when the light source is unstable, it is necessary to immediately cut off the extreme ultraviolet (EUV) light irradiation. The shutter acts like an extremely sensitive "light switch," receiving instructions from the control system and inserting or removing itself from the light path in a very short time to precisely control the on / off state of EUV radiation.

[0094] For example, the optical device can adopt a standard intermediate focal point mode, that is, each D-XPR is independently configured with a dedicated multilayer film collecting mirror. Each set of multilayer film collecting mirrors can be an ellipsoidal multilayer film reflector, which precisely focuses the 13.5nm radiation reflected from each point to the intermediate focal point. Then, it is transmitted to the lithography scanner through the intermediate focal point module, which includes a differential pump, a magnetic deflection plate, a gas injection port, and a shutter. This design not only achieves the efficient multiplexing capability of a single tokamak to supply light to K scanners (2≤K≤N) simultaneously, but also ensures seamless compatibility and plug-and-play functionality with existing lithography equipment because it adopts the universal interface specification of commercial EUV scanners. The first focus of the ellipsoid is located at the center of the corresponding D-XPR, and the second focus of the ellipsoid is located at the center focus of the corresponding EUV lithography port. The surface of each multilayer film collection mirror is covered with a multilayer film that matches the target output wavelength (Mo / Si multilayer film is preferred for 13.5nm), and its normal reflectivity meets the in-band power requirements of the target port (preferably not less than 55% normal reflectivity to the target output wavelength, and more preferably not less than 60%). The solid angle of each multilayer film collection mirror meets the in-band power budget of the UTA, preferably not less than 1.5 sr, and more preferably not less than 2.0 sr.

[0095] By integrating an intermediate focus module at the light output port, the solution of this application not only greatly extends the service life of the back-end optical components, but also ensures that the extreme ultraviolet beam transmitted to the lithography scanner has extremely high purity, stability and controllability, providing a reliable light source guarantee for high-precision chip manufacturing.

[0096] In one embodiment of this application, no intermediate focal module is provided on each light output port of the optical device. Extreme ultraviolet radiation is directly coupled into the optical application port of the downstream device after being output from the multilayer film collecting mirror. For example, the multilayer film collecting mirror may not adopt an ellipsoidal-intermediate focal dual focal geometry, but may adopt a parabolic, hyperboloid, or freeform surface mirror type to collimate, shape, or directly focus the target output wavelength radiation of the corresponding D-XPR to the optical application port.

[0097] It is worth noting that the operation of the optical device without an intermediate focus module mainly relies on three physical safeguards: magnetic confinement of charged particles, buffer gas interception, and direct transmission with low light spread. Firstly, regarding charged particle protection, Sn in the D-XPR is constrained by both the tokamak's circumferential magnetic field and poloidal field, limiting its movement within the magnetic surface and preventing it from forming a straight flight path towards the multilayer film collecting mirror, thus fundamentally eliminating the threat of charged debris bombardment. Secondly, for neutral particle protection, injecting buffer gas with a partial pressure of 0.1 Pa to 5 Pa into the aperture of the multilayer film collecting mirror effectively intercepts neutral tin atoms and other neutral debris; because the buffer gas has an extremely low photon absorption cross section at 13.5 nm (91.85 eV) (σ ≈ 7 × 10⁻⁶), it effectively blocks neutral tin atoms and other neutral debris.-22 (cm²), and the integrated optical depth under 5Pa pressure and 1m path is only about 9×10 cm². -5 The corresponding EUV transmission loss is approximately 0.009%, a negligible loss that has been verified to not affect EUV yield in low numerical aperture lithography machines. Finally, thanks to the effective beam spread of D-XPR itself being controlled at ≤3.3 mm²·sr, the optical device does not require additional beam spread filtering using an intermediate focus module. Compared to optical devices containing an intermediate focus module, this intermediate focus module-free optical device successfully reduces one to three reflective surfaces in the transmission optical path from the multilayer film collection mirror to the mask. With a single reflective surface efficiency of 60% to 70%, this can improve the overall link efficiency by 1.7 to 4.6 times, significantly optimizing the transmission performance of EUV light.

[0098] For example, in an illumination optics system including an extreme ultraviolet radiation source assembly and an optical application port, a condenser lens assembly customized for the spatial distribution of the D-XPR volume light source can be used, thereby eliminating the need for an intermediate focal module and field and pupil blade mirror arrays. This condenser lens assembly fully utilizes the spatial luminescence uniformity of the D-XPR volume light source (approximately 5 × 20 × 5 mm³ in the poloidal × circumferential × radial direction of a single radiation point), directly mapping EUV radiation onto the pupil surface of the lithography scanner. This eliminates the need for cumbersome blade mirror beam splitting and reassembly steps, achieving mask surface illumination uniformity ≥95% and meeting the directional characteristics (σouter / σinner) and dose repeatability requirements of less than 0.5% for lithography imaging. In terms of optical path structure, the total number of EUV reflective surfaces in the entire link from D-XPR to the mask is controlled to within 9 (including 1 multilayer film collecting mirror, no more than 2 condenser mirrors and 6 projection optical mirror groups). Compared with the standard configuration (approximately 12 to 14 reflective surfaces) including the intermediate focal module and the blade mirror system, this successfully reduces the number of EUV reflective surfaces by 3 to 5, which significantly improves the EUV link efficiency by 2.5 to 5 times, thereby significantly increasing the EUV power at the mask. Alternatively, while maintaining the same mask power, the driving power can be reduced to 1 / 3 to 1 / 5 of the original, greatly reducing the overall operating cost of the extreme ultraviolet radiation source components. In addition, the dose control function originally undertaken by the intermediate focal shutter can be equivalently replaced by a rotating blade shutter installed at the exit of the multilayer film collecting mirror with a frequency of not less than 200Hz.

[0099] In one embodiment of this application, the extreme ultraviolet (EUV) radiation source assembly can also integrate a divertor subsystem. This divertor subsystem includes a specially designed target plate, whose core function is to receive and process the residual heat flux and waste particles escaping from the plasma edge. Serving as the "exhaust port" and "waste discharge channel" of the EUV radiation source assembly, the divertor subsystem can be guided by a magnetic field to precisely deflect and converge the particle stream carrying extremely high heat loads onto the target plate surface. This effectively prevents damage to the core optical components and vacuum cavity walls from extreme thermal shock, ensuring the thermal balance and safety of the entire EUV radiation source assembly under steady-state operation.

[0100] In one embodiment of this application, the extreme ultraviolet radiation source assembly can employ an XPTR configuration, in which the secondary X-point is precisely positioned on an open magnetic field line within the divertor channel, and discrete radiation points are formed near the secondary X-point. This unique magnetic configuration design, through the secondary X-point, physically separates the exhaust region that generates strong radiation from the constrained core plasma in space. This not only effectively avoids interference from radiation cooling on the core plasma performance but also significantly improves the stability and controllability of the heat dissipation process.

[0101] In practical applications, the extreme ultraviolet (EUV) radiation source component proposed in this application combines the sputtering main input mode of a cryogenic liquid metal divertor with a self-regulating closed loop of "vapor shielding as radiation output," achieving steady-state, extremely low net consumption (Sn quasi-closed-loop self-circulation) and single-source multi-machine light supply. The overall diameter is approximately 1.8 to 2.5 meters, with a total electrical power of 2MW to 10MW, capable of simultaneously supplying light to 4 to 17 scanners. By replacing the specified heavy metal seed and multilayer film coating, the EUV radiation source component can flexibly output in different wavelengths: including 13.5nm tin light for current EUV lithography nodes, 6.5nm to 6.7nm BEUV light (Gd / Tb seed) for next-generation lithography nodes, and various UTA ​​bands within the 2nm to 15nm range such as 4nm to 7nm soft X-rays (W seed).

[0102] It is worth noting that the extreme ultraviolet radiation source component proposed in this application embodiment has a great degree of design freedom in terms of geometric dimensions and current parameters, and can be freely scaled within a wide range according to the target output power and economy. For example, the outer diameter of the component is preferably 1 to 4 meters; the total power consumption is preferably 1 to 20 megawatts; during steady-state operation, the total radiation within the target unresolved transition array band output from the N output ports is preferably not less than 500 watts; the large radius R ∈ [0.3m, 2.0m], preferably R ∈ [0.5m, 1.0m]; the small radius a ∈ [0.1m, 0.6m], corresponding to an aspect ratio A = R / a ∈ [2, 5]; the plasma volume V ∈ [0.05m³, 10m³], preferably V ∈ [0.3m³, 2m³]; the plasma current I_p ∈ [50kA, 2MA], preferably I_p ∈ [150kA, 500kA]; the circumferential magnetic field B_T ∈ [1T, 10T], preferably B_T ∈ [2.5T, 4T] (applicable to NbTi) or [4T, 8T] (applicable to Nb3Sn or ReBCO). It should be emphasized that any extreme ultraviolet radiation source component that meets these geometric dimensions and current parameter ranges, regardless of the specific values ​​of the aforementioned geometric dimensions and current parameters, falls within the protection scope of this application.

[0103] In one embodiment of this application, the plasma operates in a radiation-dominated mode, meaning the volume-average radiative power fraction (f_rad) is significantly higher than the operating point of a conventional fusion tokamak, which is dominated by thermal conduction (the operating point of a conventional fusion tokamak is typically f_rad < 0.3). This allows most of the input power to be transported outward via radiation cooling of the high-Z impurity. Simultaneously, the electron temperature (Te) in the magnetic null region is controlled within a range that allows the high-Z impurity to be in the emission charge state of the target unresolved transition array, and the core electron temperature is lower than the level required for fusion reactor operation (preferably Te ≤ 5 keV; the specific upper limit is determined by the charge state requirements of the high-Z impurity and the radiation-dominated operating range, and this embodiment of the application does not limit this).

[0104] In one embodiment of this application, the plasma operates within a physical parameter range decoupled from plasma performance / fusion performance, functioning in a radiation-dominated mode. Specifically, this includes: a volume average power density P / V ≤ 8 MW / m³ (significantly lower than the typical P / V > 50 MW / m³ for fusion reactors), and a safety factor q. 95 ≥3. The Greenwald normalized density n_e / n_GW≤0.7, and the volume-average radiated power fraction f_rad is in the radiation-dominant range (preferably f_rad>0.5, more preferably f_rad≥0.7, the lower limit of which depends on the type of high-Z impurities, the injection rate, and the operating point; this application does not limit this). It should be emphasized that the setting of the above physical parameter range does not depend on the specific geometric dimensions of the extreme ultraviolet radiation source component or the absolute value of the plasma current.

[0105] Next, the parameters in the extreme ultraviolet radiation generation scheme proposed in this application will be illustrated using the following application scenarios with different wavelengths as examples.

[0106] The first application is 13.5nm extreme ultraviolet lithography (EUVL): Sn is selected as the heavy metal, and by maintaining the electron temperature in the magnetic zero-point region within the range of 30eV to 50eV, the Sn element is forced into a Sn-like state. 8+ To Sn 14+ The high-charge state region is used to excite extreme ultraviolet radiation with a target output wavelength of 13.5 nm ± 2% (corresponding to the UTA of the 4d→4f transition). In this example, the multilayer film coating of the multilayer film collection mirror is a molybdenum / silicon (Mo / Si) multilayer film, which is mainly used in extreme ultraviolet lithography processes at the 7nm, 5nm and 3nm nodes.

[0107] The second method, 6.7nm BEUV application: This involves specifying Gd or Tb, or a combination of both, as the heavy metal. By maintaining the electron temperature in the magnetic zero-point region within the range of 60eV to 120eV, the Gd or Tb elements are forced to remain in the Gd region. 9+ / Tb 9+ The high-charge state region of the divertor excites extreme ultraviolet radiation with a target output wavelength of 6.5 nm to 6.7 nm (corresponding to the 4d→4f transition UTA). In this example, the multilayer film coating of the multilayer film collection mirror is a high-reflectivity multilayer film such as lanthanum / boron carbide (La / B4C), lanthanum / boron (La / B), or lanthanum / molybdenum carbide (La / Mo2C), mainly used in extreme ultraviolet lithography processes at nodes of 2 nm and below. Meanwhile, the liquid metal pool of the divertor can be flexibly adjusted to a tin-gadolinium (Sn-Gd) or tin-terbium (Sn-Tb) eutectic alloy or injected using a gadolinium vapor nozzle to accommodate higher element melting points.

[0108] The third type, 4nm to 7nm soft X-ray application: W is selected as the heavy metal, and by maintaining the electron temperature in the magnetic zero-point region within the range of 200eV to 1500eV, the W element is forced to exist in a W-like state. 22+ / W 45+The high-charge state region excites a quasi-continuous spectral band of unresolved tungsten transition array in the target output wavelength range of 4 nm to 7 nm (covering the 5p→4d transition band from 4.5 nm to 5.5 nm and the 5d→4f transition band from 6 nm to 7 nm). In this example, the multilayer film coating of the multilayer film collecting mirror is a multilayer film coating with equivalent high reflectivity, such as molybdenum / yttrium (Mo / Y), chromium / scandium (Cr / Sc), or chromium / vanadium (Cr / V). It is mainly used in soft X-ray microscopy, actinic mask detection, ultra-high numerical aperture (NA) lithography exploration, and X-ray lithography. The divertor target plate can utilize an existing tungsten divertor plate, directly supplying tungsten to the plasma through a sputtering mechanism.

[0109] Fourth, extended applications of other UTA elements: When xenon (Xe) is selected as the specified heavy metal, the main charge state is Xe. 10+ The electron temperature in the magnetic null region is maintained between 25 eV and 40 eV, with a target output wavelength of 11.0 nm to 11.5 nm, coupled with a molybdenum / beryllium (Mo / Be) multilayer film; when molybdenum (Mo) is selected as the specified heavy metal, the dominant charge state is Mo. 20+ The electron temperature in the magnetic null region is maintained between 60 eV and 100 eV, with a target output wavelength of 9.5 nm to 10.5 nm, coupled with a molybdenum / yttrium (Mo / Y) multilayer film; when bismuth (Bi) is selected as the specified heavy metal, the dominant charge state is Bi. 15+ The electron temperature in the magnetic null region is maintained between 80 eV and 150 eV, with a target output wavelength of 8 nm to 10 nm, and is coupled with a lanthanum / boron carbide (La / B4C) multilayer film; when antimony (Sb) is selected as the specified heavy metal, the dominant charge state is Sb. 9+ The electron temperature in the magnetic zero region is maintained at 30eV to 50eV, and the target output wavelength is 13nm to 14nm, combined with a molybdenum / silicon (Mo / Si) multilayer film.

[0110] It is worth noting that during the life cycle of the extreme ultraviolet radiation source component, the extreme ultraviolet radiation source component has a flexible "one machine, multiple bands upgrade" capability. That is, without replacing the core main hardware such as magnets, vacuum chambers, current drivers or magnetic disturbance devices, only the following components need to be replaced to achieve flexible switching of the working band: vapor nozzle injection device or liquid metal pool in heavy metal injection device; multilayer film coating of multiple sets of multilayer film collection mirrors; and plasma operating parameters (such as electron temperature, incident rate of specified heavy metals, etc.).

[0111] See Figure 2 , Figure 2 The flowchart illustrates a method for generating extreme ultraviolet radiation according to an embodiment of this application, specifically including the following steps 202 to 208: Step 202: Generate plasma using a magnetic confinement device.

[0112] Step 204: When the plasma meets the preset injection conditions, control the heavy metal injection device to inject a specified heavy metal into the magnetic confinement device so that the specified heavy metal forms an unresolved transition array radiation in the magnetic zero point region.

[0113] Step 206: Control the magnetic perturbation device to shrink the unresolved transition array radiation into multiple discrete radiation points.

[0114] Step 208: When multiple discrete radiation points meet the radiation acquisition conditions, control the optical device to acquire extreme ultraviolet radiation based on multiple discrete radiation points.

[0115] It should be noted that when controlling the heavy metal injection device to inject a specified heavy metal into the magnetic confinement device, it is necessary to ensure that the specified heavy metal reaches a sufficient concentration in the X-point region, thereby efficiently generating UTA radiation of the desired target output wavelength. In actual operation, although the ratio of the ion concentration to the electron concentration (n_z / n_e) of the specified heavy metal usually falls within the range of 10-4 to 10-2, this range is not a rigid limitation of the embodiments of this application. The specific concentration value can be determined based on the type of specified heavy metal element used, the magnitude of the target radiation power, and the various physical parameters of the current plasma, as long as it can ultimately ensure that UTA radiation that meets the photolithography requirements is formed near the X-point region.

[0116] The solution of this application embodiment realizes directional and efficient collection of extreme ultraviolet radiation, thereby breaking through the physical limitations of traditional large-volume plasma light sources in terms of light spread, and achieving an extreme ultraviolet radiation generation effect with small light spread, high stability and easy precise collection.

[0117] In one embodiment of this application, the optical device includes multiple sets of multilayer film collecting mirrors and light output ports corresponding to the multilayer film collecting mirrors, with each multilayer film collecting mirror corresponding to a discrete radiation point. The aforementioned control optical device, which collects extreme ultraviolet radiation based on multiple discrete radiation points, may include the following steps: Multiple sets of multilayer film collecting mirrors are controlled to collect extreme ultraviolet radiation emitted from multiple discrete radiation points, and the extreme ultraviolet radiation is delivered to the corresponding light output port.

[0118] It should be noted that after the heavy metal injection device injects a specified heavy metal into the magnetic confinement device, forming an unresolved transition array radiation in the magnetic null region, a circumferential non-uniformity can be created on the X-point radiation band using a magnetic perturbation device. This shrinks the originally continuous annular X-point radiation band into N independent discrete radiation points. Subsequently, N sets of multilayer film collecting mirrors (whose reflection bands match the target output wavelength) can be used to collect the extreme ultraviolet radiation of the target output wavelength emitted from these N discrete radiation points, and each radiation point can be independently transmitted to its corresponding N output ports. This eliminates the limitation of LPP light sources relying on statistical pulse counts to control the dose. Instead, by using a high-speed shutter at the output port, combined with feedback control of the specified heavy metal incident rate, precise and flexible steady-state control of the output dose can be achieved.

[0119] The solution applied in this application not only greatly improves the collection efficiency of extreme ultraviolet radiation, but also ensures that there is no interference between the various radiation channels, providing a hardware foundation for the subsequent simultaneous application of multiple beams of light or independent dose control.

[0120] In one embodiment of this application, after the above-mentioned control optical device collects extreme ultraviolet radiation based on multiple discrete radiation points, it may further include the following steps: Based on the radiation parameters of extreme ultraviolet radiation, at least one of the following is adjusted: the electromagnetic wave frequency of the plasma, the incident rate of a specified heavy metal, the excitation intensity of the magnetic disturbance device, and the shutter speed of the light-emitting port in the optical device.

[0121] It should be noted that radiation parameters refer to specific physical quantities characterizing the quality of an extreme ultraviolet (EUV) radiation beam. These typically include data such as the EUV radiation power (intensity), center wavelength, spectral bandwidth, and spatial distribution of the beam. Radiation parameters can serve as a reference for feedback adjustment, used to determine whether the current output EUV radiation meets preset process or experimental requirements.

[0122] The electromagnetic frequency of plasma refers to the oscillation frequency of the radio frequency or microwave source used to excite or maintain the plasma state. It determines the efficiency of energy coupling into the plasma. By adjusting the electromagnetic frequency, the core electron temperature of the plasma can be controlled, thereby affecting the conversion efficiency and generation intensity of extreme ultraviolet radiation.

[0123] The incident rate of a specified heavy metal refers to the number / flux of a specified heavy metal atom or ion injected into the magnetic confinement device per unit time. The incident rate determines the number density of particles participating in the transition radiation, thereby controlling the intensity (dose) of the radiation source and the purity of the spectrum, preventing self-absorption effects due to excessive particle density. For example, the incident rate of tin can maintain a proportional relationship with the LHCD power: n_Sn·P_LHCD≈constant, which can be selected based on the required 13.5nm output power.

[0124] The excitation intensity of a magnetic disturbance device refers to the magnitude or amplitude of the energy of the external magnetic disturbance field applied to the plasma. Changes in the excitation intensity affect the magnetic field configuration in the magnetic null region. By adjusting the excitation intensity, the electron temperature, spatial position drift, or morphological divergence of discrete radiation points can be corrected, ensuring that the discrete radiation points meet the radiation acquisition conditions.

[0125] In optical devices, the shutter at the light output port refers to a mechanical or photoelectric switch installed at the end of the beam transmission path or at a critical node. The shutter controls whether extreme ultraviolet (EUV) radiation can be output to downstream equipment through the light output port, enabling on / off control of EUV radiation output, pulse shaping, or instantaneous cut-off of the beam to protect downstream equipment when radiation parameters are unstable.

[0126] In practical applications, there are various ways to adjust at least one of the following based on the radiation parameters of extreme ultraviolet radiation: the electromagnetic wave frequency of the plasma, the incident rate of a specified heavy metal, the excitation intensity of the magnetic disturbance device, and the shutter speed of the light output port in the optical device. The specific method chosen depends on the actual situation, and this application does not impose any limitations on this approach. In one possible implementation, when a decrease in the power of extreme ultraviolet radiation is detected, it indicates a change in the electron density of the plasma, causing the original driving frequency to no longer match. At this time, the frequency of the electromagnetic wave applied to the plasma (such as the frequency of the radio frequency source) can be scanned and fine-tuned to resonate with the current plasma frequency, thereby increasing energy absorption and allowing the radiation intensity to quickly return to the set value. In another possible implementation, the cumulative dose or instantaneous intensity of the extreme ultraviolet radiation can be calculated. If the radiation parameters deviate from the target value (such as a decrease in light intensity), the incident rate of the specified heavy metal or the ejection frequency is increased; conversely, the incident rate is decreased, thereby maintaining the long-term stability of the output beam by adjusting the supply of the specified heavy metal.

[0127] For example, a shutter with a frequency response of at least 200Hz can be used for millisecond-level rapid on / off adjustment, serving as the first line of defense for dose control of the extreme ultraviolet radiation source component; combined with LHCD power modulation in the 1Hz to 50Hz frequency band, medium-speed dynamic fine-tuning of plasma radiation intensity can be achieved; and combined with specified heavy metal incident rate control not exceeding 1Hz, long-term steady-state substrate calibration can be completed from the fuel supply source. This three-level linkage feedback architecture achieves extremely high dose control accuracy of less than 0.5% for the steady-state light source.

[0128] By applying the scheme of this application embodiment, the "source end" (electromagnetic wave frequency, incident rate) can be dynamically and collaboratively adjusted according to the actual output of extreme ultraviolet radiation to stabilize light intensity and spectral quality, and the shutter speed of the output port can be controlled to ensure the timing and safety of the output beam. This multi-level linkage adjustment mechanism greatly improves the long-term stability of extreme ultraviolet radiation, the accuracy of dose control, and operational safety, ensuring that every beam of light output precisely meets the application requirements.

[0129] In one embodiment of this application, before the above-mentioned heavy metal injection device injects a specified heavy metal into the magnetic confinement device, the following steps may be included: Obtain the target output wavelength of extreme ultraviolet radiation; The specified heavy metal is determined based on the target output wavelength.

[0130] It should be noted that the target output wavelength refers to the specific band value of extreme ultraviolet radiation required for the actual operation of downstream equipment (such as lithography machines or testing instruments).

[0131] For example, assuming the target output wavelength is in the range of 2nm to 15nm, high-Z impurities such as tin, gadolinium, terbium, tungsten, molybdenum, xenon, and bismuth can be precisely injected into the plasma. Utilizing the specific transitions of these high-Z impurities in their highly ionized states within a specific temperature range at point X (mainly UTA transitions of n=4→n=4 or n=5→n=4), the originally dispersed energy is highly concentrated, allowing 5% to 15% of the total radiated power to precisely fall on the target output wavelength. Simultaneously, the core electron temperature that the plasma needs to reach to produce very strong UTA radiation near point X can be calculated, thus providing a clear physical parameter benchmark for subsequent plasma manipulation.

[0132] The solution of this application embodiment first determines the target output wavelength and then reverses to deduce the specified heavy metal, avoiding invalid radiation or spectral pollution caused by blind injection, and ensuring that the injected specified heavy metal atoms can be efficiently converted into radiation of the target output wavelength in the magnetic zero point region, which greatly improves the targeting and overall efficiency of the extreme ultraviolet radiation source component.

[0133] In one embodiment of this application, before the above-mentioned control optical device collects extreme ultraviolet radiation based on multiple discrete radiation points, the following steps may be included: The core electron temperature and the electron temperatures of multiple discrete radiation points of the plasma are obtained, wherein the core electron temperature is matched with a specified heavy metal; When the electron temperature matches the core electron temperature, multiple discrete radiation points are determined to meet the radiation acquisition conditions.

[0134] It should be noted that the core electron temperature refers to the ideal temperature that the central region of the plasma needs to reach in order to excite a specified heavy metal to produce UTA radiation. UTA radiation can only occur when the specified heavy metal is at the core electron temperature. The core electron temperature can be determined according to the charge state requirements of the specified heavy metal corresponding to the target output wavelength. For example, for tin, the core electron temperature can be set to no more than 3 keV to match the luminescence conditions of 13.5 nm; for tungsten, the core electron temperature can be set to no more than 5 keV to match the luminescence conditions of 4 nm to 7 nm.

[0135] The electron temperature of multiple discrete radiation points refers to the actual electron temperature of each independent radiation point spatially separated after being contracted by the magnetic perturbation device. This electron temperature can reflect the true operating state of each discrete radiation point.

[0136] By comparing the electron temperature of each discrete radiation point with the ideal core electron temperature, invalid radiation points that have low luminous efficiency and impure spectrum due to substandard temperature can be intelligently eliminated, thereby improving the spectral purity and energy conversion efficiency of the final output extreme ultraviolet radiation. It also effectively avoids unnecessary heat load or pollution to downstream equipment caused by stray light of non-target output wavelength.

[0137] In one embodiment of this application, after the above-mentioned control magnetic perturbation device shrinks the unresolved transition array radiation into multiple discrete radiation points, it may further include the following steps: If multiple discrete radiation points do not meet the radiation acquisition conditions, at least one of the following is adjusted: the incident rate of a specified heavy metal, the electromagnetic wave frequency of the plasma, and the excitation intensity of the magnetic disturbance device, until multiple discrete radiation points meet the radiation acquisition conditions.

[0138] For example, taking the radiation acquisition conditions as matching the electron temperature of discrete radiation points with the core electron temperature (e.g., the deviation of the electron temperature is within ±30% of the core electron temperature), by adjusting at least one of the incident rate of a specified heavy metal, the electromagnetic wave frequency of the plasma, and the excitation intensity of the magnetic disturbance device, the electron temperature of each discrete radiation point can be locked within the temperature window of the UTA radiation charge state, ensuring that the radiation intensity of extreme ultraviolet radiation remains highly stable, thereby outputting continuous and pure extreme ultraviolet radiation.

[0139] By applying the solution of this application embodiment, the above-mentioned dynamic correction mechanism not only reduces the invalid radiation time, but also ensures that the final output extreme ultraviolet radiation maintains a high degree of consistency in intensity, spectral purity and pointing accuracy, which greatly improves the reliability and practicality of the extreme ultraviolet radiation source component.

[0140] See Figure 3 , Figure 3 This figure shows a top view of an extreme ultraviolet (EUV) radiation source assembly according to an embodiment of this application. The figure not only shows the central solenoid, vacuum chamber, multi-handled circumferential field coils (16 handles in this case, which are only schematic and do not constitute a limitation of this application) surrounding the vacuum chamber, four ellipsoidal Mo / Si multilayer film collecting mirrors (located on the inner back side of the XPR, with the concave surface facing the corresponding D-XPR discrete radiation point, the first focal point located at the center of the corresponding XPR, and the second focal point located at the light-emitting port), four light-emitting ports for connection to the photolithography scanner, radial current bars (closely attached to both sides of the XPR, establishing local magnetic perturbation at the XPR to obtain a local X point), and four tin vapor nozzles (uniformly distributed along the circumferential direction), but also shows four discrete radiation points (each radiation point ≤10mm) located near the magnetic null point outside the plasma ring (tokamak magnetic confinement).

[0141] See Figure 4 , Figure 4A poloidal cross-sectional view of an extreme ultraviolet (EUV) radiation source assembly according to another embodiment of this application is shown, with the large radius R (m) as the horizontal axis and the height Z (m) as the vertical axis. The design parameters of the EUV radiation source assembly are a plasma current of 1 mA, a large radius of 1.2 m, a small radius of 0.6 m, an elongation ratio of 1.0, and a layout combining an outer equatorial plane single X-point configuration with an EUV emission port (400 mm aperture). The plasma boundary is defined by the outermost closed magnetic surface and is enclosed by the vacuum chamber wall (located between the plasma and the toroidal field coils). To control and confine the plasma, the EUV radiation source assembly is configured with a magnet system (including toroidal field coils and poloidal field coils). The poloidal field coils include an inner poloidal field coil (PF inner), a first vertical field coil (PF vf1, Poloidal Field vertical field 1), a second vertical field coil (PF vf2, Poloidal Field vertical field 2), and a divertor poloidal field coil (DivertorPF). The inner poloidal field coil is typically located at or near the central column, driving the plasma current through electromagnetic induction and participating in balance control. The first and second vertical field coils generate vertical magnetic field components to balance the circumferential expansion force of the plasma, preventing outward drift and controlling its radial position. The divertor poloidal field coil, located near the divertor region, shapes the X-point configuration. By adjusting the current in the divertor poloidal field coil, the position of the X-point, the shape of the divertor legs, and the distribution of heat flux on the target plate can be controlled. Since the X-point is precisely where D-XPR radiation occurs, the current configuration of the divertor poloidal field coil affects whether the radiation region is aligned with the geometric focus of the EUV multilayer collecting mirror. The poloidal field coil generates a poloidal magnetic field, which, combined with the circumferential magnetic field generated by the circumferential field coil, shapes the magnetic configuration of the plasma. The output pipe at the light outlet is fitted with a metal sealing flange; discrete radiation points are located near the plasma X-point for generating extreme ultraviolet radiation or related experiments.

[0142] See Figure 5 , Figure 5 This illustration shows a schematic diagram of the formation principle of a discrete XPR according to another embodiment of this application, which transforms continuous UTA ​​radiation into discrete radiation points through a circumferential symmetry breaking mechanism. Figure 5 Figure (a) shows the state without circumferential perturbation, where a continuous XPR ring with a circumference of approximately 377 cm is formed. The light spread is too large, which means that a single collecting mirror cannot collect all the light and violates the light spread limit of the scanner. Figure 5Figure (b) shows the state after adding eight radial current bars (two bars in each pair symmetrically arranged on both sides of a D-XPR position, a total of four pairs, each bar about 12 kA). These radial current bars break the circumferential symmetry and shrink the radiation to four discrete D-XPR points, each point being about 5 mm in size. Figure 5 Figure (c) shows the circumferential distribution of radial magnetic perturbation δB_r(φ) and radiation intensity I(φ). It shows that the radiation intensity reaches its peak at the four D-XPR locations (i.e., circumferential angles of 0°, 90°, 180°, and 270°, respectively), with a normalized amplitude of 1.0. The radiation intensity at other locations decreases significantly, and the radiation concentration is increased by about 190 times, thus achieving efficient and directional extreme ultraviolet radiation output.

[0143] See Figure 6 , Figure 6 The diagram illustrates the architecture of an optical system 600 provided in one embodiment of this application. The optical system 600 includes an extreme ultraviolet radiation source component 100.

[0144] It should be noted that an optical system refers to a complete set of sophisticated hardware used to generate, transmit, focus, shape, or detect optical signals.

[0145] By integrating the extreme ultraviolet radiation source component as the core into the optical system, the solution of this application achieves integrated packaging from energy input to light output. This design not only greatly shortens the optical path transmission distance and reduces photon loss during transmission, but also facilitates closed-loop control of the light source (such as temperature regulation), thereby ensuring that the final output extreme ultraviolet radiation has industrial-grade high power density and extremely high stability.

[0146] In one embodiment of this application, the optical system further includes a plurality of optical application ports arranged around the extreme ultraviolet radiation source component, and the optical application ports are connected to at least one of an extreme ultraviolet lithography scanner, an beyond extreme ultraviolet lithography scanner, a photochemical mask inspection system, a soft X-ray microscope, and an X-ray inspection system.

[0147] It should be noted that the optical application port refers to the physical interface or optical path exit designed in the optical system, which is used to guide extreme ultraviolet radiation to downstream equipment (such as photolithography scanners, inspection equipment, etc.), and can also be called the application station.

[0148] Extreme ultraviolet (EUV) lithography scanners are manufacturing equipment that uses extreme ultraviolet light to transfer patterns on semiconductor chips.

[0149] Beyond extreme ultraviolet lithography scanners refer to next-generation lithography equipment with wavelengths shorter than traditional extreme ultraviolet light.

[0150] A photolithography mask inspection system is a specialized device that uses light of the same wavelength as that used in photolithography (i.e., "photolithography" light) to inspect defects in photolithography masks.

[0151] A soft X-ray microscope is a scientific instrument that uses soft X-ray wavelengths for high-resolution imaging.

[0152] An X-ray inspection system is a device that uses the penetrating power of X-rays to perform non-destructive testing or component analysis on the internal structure of an object.

[0153] For example, an extreme ultraviolet (EUV) radiation source component can be used as the central light source, with K (2≤K≤N) downstream devices, each with its own optical application port, arranged around it. Through a sophisticated optical transmission system, the EUV radiation generated by the central light source can be efficiently distributed to each of the surrounding optical application ports. The exposure dose control of each optical application port can be independent and non-interfering, and the wavelength power received by each optical application port can be precisely matched to its specific requirements (e.g., in mass production lithography, the wavelength power of the optical application port is preferably above 50 watts). This allows for efficient collaboration throughout the entire process from manufacturing to inspection within a unified architecture.

[0154] By applying the solution of this application embodiment, a "light source sharing ecosystem" is successfully constructed by arranging multiple optical application ports around the optical system and connecting to diverse downstream devices. This not only significantly reduces the construction and operation and maintenance costs of expensive extreme ultraviolet light sources, but also achieves the ultimate utilization of resources. That is, the same beam of light can be used for photolithography, as well as for quality control (mask inspection, X-ray inspection) and basic scientific research (microscopy). This modular and multifunctional design greatly improves the overall economic efficiency and scientific research output capability of the optical system.

[0155] In one embodiment of this application, the optical performance of each optical application port can be controlled. For example, the effective light yield of the 13.5nm lithography optical application port is ensured not to exceed 3.3mm²·sr, and other bands such as BEUV or soft X-rays also strictly adhere to the upper limit of their respective process yields to guarantee imaging quality. Secondly, to maximize cost reduction and efficiency, each optical application port can share the magnet cooling, LHCD power supply, and vacuum system of the central light source. Thanks to the co-source multi-wavelength mechanism, the optical system allows the delivery of extreme ultraviolet radiation of different bands to different optical application ports at the same time, such as performing lithography and detection simultaneously without conflict, achieving multi-task parallel processing.

[0156] The extreme ultraviolet (EUV) radiation source assembly described in this application can transform a steady-state superconducting tokamak, originally used for nuclear fusion research, into an EUV and soft X-ray source serving semiconductor manufacturing and precision metrology. The advantages of the EUV radiation source assembly lie in its high economic efficiency and flexibility: compared to the huge investment required for free-electron lasers or steady-state micro-beaming solutions, the EUV radiation source assembly has a compact device size (approximately 1.8 meters), significantly reduced investment (in the tens of millions of US dollars), and its core physical mechanisms (such as XPR and liquid tin divertors) have been independently experimentally verified on mainstream international fusion devices. This allows the duty cycle of the LPP (Liquid Proton) source to be increased from the original 0.15% to a steady-state operating level approaching 100%. This means that, at the same power output, the stringent requirements for internal instantaneous plasma density are reduced by approximately 600 times, greatly alleviating engineering difficulties. Simultaneously, the overall conversion efficiency of the EUV radiation source assembly has also achieved a qualitative leap, with the overall wall efficiency increasing from the traditional level to 0.05% to 0.16%, approximately four times that of the LPP source. Based on this, the extreme ultraviolet radiation source module has solved specific engineering problems by introducing key mechanisms such as discrete radiation points, multi-port extraction and self-adjusting closed loop, enabling the extreme ultraviolet radiation source module to provide a high-quality light source with steady-state, tunable wavelength (2nm to 15nm) at extremely low cost.

[0157] In practical applications, extreme ultraviolet (EUV) radiation source components can not only cover the current mainstream 13.5nm semiconductor EUV lithography (suitable for 7nm to 2nm logic and dynamic random access memory manufacturing), replacing or supplementing traditional LPP light sources; they can also proactively plan for next-generation technologies, providing prototype light sources for BEUV lithography (6.5nm to 6.7nm) at the ≤2nm node and soft X-ray lithography (4nm to 7nm) in the post-BEUV era. Furthermore, EUV radiation source components can simultaneously serve ultra-high numerical aperture lithography exploration, detection of various generations of photochemical masks, testing of multilayer optical components such as Mo / Si, La / B4C, and Mo / Y, biological microscopic imaging in the water window band (2.3nm to 4.4nm), and even calibration of astronomical instruments (such as solar EUV telescopes) and fundamental atomic physics research (such as UTA ​​spectroscopy, optical thickness effects, radiation-convection coupling, etc.). Ultimately, through a homogeneous multi-wavelength architecture, EUV radiation source components can achieve "factory-grade multi-wavelength one-stop light supply." This means that a single extreme ultraviolet (EUV) radiation source assembly can simultaneously deliver energy to multiple process nodes, including EUV lithography, BEUV scanning, and SXR inspection. This multi-machine shared architecture not only significantly reduces the enormous capital expenditure on light sources in advanced process wafer fabs, but also provides a highly cost-effective and innovative universal light source platform for semiconductor manufacturing and precision scientific exploration through a highly integrated physical design.

[0158] It is worth noting that the specific parameters involved in the embodiments of this application (including the large and small radii of the components, plasma volume, plasma current, circumferential magnetic field strength, LHCD power, incident rate, radiation power, electrical power, component outer diameter, solid angle of the collecting mirror, and number of light-emitting ports, etc.) are only example values ​​of preferred embodiments and can be arbitrarily scaled and adjusted without deviating from the physical architecture of this application. The physical architecture elements of this application include: configuring the magnetically confined plasma in the low-performance, radiation-dominant region of "anti-fusion optimization"; using high Z impurities to form UTA radiation near the X point; shrinking the continuous XPR into a discrete N-point radiation array by breaking circumferential symmetry; achieving steady-state impurity incident through the sputtering-dominant supply of the cryogenic liquid metal pool and the collaborative division of labor of multi-nozzle vapor injection; achieving multi-purpose functionality through homogeneous multi-port optical extraction; and achieving switchable output of different wavelengths (13.5nm, 6.7nm, 4nm to 7nm, etc.) by changing seed elements and multilayer film coatings. All of the above parameters can be freely scaled based on actual engineering factors such as target output power, selected high-Z impurities, selection of superconducting materials, cooling capacity, and lithography line production capacity requirements, within the framework of the physical architecture of this application.

[0159] In the first example of this application, regarding the geometry of the extreme ultraviolet radiation source component, the large radius R is 0.60m, the small radius a is 0.17m, the aspect ratio A is 3.5, the elongation ratio is 1.6, the triangular deformation δ is 0.3, the plasma volume V is approximately 0.56m³, and the outer diameter of the component is approximately 1.8m. The magnet uses an NbTi coil, with an operating temperature of 4.2K, a circumferential magnetic field B_T of 3.0T, a critical margin of 3.5 times, a total wire length of approximately 4.3km, and a material cost of approximately 13,000 yuan. The plasma parameters are set as follows: plasma current I_p is 294kA, and the safety factor q... 95 The value is 4.0, and the core electron density n_e is 0.8 × 10⁻⁶. 20 m -3 (Greenwald fraction 25%), core electron temperature approximately 1.5 keV, operating in L-mode or I-mode, without ELM. The LHCD uses a frequency of 2.45 GHz, with a parallel refractive index controlled at 1.98, an injection power of 3 MW, and an absorption power of 1.5 MW, achieving 100% non-inductive steady-state current drive. The total electrical power of the extreme ultraviolet radiation source assembly (including the quer tube and losses) is approximately 7.1 MW. The Sn supply subsystem includes eight Sn vapor nozzles evenly distributed circumferentially (one on each side of each D-XPR position), equipped with a small electron beam heated crucible (operating temperature approximately 1600 K); the divertor region has a liquid Sn pool (CPS capillary structure, pool depth 3 mm, operating temperature 700 ± 100 K), the main Sn incident mechanism is physical sputtering plus self-sputtering avalanche, and the Sn vapor background pressure is less than 10. -2Pa. The circumferential symmetry breaking device consists of eight radial current bars (two bars symmetrically arranged on either side of each D-XPR position), with a single bar current of approximately 12.5 kA, generating a radial magnetic perturbation δB_r of approximately 12.5 mT, and a total power consumption of less than 1 kW. This forms N=4 X-point radiators (D-XPR), each with dimensions of approximately 5 × 20 × 5 mm³, an electron temperature of approximately 40 eV, and a power of approximately 19 kW in the 13.5 nm band within the 4π zone at each point. EUV optical extraction uses four sets of ellipsoidal Mo / Si multilayer film collecting mirrors, each with a solid angle of approximately 2.5 sr and a reflectivity of 67% (corresponding to 13.5 nm EUV light), and a power of approximately 170 W in the 13.5 nm band at the IF exit of each port. The assembly is configured with four lithography scanners arranged radially around the device, each corresponding to a lithography port, and each port is equipped with an independent IF module, differential pumping, hydrogen buffer, and magnetic deflection. The total power of the module is approximately 7.3MW, and the overall efficiency is approximately 0.09% (total power of 4 ports: 680W / 7.3MW).

[0160] In the second example of this application, an economical configuration suitable for the R&D verification stage is described: only two D-XPR positions and two lithography machines can be set up, using conventional copper magnets in conjunction with pulse operation (approximately 10-second pulses), thereby further reducing component costs. This pulse scheme is a transitional solution for the technology verification stage, while the superconducting steady-state scheme is the preferred implementation method of this application. This pulse scheme does not represent an essential feature of this application.

[0161] In the third example of this application, a high-volume configuration is described: eight D-XPR positions can be set up to share with eight lithography scanners, the large radius R of the device is expanded to 0.9m, the circumferential magnetic field B_T is increased to 4T (using Nb3Sn or ReBCO), and the power per port at 13.5nm can reach more than 300W.

[0162] In the fourth example of this application, a second X point (XPTR configuration) can be arranged within the divertor channel, with the D-XPR located on an open magnetic field line near the second X point. This configuration isolates the radiation region from the core, further reducing the risk of Sn contamination.

[0163] In the fifth example of this application, a preferred Sn supply method is described, which combines liquid tin sputtering with nozzle assistance: the liquid Sn pool operates at a temperature of 700K and does not rely on evaporation. During the start-up phase, Sn vapor is injected through eight circumferential vapor nozzles (single-point flow rate approximately 10). 19 Sn / s) to establish the initial XPR; after steady state, the main Sn source is switched to liquid pool sputtering, and the nozzle flow rate is reduced to 0 to 10¹. 9Sn / s is used for fine adjustment. When the radiation at a certain D-XPR point deviates from the set value, only the nozzle corresponding to that D-XPR is adjusted without disturbing the liquid pool operating point. In addition, this design has single-failure tolerance capability; if any nozzle or liquid pool fails, the remaining path can maintain 100% power supply.

[0164] In the sixth example of this application, a next-generation lithography application is described: the main hardware of the extreme ultraviolet radiation source component is the same as in the first example (i.e., R=0.60m, B=3.0T, N=4), but the high-Z impurity element is replaced with Gd. The liquid metal pool is changed to a Sn-Gd eutectic alloy (liquidity line approximately 600K to 800K, retaining the advantage of low-temperature operation), with Gd passively supplied by the liquid pool; Gd vapor is injected through the nozzle (electron beam heating crucible, evaporating Gd at approximately 1900K). The plasma configuration is adjusted so that the core electron temperature is increased to approximately 80eV to 100eV near point X (achieved by slightly increasing the LHCD power and reducing the Sn incident amount). The multilayer films of the four ellipsoidal collecting mirrors are replaced with La / B4C (with a peak reflectivity of approximately 50% under 6.7nm illumination), while the rest of the optics remain unchanged. The output is approximately 80W per 6.7nm band at each output port, suitable for photochemical detection of BEUV lithography and photomask blanks at ≤2nm nodes.

[0165] In the seventh example of this application, the application of soft X-rays is described: the main hardware of the component is the same as in the first example, the divertor target plate uses a W plate (consistent with EAST and the International Thermonuclear Experimental Reactor), W is directly supplied to the plasma via a sputtering mechanism (no separate metal pool is required), Sn impurities are retained as X-point radiation enhancement (secondary source), and the primary radiating element is W. The plasma configuration is adjusted as follows: the core electron temperature is 800 eV to 1500 eV near the X-point, and the low-temperature region of 200 eV to 400 eV near the W divertor plate forms W. 22+ To W 37+ UTA. The multilayer films of the four ellipsoidal collecting mirrors were replaced with Mo / Y (peak reflectivity of approximately 25% to 30% under 5nm illumination) or Cr / Sc (peak reflectivity of approximately 30% to 40% under 4.5nm illumination). The output is approximately 30W per output port within the 4nm to 7nm band, suitable for soft X-ray microscopy (water window imaging), actinic detection, X-ray lithography exploration, and ultra-high nanometer lithography exploration.

[0166] In the eighth example of this application, a factory-level one-stop light supply solution is described: the main hardware of the components is the same as in the first example (N=4), but differential pumping and circumferential flow field separation are used to avoid excessive mixing of different elements in the plasma, achieving simultaneous multi-band output: D-XPR-1 and D-XPR-2 use Sn seeds, outputting 13.5nm, supplying two EUVL scanners; D-XPR-3 uses Gd seeds (local nozzle injection), outputting 6.7nm, supplying one BEUV scanner; D-XPR-4 uses W seeds (local sputtering on a W divertor plate), outputting 5nm, supplying one soft X-ray mask inspection system. The four collection mirrors are respectively configured with Mo / Si, Mo / Si, La / B4C, and Mo / Y coatings. This configuration can significantly save the cost of three independent light source systems.

[0167] In the ninth example of this application, an equivalent HTS scheme with the same physical architecture as the first example is described: the magnet uses ReBCO high-temperature superconducting tape, with an operating temperature of 20K to 40K (cooled by a regenerative cryogenic refrigerator or cryogenic circulating helium), the circumferential magnetic field B_T is increased to 5T (or can be reduced to 3T for a longer lifespan), and the large radius R can be appropriately reduced (e.g., R=0.45m) to maintain the same q. 95 Compared to the P / V HTS scheme, the advantages are liquid helium-free operation, simplified system and reduced maintenance costs, and magnets less prone to quenching.

[0168] In the tenth example of this application, a hybrid magnet is described: the circumferential field coil uses LTS (NbTi) to take advantage of its low cost and mature technology, and the central solenoid or local high field region uses HTS (ReBCO) inserts to locally enhance the magnetic field or reduce the coil size, which is suitable for scenarios where a balance is desired between the price advantage of LTS and the high field capability of HTS.

[0169] In the eleventh example of this application, a system without an intermediate focus module and without bladed mirrors is described: the main hardware of the components is the same as in the first example (R=0.60m, B=3.0T, N=4, Sn seed), only the optical extraction and illumination subsystem is changed. In terms of optical configuration, the multilayer film collecting mirror adopts 4 sets of parabolic Mo / Si multilayer film collecting mirrors (replacing the ellipsoid), each mirror is focused on the corresponding D-XPR, and the output end collimates the D-XPR radiation into a near-parallel beam; there is no intermediate focus module at the outlet of each collecting mirror, charged debris is confined by the tokamak magnetic field, and neutral Sn atoms are intercepted by the hydrogen purification airflow in the collecting mirror chamber; the shutter (rotating blade, ≥200Hz) is installed at about 0.5m at the outlet of the collecting mirror, replacing the dose control function of the shutter at the original intermediate focus. The illumination subsystem omits the field vane mirror and pupil vane mirror, and each port is equipped with a two-stage reflective condenser mirror (a combination of ellipsoidal and toroidal surfaces or a fully freeform surface), optimized for the 5×20mm D-XPR volume light source size, directly forming uniform illumination (uniformity ≥95%) on the scanner mask surface. Compared to the standard configuration (including the intermediate focus module and vane mirror system, totaling 10 reflective surfaces, with an estimated link efficiency of approximately 1.8% and a net power at the mask of approximately 6.9W), this embodiment (without the intermediate focus module, omitting the vane mirror, totaling 9 reflective surfaces) improves the estimated link efficiency to approximately 2.7% and the net power at the mask to approximately 10.3W by reducing the number of intermediate focus reflective surfaces and vane mirrors by one. This embodiment, together with the matching "no intermediate focus / omitted vane mirror" scanner illumination subsystem, represents a new source-machine interface architecture for next-generation lithography machine design, enabling joint development of customized illumination systems with lithography machine manufacturers; while the first example retains compatibility with existing scanners, and the two interfaces can coexist in parallel depending on market conditions.

[0170] The above is a schematic representation of an optical system according to this embodiment. It should be noted that the technical solution of this optical system belongs to the same concept as the technical solution of the extreme ultraviolet radiation source component described above. For details not described in detail in the technical solution of the optical system, please refer to the description of the technical solution of the extreme ultraviolet radiation source component described above.

[0171] In one embodiment of this application, the optical system may further include a control unit, which may be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or personal computers (PCs). The control unit may also be a mobile or stationary server.

[0172] The control unit is used to execute computer-executable instructions, which, when executed by the control unit, implement the steps of the above-described extreme ultraviolet radiation generation method.

[0173] The above is a schematic representation of a control unit in this embodiment. It should be noted that the technical solution of this control unit belongs to the same concept as the technical solution of the extreme ultraviolet radiation generation method described above. Details not described in detail in the technical solution of the control unit can be found in the description of the technical solution of the extreme ultraviolet radiation generation method described above.

[0174] An embodiment of this application also provides a computer-readable storage medium storing computer-executable instructions that, when executed by a processor, implement the steps of the above-described extreme ultraviolet radiation generation method.

[0175] The above is an illustrative scheme of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium belongs to the same concept as the technical solution of the extreme ultraviolet radiation generation method described above. For details not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the extreme ultraviolet radiation generation method described above.

[0176] An embodiment of this application also provides a computer program, wherein when the computer program is executed in a computer, it causes the computer to perform the steps of the above-described extreme ultraviolet radiation generation method.

[0177] The above is an illustrative scheme of a computer program according to this embodiment. It should be noted that the technical solution of this computer program and the technical solution of the extreme ultraviolet radiation generation method described above belong to the same concept. For details not described in detail in the technical solution of the computer program, please refer to the description of the technical solution of the extreme ultraviolet radiation generation method described above.

[0178] The foregoing has described specific embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired results. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0179] Computer instructions include computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. Computer-readable media can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in computer-readable media can be appropriately added or removed according to the requirements of patent practice. For example, in some regions, according to patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0180] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in this application are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments of this application.

[0181] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0182] The preferred embodiments disclosed above are merely illustrative of this application. This application does not exhaustively describe all details, nor does it limit the invention to the specific embodiments described. Clearly, many modifications and variations can be made based on the content of the embodiments of this application. These embodiments are selected and specifically described in this application to better explain the principles and practical applications of the embodiments of this application, thereby enabling those skilled in the art to better understand and utilize this application. This application is limited only by the claims and their full scope and equivalents.

Claims

1. A method for generating extreme ultraviolet radiation, comprising: Using a magnetic confinement device to generate plasma; When the plasma meets the preset injection conditions, the heavy metal injection device is controlled to inject a specified heavy metal into the magnetic confinement device so that the specified heavy metal forms an unresolved transition array radiation in the magnetic zero point region. The control magnetic disturbance device shrinks the unresolved transition array radiation into multiple discrete radiation points; When the multiple discrete radiation points meet the radiation acquisition conditions, the optical device is controlled to acquire extreme ultraviolet radiation based on the multiple discrete radiation points.

2. The method according to claim 1, wherein, The optical device includes multiple sets of multilayer film collecting mirrors and light output ports corresponding to the multilayer film collecting mirrors, with each multilayer film collecting mirror corresponding to a discrete radiation point. The control optics device collects extreme ultraviolet radiation based on the plurality of discrete radiation points, including: The system controls the multiple sets of multilayer film collecting mirrors to collect the extreme ultraviolet radiation emitted by the multiple discrete radiation points, and then transmits the extreme ultraviolet radiation to the corresponding light output port.

3. The method according to claim 1 or 2, wherein, After the control optics device collects extreme ultraviolet radiation based on the multiple discrete radiation points, it also includes: Based on the radiation parameters of the extreme ultraviolet radiation, at least one of the following is adjusted: the electromagnetic wave frequency of the plasma, the incident rate of the specified heavy metal, the excitation intensity of the magnetic disturbance device, and the shutter speed of the light output port in the optical device.

4. The method according to claim 1 or 2, wherein, Before the controlled heavy metal injection device injects a specified heavy metal into the magnetic confinement device, it further includes: Obtain the target output wavelength of the extreme ultraviolet radiation; The specified heavy metal is determined based on the target output wavelength.

5. The method according to claim 1 or 2, wherein, Before the control optics device collects extreme ultraviolet radiation based on the plurality of discrete radiation points, it also includes: The core electron temperature of the plasma and the electron temperatures of the plurality of discrete radiation points are obtained, wherein the core electron temperature is matched with the specified heavy metal; When the electron temperature matches the core electron temperature, the plurality of discrete radiation points are determined to satisfy the radiation acquisition conditions.

6. The method according to claim 1 or 2, wherein, After the control magnetic perturbation device shrinks the unresolved transition array radiation into multiple discrete radiation points, it also includes: If the plurality of discrete radiation points do not meet the radiation acquisition conditions, at least one of the incident rate of the specified heavy metal, the electromagnetic wave frequency of the plasma, and the excitation intensity of the magnetic disturbance device is adjusted until the plurality of discrete radiation points meet the radiation acquisition conditions.

7. An extreme ultraviolet radiation source assembly, comprising a magnetic confinement device, a heavy metal injection device, a magnetic disturbance device, and an optical device; The magnetic confinement device is used to generate plasma; The heavy metal injection device is used to inject a specified heavy metal into the magnetic confinement device when the plasma meets the preset injection conditions, so that the specified heavy metal forms an unresolved transition array radiation in the magnetic zero point region. The magnetic perturbation device is used to shrink the unresolved transition array radiation into multiple discrete radiation points; The optical device is used to collect extreme ultraviolet radiation based on the plurality of discrete radiation points when the radiation collection conditions are met.

8. The component according to claim 7, wherein, The magnetic confinement device includes a tokamak, which includes a vacuum chamber, a magnet, and a current actuator. The vacuum chamber is used to contain the plasma; The magnet is used to generate a magnetic field to confine the plasma in the vacuum chamber. The current driver is used to drive current in the plasma.

9. The component according to claim 7, wherein, The component operates in a boundless local mode state, which is maintained based on at least one of improved constraint mode, quiet high constraint mode, and edge local mode suppression.

10. The component according to claim 7, wherein, The magnetic disturbance device includes at least one of the following: a radial current bar array, a resonant magnetic disturbance saddle coil group, a circumferential magnetic field ripple modulation coil, and a ferromagnetic insert.

11. The component according to claim 7, wherein, The heavy metal injection device includes at least one of a vapor nozzle injection device, a liquid metal pool, a laser ablation device, a gas valve injection device, and a solid particle injection device.

12. The component according to claim 7, wherein, The optical device includes multiple sets of multilayer film collecting mirrors and light output ports corresponding to the multilayer film collecting mirrors, with each multilayer film collecting mirror corresponding to a discrete radiation point.

13. The component of claim 12, wherein, The light output port is provided with an intermediate focus module, which includes a differential pump, a magnetic deflection plate, a gas injection port, and a shutter. The differential pump is used to maintain the vacuum pressure difference between the light output port and the optical path; The magnetic deflection plate is used to deflect charged particles traveling from the plasma direction; The gas injection port is used to inject buffer gas to intercept the neutral atoms of the specified heavy metal; The shutter is used to control the on / off state of the extreme ultraviolet radiation.

14. An optical system comprising an extreme ultraviolet radiation source assembly as described in any one of claims 7 to 13.

15. The system according to claim 14, wherein, The system also includes multiple optical application ports arranged around the extreme ultraviolet radiation source assembly, which are connected to at least one of an extreme ultraviolet lithography scanner, an beyond extreme ultraviolet lithography scanner, a photochemical mask inspection system, a soft X-ray microscope, and an X-ray inspection system.

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