Plasma electrode hole adjusting mechanism and method for ECR ion source

Abstract

The invention discloses a plasma electrode hole adjusting mechanism and method for an ECR ion source. The plasma electrode hole adjusting mechanism comprises a base, and the periphery of the base is used for being fixedly connected with a beam leading-out end of an electrode cavity of the ECR ion source; a first lead-out hole is formed in the center of the base; a control shielding mechanism is movably connected to the base and can be driven by external force to move to a first position or a second position. The shielding mechanism is controlled to completely expose the first lead-out hole at the first position; the shielding mechanism is controlled to partially shield the first lead-out hole at the second position and form a second lead-out hole, the axial center line of the second lead-out hole coincides with the axial center line of the first lead-out hole, and the aperture of the second lead-out hole is smaller than that of the first lead-out hole; the technical problems that the ECR ion source plasma electrode hole is of a fixed structure, online adjustment of the plasma electrode hole diameter is difficult to achieve, and then online adjustment of leading-out beam parameters is difficult to achieve are solved.

Description

Technical Field

[0001] The invention relates to the technical field of electron cyclotron resonance ion sources, and in particular to a plasma electrode aperture adjustment mechanism and an adjustment method for an ECR ion source. Background Art

[0002] The electron cyclotron resonance (ECR) ion source is an important device that can produce a high-current monovalent ion beam. It uses the interaction between microwaves and magnetic fields to cause electrons to undergo cyclotron resonance and be heated in a specific area, and then ionizes them through collisions between electrons and neutral atoms or molecules to produce an ion beam. The ECR ion source has the advantages of high ion beam intensity and good beam quality, and is widely used in many fields such as nuclear physics research, material science, and medicine.

[0003] In the ECR ion source, the plasma electrode plays a key role. Its design and performance directly determine the intensity and beam stability of the extracted ion beam. A reasonable plasma electrode structure can effectively reduce the space charge effect in the extraction process and improve the ion extraction efficiency. In addition, the plasma electrode of the ECR ion source can affect the parameters such as the energy distribution, emittance and beam stability of the extracted ion beam. By adjusting the shape and size of the plasma electrode aperture, the convergence performance of the extracted ion beam can be improved, the divergence of the beam can be reduced, and the stability of the beam can be improved.

[0004] At present, the plasma electrode holes of ECR ​​ion sources at home and abroad are all fixed structures. When the plasma electrode aperture needs to be adjusted, especially when using the ECR ion source for experiments, it is necessary to first shut down the machine and open the entire electrode chamber, remove the plasma electrode, and then replace the electrode with an adaptive one. Since the structure of the ECR ion source itself is relatively complex, the operation is relatively complicated and inconvenient when removing and replacing the plasma electrode, and it is easy to make operational errors when disassembling and assembling, which may cause the electrode chamber to be contaminated or the vacuum degree to fail to meet the requirements after installation, which may cause the experimental results to be distorted or have large deviations, affecting the experimental conclusions.

[0005] Since current ECR ion sources are unable to adjust the plasma electrode aperture online, and there is a correlation between the plasma electrode aperture and the extracted beam intensity or characteristics, it is difficult to optimize the extracted ion beam characteristics or intensity online, which greatly limits operations such as adjustment of the extracted beam convergence and stability.

[0006] Therefore, in view of the above technical problems, it is necessary to improve the pore structure of the plasma electrode of the ECR ion source and realize online adjustment of the plasma electrode pore size. Summary of the invention

[0007] The purpose of the present invention is to provide a plasma electrode aperture adjustment mechanism and an adjustment method for an ECR ion source, so as to solve the technical problem that the plasma electrode aperture of the ECR ion source in the prior art is a fixed structure, which makes it difficult to achieve online adjustment of the plasma electrode aperture, and further makes it difficult to achieve online adjustment of the extracted beam intensity or characteristics.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] On the one hand, the present invention provides a plasma electrode hole adjustment mechanism for an ECR ion source, comprising a base, the outer periphery of the base being fixedly connected to the beam extraction end of the electrode chamber of the ECR ion source; a first extraction hole is opened at the center of the base, and the first extraction hole is used to extract the plasma beam; a control shielding mechanism is movably connected to the base, and the control shielding mechanism can move to a first position or a second position under the drive of an external force; the control shielding mechanism can fully expose the first extraction hole at the first position; the control shielding mechanism can partially shield the first extraction hole and form a second extraction hole at the second position, the axial center line of the second extraction hole coincides with the axial center line of the first extraction hole, and the aperture of the second extraction hole is smaller than the aperture of the first extraction hole. This solution controls the shielding mechanism to partially shield the first lead-out hole or expose the first lead-out hole completely, thereby realizing online regulation of the size of the first lead-out hole without disassembling the electrode chamber. This can solve the technical problem in the prior art that the plasma electrode hole of the ECR ion source is a fixed structure, which makes it difficult to achieve online regulation of the plasma electrode aperture, and further makes it difficult to achieve online adjustment of the extraction beam intensity or characteristics.

[0010] Preferably, the control shielding mechanism includes a turntable, a splicing leaf and a transmission mechanism, the rotating surface of the turntable is arranged parallel to the hole cross section of the first lead-out hole, the turntable is rotationally connected to the base; the turntable is transmission-connected to the transmission mechanism; the transmission mechanism extends from the outside of the electrode chamber into the inside of the electrode chamber, and the transmission mechanism can be driven by an external force and drive the turntable to rotate forward or reverse, thereby switching the control shielding mechanism between the first position and the second position. Since the lead-out end space of the electrode chamber is limited, the use of a rotation switching method can save installation space. At the same time, the turntable is driven to rotate by the transmission mechanism, which can avoid the disassembly and assembly of the electrode chamber, and the turntable can be rotated by driving the transmission mechanism outside the electrode chamber.

[0011] Preferably, the turntable is provided with a plurality of slides, each of which is inclined and symmetrically distributed with the center of the turntable surface as the center of the circle; there are a plurality of splicing leaves and the number corresponds to the slides, the splicing leaves include a first end, a second end and a third end, the first end of each of the splicing leaves is respectively slidably connected to the corresponding slide; the second end of each of the splicing leaves is respectively rotatably connected to the base; when the first end of each of the splicing leaves slides in the slide, the third end of each of the splicing leaves can respectively rotate with the corresponding second end as the center of the circle, so that the control shielding mechanism can switch between the first position and the second position.

[0012] Specifically, when the turntable rotates forward or reversely, it can drive each of the spliced ​​leaves to rotate along the corresponding slides. When the first end of each of the spliced ​​leaves is at one end of the slide, corresponding to the first position of the control shielding mechanism, each of the spliced ​​leaves is dispersed to the outer edge of the peripheral side of the first lead-out hole, so that the first lead-out hole is fully exposed; when the first end of each of the spliced ​​leaves is at the other end of the slide, corresponding to the second position of the control shielding mechanism, each of the spliced ​​leaves partially shields the first lead-out hole, and they are spliced ​​together to form a second lead-out hole, the axial center line of the second lead-out hole coincides with the axial center line of the first lead-out hole, and the aperture of the second lead-out hole is smaller than the aperture of the first lead-out hole.

[0013] Preferably, the base has a protrusion at the center, the extension direction of the protrusion is parallel to the axial direction of the first lead-out hole, and the first lead-out hole is located at the center of the protrusion; the turntable is rotatably connected to the outer periphery of the protrusion, and the second ends of the respective spliced ​​leaves are rotatably connected to the protrusion; there is a gap between the disk surface of the turntable and the base. The protrusion is provided to serve as the rotating axis of the turntable. In addition, the protrusion can also create a gap between the rotating surface of the turntable and the base, so that when the turntable rotates, no friction is generated between the turntable and the base, making the rotation process smoother.

[0014] Preferably, the cross-sectional shape of the first lead-out hole is circular, and the cross-sectional shape of the second lead-out hole is circular.

[0015] As one embodiment of the splicing leaf, the number of the splicing leaves is n, each of the third ends has a first arc cylinder, the radius of the cross-sectional arc of the first arc cylinder is equal to the cross-sectional radius of the second lead-out hole, and the arc length of the cross-sectional arc of each of the first arc cylinder is equal to 1 / n of the circumference of the cross-sectional area of ​​the second lead-out hole;

[0016] The second end of the splicing leaf has a second arc cylindrical surface, and the corresponding first end has a third arc cylindrical surface, and the second arc cylindrical surface matches the third arc cylindrical surface; when the splicing leaves are spliced ​​to form a second lead-out hole, when two adjacent splicing leaves are spliced, the second arc cylindrical surface of one of the splicing leaves and the third arc cylindrical surface of the other splicing leaf abut against each other and splice.

[0017] Preferably, the joint seam between two adjacent joint leaves is a staggered seam, which can reduce the possibility of beam leakage from the joint seam due to a larger joint seam after jointing, and ensure that all beams are led out from the second lead-out hole.

[0018] Preferably, the transmission mechanism includes a transmission rod, both ends of which extend out from the side walls of the electrode chamber respectively, and the outer side walls of the electrode chamber are respectively provided with a first vacuum sealing structure and a second vacuum sealing structure corresponding to the two ends of the transmission rod, and the two ends of the transmission rod can move in the first vacuum sealing structure and the second vacuum sealing structure respectively; the transmission rod is slidingly connected to the side wall of the electrode chamber, and the transmission rod can slide along a straight line; one end of a rocker is rotatably connected to the transmission rod, and the other end of the rocker is rotatably connected to the rotating shielding assembly; when the transmission rod slides forward or backward, it can drive the rocker and drive the rotating shielding assembly to rotate forward or reverse.

[0019] In order to meet more electrode aperture adjustment requirements, the splicing shape of each splicing leaf is further improved. The first end of each splicing leaf is respectively connected to the base for rotation, and is also connected to the turntable for transmission at the same time. Among two adjacent splicing leaves, the second end of one splicing leaf is stacked with the third end of the other splicing leaf. The third end of each splicing leaf can be spliced ​​into a third lead-out hole. The cross-sectional shapes of the second and third lead-out holes are both regular polygons, and the number of sides of the regular polygon is greater than or equal to 5. The cross-sectional area of ​​the third lead-out hole is greater than the cross-sectional area of ​​the second lead-out hole, and smaller than the cross-sectional area of ​​the first lead-out hole. At the same time, the cross-sectional area of ​​the third lead-out hole is correlated with the telescopic length of the transmission rod. The use of this shape of splicing leaf can realize the stepless regulation of the electrode aperture, enhance the adjustability of the electrode aperture, make it more flexible to adjust the state of the extracted ion beam, obtain the extracted ion beam with different convergence performance, increase the type of ECR ​​ion source output beam, and be more conducive to experimental use.

[0020] On the other hand, the present invention also provides a plasma electrode aperture adjustment method for an ECR ion source, using the plasma electrode aperture adjustment mechanism for an ECR ion source as described above, comprising the following steps:

[0021] S1, setting a plurality of transmission rod telescopic values, and obtaining a corresponding plasma electrode hole aperture value according to each transmission rod telescopic value, to form a plurality of associated data sets of transmission rod telescopic values ​​and plasma electrode hole aperture values;

[0022] S2. By fitting all the associated data groups, a fitting relationship between the telescopic length of the transmission rod and the aperture of the plasma electrode hole is obtained;

[0023] S3, preset a target plasma electrode hole diameter value, and reversely calculate the target telescopic value of the transmission rod according to the fitting relationship between the telescopic length of the transmission rod and the plasma electrode hole diameter obtained in step S4;

[0024] S4. Control the transmission rod to extend or retract to a target extension or retraction value to adjust the aperture of the plasma electrode hole.

[0025] The present invention has the following beneficial effects: the plasma electrode aperture adjustment mechanism for an ECR ion source disclosed in the present invention realizes the switching of the control shielding mechanism between a first position and a second position by splicing or not of a plurality of splicing leaves, thereby realizing the shielding of the first lead-out hole, and realizing the adjustment of the plasma electrode aperture without replacing the plasma electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to make the purpose, technical solution and advantages of the invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0027] Figure 1 It is a cross-sectional schematic diagram of the installation position of the plasma electrode hole adjustment mechanism according to an embodiment of the present invention.

[0028] Figure 2 It is a front view of the plasma electrode hole adjustment mechanism according to an embodiment of the present invention.

[0029] Figure 3 It is a rear view of the plasma electrode hole adjustment mechanism according to an embodiment of the present invention.

[0030] Figure 4 It is an exploded view of the relative position relationship structure of the base and the turntable in an embodiment of the present invention.

[0031] Figure 5 The figure is a schematic diagram of the overall structure of the spliced ​​leaf according to an embodiment of the present invention.

[0032] Figure 6 It is a front view of the spliced ​​leaf according to an embodiment of the present invention.

[0033] Figure 7 Schematic diagram of the first position structure of an embodiment of the present invention.

[0034] Figure 8Schematic diagram of the second position structure of an embodiment of the present invention.

[0035] Fig. 9 It is a schematic diagram of the overall structure of the preferred spliced ​​leaf according to an embodiment of the present invention.

[0036] Fig.10 for Fig. 9 Schematic diagram of the optimal structure of the splicing leaves in .

[0037] Fig.11 2 is a cross-sectional view of a transmission mechanism according to an embodiment of the present invention.

[0038] Fig.12 It is a schematic diagram of the structure of the spliced ​​leaves in Example 10 of the present invention.

[0039] Fig.13 Schematic diagram of the splicing position of the splicing leaves in Example 10 of the present invention.

[0040] Explanation of the reference numerals: 1. base; 11. protrusion; 12. shaft hole; 21. turntable; 211. slideway; 221. transmission rod; 222. rocker; 223. second rotating shaft; 224. third rotating shaft; 225. first telescopic tube; 226. drive motor; 227. second telescopic tube; 31. first lead-out hole; 32. second lead-out hole; 33. third lead-out hole; 4. splicing leaf; 41. first end; 411. third circular arc cylinder; 412. extension portion; 413. sliding shaft; 414. coupling portion; 42. second end; 421. second circular arc cylinder; 422. first rotating shaft; 423. support platform; 43. third end; 431. first circular arc cylinder; 51. electrode chamber; 52. electrode; 53. lead-out chamber. DETAILED DESCRIPTION

[0041] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0042] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] The present invention can be applied to the aperture adjustment of the plasma electrode hole in the ECR ion source, solving the technical problem in the prior art that the plasma electrode hole of the ECR ion source is a fixed structure, which makes it difficult to adjust the plasma electrode aperture online, and further makes it difficult to adjust the extracted beam intensity or characteristics online.

[0044] In order to explain the technical solution of the present invention in detail, the following specific embodiments are given.

[0045] Example 1, please refer to Figure 1 and Figure 2The present embodiment provides a plasma electrode hole adjustment mechanism for an ECR ion source, comprising a base 1, the outer periphery of the base 1 being fixedly connected to the beam extraction end of the electrode chamber 51 of the ECR ion source; a first extraction hole 31 is opened at the center of the base 1, and the first extraction hole 31 is used to extract the plasma beam; a control shielding mechanism is movably connected to the base 1, and the control shielding mechanism can move to a first position or a second position under the drive of an external force; the control shielding mechanism can realize full exposure of the first extraction hole 31 at the first position; the control shielding mechanism can partially shield the first extraction hole 31 at the second position and form a second extraction hole 32, the axial center line of the second extraction hole 32 coincides with the axial center line of the first extraction hole 31, and the aperture of the second extraction hole 32 is smaller than the aperture of the first extraction hole 31. This solution controls the shielding mechanism to partially shield the first lead-out hole 31 or expose the first lead-out hole 31 completely, thereby realizing online regulation of the size of the first lead-out hole 31 without disassembling the electrode chamber 51. This can solve the technical problem in the prior art that the plasma electrode hole of the ECR ion source is a fixed structure, which makes it difficult to achieve online regulation of the plasma electrode aperture, and further makes it difficult to achieve online adjustment of the extraction beam intensity or characteristics.

[0046] Specifically, in Example 1, please refer to Figure 1 The beam extraction end is located between the electrode chamber 51 and the extraction chamber 53, and the extraction chamber 53 is used to extract the beam.

[0047] Specifically, in Example 1, please refer to Figure 1 A plurality of electrodes 52 are installed in the electrode chamber 51 of the ECR ion source. Each electrode 52 has an extraction hole. The axial center lines of the extraction holes of each electrode 52 coincide with each other and coincide with the axial center line of the first extraction hole 31 .

[0048] Embodiment 2, on the basis of embodiment 1, the control shielding mechanism includes a turntable 21, a splicing leaf 4 and a transmission mechanism, the rotating surface of the turntable 21 is arranged parallel to the hole cross section of the first lead-out hole 31, the turntable 21 is rotationally connected to the base 1; the turntable 21 is transmission-connected to the transmission mechanism; the transmission mechanism extends from the outside of the electrode 52 chamber 51 into the inside of the electrode 52 chamber 51, and the transmission mechanism can be driven by an external force and drive the turntable 21 to rotate forward or reverse, thereby switching the control shielding mechanism between the first position and the second position. Since the lead-out end space of the electrode chamber 51 is limited, the use of a rotation switching method can save installation space. At the same time, the turntable is driven by the transmission mechanism to rotate, which can avoid the disassembly and assembly of the electrode chamber 51, and the rotation of the turntable can be achieved by driving the transmission mechanism outside the electrode chamber 51.

[0049] Example 3, based on Example 2, please refer to Figures 2 to 4 The turntable 21 is provided with a plurality of slideways 211, each of which is inclined and symmetrically distributed with the center of the turntable 21 as the center of the circle; there are a plurality of splicing leaves 4 and the number corresponds to the slideways 211, the splicing leaves 4 include a first end 41, a second end 42 and a third end 43, the first end 41 of each of the splicing leaves 4 is respectively slidably connected to the corresponding slideway 211; the second end 42 of each of the splicing leaves 4 is respectively rotatably connected to the base 1; when the first end 41 of each of the splicing leaves 4 slides in the slideway 211, the third end 43 of each of the splicing leaves 4 can respectively rotate with the corresponding second end 42 as the center of the circle, so that the control shielding mechanism switches between the first position and the second position. Specifically, when the turntable 21 rotates forward or reversely, it can drive each of the spliced ​​leaves 4 to rotate along the corresponding slideways 211. When the first end 41 of each of the spliced ​​leaves 4 is at one end of the slideway 211, corresponding to the first position of the control shielding mechanism, each of the spliced ​​leaves 4 is dispersed to the outer edge of the peripheral side of the first lead-out hole 31, so that the first lead-out hole 31 is fully exposed; when the first end 41 of each of the spliced ​​leaves 4 is at the other end of the slideway 211, corresponding to the second position of the control shielding mechanism, each of the spliced ​​leaves 4 partially shields the first lead-out hole 31, and they are spliced ​​together to form a second lead-out hole 32, the axial center line of the second lead-out hole 32 coincides with the axial center line of the first lead-out hole 31, and the aperture of the second lead-out hole 32 is smaller than the aperture of the first lead-out hole 31.

[0050] Specifically, in Example 3, please refer to Figures 2 to 4 The rotating disk 21 is a disk structure, and each slideway 211 is inclined relative to the radial line of the rotating disk 21. Each first end 41 has a sliding shaft 413, and each sliding shaft 413 is slidably connected to the corresponding slideway 211.

[0051] Example 4, based on Example 3, please refer to Figures 2 to 4 The base 1 has a protrusion 11 at its center, and the extension direction of the protrusion 11 is axially parallel to the first lead-out hole 31, and the first lead-out hole 31 is located at the center of the protrusion 11; the turntable 21 is rotatably connected to the outer periphery of the protrusion 11, and the second ends 42 of each of the spliced ​​leaves 4 are rotatably connected to the protrusion 11; there is a gap between the disk surface of the turntable 21 and the base 1. The protrusion 11 is provided to serve as the rotating axis of the turntable 21. In addition, the protrusion 11 can also create a gap between the rotating surface of the turntable 21 and the base 1, so that when the turntable 21 rotates, no friction will be generated between the turntable 21 and the base 1, making the rotation process smoother. Specifically, in Example 4, please refer to Figures 2 to 4A plurality of shaft holes 12 are evenly formed on the protruding portion 11 , and the second end 42 of each of the split leaves 4 has a plurality of first rotating shafts 422 , respectively. Each of the first rotating shafts 422 is rotatably connected to each of the shaft holes 12 .

[0052] Embodiment 5, based on any one of embodiments 1 to 4, the cross-sectional shape of the first lead-out hole 31 is circular, and the cross-sectional shape of the second lead-out hole 32 is circular. Then, the second lead-out hole 32 also coincides with the axial center line of the lead-out hole of each electrode 52.

[0053] Example 6, based on Example 5, please refer to Figure 5 to Figure 6 , one embodiment of the splicing leaf 4 is provided, the number of the splicing leaves 4 is n, each of the third ends 43 has a first arc cylinder 431, the radius of the cross-sectional arc of the first arc cylinder 431 is equal to the cross-sectional radius of the second outlet hole 32, and the arc length of the cross-sectional arc of each of the first arc cylinder 431 is equal to 1 / n of the circumference of the cross-sectional area of ​​the second outlet hole 32; the second end 42 of the splicing leaf 4 has a second arc cylinder 421, and the corresponding first end 41 has a third arc cylinder 411, and the second arc cylinder 421 matches the third arc cylinder 411; when each of the splicing leaves 4 is spliced ​​to form the second outlet hole 32, when two adjacent splicing leaves 4 are spliced, the second arc cylinder 421 of one of the splicing leaves 4 and the third arc cylinder 411 of the other splicing leaf 4 abut against each other and splice. Specifically, in Embodiment 6, please refer to Figures 2 to 6 The first end 41 of the spliced ​​leaf 4 has an extension portion 412 , the third arc cylindrical surface 411 is located on a side of the extension portion 412 away from the second end 42 , and the sliding shaft 413 is located at the free end of the extension portion 412 .

[0054] Example 7, as a preferred embodiment of Example 6, please refer to Figure 5 to Figure 6 The number of the spliced ​​leaves 4 is n=5, and the length of the arc of the cross section of each of the first arc cylinders 431 is equal to 1 / 5 of the circumference of the cross section of the second lead-out hole 32. Correspondingly, five shaft holes 12 are evenly opened on the protrusion 11.

[0055] Example 8, based on Example 6, please refer to Figures 9 and 10 The joint seam between two adjacent joint leaves 4 is a staggered seam, which can reduce the possibility of beam leakage from the joint seam due to a larger joint seam after jointing, and ensure that all beams are led out from the second lead-out hole 32 .

[0056] Example 9, based on Example 8, please refer to Figures 9 and 10, one of the implementation methods of the staggered seam is provided, the first end 41 of the splicing leaf 4 also has a coupling portion 414, the coupling portion 414 extends outward from one end of the third arc cylindrical surface 411 along the thickness direction of the splicing leaf 4, the extension direction of the coupling portion 414 is perpendicular to the thickness direction of the splicing leaf 4, and the thickness of the coupling portion 414 is less than the thickness of the splicing leaf 4; correspondingly, the second end 42 is used for the part spliced ​​with the first end 41, and corresponds to the coupling portion 414 being sunken inward to form a support platform 423, and the side wall height of the support platform 423 is equal to the thickness of the coupling portion 414; when two adjacent splicing leaves 4 are spliced ​​together, the coupling portion 414 of one splicing leaf 4 can be spliced ​​with the support platform 423 of the other splicing leaf 4. In this way, when two adjacent splicing leaves 4 are spliced ​​together, an extended side of the coupling portion 414 of one of the splicing leaves 4 is placed on the support platform 423 of the other splicing leaf 4, and the end face of the extended end of the coupling portion 414 of one of the splicing leaves 4 abuts and splices with the side wall of the support platform 423 of the other splicing leaf 4, and the end face of the extended end of the coupling portion 414 of one of the splicing leaves 4 has the same curvature as the side wall of the support platform 423 of the other splicing leaf 4; at the same time, the third arc cylindrical surface 411 of the first end 41 of one of the splicing leaves 4 excluding the coupling portion 414 and the second arc cylindrical surface 421 of the second end 42 of the other splicing leaf 4 excluding the support platform 423 abuts and splices with each other; after splicing in this form, the splicing seams between the splicing leaves 4 are offset seams, which can reduce the possibility of a large splicing seam after splicing, resulting in beam leakage from the splicing seam, and can ensure that all beams are drawn out from the second lead-out hole 32.

[0057] Example 10, please refer to Figure 12 to Figure 13On the basis of Example 2, in order to meet more electrode aperture adjustment requirements, the splicing shape of each splicing leaf is further improved, and the first end 41 of each splicing leaf 4 is respectively rotatably connected to the base 1, and at the same time is respectively transmission-connected to the turntable 21; among two adjacent splicing leaves 4, the second end 42 of one splicing leaf 4 is stacked with the third end 43 of the other splicing leaf 4; the third end 43 of each splicing leaf 4 can be spliced ​​into a third lead-out hole 33, and the cross-sectional shapes of the second lead-out hole 32 and the third lead-out hole 33 are both regular polygons, and the number of sides of the regular polygon is greater than or equal to 5; the cross-sectional area of ​​the third lead-out hole 33 is larger than the cross-sectional area of ​​the second lead-out hole 32, and smaller than the cross-sectional area of ​​the first lead-out hole 31; at the same time, the cross-sectional area of ​​the third lead-out hole 33 is correlated with the telescopic length of the transmission rod 221. The use of this shape of splicing leaves can realize stepless regulation of the electrode aperture, so that the adjustability of the electrode aperture is enhanced, and the state of the extracted ion beam can be adjusted more flexibly, so as to obtain extracted ion beams with different convergence properties, increase the types of ECR ​​ion source output beams, and be more conducive to experimental use. Of course, in actual applications, the electrode hole is preferably circular to facilitate the unimpeded passage of the beam, so the number of splicing leaves needs to be set as much as possible according to the actual situation, so that the shape of the regular polygon can be close to a circle, for example, setting more than or equal to 12 splicing leaves, or more than or equal to 24 splicing leaves; or, in actual applications, the outer shape of one end of each splicing leaf used to splice into the second extraction hole and the third extraction hole is set to be an arc shape with the same bending direction, so that the cross-sectional shape of the spliced ​​hole is a centrally symmetrical figure, and is closer to a circle. As one of the implementation modes in which the first ends 41 of each spliced ​​leaf 4 are respectively connected to the turntable 21 in a transmission manner, each spliced ​​leaf is rotatably connected to the base via a first rotating shaft, a gear ring is provided on the circumferential side of the turntable, and gears are respectively fixed on the corresponding first rotating shafts, and each gear is respectively engaged with the gear ring. When the turntable rotates, it can drive each gear to rotate, and then drive each spliced ​​leaf to rotate, so as to adjust the size of the third lead-out hole; in this process, the telescopic length of the transmission rod is correlated with the rotation angle of the turntable, and the rotation angle of the turntable is correlated with the size of the third lead-out hole, so as to obtain the relationship between the telescopic length of the transmission rod and the size of the third lead-out hole, and the size of the third lead-out hole can be adjusted by adjusting the telescopic length of the transmission rod.

[0058] Embodiment 11, based on any of the above embodiments, please refer to Figure 1 and Fig.11The transmission mechanism includes a transmission rod 221, the two ends of which extend from the side wall of the electrode chamber 51 respectively, and the outer side wall of the electrode chamber 51 is provided with a first vacuum sealing structure and a second vacuum sealing structure respectively corresponding to the two ends of the transmission rod 221, and the two ends of the transmission rod 221 can move in the first vacuum sealing structure and the second vacuum sealing structure respectively; the transmission rod 221 is slidably connected to the side wall of the electrode chamber 51, and the transmission rod 221 can slide along a straight line; one end of a rocking arm 222 is rotatably connected to the transmission rod 221, and the other end of the rocking arm 222 is rotatably connected to the rotating shielding assembly; when the transmission rod 221 slides forward or backward, it can drive the rocking arm 222 and drive the rotating shielding assembly to rotate forward or reverse. Specifically, in Example 12, the transmission rod 221 is rotatably connected to one end of the rocking arm 222 through a second rotating shaft 223, and the other end of the rocking arm 222 is rotatably connected to the turntable 21 through a third rotating shaft 224. Specifically, the transmission rod 221, the rocker 222 and the rotating shielding assembly are all made of shielding materials. Specifically, the transmission rod 221 and the rocker 222 are both rectangular in shape.

[0059] Example 12, based on Example 7 and Example 11, please refer to Figure 1 and Fig.11 As one of the implementation methods of the transmission mechanism to realize the linear sliding of the driving transmission rod 221, the first vacuum sealing structure is a first telescopic tube 225, and the second vacuum sealing structure is a second telescopic tube 227. One end of the first telescopic tube 225 is sealed and fixed on the outer wall of the electrode chamber 51, and the other end of the first telescopic tube 225 is sealed and fixed with a driving motor 226; the output end of the driving motor 226 can be telescopic, and the output end extends into the first telescopic tube 225, and the first telescopic tube 225 is vacuum; one end of the transmission rod 221 extending out of the electrode chamber 51 extends into the telescopic tube and is fixedly connected to the output end; the other end of the transmission rod 221 extending out of the electrode chamber 51 is sealed and fixed with one end of the second telescopic tube 227, and the other end of the second telescopic tube 227 is sealed and fixed on the corresponding outer wall of the electrode chamber 51, and the maximum extension length of the second telescopic tube 227 matches the maximum length of the other end of the transmission rod 221 extending out of the electrode chamber 51, and the second telescopic tube 227 is vacuum. Through the above structure, the plasma electrode hole adjustment mechanism can maintain the vacuum state in the electrode chamber 51 without breaking the vacuum when in use, and the plasma electrode hole can be adjusted by adjusting the motion parameters of the drive motor 226. Specifically, in Example 13, the first telescopic tube 225 and the second telescopic tube 227 are bellows.

[0060] The working process of Example 12 is: Please refer to Figures 7 and 8 When the control shielding mechanism needs to be moved to the first position, the driving mechanism drives the transmission rod 221 to make a linear motion, the transmission rod 221 drives the rocker 222 to make a rotational motion through the second rotating shaft 223, and the rocker 222 drives the turntable 21 to make a rotational motion around the base 1 through the third rotating shaft 224, and the turntable 21 drives the five spliced ​​leaves 4 to rotate around their respective first rotating shafts 422, and correspondingly, each sliding shaft 413 slides to one end of the corresponding slideway 211. At this time, the driving mechanism controls the transmission rod 221 to stop the linear motion, and the first lead-out hole 31 is fully exposed; when the control shielding mechanism needs to be moved to the first position, the driving mechanism drives the transmission rod 221 to stop the linear motion, and the first lead-out hole 31 is fully exposed; When the shielding mechanism moves to the second position, the driving mechanism drives the transmission rod 221 to make a reverse linear motion, the transmission rod 221 drives the rocker 222 to make a reverse rotational motion through the second rotating shaft 223, and the rocker 222 drives the turntable 21 to make a reverse rotational motion around the base 1 through the third rotating shaft 224, and the turntable 21 drives the five spliced ​​leaves 4 to rotate in the opposite direction around the corresponding first rotating shaft 422, and correspondingly, each sliding shaft 413 slides to the other end of the corresponding slideway 211, at which time the driving mechanism controls the transmission rod 221 to stop the linear motion, and each spliced ​​leaf 4 is spliced ​​to form a second lead-out hole 32. In actual operation, the small aperture size composed of the five spliced ​​leaves 4 and the inner diameter size of the base 1 can be changed according to actual needs, so as to achieve the conversion of two apertures of different sizes.

[0061] Embodiment 13, based on any of the above embodiments, the material of the split leaf 4 is graphite or molybdenum. Graphite or molybdenum has the advantages of good electrical and thermal conductivity, heat resistance, sputtering resistance, and high temperature resistance. When the technical solution of any of the above embodiments is adopted, especially when the second lead-out hole 32 or the third lead-out hole is used, a part of the plasma will hit each split leaf 4. The use of graphite or molybdenum material can reduce the possibility of local overheating, erosion of the split leaf 4, thereby causing structural damage / local fracture, and charge accumulation on the split leaf 4, thereby affecting the electrical performance, which is conducive to the stable operation of the plasma electrode hole adjustment mechanism and prolonging the service life of the plasma electrode hole adjustment mechanism.

[0062] Embodiment 14, based on Embodiment 2 and Embodiment 10, provides a plasma electrode aperture adjustment method for an ECR ion source, using the plasma electrode aperture adjustment mechanism for an ECR ion source as described in Embodiment 2 and Embodiment 10 above, comprising the following steps:

[0063] S1, setting a plurality of transmission rod telescopic values, and obtaining a corresponding plasma electrode hole aperture value according to each transmission rod telescopic value, to form a plurality of associated data sets of transmission rod telescopic values ​​and plasma electrode hole aperture values;

[0064] S2. By fitting all the associated data groups, a fitting relationship between the telescopic length of the transmission rod and the aperture of the plasma electrode hole is obtained;

[0065] S3, preset a target plasma electrode hole diameter value, and reversely calculate the target telescopic value of the transmission rod 221 according to the fitting relationship between the telescopic length of the transmission rod and the plasma electrode hole diameter obtained in step S4;

[0066] S4, controlling the transmission rod 221 to extend or retract to a target extension or retraction value, so as to adjust the aperture of the plasma electrode hole.

[0067] Specifically, in Example 14, the adjustment range of the aperture value of the plasma electrode hole is 8 to 15 mm.

[0068] Specifically, in Example 14, in step S1, the corresponding plasma electrode hole diameter value is obtained according to the telescopic value of each transmission rod, which is achieved by actual measurement or construction of a simulation motion model of the plasma electrode hole adjustment mechanism.

[0069] Specifically, in Example 14, in step S3, the preset target plasma electrode aperture value is determined according to the required extraction beam intensity. Here, an embodiment of the correlation between the preferred target plasma electrode aperture value and the extraction beam intensity is given, as shown in Table 1:

[0070] Table 1 Correlation between target plasma electrode aperture value and extracted beam intensity

[0071] Target plasma electrode hole diameter / mm Extracted beam intensity / mA 9 100 10 130 11 150

[0072] Specifically, in Example 14, in step S4, controlling the transmission rod to be extended to the target extension value is achieved by the following method steps:

[0073] S4.1. A driving mechanism is fixed at one end of the transmission rod, and the driving mechanism can drive the transmission rod to move linearly;

[0074] S4.2, setting a control system, wherein the control system is electrically connected to the driving mechanism, and the control system is used to control the driving mechanism to operate according to the set parameter value;

[0075] S4.3, constructing a correlation between the operating parameters of the driving mechanism and the telescopic value of the transmission rod;

[0076] S4.4, constructing a conversion relationship between the target plasma electrode hole aperture value and the transmission rod telescopic value in the control system, and a conversion relationship between the transmission rod telescopic value and the operating parameters of the driving mechanism;

[0077] S4.5. Input the target plasma electrode hole diameter value into the control system, and the control system obtains the operating parameters of the driving mechanism according to the corresponding conversion relationship in turn, and sends operating instructions to the driving mechanism according to the operating parameters to control the operation of the driving mechanism and realize the adjustment of the plasma electrode hole diameter.

[0078] Specifically, in Example 14, the driving mechanism uses a motor with a linear telescopic end or a rotating motor with a gear transmission system, and the gear transmission system can convert rotational kinetic energy into linear kinetic energy.

[0079] The plasma electrode hole adjustment mechanism and adjustment method for the ECR ion source disclosed in the present invention have the following technical effects:

[0080] 1. The plasma electrode aperture adjustment mechanism for the ECR ion source realizes the switching of the shielding mechanism between the first position and the second position by splicing or not of a plurality of splicing leaves, thereby realizing the shielding of the first lead-out hole, and realizing the adjustment of the plasma electrode aperture without replacing the plasma electrode.

[0081] 2. Through the transmission mechanism that does not break the vacuum, the aperture of the plasma electrode hole can be adjusted online, thereby adjusting the state of the extracted ion beam online and optimizing the convergence performance of the extracted ion beam.

[0082] 3. The plasma electrode aperture adjustment mechanism for the ECR ion source of the present invention has the advantages of high efficiency, high flexibility, time saving and good economy.

[0083] 4. By obtaining multiple sets of correlation data groups of transmission rod telescopic values ​​and plasma electrode hole diameter values, and fitting to obtain the fitting relationship between the transmission rod telescopic length and the plasma electrode hole diameter, the theoretical values ​​​​and the actual operation values ​​​​can be combined to the greatest extent, which has effective guiding significance for actual operations.

[0084] It is understood that the present invention is described by some embodiments, and those skilled in the art are aware that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. The embodiments described in the present invention are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein may be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all other embodiments obtained by ordinary technicians in the art without creative work based on the embodiments in the present invention belong to the scope of protection of the present invention.

Claims

1. A plasma electrode aperture adjustment mechanism for an ECR ion source, characterized in that: It includes a base, the outer periphery of which is used for fixed connection with the beam extraction end of the electrode chamber of the ECR ion source; a first extraction hole is opened in the center of the base, and the first extraction hole is used to extract the plasma beam; a control shielding mechanism is movably connected to the base, and the control shielding mechanism can move to a first position or a second position under the drive of an external force; the control shielding mechanism can realize full exposure of the first extraction hole in the first position; the control shielding mechanism can partially shield the first extraction hole in the second position and form a second extraction hole, the axial center line of the second extraction hole coincides with the axial center line of the first extraction hole, and the aperture of the second extraction hole is smaller than the aperture of the first extraction hole.

2. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 1, characterized in that: The control shielding mechanism includes a turntable, a splicing leaf and a transmission mechanism. The rotating surface of the turntable is arranged parallel to the hole cross-section of the first lead-out hole. The turntable is rotatably connected to the base; the turntable is transmission-connected to the transmission mechanism; the transmission mechanism extends from the outside of the electrode chamber into the inside of the electrode chamber. The transmission mechanism can be driven by an external force and drive the turntable to rotate forward or reverse, thereby switching the control shielding mechanism between the first position and the second position.

3. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 2, characterized in that: The turntable is provided with a plurality of slides, each of which is inclined and symmetrically distributed with the center of the turntable as the center of the circle; there are a plurality of splicing leaves and the number corresponds to the slides, the splicing leaves include a first end, a second end and a third end, the first end of each of the splicing leaves is respectively slidably connected to the corresponding slide; the second end of each of the splicing leaves is respectively rotatably connected to the base; when the first end of each of the splicing leaves slides in the slide, the third end of each of the splicing leaves can respectively rotate with the corresponding second end as the center of the circle, so that the control shielding mechanism is switched between the first position and the second position.

4. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 3, characterized in that: A protrusion is provided at the center of the base, the extension direction of the protrusion is parallel to the axial direction of the first lead-out hole, and the first lead-out hole is located at the center of the protrusion; the turntable is rotatably connected to the outer periphery of the protrusion, and the second ends of each of the spliced ​​leaves are rotatably connected to the protrusion; there is a gap between the turntable surface and the base.

5. The plasma electrode aperture adjustment mechanism for an ECR ion source according to any one of claims 1 to 4, characterized in that: The cross-sectional shape of the first lead-out hole is circular, and the cross-sectional shape of the second lead-out hole is circular.

6. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 5, characterized in that: The number of the splicing leaves is n, and each of the third ends has a first arc cylinder, the radius of the cross-sectional arc of the first arc cylinder is equal to the cross-sectional radius of the second lead-out hole, and the arc length of the cross-sectional arc of each of the first arc cylinder is equal to 1 / n of the circumference of the cross-sectional area of ​​the second lead-out hole; the second end of the splicing leaf has a second arc cylinder, and the corresponding first end has a third arc cylinder, and the second arc cylinder matches the third arc cylinder; when each of the splicing leaves is spliced ​​to form the second lead-out hole, when two adjacent splicing leaves are spliced, the second arc cylinder of one of the splicing leaves abuts against and splices with the third arc cylinder of the other splicing leaf.

7. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 6, characterized in that: The joint seam between two adjacent joint leaves is a staggered seam.

8. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 2, characterized in that: The transmission mechanism includes a transmission rod, and both ends of the transmission rod extend from the side walls of the electrode chamber respectively. The outer side walls of the electrode chamber are respectively provided with a first vacuum sealing structure and a second vacuum sealing structure corresponding to the two ends of the transmission rod, and the two ends of the transmission rod can move in the first vacuum sealing structure and the second vacuum sealing structure respectively; the transmission rod is slidingly connected to the side wall of the electrode chamber, and the transmission rod can slide along a straight line; one end of the rocker is rotatably connected to the transmission rod, and the other end of the rocker is rotatably connected to the rotating shielding assembly; when the transmission rod slides forward or backward, it can drive the rocker and drive the rotating shielding assembly to rotate forward or reverse.

9. The plasma electrode aperture adjustment mechanism for an ECR ion source according to claim 8, characterized in that: The first ends of the respective splicing leaves are rotatably connected to the base, and are simultaneously transmission-connected to the turntable; the second end of one of the two adjacent splicing leaves is stacked with the third end of the other splicing leaf; the third end of each splicing leaf can be spliced ​​into a third lead-out hole, the cross-sectional shapes of the second lead-out hole and the third lead-out hole are both regular polygons, and the number of sides of the regular polygon is greater than or equal to 5; the cross-sectional area of ​​the third lead-out hole is greater than the cross-sectional area of ​​the second lead-out hole, and smaller than the cross-sectional area of ​​the first lead-out hole; and the cross-sectional area of ​​the third lead-out hole is correlated with the telescopic length of the transmission rod.

10. A plasma electrode aperture adjustment method for an ECR ion source, using the plasma electrode aperture adjustment mechanism for an ECR ion source as claimed in claim 9, characterized in that: The following steps are involved: S1, setting a plurality of transmission rod telescopic values, and obtaining a corresponding plasma electrode hole aperture value according to each transmission rod telescopic value, to form a plurality of associated data sets of transmission rod telescopic values ​​and plasma electrode hole aperture values; S2. By fitting all the associated data groups, a fitting relationship between the telescopic length of the transmission rod and the aperture of the plasma electrode hole is obtained; S3, preset a target plasma electrode hole diameter value, and reversely calculate the target telescopic value of the transmission rod according to the fitting relationship between the telescopic length of the transmission rod and the plasma electrode hole diameter obtained in step S4; S4. Control the transmission rod to extend or retract to a target extension or retraction value to adjust the aperture of the plasma electrode hole.

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