A desktop high-brightness plasma light source

Abstract

The invention discloses a desktop high-brightness plasma light source, comprising a laser component, a vacuum component, a target material, a magnetic field component for providing a magnetic field area for the target material, and a gas-filled component for supplying gas to the magnetic field area where the target material is located. The target material and the magnetic field component are arranged in the vacuum component. The laser emitted by the laser component irradiates the target material to generate plasma and emit light. The plasma light source can generate a plasma light-emitting area with a more uniform density, thereby greatly increasing the light-emitting efficiency and light-emitting brightness of the laser-driven thermal radiation plasma light source and reducing energy consumption and target fragments.

Description

Technical Field

[0001] The invention relates to the technical field of special light sources, and in particular to a desktop high-brightness plasma light source. Background Art

[0002] Desktop high-brightness light sources have broad application prospects in many fields of basic research and industrial production. However, the typical representative of desktop light sources, X-ray machines, have low brightness and are difficult to cover the deep ultraviolet to soft X-ray bands, which greatly restricts the development of basic science, semiconductor technology and high-end equipment industries. Laser-driven plasma luminescence is an ideal way to develop desktop high-brightness light sources. It generates luminescence by heating the target material with laser to generate high-temperature plasma. It is also called a thermal radiation light source because it mainly ionizes and excites bound electrons to upper energy levels through the hot electron collision process and then generates radiation through the de-excitation process. This laser-driven thermal radiation plasma luminescence light source can cover the deep ultraviolet to soft X-ray band. Compared with synchrotron radiation sources, this laser-driven thermal radiation light source is small in size, low in price, and can be integrated into desktop instruments and equipment. However, there is little research on laser-driven thermal radiation light sources internationally. At present, the main progress is concentrated in two bands: the visible-ultraviolet-deep ultraviolet white light band, the typical application is the deep ultraviolet quantity detection light source in semiconductors; the extreme ultraviolet band, the typical application is the light source of extreme ultraviolet lithography machines. White light sources, also known as deep ultraviolet light sources, are produced by lasers exciting gas targets such as xenon; extreme ultraviolet light sources are currently produced by lasers heating solid or liquid targets such as tin.

[0003] In the process of laser heating solid or liquid target to produce thermal radiation plasma luminescence, the laser cannot directly heat the solid or liquid target material because the target material is opaque to the laser. Only when the target material ablated by the front edge of the laser pulse expands to a gaseous state transparent to the laser, the subsequent laser pulse energy can be efficiently absorbed and heat the target material to the required temperature to produce high-brightness luminescence. Due to the rapid change in the density of the luminescent area, the size of the luminescent area is very small and the laser absorption rate is low, which leads to very low energy conversion efficiency or luminescence efficiency from laser to thermal radiation plasma luminescence.

[0004] In order to improve the luminous efficiency, some target pre-shaping methods have been proposed in the past. A weak pre-pulse laser is used to first shape the initial high-density solid or liquid target into the desired state, and then the main laser pulse heats the shaped target material to produce luminescence. However, the plasma generated by the current target pre-shaping methods is very uneven in space. For example, when a nanosecond laser shapes a droplet target into a flat plate, the plasma generated by the target material after the main pulse laser shaping is very uneven in the laser incident direction; when a picosecond laser shapes a droplet target into a gas state, the plasma is very uneven perpendicular to the laser incident direction. This uneven plasma limits the size of the luminous area and reduces the luminous efficiency, resulting in high energy consumption and high laser power requirements for laser-excited thermal radiation plasma light sources, increasing production costs and limiting application areas. Summary of the invention

[0005] Based on the technical problems existing in the background technology, the present invention proposes a desktop high-brightness plasma light source to produce a plasma light-emitting area with a more uniform density, thereby greatly increasing the luminous efficiency and luminous brightness of the laser-driven thermal radiation plasma light source and reducing energy consumption and target fragments.

[0006] The present invention proposes a desktop high-brightness plasma light source, which includes a laser component, a vacuum component, a target material and a magnetic field component for providing a magnetic field area for the target material. The target material and the magnetic field component are arranged in the vacuum component. The laser emitted by the laser component irradiates the target material to generate plasma and emit light.

[0007] Further, the laser assembly includes a pre-pulse laser and a main pulse laser, and the lasers emitted by the pre-pulse laser and the main pulse laser are irradiated on the target material respectively;

[0008] The pre-pulse laser is used to convert the initial high-density target material such as solid or liquid into a gaseous target material, and the main pulse laser is used to heat the gaseous target material to generate plasma to produce light.

[0009] Further, the magnetic pressure of the magnetic field generated by the magnetic field assembly is equal to the thermal pressure of the cold gaseous target material before being heated by the main pulse laser.

[0010] Further, the magnetic pressure of the magnetic field generated by the magnetic field assembly is equal to the thermal pressure during the heating of the gaseous target material by the main pulse laser.

[0011] Furthermore, the plasma light source also includes a gas filling component for supplying gas to the magnetic field region where the target material is located.

[0012] Furthermore, the gas filling component includes a gas supply device and a gas supply pipe, one end of the gas supply pipe is connected to the output end of the gas supply device, and the other end is inserted into the vacuum component and arranged near the target material.

[0013] Furthermore, in the vacuum component, when the initial high-density target material is ablated by the pre-pulse laser or the main pulse laser and converted into a gaseous state, a high-speed flow will be generated, and the ratio of the initial flow velocity to the Alfvén velocity of the background gas filled in through the inflation component in the magnetic field region is greater than 2, and the high-speed flow will eventually stop moving under the magnetic field constraint provided by the magnetic field component.

[0014] Furthermore, the vacuum component includes a chamber and a vacuum pump for evacuating the chamber, and the target material and the magnetic field component are arranged in the chamber.

[0015] Furthermore, the plasma light source also includes a beam combining mirror and a focusing mirror, and a window glass is arranged on the chamber. The laser emitted by the laser assembly passes through the beam combining mirror and the focusing mirror in sequence and then passes through the window glass to irradiate the target material.

[0016] The advantage of a desktop high-brightness plasma light source provided by the present invention is that: a desktop high-brightness plasma light source provided in the structure of the present invention appropriately constrains the plasma expanded by laser ablation by setting a magnetic field component and an inflation component to form a plasma with a more uniform density, thereby greatly increasing the luminous efficiency and luminous brightness of the laser-driven thermal radiation plasma light source and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a structure in which a magnetic field component is arranged in a vacuum component;

[0018] Figure 2 for Figure 1 The schematic diagram of the structure without the pre-pulse laser;

[0019] Figure 3 A schematic diagram of the structure of arranging a magnetic field component and an inflation component in a vacuum component;

[0020] Figure 4 for Figure 3 The schematic diagram of the structure without the pre-pulse laser;

[0021] Figure 5 In order to add the confinement effect of the magnetic field parallel to the laser direction on the plasma, Figure 5 (a) represents the plasma density profile; (b) represents the outer contour of the confined plasma;

[0022] Figure 6 In order to add a magnetic field parallel to the laser direction and fill the gas to confine the plasma, Figure 6 (a) represents the plasma density profile; (b) represents the outer contour of the confined plasma;

[0023] Among them, 1-laser component, 2-vacuum component, 3-target material, 4-magnetic field component, 5-filling component, 6-beam combining mirror, 7-focusing mirror, 8-plasma, 9-background gas area, 11-pre-pulse laser, 12-main pulse laser, 21-vacuum chamber, 22-vacuum pump, 23-window glass, 24-vacuum gauge. DETAILED DESCRIPTION

[0024] Below, the technical solution of the present invention is described in detail through specific embodiments. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific implementation disclosed below.

[0025] Embodiment 1

[0026] like Figures 1 to 6 As shown, a desktop high-brightness plasma light source proposed by the present invention includes a laser component 1, a vacuum component 2, a target material 3 and a magnetic field component 4 for providing a magnetic field area to the target material 3. The target material 3 and the magnetic field component 4 are arranged in the vacuum component 2. The laser emitted by the laser component 1 irradiates the target material 3 to generate plasma and emit light.

[0027] like Figures 1 to 2 As shown, by setting the magnetic field assembly 4 to form a plasma 8 with a more uniform density, the luminous efficiency and brightness of the laser-driven thermal radiation plasma light source are greatly increased and the energy consumption is reduced.

[0028] Among them, Figures 1 to 2 As shown, the laser component 1 can be a main pulse laser 12, in which case the main pulse laser 12 is used to vaporize and heat the solid / liquid / non-gaseous initial high-density target material 3 to produce light, or it can be a combination of a pre-pulse laser 11 and a main pulse laser 12, in which case the pre-pulse laser 11 is used to convert the target material 3 into a gaseous target material 3, and the main pulse laser 12 is used to heat the gaseous target material 3 to generate plasma to produce light, and the pre-pulse laser 11 can achieve the vaporization of the target material 3 with a relatively low power, which significantly improves the efficiency of the thermal radiation plasma light emission, and improves the energy consumption when only one main pulse laser 12 is used, thereby reducing the energy consumption.

[0029] The above pre-pulse laser 11 or main pulse laser 12 can be replaced with an electron beam with similar power density, but the electron beam generally enters the magnetic field zone parallel to the direction of the magnetic field lines to ablate the target material 3. When the magnetic field strength is weak and the electron beam energy used is high, it can enter the magnetic field zone vertically or at a certain angle to the magnetic field direction to ablate the target material 3.

[0030] This embodiment suppresses the free expansion of the target material 3 by setting a magnetic field, which is applicable to all laser wavelengths or electron beam energies. The magnetic field area should be larger than the plasma luminescence area, and generally should not be less than 1 mm. Considering the convenience of actual use and the difficulty of magnetic field production, the magnetic field area is generally larger than 3 mm. The duration of the magnetic field peak should be longer than the plasma luminescence time. Generally, the plasma luminescence time is approximately equal to the laser pulse width, so the duration of the magnetic field peak should be longer than the laser pulse width.

[0031] In this embodiment, the plasma light source further includes a beam combiner 6 and a focusing lens 7, and a window glass 23 is provided on the vacuum chamber 21. The laser emitted by the laser assembly 1 passes through the beam combiner 6 and the focusing lens 7 in sequence, and then passes through the window glass 23 to irradiate the target material 3. In addition, the vacuum assembly 2 includes a vacuum chamber 21, a vacuum pump 22 for evacuating the vacuum chamber 21, and the target material 3 and the magnetic field assembly 4 are arranged in the vacuum chamber 21. At the same time, a vacuum gauge 24 is provided to detect the vacuum state in the vacuum chamber 21 to ensure that the cavity of the vacuum chamber 21 is always in a relative vacuum state.

[0032] It should be noted that the pre-pulse laser 11 and the main pulse laser 12 can have the same wavelength or different wavelengths, and can be combined by the beam combiner 6 and then focused by a focusing mirror 7 to ablate the target material, or can be focused and ablated separately, and the focusing mirror 7 can be outside the vacuum chamber 21 or inside the vacuum chamber 21. When the pre-pulse laser 11 and the main pulse laser 12 are focused and ablated separately, the laser light emitted by the main pulse laser 12 is reflected by the reflector, and then focused by the focusing mirror to ablate the target material, and the laser light emitted by the main pulse laser 12 is reflected by the reflector, and then focused by the focusing mirror to ablate the target material. At this time, the optical paths of the pre-pulse laser 11 and the main pulse laser 12 are independent.

[0033] A solid or liquid target material 3 is placed in a magnetic field region within a vacuum chamber 21. A pre-pulse laser 11 or an electron beam vaporizes the solid or liquid target material 3. Under the constraint of the magnetic field, the vaporized target material 3 cannot expand freely, and after a period of time evolves into a state with a more uniform density than when it expands freely. Then, the main pulse laser 12 heats the gaseous target material under the constraint of the magnetic field to generate a plasma with a suitable temperature to produce light.

[0034] The specific magnetic field strength is determined by the required luminescence wavelength, and the basic requirement is that the magnetic pressure corresponding to the magnetic field strength is equal to the thermal pressure of the gaseous target. This needs to be divided into two situations: one is that the magnetic pressure of the magnetic field generated by the magnetic field component 4 is equal to the thermal pressure of the cold gaseous target material 3 before the main pulse laser 12 is heated. At this time, the magnetic field only constrains the gaseous target material before the main pulse laser 12 is heated. Although the thermal pressure increases sharply during the heating of the main pulse laser 12, the plasma luminous area will gradually become uneven, but the luminous brightness will be significantly improved compared to the absence of a magnetic field. The advantage of this method is that the magnetic field strength requirement is low, usually between 1T-15T, and the specific value also depends on the required plasma luminescence wavelength and the laser wavelength of the main pulse laser 12; the second is that the magnetic pressure of the magnetic field generated by the magnetic field component 4 is equal to the thermal pressure during the main pulse laser 12 heating the gaseous target material 3. The magnetic field strength required for this method is usually between 5T-100T, and the magnetic field parameter requirements are high, but the advantage is that the plasma luminous area is also difficult to expand during the heating of the gaseous target material by the main pulse laser 12, which can produce higher luminous efficiency and luminous brightness. Which method to use can be adjusted according to the plasma emission wavelength and the main pulse laser wavelength.

[0035] In this embodiment, the magnetic field is set to suppress the free expansion of the target material 3, which is effective for any non-gas target. Strictly speaking, it is suitable for target materials with an average density higher than the laser critical density, which can be solid targets, liquid targets, foam targets, droplet targets, particle targets, spray targets, etc. The magnetic field, laser beam and target surface of the target material can have any angle relationship.

[0036] In addition, the magnetic field component 4 can adopt an electromagnet. The magnetic field strength of a permanent magnet generally cannot meet the requirements. The coil of the electromagnet can be parallel to the target surface, perpendicular to the target surface or at any other angle. The electromagnet is any form of a magnetic field generated by a current-carrying wire, including a solenoid, a single-turn coil, a Helmholtz coil, a single wire, etc.

[0037] In actual use of this embodiment, the magnetic pressure corresponding to the magnetic field strength needs to be close to the thermal pressure of the confined gaseous target material or plasma, for example, the gas density is 2.2×10 20 cm -3 , when the temperature is 5eV, the magnetic field strength must be close to 9T to confine the gas.

[0038] The intensity of the pre-pulse laser 11 or electron beam must be greater than the critical power density of the gaseous target material. For example, for a solid tin target, when a 1 μm laser pre-pulse is used, the laser intensity must be greater than 5×10 8 W / cm 2 , otherwise the target material cannot be vaporized.

[0039] The power density of the main pulse laser 12 or the electron beam focused on the target surface of the target material 3 must be greater than a certain value, otherwise the plasma temperature is too low and the atoms cannot be ionized to the required ionization degree, and the luminous efficiency will be very low; the power density focused on the target surface cannot be too high, otherwise the atoms will be over-ionized and the luminous efficiency will also be reduced. For example, for extreme ultraviolet lithography light sources, the plasma temperature is best at around 30 eV, which requires the laser focus intensity of 1 μm wavelength to be around 1×10 11 W / cm 2 For lasers and plasma luminescence of other wavelengths, the laser intensity should be changed accordingly. This embodiment is effective for visible, ultraviolet, deep ultraviolet white light sources, extreme ultraviolet, XUV, VUV, and soft X-rays in the energy range of 1eV-10keV.

[0040] Advantages of embodiment 1:

[0041] 1. The target material 3 after being vaporized by the pre-pulse laser 11 or electron beam under the constraint of magnetic field cannot expand freely, so the density distribution is more uniform, and the low-temperature plasma that absorbs and emits light in the periphery is eliminated. When heated by the main pulse laser 12, the luminous efficiency and brightness of the plasma can be greatly increased;

[0042] 2. The density of the target material 3 after being vaporized by the pre-pulse laser 11 or electron beam under magnetic field constraint can be precisely controlled. The target material 3 after being vaporized can be adjusted to the optimal parameter state for different plasma emission wavelengths and laser wavelengths, so that the luminescence efficiency closer to the theoretical upper limit can be obtained, and the spectral characteristics of the luminescence can also be actively controlled;

[0043] 3. In addition to constraining the target material 3 vaporized by the pre-pulse laser 11 or the electron beam, the magnetic field also constrains the plasma expansion during the heating period of the main pulse laser 12. Since the light-emitting area cannot expand freely, the plasma luminescence efficiency is higher, and at this time, the requirements for the uniformity of the pre-pulse and main pulse laser spots, the laser pulse width, etc. can be reduced, reducing the requirements for laser technology;

[0044] 4. The target material 3 under the constraint of the magnetic field cannot expand freely, and the consumption of the target material is reduced, so that less target material 3 can be used, the pollution of target fragments is small, and the life of the light source is increased.

[0045] Embodiment 2

[0046] like Figures 1 to 4 As shown, the structure of the second embodiment is basically the same as that of the first embodiment. The main difference is that the second embodiment is provided with an inflation component 5 for supplying gas to the magnetic field region where the target material 3 is located. The purpose of providing the inflation component 5 is mainly described below.

[0047] like Figures 3 to 4As shown, when the gas filling component 5 fills the vacuum chamber 21 with low-density background gas, the gas filling area is only related to the luminescence wavelength and has nothing to do with the laser wavelength. In most cases, low-density gas can be filled near the target material 3 to form a background gas area 9. At this time, the gas filling component 5 includes a gas supply device and a gas supply pipe. One end of the gas supply pipe is connected to the output end of the gas supply device, and the other end is inserted into the vacuum component 2 and arranged near the target material 3. At this time, the gas supply pipe is provided with a nozzle at the end away from the gas supply device. The nozzle can be a pressure-type nozzle. The shape formed by the gas ejected from the nozzle can cover the entire target material area, thereby inhibiting the free expansion of the target material to obtain a uniform plasma. When the gas filled has little absorption of luminescence, the entire target chamber can be filled. When the target chamber is small in size and the path through which the luminescence passes is short, the entire target chamber can also be filled, so that the entire background gas fills the vacuum chamber 21, otherwise it can only be filled near the target material.

[0048] A high-density target material 3 such as a solid or liquid is placed in a magnetic field region in a vacuum chamber 21, and a low-density background gas is filled around the target material 3 through a gas filling assembly 5; the laser emitted by the main pulse laser 12 heats the high-density target material, or the pre-pulse laser 11 or electron beam first vaporizes the high-density target material 3 and then the main pulse laser 12 heats the gaseous target material, generating a high-temperature plasma that radiates light of the required wavelength. The wavelength of the light emission can be adjusted by adjusting the laser parameters and the target parameters. As described in Example 1, the magnetic pressure of the magnetic field needs to be close to the thermal pressure of the plasma, which can be divided into two situations: (1) The magnetic field only constrains the target material vaporized by the pre-pulse before heating by the main pulse laser 12. At this time, the thermal pressure of the gaseous target material is very small and the required magnetic field strength is low; (2) The magnetic field constrains the high-temperature plasma emitted by the main pulse laser 12 during laser heating. At this time, the thermal pressure of the plasma light emission area is large and the required magnetic field strength is high. The specific method to be selected depends on the difficulty of achieving the magnetic field strength determined by the required light emission wavelength, etc.

[0049] What is emphasized in the second embodiment is that when the gaseous target material is ablated by a magnetic field-confined laser, on the one hand, the target material 3 will escape along the direction of the magnetic field lines. On the other hand, even in the direction perpendicular to the magnetic field lines, fluid instability will occur at the interface of the target material constrained by the magnetic field, which will destroy the confinement effect and cause material leakage, destroying the magnetic field confinement effect, resulting in reduced luminous brightness, and the plasma leaking along the magnetic field lines will also produce debris contamination.

[0050] In the second embodiment, the instability and the escape of materials along the magnetic field lines are suppressed by the background gas filled around the target material 3. When the density of the gas filled by the gas filling component 5 is greater than 0.1 times the density of the constrained target material, the instability can be significantly suppressed; in order to suppress the escape of materials along the direction of the magnetic field lines, the gas filling density should be higher. Therefore, in the vacuum component 2 of the second embodiment, when the initial high-density target material 3 is ablated by the pre-pulse laser 11 or the main pulse laser 12 and converted to the gas state, a high-speed flow will be generated. The ratio of the initial flow velocity of the flow to the Alfvén velocity of the background gas filled by the gas filling component 5 in the magnetic field is greater than 2, and the high-speed flow will eventually stop moving under the magnetic field constraint provided by the magnetic field component 4. Because the target material 3 has just been ablated, the flow velocity is very high and the density is too high. The magnetic field cannot be constrained and does not need to be constrained at this time. Only when it expands to a certain volume and the density is as low as the required value can the magnetic field be constrained. The lower density constrained by this magnetic field is the desired ideal state, and the luminous brightness is the highest at this time. When the density is too large, the luminous brightness is low, and of course, when the density is too low, the luminous brightness is also low.

[0051] For different luminous wavelengths, the minimum filling density can be determined based on the above two criteria. The filling density cannot be too high, because the gas filled in will absorb the generated plasma luminescence. The specific requirements depend on the photon energy of the luminescence. For example, when the photon energy is in the extreme ultraviolet region, the gas absorption of luminescence is too strong, and low atomic number hydrogen is needed, and the filling density just exceeds the minimum density given by the above criteria; if it is soft X-ray, the gas absorption of luminescence is weak, the filling density can be slightly higher, and helium with a slightly higher atomic number can also be used. In addition, the luminescence outlet cannot be too far from the luminescence point, that is, the distance between the luminescence and the gasified area should not be too large, so as to reduce the absorption of luminescence by the filling.

[0052] In the second embodiment, it is not excluded that the plasma light source includes the laser component 1, the vacuum component 2, the target material 3 and the gas-filled component 5. In this case, the magnetic field component 4 is not provided in the plasma light source, and the gas-filled component 5 can also achieve the effect of suppressing the free expansion of the target material 3, thereby obtaining a uniform plasma. However, in the second embodiment, the plasma light source includes the laser component 1, the vacuum component 2, the target material 3, the magnetic field component 4 and the gas-filled component 5, which is a better solution, and can better achieve the effect of suppressing the free expansion of the target material 3, thereby obtaining a uniform plasma.

[0053] The beneficial results of the second embodiment are:

[0054] 1. When a rarefied background gas is filled, the magnetic field constrains the target material ablated by the laser, and the density of the luminous area is uniform, the size is larger and controllable. Even over a long period of time, the target material will not leak due to instability, and the luminous brightness can be greatly increased;

[0055] 2. When a rarefied background gas is filled, the target material ablated by the magnetic field-constrained laser is better constrained and does not leak, which reduces the self-absorption of the target material 3 outside the luminous area and can improve the luminous brightness.

[0056] 3. When a rarefied background gas is filled, the target material ablated by the magnetic field-constrained laser will not leak along the magnetic field lines or perpendicular to the magnetic field lines, which greatly reduces the pollution of target fragments and increases the life of the light source;

[0057] 4. When a rarefied background gas is filled, the effect of the target material ablated by the magnetic field confinement laser is less sensitive to the direction of the magnetic field, so there is no strict requirement for the direction of the magnetic field relative to the target material 3, and the technical implementation is more convenient;

[0058] 5. When a rarefied background gas is filled, the target material ablated by the magnetic field-constrained laser is better constrained, which reduces the technical requirements for laser parameters such as focusing uniformity, time waveform flatness, and target parameters such as surface finish.

[0059] It should be noted that if Figures 1 to 4 As shown, for the laser component 1 in Example 1 and Example 2, the laser in the laser component 1 can have only one main pulse laser 12, or can be a combination of a pre-pulse laser 11 and a main pulse laser 12. When combined, the optical paths of the pre-pulse laser 11 and the main pulse laser 12 can share the beam combining lens 6 and the focusing lens 7, or independent optical paths can be set.

[0060] In summary, the following results are obtained by testing Example 1 and Example 2: Figure 5 and 6 As shown in the figure, Figure 5 It means that the magnetic field component 4 is added only near the target material 3 to generate a magnetic field, so that the target material 3 is under the magnetic field constraint. The upper and lower parts are the magnetic field direction and the laser direction. The lowermost part is the initial solid target material position. Figure 6 It means that the target material 3 is placed under the magnetic field and gas constraints after the magnetic field assembly 4 is added and the gas is filled. The top and bottom are the magnetic field direction and the laser direction, and the bottom is the initial solid target material position. Figure 5 In the figure, it can be seen that the plasma is constrained and cannot expand freely, but there is a small amount of plasma leakage along the magnetic field lines on the upper side. The surface of the constrained plasma has wrinkled fluid instability, which will also cause plasma leakage over a long period of time. Figure 6 In the figure, it can be seen that the plasma is constrained and cannot expand freely, and the plasma leakage along the magnetic field lines on the upper side is suppressed. The wrinkled fluid instability on the plasma surface is also significantly weakened, and the plasma leakage perpendicular to the magnetic field lines is also suppressed, and the plasma is better constrained.

[0061] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A desktop high brightness plasma light source, characterized in that: The invention comprises a laser component (1), a vacuum component (2), a target material (3), and a magnetic field component (4) for providing a magnetic field region for the target material (3); the target material (3) and the magnetic field component (4) are arranged in the vacuum component (2); the laser light emitted by the laser component (1) irradiates the target material (3) to generate plasma and emit light; The laser assembly (1) comprises a pre-pulse laser (11) and a main pulse laser (12), and the lasers emitted by the pre-pulse laser (11) and the main pulse laser (12) are respectively irradiated on the target material (3); The pre-pulse laser (11) is used to convert the initial high-density target material (3) into a gaseous target material, and the main pulse laser (12) is used to heat the gaseous target material (3) to generate plasma to generate light. The magnetic pressure of the magnetic field generated by the magnetic field assembly (4) is equal to the thermal pressure of the cold gaseous target material (3) before being heated by the main pulse laser (12); or, The magnetic pressure of the magnetic field generated by the magnetic field assembly (4) is equal to the thermal pressure during the heating of the gaseous target material (3) by the main pulse laser (12).

2. The desktop high brightness plasma light source according to claim 1, characterized in that: The plasma light source also includes a gas filling component (5) for supplying gas to the magnetic field region where the target material (3) is located.

3. The desktop high brightness plasma light source according to claim 2, characterized in that: The gas filling component (5) comprises a gas supply device and a gas supply pipe, one end of the gas supply pipe is connected to the output end of the gas supply device, and the other end is inserted into the vacuum component (2) and arranged near the target substance (3).

4. The desktop high brightness plasma light source according to claim 2, characterized in that: In the vacuum component (2), when the initial high-density target material (3) is ablated by the pre-pulse laser (11) or the main pulse laser (12) and converted into a gaseous state, a high-speed flow is generated, and the ratio of the initial flow velocity to the Alfvén velocity of the background gas filled in through the filling component (5) in the magnetic field region is greater than 2, and the high-speed flow will eventually stop moving under the magnetic field constraint provided by the magnetic field component (4).

5. The desktop high brightness plasma light source according to claim 1, characterized in that: The vacuum component (2) comprises a vacuum chamber (21) and a vacuum pump (22) for evacuating the vacuum chamber (21); the target material (3) and the magnetic field component (4) are arranged in the vacuum chamber (21).

6. The desktop high brightness plasma light source according to claim 5, characterized in that: The plasma light source also includes a beam combining mirror (6) and a focusing mirror (7). A window glass (23) is provided on the vacuum chamber (21). The laser light emitted by the laser assembly (1) passes through the beam combining mirror (6) and the focusing mirror (7) in sequence and then passes through the window glass (23) to irradiate the target material (3).

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