Method and device for inhibiting negative hydrogen ion source from leading out electrons and maintaining uniformity

Abstract

The invention discloses a method and device for inhibiting a negative hydrogen ion source from leading out electrons and maintaining uniformity, and relates to the technical field of magnetic confinement fusion, and the method comprises the steps: building a discharge chamber of a radio frequency dual-drive ion source comprising a drive source region, a diffusion region and a grounding shielding cover, and enabling the drive source region to be in sealed connection with the diffusion region, a back plate is made of stainless steel, the side wall is a quartz cylinder wound with a radio frequency copper wire coil, and a partition plate or a grid mesh is arranged near an outlet of the driving source area; discharging gas is introduced into the cavity, power is applied to the coil to generate plasma, and electrons are absorbed through the partition plate or the grid mesh to achieve the suppression effect. The method does not need to depend on a filtering magnetic field, E * B-and anti-magnetic drift interference can be avoided, damage of electrons to H-ions is effectively reduced, grid thermal load is reduced, plasma uniformity can be maintained, the density ratio of the electrons to negative hydrogen ions is optimized, and beam quality and transmission efficiency are remarkably improved.

Description

Technical Field

[0001] This application relates to the field of magnetic confinement fusion technology, and in particular to a method and apparatus for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity. Background Technology

[0002] Neutral beam injection (NBI) heating is the most competitive auxiliary heating method in fusion reactors. Its core principle is to heat the plasma to ignition temperature using a high-energy neutral beam. This high-energy neutral beam is obtained by neutralizing a high-energy ion beam, and the negative hydrogen ion source is the key component for generating this high-energy ion beam. In a radio frequency negative hydrogen ion source (RF NHIS), the co-extraction of electrons destroys H... - Ions increase the thermal load on the extraction gate. Existing methods for suppressing these electrons rely on filtering magnetic fields, but filtering magnetic fields can cause E×B- drift and antimagnetic drift, resulting in plasma inhomogeneity and reduced beam quality and transmission efficiency. Summary of the Invention

[0003] The purpose of this application is to provide a method and apparatus for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity, which can solve the technical problem of plasma inhomogeneity caused by relying on a filtering magnetic field in the prior art, and achieve synergistic optimization of suppressing the extraction of electrons and maintaining plasma uniformity.

[0004] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a method for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity, comprising the following steps: A discharge chamber equipped with a dual-drive ion source for radio frequency is constructed, and a partition or grid is installed near the outlet of the drive source area. The discharge chamber includes a drive source area, a diffusion area, and a grounded shield. The drive source area and the diffusion area are sealed together, and the shield is installed on the outside of the drive source area. The back plate of the drive source area is made of stainless steel, and the side wall is a quartz cylinder. Radio frequency copper wire coils are wound around the outside of the quartz cylinder.

[0005] Discharge gas is introduced into the discharge chamber, and power is applied to the radio frequency copper wire coil in the driving source region to generate plasma in the discharge chamber.

[0006] By absorbing electrons through partitions or grids, the common extracted electrons can be suppressed while maintaining plasma homogeneity.

[0007] Optionally, the driving source area includes a stainless steel backplate and a quartz tube sidewall, with a 5-turn RF copper wire coil wound around the outside of the quartz tube. The driving source area has a height of 14cm, a diameter of 28cm, a coil diameter of 29cm, and an RF frequency of 2MHz. The driving source area includes two driving sources with a center-to-center distance of 44cm between them.

[0008] Optionally, the sidewall material of the diffusion zone is 304 stainless steel, and the diffusion zone is 100cm long, 50cm wide, and 25cm high; the driving source zone and the diffusion zone are sealed and connected by fluororubber O-rings.

[0009] Optionally, the material of the partition or grid is nickel-plated copper, tungsten or molybdenum; when nickel-plated copper is used, the thermal conductivity of copper is used to achieve rapid heat transfer, and the resistance of the nickel plating to plasma erosion and sputtering is used to protect the substrate.

[0010] Optionally, there are 10 partitions, with dimensions of 0.5cm, 50cm, and 5cm in the x, y, and z directions, respectively. The partitions are located at the boundary between the driving source region and the diffusion region.

[0011] Optionally, there are two grids, which are respectively set at the outlets of the two drive sources. The outer dimensions of each grid are 28cm×50cm, and the grid has 3 mesh openings, each mesh opening being 4cm×50cm in size.

[0012] Optionally, the method further includes: adjusting the position of the partition or grid along the z-axis; and / or applying a DC bias voltage to the partition or grid to attract electrons to accelerate and impact the partition or grid and dissipate them.

[0013] Secondly, this application provides a device for suppressing electron extraction from a negative hydrogen ion source and maintaining uniformity, comprising: a discharge chamber with a radio frequency dual-drive ion source, a partition or a grid; the discharge chamber includes a drive source region, a diffusion region, and a grounded shield; the back plate of the drive source region is made of stainless steel, and the side wall is a quartz cylinder, with a radio frequency copper wire coil wound around the outside of the quartz cylinder; the diffusion region is sealed to the drive source region; the shield is installed outside the drive source region to prevent electromagnetic interference from radio frequency signals to measuring instruments; the partition or grid is disposed near the outlet of the drive source region to absorb electrons to suppress common electron extraction and maintain plasma uniformity.

[0014] Optionally, the driving source area has a height of 14cm and a diameter of 28cm, the RF copper wire coil has 5 turns and a diameter of 29cm, the driving source area includes two driving sources with a center-to-center distance of 44cm, and the RF frequency is 2MHz; the sidewall of the diffusion area is made of 304 stainless steel, the diffusion area is 100cm long, 50cm wide, and 25cm high; the diffusion area and the driving source area are sealed together by fluororubber O-rings.

[0015] Optionally, the material of the partition or grid is nickel-plated copper, tungsten, or molybdenum; the number of partitions is 10, with dimensions of 0.5cm, 50cm, and 5cm in the x, y, and z directions, respectively, and they are located at the boundary between the driving source region and the diffusion region; the number of grids is 2, with an outer dimension of 28cm × 50cm, and three 4cm × 50cm mesh openings, respectively located at the outlets of the two driving sources; the position of the partitions or grids can be adjusted along the z-axis, and a DC bias voltage can be applied.

[0016] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides a method and apparatus for suppressing electron extraction from a negative hydrogen ion source and maintaining uniformity. In this method, the sealed connection between the driving source region and the diffusion region maintains a vacuum environment in the chamber, providing the necessary conditions for plasma generation and stable existence. A partition or grid placed near the outlet of the driving source region can directly act on the electron transport path. Compared to traditional filtering magnetic fields, this can fundamentally avoid the interference of E×B- drift and antimagnetic drift on the plasma, thereby preventing the extraction of H+ ions. - The increased divergence angle of the ion beam ensures beam quality and transmission efficiency. By introducing discharge gas into the discharge chamber and applying power to the radio frequency copper wire coil in the driving source region, this excitation method efficiently generates plasma. Furthermore, the radio frequency dual-drive structure further enhances the stability and initial density uniformity of plasma generation, laying the foundation for subsequent H... - This lays the foundation for ion generation and efficient extraction; by absorbing electrons through septa or grids, the common extraction of electrons is suppressed, and this absorption method can effectively prevent electrons from interacting with H+. - The ion dissociation reaction significantly improves the negative ion extraction efficiency, while preventing high-energy electrons from impacting the extraction grid and generating excessive heat, thus reducing the thermal load on the extraction grid. Furthermore, this method does not rely on a filtering magnetic field, achieving efficient electron suppression while maintaining good plasma homogeneity and optimizing electron density and H2O. - The ratio of ion density further enhances the overall performance of the negative hydrogen ion source. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1This is a flowchart illustrating a method for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity, as provided in an embodiment of this application.

[0019] Figure 2 This is a schematic diagram of a device for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity, provided in an embodiment of this application.

[0020] Figure 3 This is a schematic diagram of the structure of the discharge chamber in another embodiment of this application, where a permanent magnet is used to generate a filtering magnetic field and a baffle or grid is set near the outlet of the driving source region to suppress the common extraction of electrons.

[0021] Figure 4 In another embodiment of this application, electron density is achieved using three methods to suppress electron extraction. Negative hydrogen ion density Electronic temperature Plasma potential and hydrogen atom density distribution A schematic diagram of the distribution.

[0022] Figure 5 In another embodiment of this application, the electron density and negative hydrogen ion density are obtained using three methods to suppress electron extraction. / A schematic diagram of the ratio curve. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] The principle of neutral beam injection heating is to inject a high-energy neutral beam into the tokamak device. During collisions with charged particles, the neutral beam transfers kinetic energy to the plasma, thus heating it to its ignition temperature. High-energy neutral beams are obtained by neutralizing a high-energy ion beam. Therefore, the ion source device that generates the high-energy ion beam is the core front-end component of the NBI system. Although both positive and negative ion beams can be converted into neutral beams through a neutralization process, the neutralization efficiency of positive ions drops sharply when the energy exceeds 100 eV / amu, while the neutralization efficiency of negative ions can remain around 60%. Furthermore, compared to filament ion sources, radio frequency ion sources offer simplicity in mechanical and electrical design and are suitable for long-pulse discharges. Therefore, NBI systems based on radio frequency negative hydrogen ion sources are an inevitable choice for large-scale magnetic confinement fusion reactors such as ITER.

[0025] A key challenge of radio frequency negative hydrogen ion sources is suppressing co-extracted electrons: on the one hand, electrons will react with H+. - The ions undergo a dissociation reaction, thus destroying the H+. - Ions reduce the extraction efficiency of negative ions; on the other hand, electrons accelerated to high energies collide with the extraction grid surface, instantly converting their enormous kinetic energy into heat energy, increasing the thermal load on the extraction grid. Existing methods to suppress extracted electrons mainly include adding a filtering magnetic field, bias voltage, and deflecting magnets. Among these, adding a filtering magnetic field (between the ion source generation region and the extraction region) is efficient and widely used, but under the influence of E×B- and diamagnetic drift, it can cause plasma inhomogeneity, thus leading to reduced extraction efficiency of H+. - An increased ion beam divergence angle leads to decreased quality and reduced transmission efficiency. Applying a bias voltage (at the first-layer gate) can only deflect low-energy electrons because excessively high bias voltages suppress H electrons. - Since ion extraction is involved, this method still needs to be used in conjunction with a filtering magnetic field. Adding a deflecting magnet (embedded in the extraction electrode) is a suppression measure taken after electrons have already been extracted, at which point some of the electrons would otherwise be used to accelerate H+. - The energy of the ions may lead to the eventual extraction of H. - The ion beam intensity is insufficient. Therefore, the extracted electron processing still needs to be combined with the electron suppression method (i.e., the filtering magnetic field method) inside the ion source to form a complete electron suppression scheme. In general, the above methods all rely on the synergistic use of the filtering magnetic field, and the biggest drawback of the filtering magnetic field method is that it causes plasma inhomogeneity.

[0026] This application aims to propose a method of adding septa or grids to replace filtering magnetic fields, thereby suppressing electron extraction while ensuring plasma homogeneity. Furthermore, homogeneity and electron density can be further altered by adjusting parameters such as the structure, position, and bias voltage of the septa / grid. With H - Ion density The values ​​ultimately yielded uniformity and / A well-proportioned structure is of great significance for improving the quality and intensity of the beam.

[0027] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] This application provides a method for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity. In one exemplary embodiment, such as... Figure 1 As shown, it includes the following steps: A1. Construct a discharge chamber equipped with a dual-drive ion source for radio frequency, and install a partition or grid near the outlet of the drive source area; the discharge chamber includes a drive source area, a diffusion area and a grounded shield, the drive source area and the diffusion area are sealed together, and the shield is installed on the outside of the drive source area; the back plate of the drive source area is made of stainless steel, the side wall is a quartz cylinder, and an radio frequency copper wire coil is wound on the outside of the quartz cylinder.

[0029] A2. Discharge gas is introduced into the discharge chamber, and power is applied to the radio frequency copper wire coil in the driving source region to generate plasma in the discharge chamber.

[0030] A3. By absorbing electrons through partitions or grids, the common extracted electrons are suppressed, while maintaining plasma homogeneity.

[0031] Based on the same inventive concept, this application also provides a device for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity. The solution provided by this device is similar to the solution described in the above-described method. In an exemplary embodiment, such as... Figure 2 As shown, a device is provided to suppress the extraction of electrons from a negative hydrogen ion source and maintain uniformity, comprising: a discharge chamber with a radio frequency dual-drive ion source, a partition or a grid.

[0032] The discharge chamber includes a driving source region, a diffusion region, and a grounded shield. The back plate of the driving source region is made of stainless steel, and the side wall is a quartz cylinder. An RF copper wire coil is wound around the outside of the quartz cylinder. The diffusion region is sealed to the driving source region. The shield is installed outside the driving source region to prevent RF signals from causing electromagnetic interference to the measuring instruments. The partition or grid is located near the outlet of the driving source region to absorb electrons to suppress common electron extraction and maintain plasma homogeneity.

[0033] In one exemplary embodiment, the driving source region includes a stainless steel backplate and a quartz tube sidewall, with a 5-turn RF copper wire coil wound around the outside of the quartz tube, such as... Figure 2 As shown, the driver source area has a height of 14cm and a diameter of 28cm, the coil diameter is 29cm, and the radio frequency is 2MHz; the driver source area includes two driver sources, with a center-to-center distance of 44cm between the two driver sources. Figure 2 In the middle, the two driving sources on the left and right are labeled as driving source I and driving source II, respectively.

[0034] In one optional embodiment, the sidewall material of the diffusion region is 304 stainless steel, and the diffusion region is 100cm long, 50cm wide and 25cm high. The driving source region and the diffusion region are sealed and connected by a fluororubber O-ring. The driving source region and the diffusion region together constitute a vacuum discharge chamber. After hydrogen discharge gas is introduced into the vacuum chamber, power is applied to the coil, and plasma will be generated between the vacuum chambers.

[0035] In this embodiment, the material of the partition or grid near the outlet of the driving source region is nickel-plated copper, tungsten, or molybdenum. When nickel-plated copper is used, the thermal conductivity of copper is used to achieve rapid heat transfer, and the plasma erosion resistance and sputtering resistance of the nickel plating layer are used to protect the substrate.

[0036] Specifically, the partitions and / or grids should have good thermal conductivity and surface hardness, and nickel-plated copper is a material that achieves an excellent balance between performance, cost, and machinability. Copper has excellent thermal conductivity, which helps components quickly dissipate heat, preventing localized overheating, thermal deformation, or even melting, as a large amount of heat is generated within the vacuum chamber. The nickel plating provides resistance to plasma erosion and sputtering. Pure copper has a relatively soft surface and is easily sputtered and etched by high-energy particles, generating contaminant particles and shortening component life. Nickel plating offers significantly better hardness and sputtering resistance than copper, providing a crucial protective layer and reducing contamination.

[0037] It is worth noting that since the partition and / or grid itself are made of materials with excellent conductivity such as nickel-plated copper, tungsten, or molybdenum, they have the ability to directly bear and conduct bias voltage. In this embodiment, there is no need to add an additional "bias plate" as an intermediate transition component. By using conventional conductive connectors (such as conductive brackets, terminals, metal connectors, etc., the bias voltage transmission function can be equivalently carried), the power output terminal can be directly or indirectly connected to the partition / grid to form a stable bias voltage circuit. This prevents the electrons absorbed by the partition and / or grid from accumulating on the surface of the component and forming electron enrichment. At the same time, it can also achieve precise application of bias voltage, which simplifies the structural design, reduces the assembly complexity, and does not affect the bias voltage adjustment effect.

[0038] In another exemplary embodiment of this application, the method provided in the above embodiments further includes: adjusting the structure or position of the partition or grid along the z-axis direction; and / or applying a DC bias voltage to the partition or grid to attract electrons to accelerate and impact the partition or grid and cause them to dissipate.

[0039] Specifically, structurally, the number, size (height and thickness), and spacing of the partitions, as well as the number and size of the grid apertures, can be altered. This affects plasma transport, thereby further optimizing plasma uniformity and... / Positionally, the septum / grid can be moved along the z-axis. Preliminary results indicate that moving it too close to the extraction region leads to poor plasma homogeneity and... / From a bias perspective, a DC bias can be added to the separator / grid to attract more electrons, accelerate them to the separator / grid, and thus improve their efficiency. / .

[0040] Next, a comparative example using a permanent magnet to generate a filtering magnetic field will be used to highlight the beneficial effects of the proposed solution of placing a baffle / grid near the outlet of the drive source region. For example... Figure 3 As shown, the use of permanent magnets to generate filtering magnetic fields (such as...) are illustrated. Figure 3 As shown in part (a), a baffle is installed near the outlet of the drive source area (such as...). Figure 3 As shown in part (b), a grid is installed near the outlet of the drive source area (such as...). Figure 3 The chamber structure shown in part (c) suppresses the co-extraction of electrons.

[0041] exist Figure 3 In part (a), the dimensions of a single permanent magnet in the x, y, and z directions are 9 cm, 5 cm, and 2 cm, respectively, with a remanence of 1.5 T. They are uniformly distributed on both sides of the bottom of the diffusion region, with a distance of 5 cm between two magnets, generating a magnetic field along the +y direction inside the cavity.

[0042] exist Figure 3 In part (b), there are 10 partitions made of nickel-plated copper, and these 10 partitions are placed at the boundary between the source region and the diffusion region. The dimensions of the partitions in the x, y, and z directions are 0.5 cm, 50 cm, and 5 cm, respectively.

[0043] exist Figure 3 In part (c), there are two grids, the grid material is nickel-plated copper, the two grids are respectively set at the outlet of the two drive sources, the outer dimensions of each grid are 28cm×50cm, the grid has 3 mesh openings, and the size of each mesh opening is 4cm×50cm.

[0044] Furthermore, the discharge chamber structure and size defined in the above embodiments are exemplary examples. In practical applications, the discharge chamber can be changed to any size as needed to meet different application requirements.

[0045] To visually compare the electron suppression and plasma homogeneity optimization effects of the three modules, a two-dimensional fluid simulation was performed on the xz plane (y=25cm) of the aforementioned geometry using the plasma module, electromagnetic field module, and static magnetic field module. Under appropriate boundary conditions, the spatial distribution of plasma parameters can be obtained through the coupling of these three modules. The plasma module is used to solve the fluid equations for electrons, ions, and neutral particles within the source and diffusion regions, obtaining the density, flux, and energy of each particle. The electromagnetic field module is used to solve for the electrostatic and induced electromagnetic fields throughout the simulation domain, while the static magnetic field module is used to solve for the distribution of the filtering magnetic field generated by the permanent magnet throughout the simulation domain.

[0046] Figure 4 Electron density was compared under three methods of suppressing electron extraction. Negative hydrogen ion density Electronic temperature Plasma potential and hydrogen atom density distribution . Figure 4 The first column uses a traditional magnetic field filtering method, the second column uses a method with added partitions, and the third column uses a method with added grids. Figure 4 of( a ) part ~( c The comparison of the two methods shows that the permanent magnet method has the highest electron density in the source region. This is because the permanent magnet reduces electron extraction by hindering plasma transport to the diffusion region, while the other two methods reduce electron extraction by absorbing electrons. The electron density values ​​at the bottom of the diffusion region are similar for both the permanent magnet and separator methods, indicating that the separator's effect on suppressing electron extraction is comparable to that of the permanent magnet, both effectively suppressing electron extraction. The electron density at the bottom of the diffusion region is slightly higher in the grid method than the other two methods, resulting in a slightly lower suppression effect; however, this method still has a suppressive effect on electrons. Figure 4 of( d ) part ~( f The comparison of the two sections shows that the symmetrical and uniform distribution of negative hydrogen ion density is very poor under the permanent magnet method, while it is better under the partition and grid method. The negative hydrogen ion density is the highest under the grid method, because more higher-energy electrons are transported to the diffusion region, promoting the dissociation of hydrogen molecules into hydrogen atoms (by...). Figure 4 of( g ) part ~( i ) part and Figure 4 of( m ) part ~( o (As shown in the section), and hydrogen atoms are the key reactants generated on the surface of negative hydrogen ions. Furthermore, negative hydrogen ions are more easily transported to the driving source region under magnetic field conditions because the plasma potential in the source region is higher in this mode ( Figure 4 of( j ) part ~( l (Partially), negative hydrogen ions are transported upward under the influence of a bipolar electric field.

[0047] In another exemplary embodiment of this application, a cut-off line within 7 cm of the lead-out area on the axis of the driving source region is taken (e.g., Figure 3 (The red cutoff line in section (a)) compares the electron density with the negative hydrogen ion density under three methods of suppressing electron extraction. / The ratio, the lower the value, the better the performance of the driver source; generally, it should be <1 near the pinout area. The results are as follows... Figure 5 As shown, the farther away from the extraction area, the better. / The larger the value, the better. (Under the partition method) / The lowest, the highest with the grid configuration. Within a 2cm range closer to the lead-out area, all three... / The values ​​are similar, both less than 1.

[0048] This application provides a method for suppressing electron extraction from a negative hydrogen ion source while maintaining uniformity. Addressing the problem that existing filtering magnetic fields easily induce plasma inhomogeneity and reduce beam quality when suppressing co-extraction of electrons, this method constructs a radio frequency dual-drive ion source discharge chamber containing a driving source region, a diffusion region, and a grounded shield. The driving source region and the diffusion region are sealed together. The backplate is made of stainless steel, and the sidewalls are quartz cylinders with wound radio frequency copper wire coils. A partition or grid is placed near the outlet of the driving source region. Discharge gas is introduced into the chamber, and power is applied to the coils to generate plasma. Electrons are absorbed by the partition or grid, achieving the suppression effect. This method does not rely on a filtering magnetic field, avoids E×B- interference and anti-magnetic drift interference, and effectively reduces electron interference to H. - The destruction of ions reduces the thermal load on the grid while maintaining plasma homogeneity and optimizing the ratio of electron to negative hydrogen ion density, significantly improving beam quality and transmission efficiency. It is suitable for NBI systems in large fusion reactors such as ITER.

[0049] certainly, Figures 2-3 The architecture shown is merely exemplary; it can be omitted as needed when implementing different functionalities. Figures 2-3 One or at least two components of the system shown.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method of suppressing the extraction of electrons from a source of negative hydrogen ions and maintaining uniformity, characterized by, include: A discharge chamber equipped with a dual-drive ion source using radio frequency is constructed, and a partition or grid is installed near the outlet of the drive source region. The discharge chamber includes a drive source region, a diffusion region, and a grounded shield. The drive source region is sealed to the diffusion region, and the shield is installed on the outside of the drive source region. The back plate of the drive source region is made of stainless steel, and the side wall is a quartz cylinder. Radio frequency copper wire coils are wound around the outside of the quartz cylinder. Discharge gas is introduced into the discharge chamber, and power is applied to the radio frequency copper wire coil of the driving source region to generate plasma in the discharge chamber. By absorbing electrons through the partition or grid, the common extracted electrons are suppressed, while maintaining plasma homogeneity.

2. The method of suppressing the emission of electrons from a source of negative hydrogen ions and maintaining uniformity according to claim 1, characterized in that, The driving source area includes a stainless steel back plate and a quartz tube sidewall. The outside of the quartz tube is wound with a 5-turn radio frequency copper wire coil. The driving source area is 14cm high and 28cm in diameter. The coil diameter is 29cm and the radio frequency frequency is 2MHz. The driving source area includes two driving sources with a center-to-center distance of 44cm between them.

3. The method of suppressing the extraction of electrons from a source of negative hydrogen ions and maintaining uniformity according to claim 1, characterized in that, The sidewall material of the diffusion zone is 304 stainless steel. The diffusion zone is 100cm long, 50cm wide, and 25cm high. The driving source area and the diffusion zone are sealed and connected by a fluororubber O-ring.

4. The method of suppressing the extraction of electrons from a source of negative hydrogen ions and maintaining uniformity according to claim 1, characterized in that, The material of the partition or grid is nickel-plated copper, tungsten, or molybdenum. When nickel-plated copper is used, the thermal conductivity of copper is used to achieve rapid heat transfer, and the resistance of the nickel plating to plasma erosion and sputtering is used to protect the substrate.

5. The method of suppressing the source of negative hydrogen ions from drawing electrons and maintaining uniformity according to claim 1, wherein, The number of partitions is 10, and the dimensions of the partitions in the x, y, and z directions are 0.5cm, 50cm, and 5cm, respectively. The partitions are located at the boundary between the driving source region and the diffusion region.

6. The method for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity according to claim 1, characterized in that, There are two grids, which are respectively set at the outlets of the two driving sources. The outer dimensions of each grid are 28cm×50cm, and each grid has 3 mesh openings, each mesh opening being 4cm×50cm in size.

7. The method for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity according to claim 1, characterized in that, The method further includes: adjusting the position of the partition or grid along the z-axis; and / or applying a DC bias voltage to the partition or grid to attract electrons to accelerate and impact the partition or grid and cause them to dissipate.

8. A device for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity, characterized in that, The system includes a discharge chamber equipped with a dual-drive ion source for radio frequency (RF), a partition, or a grid. The discharge chamber comprises a drive source region, a diffusion region, and a grounded shield. The back plate of the drive source region is made of stainless steel, and the side wall is a quartz cylinder. An RF copper wire coil is wound around the outside of the quartz cylinder. The diffusion region is sealed to the drive source region. The shield is installed outside the drive source region to prevent RF signals from causing electromagnetic interference to the measuring instrument. The partition or grid is located near the outlet of the drive source region to absorb electrons to suppress common electron extraction and maintain plasma homogeneity.

9. The device for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity according to claim 8, characterized in that, The driving source area is 14cm high and 28cm in diameter. The RF copper wire coil has 5 turns and a diameter of 29cm. The driving source area includes two driving sources with a center-to-center distance of 44cm and an RF frequency of 2MHz. The sidewall of the diffusion area is made of 304 stainless steel. The diffusion area is 100cm long, 50cm wide, and 25cm high. The diffusion area and the driving source area are sealed together by fluororubber O-rings.

10. The device for suppressing the extraction of electrons from a negative hydrogen ion source and maintaining uniformity according to claim 9, characterized in that, The partitions or grids are made of nickel-plated copper, tungsten, or molybdenum. There are 10 partitions with dimensions of 0.5cm, 50cm, and 5cm in the x, y, and z directions, respectively, and they are located at the boundary between the driving source region and the diffusion region. There are 2 grids with an outer dimension of 28cm × 50cm and 3 mesh openings of 4cm × 50cm, respectively located at the outlets of the two driving sources. The partitions or grids can be adjusted in position along the z-axis and can be subjected to DC bias.

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