Extreme ultraviolet light output method and device, computer equipment and storage medium

Abstract

The invention relates to the technical field of plasma EUV, in particular to an extreme ultraviolet light output method and device, computer equipment and a storage medium. The output method comprises the steps that an ionizable medium is provided for a working cavity, first energy is provided for the ionizable medium to pre-ionize the ionizable medium, and a first plasma group is generated; the temperature in the working cavity is detected at a preset frequency, and the growth rate of the temperature at the current moment compared with the previous moment is obtained; and when the growth rate is greater than or equal to the preset value, providing second energy, and completely ionizing the first plasma group at least by the second energy to generate a second plasma group so as to generate and output the extreme ultraviolet light beam. According to the invention, the technical problem that the time interval between pre-ionization and complete ionization is too long, so that the pre-ionized plasma is easy to recombine is solved. The extreme ultraviolet light output device, the computer equipment and the storage medium have the same beneficial effects as the extreme ultraviolet light output method.

Description

Technical Field

[0001] The present invention relates to the field of plasma EUV technology, and particularly to a method and apparatus for outputting extreme ultraviolet light, a computer device, and a storage medium.

Background Art

[0002] Extreme Ultra Violet Lithography (EUVL) is a new generation of lithography technology that uses extreme ultraviolet (EUV) wavelengths. Its wavelength is 13.5 nm, and it is used to plan the production of integrated circuit (IC) devices with a scale of 32 nm and below. To meet the requirements of EUVL, it is necessary to conduct in-depth research and development on light sources of Laser Produced Plasma (LPP) and Discharge Produced Plasma (DPP).

[0003] Existing technologies for forming plasma and radiating extreme ultraviolet light cannot accurately determine whether pre-ionization occurs. When the interval time between pre-ionization and complete ionization is too long, the plasma obtained by pre-ionization will recombine.

[0004] In this regard, avoiding the recombination of plasma between pre-ionization and complete ionization has become a major problem to be solved in the prior art.

Summary of the Invention

[0005] To solve the technical problem that the interval time between pre-ionization and complete ionization is too long, which easily leads to the recombination of pre-ionized plasma, the present invention provides a method and apparatus for outputting extreme ultraviolet light, a computer device, and a storage medium.

[0006] The solution of the present invention to solve the technical problem is to provide a method for outputting extreme ultraviolet light, and the output method includes:

[0007] Providing an ionizable medium to a working cavity, and providing a first energy to the ionizable medium to pre-ionize it to generate a first plasma cluster;

[0008] Detecting the temperature in the working cavity at a preset frequency, and obtaining the growth rate of the temperature at the current moment compared with the previous moment;

[0009] When the growth rate is greater than or equal to a preset value, providing a second energy, and at least completely ionizing the first plasma cluster by the second energy to generate a second plasma cluster, so as to generate and output an extreme ultraviolet light beam.

[0010] Preferably, the working cavity is a component of the electrodeless pinch system, which provides the first energy to pre-ionize the ionizable medium, and includes:

[0011] Providing the first energy in the electrodeless pinch system, intercepting part of the first energy to generate a leakage current, and the leakage current pre-ionizes the ionizable medium, and at least part of the ionizable medium is ionized to generate the first plasma cluster.

[0012] Preferably, at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including:

[0013] Applying the second energy to the position where the first plasma cluster is located;

[0014] Pausing the interception of the first energy within a preset delay time;

[0015] Under the combined action of the first energy and the second energy, the first plasma cluster is completely ionized to generate the second plasma cluster to produce the extreme ultraviolet light beam.

[0016] Preferably, at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including:

[0017] Within a preset delay time, pausing the interception of the first energy to form the second energy, or maintaining the interception of the first energy and applying the second energy to the position where the first plasma cluster is located;

[0018] Under the action of the second energy, the first plasma cluster is completely ionized to generate the second plasma cluster to produce the extreme ultraviolet light beam.

[0019] Preferably, after at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, it further includes:

[0020] Obtaining the optical field information when the second plasma cluster is generated;

[0021] Performing optical field transfer processing and signal processing on the optical field information to obtain image information;

[0022] Based on the image information, obtaining the radius or diameter of the second plasma cluster.

[0023] The present invention also provides an extreme ultraviolet light output device for implementing the above extreme ultraviolet light output method, and the output device includes:

[0024] A working cavity for generating the extreme ultraviolet light beam;

[0025] A detection unit that detects the temperature in the working cavity at a preset frequency and obtains the growth rate of the temperature at the current moment compared to the previous moment;

[0026] An energy supply unit for providing the first energy and / or the second energy;

[0027] A beam output component is correspondingly arranged at the output end of the working cavity, and the beam output component is used to output the extreme ultraviolet beam generated by the working cavity.

[0028] Preferably, the working cavity is a component of an electrodeless pinch system, and the temperature detection component includes an infrared thermal imager correspondingly arranged for the electrodeless pinch system.

[0029] Preferably, the temperature measurement range of the infrared thermal imager is from -20°C to 2000°C, and the thermal sensitivity rate is from 30mK to 80mK.

[0030] The present invention also provides a computer device, including a memory and a processor. The memory is used to store a computer program, and the processor is used to execute the computer program to implement the above extreme ultraviolet light output method.

[0031] The present invention also provides a computer-readable storage medium, on which computer program instructions are stored. The computer program instructions, when executed by a processor, implement the above extreme ultraviolet light output method.

[0032] Compared with the prior art, an extreme ultraviolet light output method, device, computer device and storage medium provided by the present invention have the following advantages:

[0033] 1. The embodiment of the present invention provides an extreme ultraviolet light output method. The output method includes: providing an ionizable medium into the working cavity, providing a first energy to the ionizable medium to pre-ionize it, generating a first plasma cluster; detecting the temperature in the working cavity at a preset frequency and obtaining the growth rate of the temperature at the current moment compared to the previous moment; when the growth rate is greater than or equal to a preset value, providing a second energy, and at least completely ionizing the first plasma cluster by the second energy to generate a second plasma cluster, so as to generate and output an extreme ultraviolet beam.

[0034] It can be understood that the initial temperature in the working cavity is determined by the ambient temperature in the cavity. When the ambient temperature rises rapidly, it indicates that the pre-ionization process is occurring. By detecting the temperature in the working cavity, it is possible to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for performing complete ionization.

[0035] It should be noted that there is an uncontrollable delay time between the pre-ionization and the complete ionization processes. If the delay time is too long, the pre-ionized plasma will recombine. Therefore, this time will affect the conversion efficiency (CE) of extreme ultraviolet light radiation. Among them, the temperature in the detection working cavity can be specifically measured by an infrared detector.

[0036] The technical solution of the present invention controls the action time of the energy by observing the pre-ionization. In this way, the formed extreme ultraviolet light has higher brightness and stronger stability, and is a better mask detection light source.

[0037] 2. The extreme ultraviolet light output method provided by the embodiment of the present invention. The working cavity is a part of an electrodeless pinch system, and provides a first energy for the ionizable medium to pre-ionize, including: providing a first energy in the electrodeless pinch system, intercepting part of the first energy to generate a leakage current, and the leakage current pre-ionizes the ionizable medium, and at least part of the ionizable medium is ionized to generate a first plasma cluster.

[0038] As a preferred solution of the embodiment of the present invention, the above first energy is a preset electric pulse. It can be understood that the preset electric pulse acts on the ionizable medium, enabling the ionizable medium to perform the pre-ionization process. The pre-ionization process specifically obtains the first plasma cluster by changing the state of the ionizable medium. This process is to prepare for the subsequent complete ionization of the first plasma cluster to obtain a second plasma cluster with a higher valence state. It should be noted that compared with the solution without pre-ionization, the actual CE value of the technical solution of the present invention is higher.

[0039] 3. The extreme ultraviolet light output method provided by the embodiment of the present invention. At least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including: applying a second energy to the position where the first plasma cluster is located; pausing the interception of the first energy within a preset delay time; and completely ionizing the first plasma cluster under the combined action of the first energy and the second energy to generate a second plasma cluster to produce an extreme ultraviolet light beam.

[0040] As one of the preferred solutions of the embodiment of the present invention, the above first energy is a preset electric pulse and the second energy is a preset pulsed laser. It can be understood that the function of the preset pulsed laser is to act on the first plasma cluster together with the removed intercepted preset electric pulse. The first plasma cluster is a plasma with a low valence state, so that its size is further pinched. Compared with compressing the plasma solely by laser or electric pulse, the energy required for this solution is lower and it is easier to implement technically. The purpose of adding the pulsed laser is to utilize the radiation pressure (i.e., light pressure) of the laser to interact with the plasma to improve the output power of the extreme ultraviolet light.

[0041] 4. The extreme ultraviolet light output method provided by the embodiments of the present invention fully ionizes the first plasma cluster by at least a second energy to generate a second plasma cluster, including: within a preset delay time, pausing the interception of the first energy to form the second energy, or maintaining the interception of the first energy and applying the second energy to the position where the first plasma cluster is located; under the action of the second energy, fully ionizing the first plasma cluster to generate a second plasma cluster to produce extreme ultraviolet light beams.

[0042] As one of the preferred solutions of the embodiments of the present invention, both the above-mentioned first energy and second energy are preset electrical pulses. It can be understood that pausing the interception of the first energy to form the second energy, and maintaining the interception of the first energy and applying the second energy to the position where the first plasma cluster is located. Among them, the former only applies a preset electrical pulse once during the pre-ionization process, while the latter maintains the interception of the preset electrical pulse during the pre-ionization process and applies a second preset electrical pulse without interception before the full ionization process.

[0043] This solution uses a preset electrical pulse to change the state of the plasma, reducing the number of times of plasma recombination while improving the conversion efficiency of extreme ultraviolet light beams. Compared with the solution that only uses a laser, this solution is easier to implement technically, does not require an external system for generating pulsed lasers, and is convenient for system integration; compared with the solution of directly applying a preset electrical pulse without interception, this solution can reduce the cost of generating and outputting extreme ultraviolet light beams.

[0044] 5. The extreme ultraviolet light output method provided by the embodiments of the present invention, after at least fully ionizing the first plasma cluster by a second energy to generate a second plasma cluster, further includes: obtaining the light field information when the second plasma cluster is generated; performing light field transfer processing and signal processing on the light field information to obtain image information; obtaining the radius or diameter of the second plasma cluster based on the image information.

[0045] It can be understood that the technical solution of the present invention first obtains the light field information when the first plasma cluster is fully ionized to generate the second plasma cluster, and then performs light field transfer processing and signal processing on the light field information to obtain image information, realizing obtaining the radius or diameter size of the plasma cluster by using imaging detection means during the full ionization process, so as to facilitate subsequent iterative optimization of the system.

[0046] 6. The embodiment of the present invention further provides an extreme ultraviolet light output device for implementing the above extreme ultraviolet light output method. The output device includes: a working cavity for generating extreme ultraviolet light beams; a detection unit for detecting the temperature in the working cavity at a preset frequency to obtain the growth rate of the temperature at the current moment compared with the previous moment; an energy supply unit for providing the first energy and / or the second energy; and a light beam output assembly correspondingly arranged at the output end of the working cavity, and the light beam output assembly is used for outputting the extreme ultraviolet light beams generated by the working cavity.

[0047] It can be understood that the working cavity and the light beam output assembly correspondingly arranged at the output end of the working cavity are respectively responsible for generating extreme ultraviolet light beams and outputting extreme ultraviolet light beams. The detection unit is responsible for detecting the temperature in the working cavity at a preset frequency to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for performing complete ionization, while the energy supply unit is responsible for providing energy to perform the pre-ionization and / or complete ionization process in the working cavity.

[0048] 7. In the extreme ultraviolet light output device provided by the embodiment of the present invention, the working cavity is an electrodeless pinch system, and the temperature detection component includes an infrared thermal imager correspondingly arranged for the electrodeless pinch system; the temperature measurement range of the infrared thermal imager is -20°C to 2000°C, and the thermal sensitivity rate is 30 mK to 80 mK.

[0049] It can be understood that the function of the infrared thermal imager is to detect the temperature of the plasma after pre-ionization occurs in the electrodeless pinch system, that is, to detect the temperature inside the electrodeless pinch system, and convert the temperature signal into an image that can be visually distinguished by humans, and the temperature value is calculated by the corresponding software provided by the infrared thermal imager. An increase in temperature indicates that the pre-ionization process is ongoing in the electrodeless pinch system.

[0050] It should be noted that the specific types of the infrared thermal imager include, but are not limited to, portable infrared thermal imagers, digital thermal imagers, and online infrared thermal imagers, as long as their temperature measurement ranges and thermal sensitivity rates meet the requirements.

[0051] 8. The embodiment of the present invention further provides a computer device, including a memory and a processor. The memory is used for storing a computer program, and the processor is used for executing the computer program to implement the above extreme ultraviolet light output method.

[0052] This computer device has the same beneficial effects as the above extreme ultraviolet light output method, and will not be elaborated here.

[0053] 9. The embodiment of the present invention further provides a computer-readable storage medium, on which computer program instructions are stored, and the computer program instructions implement the above extreme ultraviolet light output method when executed by a processor.

[0054] This computer-readable storage medium has the same beneficial effects as the above-mentioned extreme ultraviolet light output method, which will not be elaborated here.

Explanation of the Drawings

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0056] Figure 1 It is a schematic flowchart of an extreme ultraviolet light output method provided by the first embodiment of the present invention.

[0057] Figure 2 It is a schematic flowchart of the process in which the first energy and the second energy in an extreme ultraviolet light output method provided by the first embodiment of the present invention completely ionize the first plasma cluster to generate the second plasma cluster.

[0058] Figure 3 It is a timing diagram during the pre-ionization and complete ionization processes in an extreme ultraviolet light output method provided by the first embodiment of the present invention.

[0059] Figure 4 It is a schematic flowchart of the process after at least the second energy completely ionizes the first plasma cluster to generate the second plasma cluster in an extreme ultraviolet light output method provided by the first embodiment of the present invention.

[0060] Figure 5 It is a schematic framework diagram of an extreme ultraviolet light output device provided by the second embodiment of the present invention.

[0061] Figure 6 It is a schematic structural diagram of a light source generation component and a discharge chamber in an extreme ultraviolet light output device provided by the second embodiment of the present invention.

[0062] Figure 7 It is a schematic framework diagram of a computer device provided by the third embodiment of the present invention.

[0063] Figure 8 It is a schematic framework diagram of a computer-readable storage medium provided by the fourth embodiment of the present invention.

[0064] Explanation of the drawing reference numerals:

[0065] 1. Extreme ultraviolet light output device; 11. Working cavity; 12. Detection unit; 121. Infrared thermal imager; 13. Energy supply unit; 14. Beam output component; 15. Light source generation component;

[0066] 2. Discharge chamber; 21. First magnetic core; 22. Second magnetic core; 23. Central hole; 24. Through hole; 25. Plasma ring; 26. Preset position; 27. Pulsed laser; 28. EUV radiation;

[0067] 3. Computer device; 31. Memory; 311. Computer program; 32. Processor;

[0068] 4. Computer-readable storage medium; 41. Computer program instructions.

Detailed implementation manners

[0069] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and implementation examples. It should be understood that the specific implementation examples described herein are only used to explain the present invention and are not used to limit the present invention.

[0070] In the embodiments provided by the present invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0071] It should be understood that the term "one embodiment" or "an embodiment" mentioned throughout the specification means that a specific feature, structure or characteristic related to the embodiment is included in at least one embodiment of the present invention. Therefore, the appearances of the phrase "in one embodiment" or "in an embodiment" throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0072] In various embodiments of the present invention, it should be understood that the magnitudes of the sequence numbers of the above processes do not necessarily mean the inevitable sequence of execution. The execution sequence of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0073] The flowcharts and block diagrams in the accompanying drawings of the present invention illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a part of code that contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, which is determined based on the functions involved. It should be particularly noted that each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0074] The present invention realizes an extreme ultraviolet light output method by using an imaging detection method. The imaging detection is mainly used to determine whether pre-ionization occurs in the working cavity, so as to control the action time of the pulsed laser and improve the synchronization between the pulsed laser and the working cavity.

[0075] One of the technical solutions provided by the present invention can apply a pulsed laser during the time interval between pre-ionization and complete ionization, and use the leakage current generated by pre-ionization and the pulsed laser to change the state of the plasma, so as to avoid the recombination of the plasma and improve the conversion efficiency (CE value) of the extreme ultraviolet light beam.

[0076] Another technical solution provided by the present invention can, between pre-ionization and complete ionization, use a high-current pulse to sequentially pre-ionize and completely ionize the ionizable medium to change the state of the plasma, reduce the number of times of plasma recombination while increasing the CE value of the extreme ultraviolet light beam, and reduce the cost of generating and outputting the extreme ultraviolet light beam.

[0077] The technical solutions involved in the present invention will be described in detail below.

[0078] Please refer to Figure 1 , the first embodiment of the present invention provides an extreme ultraviolet light output method, and the output method includes:

[0079] S1: Provide an ionizable medium to the working cavity, provide a first energy to the ionizable medium to pre-ionize it, and generate a first plasma cluster;

[0080] S2: Detect the temperature in the working cavity at a preset frequency, and obtain the growth rate of the temperature at the current moment compared with the previous moment;

[0081] S3: When the growth rate is greater than or equal to a preset value, provide a second energy. At least the second energy is used to completely ionize the first plasma cluster to generate a second plasma cluster, so as to generate and output an extreme ultraviolet beam.

[0082] Specifically, in step S1, the ionizable medium includes but is not limited to Xe.

[0083] It can be understood that the radiation of extreme ultraviolet light with a wavelength of 13.5 nm comes from the spontaneous emission transition of atoms or ions. Currently, there are mainly four media for generating 13.5 nm radiation: Li, O, Xe, and Sn. And the extreme ultraviolet beam mainly uses Xe and Sn media with relatively large atomic weights, and their radiation sources near 13.5 nm are relatively rich. However, since Sn is a solid at room temperature and needs to be vaporized before complete ionization, while Xe is an inert gas and has the advantage of generating fewer fragments, the present invention mainly uses Xe as the ionizable medium.

[0084] When Xe is used as the ionizable medium, the generated first plasma cluster at least includes Xe + and Xe 2+ These two low-valence Xe plasma. Among them, the pre-ionization process in step S1 only needs to simply ionize to generate +1 or +2 valence Xe plasma; the second plasma cluster includes Xe 9+ and Xe 10+ , the Xe in the second plasma cluster 9+ cannot radiate extreme ultraviolet light of 13.5 nm, while the particles of Xe 10+ ions located in the upper energy level 4d 7 5p transition to the lower energy level 4d 8 , they radiate extreme ultraviolet radiation light with a wavelength of 13.5 nm. Therefore, the target high valence state to be obtained is +10 valence. Since directly ionizing the ionizable medium Xe to Xe 10+ requires relatively high energy, the above-mentioned pre-ionization and complete ionization processes are needed.

[0085] Particularly, in the first embodiment of the present invention, the selection of the ionizable medium, and the valence states of the first plasma cluster and the second plasma cluster will not be elaborated too much hereafter.

[0086] In step S2, the initial temperature in the working cavity is determined by the ambient temperature in the vacuum cavity (preferably, the working cavity is a part of the electrodeless pinch system, and the initial temperature is basically equal to the indoor temperature where the electrodeless pinch system is located). When the ambient temperature rises rapidly, it indicates that the pre-ionization process is occurring. By detecting the temperature in the working cavity, it is possible to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for at least the second energy to act on the first plasma cluster to perform complete ionization. Through this design, it is possible to ensure the stable supply of the second energy between pre-ionization and complete ionization.

[0087] Specifically, the basic definition of the preset value is: the growth rate of the temperature at a certain moment in the vacuum cavity compared to the temperature at the previous moment when the pre-ionization process is occurring in the working cavity; as a preferred embodiment of the present invention, the preset value is 50%. The present invention detects and records the temperature of the working cavity. When it is found that the temperature at the current moment has changed suddenly compared to the previous moment, that is, the temperature at the current moment has increased by 50% or more compared to the temperature at the previous moment, it indicates that the pre-ionization process is occurring.

[0088] It should be noted that the present invention only gives one embodiment for illustration. The above preset value can be set according to the actual situation, as long as it can determine that the pre-ionization process is occurring. Any modifications, equivalent replacements, and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

[0089] For the technical solution involved in the present invention, when the set preset value is too high, it may be the case that the growth rate of the temperature cannot be greater than or equal to the preset value throughout the pre-ionization process, or the leakage current generated during the pre-ionization process may be insufficient when the growth rate of the temperature is greater than or equal to the preset value, resulting in plasma recombination; when the set preset value is too low, the pre-ionization process may not have occurred yet. For example, the situation where the growth rate of the temperature is greater than or equal to the preset value may be caused by the increase in the ambient temperature.

[0090] Optionally, in step S2, an infrared thermal imager can be used to detect the temperature in the working cavity at a preset frequency. Among them, the preset frequency can be set according to the device parameters of the infrared thermal imager. The technical solution of the present invention does not limit the preset frequency, and the preset frequency is set according to the actual mutation of the temperature when the pre-ionization process occurs.

[0091] Optionally, detecting the temperature in the working cavity can, in addition to determining whether the pre-ionization process occurs, continue to detect the temperature after it is determined that the pre-ionization has occurred.

[0092] When the temperature detection device is an infrared thermal imager, during the complete ionization process, the second plasma cluster contains more valence states and complex ionic components. The temperature detected by the infrared thermal imager will be much higher than that during pre-ionization and may exceed the range. If the device is still used after exceeding the range, it may cause damage. Therefore, when the temperature reaches the range, temperature detection needs to be stopped, and at this time, the complete ionization process may be occurring.

[0093] It should be noted that by detecting the temperature of the working cavity within the range, the parameters of the first energy and the second energy can be dynamically adjusted to ensure the generation of a better extreme ultraviolet light beam.

[0094] Furthermore, it should be noted that the delay time is between the pre-ionization and the complete ionization processes. Specifically, it refers to the buffer time during which the second energy does not act after the start of pre-ionization and before the start of complete ionization. This delay time is uncontrollable. If the delay time is too long, the pre-ionized plasma will recombine. Therefore, this time will affect the CE value of the extreme ultraviolet light radiation.

[0095] The technical solution of the present invention observes pre-ionization to control the action time of the energy. The extreme ultraviolet light formed in this way has higher brightness and stronger stability and is a better mask detection light source.

[0096] Specifically, the working cavity is a part of the electrodeless pinch system, which provides the first energy for the ionizable medium to pre-ionize, specifically including:

[0097] Providing the first energy in the electrodeless pinch system, intercepting part of the first energy to generate a leakage current, and the leakage current pre-ionizes the ionizable medium. At least part of the ionizable medium is ionized to generate the first plasma cluster.

[0098] As a preferred solution of the first embodiment of the present invention, the above-mentioned first energy is a preset electric pulse. It should be noted that during the pre-ionization process, part of the preset electric pulse needs to be intercepted to preliminarily ionize the ionizable medium into a low-valence state plasma. At this time, for the intercepted preset electric pulse, the current amplitude is 25 kA to 40 kA, and the pulse width is 3 μs to 10 μs.

[0099] It can be understood that the preset electric pulse acts on the ionizable medium, causing the ionizable medium to perform the pre-ionization process. The pre-ionization process specifically obtains the first plasma cluster by changing the state of the ionizable medium. This process is to prepare for the subsequent complete ionization of the first plasma cluster to obtain a higher-valence second plasma cluster.

[0100] It should be noted that, compared with the scheme without pre-ionization, the actual CE value of the technical scheme of the present invention is higher. Through this design, the electrons generated during the pre-ionization process can cooperate in the energy transfer when the second energy is provided subsequently, so that at least the second energy can further accelerate and enter the plasma system.

[0101] Specifically, the steps of the method involved in the present invention are implemented in an electrodeless pinch system. The electrodeless pinch system is responsible for ionizing the ionizable medium into plasma. In this system, specifically, a device similar to a "magnetic switch" is used to generate a pre-current and a main current. The energy storage device (such as a capacitor, an inductor, etc.) at the front end charges the electrodeless pinch system. The capacitor generates a leakage current during the charging process, and the leakage current directly acts on the ionizable medium to cause preliminary ionization, generating an initial plasma. The initial plasma converges to form a first plasma cluster.

[0102] It should be noted that after the initial plasma converges to form a first plasma cluster, the plasma cluster can also generate a Z-pinch effect through the Lorentz force applied by a preset electric pulse, so that the size of the first plasma cluster is further pinched until its radius reaches the minimum value. At this time, the position of the first plasma cluster including low-valence state plasma is: the position where the plasma cluster with the minimum radius combines with the second energy; for the plasma at this position, its pinched radius reaches the minimum value, and the temperature and density reach the maximum value.

[0103] Further, please refer to Figure 2 , at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including:

[0104] S31: Apply the second energy to the position where the first plasma cluster is located;

[0105] S32: Pause intercepting the first energy within a preset delay time, and under the combined action of the first energy and the second energy, completely ionize the first plasma cluster to generate a second plasma cluster to produce extreme ultraviolet light beams.

[0106] As a preferred scheme of the embodiment of the present invention, the above-mentioned first energy is a preset electric pulse, and the second energy is a preset pulsed laser.

[0107] Among them, in step S3a, the energy of the applied preset pulsed laser is 3 mJ to 10 mJ, and the irradiance is 5*10 9 W / cm 2 to 9*10 9 W / cm 2; In step S3b, the interception of the preset electrical pulse is paused, that is, the preset electrical pulse is completely released. At this time, the current amplitude of the preset electrical pulse is 25 kA to 40 kA, and the pulse width is 100 ns to 180 ns.

[0108] Understandably, in step S3c, the role of the preset pulsed laser is to act on the first plasma cluster together with the preset electrical pulse whose interception is removed, so that its size is further pinched; compared with compressing the plasma using only the laser or the electrical pulse alone, the energy required for this solution is lower and it is easier to implement technically. The purpose of adding the pulsed laser is to utilize the radiation pressure (i.e., light pressure) of the laser to interact with the plasma and increase the output power of extreme ultraviolet light.

[0109] Through the above steps, stable absorption of the pulsed laser and the plasma cluster can be achieved to generate extreme ultraviolet light with better stability, and it can save more energy and improve the synchronization between the plasma and the pulsed laser.

[0110] Optionally, the preset pulsed laser is used as the second energy. The processing required for the preset pulsed laser compared to the initial pulsed laser includes but is not limited to shaping, beam expansion, and focusing. Through the above processing, a light spot with higher power and uniform energy distribution can be obtained. Such a light beam can quickly react to generate stable extreme ultraviolet light radiation after acting on the plasma cluster.

[0111] It should be noted that by using the preset pulsed laser to act on the low-valence state plasma in the first plasma cluster to increase the repetition frequency of EUV radiation, the specific solution involved in the present invention has low requirements for parameters such as the energy and irradiance of the laser. Therefore, there are many types of lasers that can be selected; optionally, the light source of the preset pulsed laser includes but is not limited to solid-state lasers, excimer lasers, fiber lasers, and CO2 lasers, as long as the above energy (3 mJ to 10 mJ) and irradiance (5*10 9 W / cm 2 to 9*10 9 W / cm 2 ) conditions are met.

[0112] Optionally, when providing the preset pulsed laser, a lens is used to focus on the position where the first plasma cluster is located. The laser is focused after passing through the lens and then acts on the low-valence state plasma in the first plasma cluster to compress these plasmas to avoid recombination. Through this design, the recombination of the plasma can be further avoided.

[0113] Optionally, the second energy can also be a laser double pulse. The system for realizing the laser double pulse includes two lasers and a beam combining device. The laser is preferably a Nd:YAG laser, with a maximum pulse energy of 180 mJ, a pulse duration Δt = 18 ns, and a maximum pulse repetition frequency of 10 Hz; the beam combining device includes a mirror, a dichroic mirror, and a focusing lens.

[0114] Among them, one laser pulse passes through the mirror to deflect the optical path and then combines with the other laser. Therefore, there is a certain sequence between the two laser pulses before beam combination. By adjusting the emission time between the two laser pulses, the repetition frequency of the combined laser is increased. The laser double pulse formed after beam combination interacts with the first plasma cluster generated by pre-ionization after passing through the focusing lens, and radiates extreme ultraviolet light.

[0115] It can be understood that compared with the case of single-path pulsed laser, in the laser double pulse scheme, the repetition frequency of the laser is higher, and correspondingly, the conversion efficiency of extreme ultraviolet light radiation is improved.

[0116] Please refer to Figure 3 , in this scheme, the processes of pre-ionization and complete ionization are as follows:

[0117] In the time period from t0 to t1, a preset electrical pulse is input into the electrodeless pinch system, and the preset electrical pulse is intercepted to generate a leakage current. The leakage current pre-ionizes the ionizable medium in the surrounding space into the first plasma cluster, that is, a plasma in a low valence state; among them, the leakage current corresponding to the intercepted preset electrical pulse can reach up to i1 at most.

[0118] In the time period from t1 to t3, a preset pulsed laser is applied to the surface of the first plasma cluster to avoid the recombination of the plasma. That is to say, the above-mentioned preset delay time is the time period from t0 to t2. If no laser is applied in the time period from t1 to t2, the recombination of the plasma is more likely to occur; it should be noted that when no laser is applied in the time period from t1 to t2 and only the preset electrical pulse is used, the processes of pre-ionization and complete ionization can actually be achieved, but it is more difficult to avoid plasma recombination. Applying the laser at time t1 is to avoid this situation.

[0119] At time t2, the interception of the preset electrical pulse by the electrodeless pinch system is removed, and the preset electrical pulse directly discharges the low valence state plasma cluster. The low valence state plasma in it generates a Z-pinch effect due to the action of the Lorentz force, so as to obtain a completely ionized plasma cluster and radiate an extreme ultraviolet beam of 13.5 nm. The current of the preset electrical pulse can reach up to i2 at most in the time period from t1 to t3.

[0120] As another alternative embodiment, at least the second energy is used to completely ionize the first plasma cluster to generate a second plasma cluster, including:

[0121] Within a preset delay time, intercepting the first energy is paused to form the second energy, or the interception of the first energy is maintained and the second energy is applied to the position where the first plasma cluster is located. Under the action of the second energy, the first plasma cluster is completely ionized to generate a second plasma cluster, so as to generate an extreme ultraviolet beam.

[0122] As a preferred solution of the embodiment of the present invention, both the above-mentioned first energy and second energy are preset electric pulses.

[0123] It can be understood that intercepting the first energy is paused to form the second energy, and the interception of the first energy is maintained and the second energy is applied to the position where the first plasma cluster is located. Among them, the former only applies a preset electric pulse once during the pre-ionization process, while the latter maintains the interception of the preset electric pulse during the pre-ionization process and applies a second preset electric pulse without interception before the complete ionization process.

[0124] This solution uses a preset electric pulse to change the state of the plasma, reducing the number of times of plasma recombination while improving the conversion efficiency of the extreme ultraviolet beam.

[0125] Compared with the solution that only uses a laser alone, this solution is easier to implement technically, does not require an external system for generating pulsed lasers, and is convenient for system integration.

[0126] Compared with the solution of directly applying a preset electric pulse without interception, this solution can reduce the cost of generating and outputting an extreme ultraviolet beam.

[0127] Please refer to Figure 4 , as another alternative embodiment, after at least the second energy is used to completely ionize the first plasma cluster to generate a second plasma cluster, it further includes:

[0128] S3a: Obtain the optical field information when the second plasma cluster is generated;

[0129] S3b: Perform optical field transfer processing and signal processing on the optical field information to obtain image information;

[0130] S3c: Obtain the radius or diameter of the second plasma cluster based on the image information.

[0131] It can be understood that the technical solution of the present invention first obtains the optical field information when the first plasma cluster is completely ionized to generate the second plasma cluster, and then performs optical field transfer processing and signal processing on the optical field information to obtain image information, realizing the use of imaging detection means to obtain the radius or diameter size of the plasma cluster during the complete ionization process, so as to facilitate subsequent iterative optimization of the system.

[0132] Among them, in step S3a, the optical field information when the second plasma cluster is generated is obtained, specifically by means of optical imaging.

[0133] As a preferred implementation of the first embodiment of the present invention, in step S3c, the image information can be clearly presented on the imaging device, and based on this image information, the radius or diameter of the second plasma cluster can be obtained. In the process, the diameter range of the obtained second plasma cluster is 250 μm to 1000 μm; preferably, when the pinch equilibrium is reached, that is, when the second plasma cluster stably radiates extreme ultraviolet light beams, the diameter of the second plasma cluster is 800 μm.

[0134] It should be noted that if the diameter parameter of the second plasma cluster obtained through the above steps is outside the diameter range, it indicates that the system cannot yet obtain stable extreme ultraviolet light beams and the system needs to be further optimized.

[0135] Furthermore, in step S3b, after obtaining the optical field information by means of optical imaging, the optical field transfer processing performed on the optical field information includes filtering, amplifying, and / or focusing. It can be understood that the optical field transfer processing is a series of processing processes including but not limited to filtering, amplifying, and focusing performed on the optical field information when the second plasma cluster is generated, and the above filtering, amplifying, and focusing can only be performed by means of optical imaging.

[0136] After the optical field transfer processing is completed, signal processing is performed on the optical field information. The signal processing includes converting the optical signal of the optical field information into an electrical signal by an imaging detector.

[0137] Among them, in the process of optical field transfer processing, the role of filtering is to filter out the bands other than extreme ultraviolet light, the amplification process is to amplify the optical field information by using an objective lens, the role of focusing is to enable the optical field information to be finally clearly presented on the imaging detector, and the signal processing process is performed after the optical field transfer processing is completed. The optical signal of the optical field information is converted into an electrical signal by an imaging detector to obtain image information that can be used to obtain the radius or diameter of the second plasma cluster.

[0138] Optionally, filtering, amplification, and focusing can be achieved by a narrow-band filter, an objective lens, and a focusing lens respectively. The relevant parameters of the three can be selected according to the actual situation. The wavelength measured by the narrow-band filter can be Δλ = 13.5 nm ± 5 nm (i.e., only light within the wavelength range of 13.5 nm ± 5 nm can pass through the narrow-band filter). The magnification of the objective lens can be set to 2 times, and the imaging focal length of the focusing lens can be f = 300 mm. It can be understood that the present invention only gives an implementation manner for illustration. As long as image information that can be used to obtain the radius or diameter of the second plasma cluster can be obtained, any modifications, equivalent substitutions, and improvements made within the principle of the present invention should be included within the protection scope of the present invention.

[0139] As a preferred implementation manner of the first embodiment of the present invention, the process of performing optical field transfer processing on optical field information specifically includes filtering, amplification, and focusing. The optical field information formed by generating the second plasma cluster during the complete ionization process, after passing through the narrow-band filter, the objective lens, and the focusing lens in sequence, is signal-processed by the imaging detector to convert the optical signal of the optical field information into an electrical signal to obtain image information. The image information is clearly presented on the imaging device, and finally the parameters of the radius or diameter of the second plasma cluster are obtained.

[0140] It should be noted that if only filtering and amplification are performed during the optical field transfer processing and focusing is not performed, clear image information cannot be presented on the imaging device; if only amplification and focusing are performed during the optical field transfer processing and filtering is not performed, the light beams formed by the wavelength bands other than extreme ultraviolet light will interfere with the image information, ultimately resulting in inaccurate parameters of the radius or diameter of the second plasma cluster obtained finally.

[0141] Optionally, in step S3c, an imaging device is used to obtain image information. Specifically, the imaging device can use a semiconductor imaging device CCD (Charge Coupled Device), and CCD has the advantages of high sensitivity, resistance to strong light, small volume, long life, etc. After the above optical field transfer processing and signal processing are completed, the image information will finally be presented on the imaging device CCD.

[0142] Please refer to Figure 5 , the second embodiment of the present invention provides an extreme ultraviolet light output device 1 for implementing the above extreme ultraviolet light output method. The output device includes:

[0143] A working cavity 11 for generating an extreme ultraviolet light beam;

[0144] A detection unit 12 for detecting the temperature in the working cavity 11 at a preset frequency and obtaining the growth rate of the temperature at the current moment compared with the previous moment;

[0145] An energy supply unit 13 for providing the first energy and / or the second energy;

[0146] A light beam output component 14 correspondingly arranged at the output end of the working cavity 11, and the light beam output component 14 is used for outputting the extreme ultraviolet light beam generated by the working cavity 11.

[0147] Understandably, the working cavity 11 and the light beam output component 14 correspondingly arranged at the output end of the working cavity 11 are respectively responsible for generating the extreme ultraviolet light beam and outputting the extreme ultraviolet light beam, the detection unit 12 is responsible for detecting the temperature in the working cavity 11 at a preset frequency to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for performing complete ionization, and the energy supply unit 13 is responsible for providing energy to perform the pre-ionization and / or complete ionization process in the working cavity 11.

[0148] Further, the working cavity 11 is a component of an electrodeless pinch system.

[0149] For ease of understanding, please refer to Figure 6 , the present invention focuses on explaining the electrodeless pinch system. The electrodeless pinch system includes a discharge cavity 2, the ionizable medium is Xe, the discharge cavity 2 is used for discharging the ionizable medium and generating low-valence Xe plasma, and the plasma then converges to form a plasma cluster. A first magnetic core 21 and a second magnetic core 22 are arranged in the discharge cavity 2. The second magnetic core 22 has a high impedance and allows a small amount of leakage current to flow through, and is used for decomposing Xe gas into low-valence Xe plasma and maintaining its plasma state, thereby forming pre-ionization.

[0150] By the process of pre-ionizing Xe, the conversion rate of plasma EUV can be improved. During the capacitor charging process, a small amount of leakage current in the circuit is used to decompose the ionizable medium into low-valence plasma and maintain its plasma state, which can effectively improve the conversion efficiency of the plasma; in addition, the electrons generated during the pre-ionization process will transfer energy cooperatively under the action of the electric pulse, so that the energy is introduced into the plasma system in a faster way.

[0151] During this process, Xe is ionized and low-valence Xe plasma is generated. The first magnetic core 21 provides a magnetic field environment for the plasma to pinch the low-valence Xe plasma to a preset position 26.

[0152] Specifically, the Lorentz force generated by the magnetic field of the first magnetic core 21 and the electric field is greater than the thermal pressure of the plasma, so that the plasma is pinched inward. This process increases the collision probability between electrons and ions and between ions, and makes the temperature inside the plasma rise.

[0153] When the magnetic pressure and the thermal pressure are in balance, at a preset position 26 within the central hole 23, the pinch radius of the plasma at the preset position 26 can reach the minimum value, and the temperature and density reach the maximum values; a central hole 23 is provided on the first magnetic core 21, the first magnetic core 21 is arranged around the central hole 23, the second magnetic core 22 is located on the side of the first magnetic core 21 away from the central hole 23, and at least one through hole 24 is provided between the first magnetic core 21 and the second magnetic core 22. Xe forms a plasma ring 25 under the action of the first magnetic core 21 and the second magnetic core 22, and the plasma ring 25 passes through the through hole 24 and the central hole 23 respectively.

[0154] Please continue to refer to Figure 5 and Figure 6 , the extreme ultraviolet light output device 1 provided by the second embodiment of the present invention further includes a light source generating component 15. The output end of the light source generating component 15 is coaxially arranged with the central hole 23, and the pulsed laser 27 emitted by the light source generating component 15 enters from the receiving end of the central hole 23 and reacts with the plasma group in the central hole 23 to generate EUV radiation 28 and then exits from the emitting end.

[0155] It should be noted that the light source generating component 15 is coaxially arranged with the central hole 23, so that the output end of the light source generating component 15 is aligned with the preset position 26 in the electrodeless pinch system, which is convenient for the pulsed laser 27 generated by the light source generating component 15 to bombard the plasma group at the preset position 26 to generate EUV radiation 28.

[0156] Specifically, the working principle of the electrodeless pinch system is as follows: The DC power supply stores charges in the capacitor through the modulation circuit. The leakage current generated during this process ionizes the Xe gas into +1 and +2 valence ions. When the magnetic switch is saturated, the energy pulse supplies energy to the plasma in the system in a mutual inductance manner, and continuously compresses the plasma by its own magnetic field to make it radiate EUV.

[0157] Among them, the Xe gas discharge to generate 13.5 nm extreme ultraviolet radiation light belongs to the transition of Xe 10+ ion 4d 7 5p energy level to 4d 8 energy level. The nuclear charge number of the Xe atom is 54. Ignoring the transition process of the metastable state, the process of Xe 10+ generating 13.5 nm extreme ultraviolet radiation is as follows: The Xe 7 ion in the ground state 4d 10+ 5s undergoes a transition to a higher energy level due to electron collision excitation. When it transitions to a higher energy level above the energy level 4d 7 5p, the residence time is very short, and then it quickly transitions to the energy level 4d 7 5p through radiation or non-radiation. When the particles in the upper energy level 4d 7 5p transition to the lower energy level 4d8 When transitioning, extreme ultraviolet radiation with a wavelength of 13.5 nm is radiated.

[0158] It should be noted that the electrodeless pinch system can squeeze the plasma to a certain spatial position. At this time, the plasma has the characteristics of a small radius and a high density, which is conducive to improving the synchronization between the plasma and the pulsed laser 27 and realizing the stable output of the EUV light source. At the same time, in this embodiment, the pre-ionization process of the electrodeless pinch system effectively improves the conversion efficiency of the plasma from a low valence state to a high valence state; in addition, the electrons generated during this process will also cooperate to transfer energy under the action of the electric pulse, enabling the energy to be transmitted into the plasma system in a faster manner.

[0159] Specifically, please continue to refer to Figure 5 , as the preferred implementation manner of the second embodiment of the present invention, the detection unit 12 includes an infrared thermal imager 121 arranged corresponding to the electrodeless pinch system.

[0160] It should be noted that the initial temperature before the pre-ionization process is determined by the ambient temperature in the vacuum chamber of the electrodeless pinch system, and the initial temperature is basically equal to the indoor temperature where the electrodeless pinch system is placed.

[0161] It can be understood that the function of the infrared thermal imager 121 is to detect the temperature of the plasma after pre-ionization occurs in the electrodeless pinch system, that is, to detect the temperature inside the electrodeless pinch system, convert the temperature signal into an image that can be visually distinguished by humans, and calculate the temperature value by the corresponding software provided by the infrared thermal imager 121. The technical solution of the present invention uses the infrared thermal imager 121 to detect and record the temperature of the electrodeless pinch system at the current moment. When it is found that the temperature at the current moment has changed suddenly compared with the previous moment, that is, the temperature has increased by 50% or more, it indicates that the pre-ionization process is in progress in the electrodeless pinch system.

[0162] Among them, the temperature measurement range of the infrared thermal imager 121 is from -20°C to 2000°C, and the thermal sensitivity rate is from 30 mK to 80 mK.

[0163] As the preferred implementation of the second embodiment of the present invention, the type of the infrared thermal imager 121 is an online infrared thermal imager, its frame rate is 30 Hz, the image output bandwidth is 1.8 Mb, the temperature measurement range of the device is from -20°C to 2000°C, the temperature measurement accuracy is ±1°C - 5°C, and the thermal sensitivity rate is less than or equal to 30 mK.

[0164] It should be noted that the specific types of the infrared thermal imager 121 include, but are not limited to, portable infrared thermal imagers, digital thermal imagers, and online infrared thermal imagers. As long as their temperature measurement ranges and thermal sensitivity rates meet the requirements, the specific type of the infrared thermal imager 121 can be set according to actual needs. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present invention shall be included within the protection scope of the present invention.

[0165] Please refer to Figure 7 , a third embodiment of the present invention provides a computer device 3, including a memory 31 and a processor 32. The memory 31 is used to store a computer program 311, and the processor 32 is used to execute the computer program 311 to implement the above-mentioned extreme ultraviolet light output method.

[0166] It can be understood that when the computer device 3 in the third embodiment of the present invention runs, when the processor 32 executes the computer program 311, the extreme ultraviolet light output method described in the above first embodiment can be implemented.

[0167] It should be noted that the computer device 3 provided in the third embodiment of the present invention has the same beneficial effects as the above-mentioned extreme ultraviolet light output method.

[0168] Specifically, the computer device 3 can be a computer device applied to the field of plasma EUV technology, including but not limited to controlling a preset delay time, partially intercepting a preset electrical pulse, and pausing the interception of a preset electrical pulse. Details are not described here. In theory, the steps involving the technical solution of the present invention can all be realized through the participation and control of the computer device 3, and the relevant parameters involved can also be adjusted correspondingly through the computer device 3. Among them, the relevant parameters include but are not limited to parameters such as the energy and irradiance of the preset pulsed laser, and the current amplitude and pulse width of the preset electrical pulse.

[0169] Optionally, the processor 32 in the third embodiment of the present invention can be a general-purpose processor, and the general-purpose processor can be a microprocessor or any conventional processor, such as a central processing unit (CPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application.

[0170] Preferably, the method steps disclosed in the embodiments of the present application can be embodied as being executed by a hardware processor or by a combination of hardware and software modules in the processor.

[0171] Please refer to Figure 8, a fourth embodiment of the present invention provides a computer-readable storage medium 4, on which computer program instructions 41 are stored. When the computer program instructions 41 are executed by a processor, the above-mentioned extreme ultraviolet light output method is implemented.

[0172] It can be understood that computer program instructions 41 are stored in the computer-readable storage medium 4 in the fourth embodiment of the present invention, and the computer program instructions 41 can be called by a processor to execute an extreme ultraviolet light output method described in the first embodiment above.

[0173] It should be noted that the computer-readable storage medium 4 has the same beneficial effects as the above-mentioned extreme ultraviolet light output method, which will not be elaborated here.

[0174] Specifically, the computer-readable storage medium 4 may include at least one type of storage medium, for example, it may include flash memory, hard disk, multimedia card, card-type memory, random access memory (RAM), static random access memory (SRAM), programmable read-only memory (PROM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic memory, magnetic disk, optical disc, etc.

[0175] Optionally, the computer-readable storage medium 4 includes a non-volatile computer-readable storage medium, which can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules.

[0176] Specifically, the computer-readable storage medium 4 has a storage space for computer program instructions 41 that execute any method steps in the above method. These program instructions can be read out from or written into one or more computer program products.

[0177] Optionally, the computer program instructions 41 can be compressed in an appropriate form.

[0178] Compared with the prior art, an extreme ultraviolet light output method, device, computer device, and storage medium provided by the present invention have the following advantages:

[0179] 1. The present invention provides an extreme ultraviolet light output method. The output method includes: providing an ionizable medium to a working cavity, providing a first energy to the ionizable medium to pre-ionize it, and generating a first plasma cluster; detecting the temperature in the working cavity at a preset frequency, and obtaining the growth rate of the temperature at the current moment compared with the previous moment; when the growth rate is greater than or equal to a preset value, providing a second energy, and at least completely ionizing the first plasma cluster by the second energy to generate a second plasma cluster, so as to generate and output an extreme ultraviolet beam.

[0180] Understandably, the initial temperature in the working cavity is determined by the ambient temperature in the cavity. When the ambient temperature rises rapidly, it indicates that the pre-ionization process is occurring. By detecting the temperature in the working cavity, it is possible to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for complete ionization to be executed.

[0181] It should be noted that there is an uncontrollable delay time between the pre-ionization and the complete ionization processes. If the delay time is too long, the pre-ionized plasma will recombine. Therefore, this time will affect the conversion efficiency (CE for short) of extreme ultraviolet light radiation. Among them, an infrared detector can be specifically used to detect the temperature in the working cavity.

[0182] The technical solution of the present invention controls the action time of the energy by observing the pre-ionization. In this way, the formed extreme ultraviolet light has higher brightness and stronger stability, and is a better mask detection light source.

[0183] 2. The extreme ultraviolet light output method provided by the embodiment of the present invention. The working cavity is a part of an electrodeless pinch system, and provides a first energy for the ionizable medium to pre-ionize it, including: providing a first energy in the electrodeless pinch system, intercepting part of the first energy to generate a leakage current, and the leakage current pre-ionizes the ionizable medium, and at least part of the ionizable medium is ionized to generate a first plasma cluster.

[0184] As a preferred solution of the embodiment of the present invention, the above first energy is a preset electrical pulse. Understandably, the preset electrical pulse acts on the ionizable medium, causing the ionizable medium to execute the pre-ionization process. The pre-ionization process is specifically to obtain a first plasma cluster by changing the state of the ionizable medium. This process is to prepare for the subsequent complete ionization of the first plasma cluster to obtain a second plasma cluster with a higher valence state. It should be noted that compared with the solution without pre-ionization, the actual CE value of the technical solution of the present invention is higher.

[0185] 3. The extreme ultraviolet light output method provided by the embodiment of the present invention. At least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including: applying the second energy to the position where the first plasma cluster is located; pausing the interception of the first energy within a preset delay time; and completely ionizing the first plasma cluster under the combined action of the first energy and the second energy to generate a second plasma cluster to generate an extreme ultraviolet light beam.

[0186] As one of the preferred embodiments of the present invention, the above-mentioned first energy is a preset electric pulse, and the second energy is a preset pulsed laser. It can be understood that the role of the preset pulsed laser is to act on the first plasma cluster together with the preset electric pulse whose interception is removed. The first plasma cluster is the plasma in a low valence state, so that its size is further pinched. Compared with compressing the plasma by using only the laser or the electric pulse alone, the energy required for this solution is lower and it is easier to implement technically. The purpose of adding the pulsed laser is to utilize the radiation pressure (i.e., light pressure) of the laser to interact with the plasma and improve the output power of extreme ultraviolet light.

[0187] 4. The extreme ultraviolet light output method provided by the embodiment of the present invention, at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, including: within a preset delay time, pausing the interception of the first energy to form the second energy, or maintaining the interception of the first energy and applying the second energy to the position where the first plasma cluster is located; under the action of the second energy, completely ionize the first plasma cluster to generate a second plasma cluster to generate an extreme ultraviolet light beam.

[0188] As one of the preferred embodiments of the present invention, the above-mentioned first energy and second energy are both preset electric pulses. It can be understood that pausing the interception of the first energy to form the second energy, and maintaining the interception of the first energy and applying the second energy to the position where the first plasma cluster is located. Among them, the former only applies a preset electric pulse once during the pre-ionization process, while the latter maintains the interception of the preset electric pulse during the pre-ionization process and applies a second preset electric pulse without interception before the complete ionization process.

[0189] This solution uses a preset electric pulse to change the state of the plasma, reduces the number of times of plasma recombination while improving the conversion efficiency of the extreme ultraviolet light beam. Compared with the solution that only uses the laser alone, this solution is easier to implement technically, does not require an external system for generating pulsed lasers, and is convenient for system integration; compared with the solution of directly applying a preset electric pulse without interception, this solution can reduce the cost of generating and outputting the extreme ultraviolet light beam.

[0190] 5. The extreme ultraviolet light output method provided by the embodiment of the present invention, after at least the second energy completely ionizes the first plasma cluster to generate a second plasma cluster, further includes: obtaining the light field information when the second plasma cluster is generated; performing light field transfer processing and signal processing on the light field information to obtain image information; obtaining the radius or diameter of the second plasma cluster based on the image information.

[0191] Understandably, the technical solution of the present invention first obtains the optical field information when the first plasma cluster is fully ionized to generate the second plasma cluster, and then performs optical field transfer processing and signal processing on the optical field information to obtain image information, so as to obtain the radius or diameter size of the plasma cluster by using imaging detection means during the full ionization process, so as to perform iterative optimization of the system subsequently.

[0192] 6. The embodiment of the present invention also provides an extreme ultraviolet light output device for implementing the above-mentioned extreme ultraviolet light output method. The output device includes: a working cavity for generating an extreme ultraviolet beam; a detection unit for detecting the temperature in the working cavity at a preset frequency to obtain the growth rate of the temperature at the current moment compared with the previous moment; an energy supply unit for providing the first energy and / or the second energy; and a beam output assembly correspondingly arranged at the output end of the working cavity, and the beam output assembly is used to output the extreme ultraviolet beam generated by the working cavity.

[0193] Understandably, the working cavity and the beam output assembly correspondingly arranged at the output end of the working cavity are respectively responsible for generating and outputting the extreme ultraviolet beam, and the detection unit is responsible for detecting the temperature in the working cavity at a preset frequency to determine whether the first energy causes the pre-ionization process of the ionizable medium, so as to control the time for performing full ionization, while the energy supply unit is responsible for providing energy to perform the pre-ionization and / or full ionization process in the working cavity.

[0194] 7. For the extreme ultraviolet light output device provided by the embodiment of the present invention, the working cavity is an electrodeless pinch system, and the temperature detection component includes an infrared thermal imager correspondingly arranged for the electrodeless pinch system; the temperature measurement range of the infrared thermal imager is -20°C to 2000°C, and the thermal sensitivity rate is 30 mK to 80 mK.

[0195] Understandably, the function of the infrared thermal imager is to detect the temperature of the plasma after pre-ionization occurs in the electrodeless pinch system, that is, to detect the temperature inside the electrodeless pinch system, and convert the temperature signal into an image that can be visually distinguished by humans, and the temperature value is calculated by the corresponding software provided by the infrared thermal imager. An increase in temperature indicates that the pre-ionization process is ongoing in the electrodeless pinch system.

[0196] It should be noted that the specific types of the infrared thermal imager include but are not limited to portable infrared thermal imagers, digital thermal imagers, and online infrared thermal imagers, as long as their temperature measurement ranges and thermal sensitivity rates meet the requirements.

[0197] 8. The embodiment of the present invention also provides a computer device, including a memory and a processor. The memory is used to store a computer program, and the processor is used to execute the computer program to implement the above-mentioned extreme ultraviolet light output method.

[0198] This computer device has the same beneficial effects as the extreme ultraviolet light output method described above, and will not be elaborated here.

[0199] 9. The embodiment of the present invention further provides a computer-readable storage medium, on which computer program instructions are stored, and the computer program instructions implement the above extreme ultraviolet light output method when executed by a processor.

[0200] This computer-readable storage medium has the same beneficial effects as the extreme ultraviolet light output method described above, and will not be elaborated here.

[0201] The above has introduced in detail an extreme ultraviolet light output method, device, computer device and storage medium disclosed in the embodiments of the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An extreme ultraviolet light output method, characterized in that, The output method includes: Providing an ionizable medium into the working cavity, providing a first energy to the ionizable medium to pre-ionize it, and generating a first plasma cluster; Detecting the temperature in the working cavity at a preset frequency, and obtaining the growth rate of the temperature at the current moment compared with the previous moment; When the growth rate is greater than or equal to a preset value, providing a second energy, and completely ionizing the first plasma cluster at least by the second energy to generate a second plasma cluster, so as to generate and output an extreme ultraviolet beam.

2. The extreme ultraviolet light output method according to claim 1, wherein The working cavity is a component of an electrodeless pinch system. Providing a first energy to the ionizable medium to pre-ionize it includes: Providing a first energy in the electrodeless pinch system, intercepting part of the first energy to generate a leakage current, and pre-ionizing the ionizable medium by the leakage current, and at least part of the ionizable medium is ionized to generate the first plasma cluster.

3. The extreme ultraviolet light output method according to claim 2, wherein Completely ionizing the first plasma cluster at least by the second energy to generate a second plasma cluster includes: Applying a second energy to the position where the first plasma cluster is located; Pausing the interception of the first energy within a preset delay time; Completely ionizing the first plasma cluster under the combined action of the first energy and the second energy to generate the second plasma cluster, so as to generate the extreme ultraviolet beam.

4. The extreme ultraviolet light output method according to claim 2, wherein Completely ionizing the first plasma cluster at least by the second energy to generate a second plasma cluster includes: Within a preset delay time, pausing the interception of the first energy to form a second energy, or maintaining the interception of the first energy and applying a second energy to the position where the first plasma cluster is located; Completely ionizing the first plasma cluster under the action of the second energy to generate the second plasma cluster, so as to generate the extreme ultraviolet beam.

5. The extreme ultraviolet light output method according to claim 1, wherein, After completely ionizing the first plasma cluster at least by the second energy to generate a second plasma cluster, it further includes: Obtaining the optical field information when the second plasma cluster is generated; Performing optical field transfer processing and signal processing on the optical field information to obtain image information; Obtaining the radius or diameter of the second plasma cluster based on the image information.

6. An extreme ultraviolet light output device for implementing the extreme ultraviolet light output method according to any one of claims 1-5, characterized in that, The output device includes: A working cavity for generating the extreme ultraviolet beam; A detection unit for detecting the temperature in the working cavity at a preset frequency and obtaining the growth rate of the temperature at the current moment compared with the previous moment; An energy supply unit for providing the first energy and / or the second energy; A beam output assembly correspondingly arranged at the output end of the working cavity, and the beam output assembly is used for outputting the extreme ultraviolet beam generated by the working cavity.

7. The extreme ultraviolet light output device according to claim 6, wherein, The working cavity is a component of an electrodeless pinch system, and the temperature detection assembly includes an infrared thermal imager correspondingly arranged for the electrodeless pinch system.

8. The extreme ultraviolet light output device according to claim 7, wherein The temperature measurement range of the infrared thermal imager is from -20°C to 2000°C, and the thermal sensitivity rate is from 30 mK to 80 mK.

9. A computer device, characterized in that, Including a memory and a processor, the memory is used for storing a computer program, and the processor is used for executing the computer program to implement the extreme ultraviolet light output method according to any one of claims 1-5.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, The computer program instructions, when executed by a processor, implement the extreme ultraviolet light output method according to any one of claims 1-5.

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