A microsecond vacuum arc ion source energy spectrum analyzer device and use method

Abstract

The present invention discloses a microsecond vacuum arc ion source energy spectrum analyzer device, including a metal shell, the top of the metal shell has a top opening, the bottom has a concave bottom fixed cylinder with an opening toward the top, and a circular ring is arranged at the opening of the concave bottom fixed cylinder; the inside of the metal shell is sequentially provided with an extraction electrode, a grid, a collector, and a plurality of insulating limit plates separating and fixing the extraction electrode, the grid, and the collector, and a cavity is formed between the plurality of insulating limit plates. This analyzer device adopts a nearly all-metal shell design, which can shield the influence of external electromagnetic fields to the maximum extent. For example, the pulsed high-voltage electric field generated by the discharge of the vacuum arc ion source may affect the diffusion of the plasma and the measurement of the ion flow, and this analyzer device can shield the external electromagnetic field as much as possible to obtain more accurate measurement results.

Description

Technical Field

[0001] The invention relates to an energy spectrum analyzer device and a use method, and in particular to a microsecond vacuum arc ion source energy spectrum analyzer device and a use method. Background Art

[0002] The vacuum arc ion source is a short-pulse high-current ion source used to produce metal / mixed ion beams. It has the characteristics of small size and single-time repeatable discharge. The output ion current intensity reaches hundreds of mA, and it has important application value in neutron generators, ion implanters, etc. The working substance deuterium element is usually stored in the form of metal hydride in the electrode of the vacuum arc ion source, and can be stored for a long time in a vacuum environment. When working, a pulse high voltage is loaded between the cathode and anode of the vacuum arc ion source, which is triggered to generate vacuum arc surface discharge. At the same time, due to the effects of electron bombardment, sputtering, etc., luminous spots are generated on the surface discharge path, which are called cathode spots. The cathode spots contain deuterium and metal ions, and the ions are extracted by the extraction electrode after expansion and diffusion.

[0003] The parameters of the plasma generated by the discharge, such as the electron density, temperature, and ion composition, can be diagnosed through Langmuir probes, spectrometers, and time-of-flight spectra to obtain the performance information of the vacuum arc ion source. In the study of the physical mechanism of the vacuum arc ion source, for example, in the diffusion velocity model of the plasma, Davis et al. used an energy molecular device to measure the kinetic energy of the ions to verify the potential peak theoretical model and found that the experimentally measured ion velocity was low. The possible reason was that the velocities of ions in different charge states differed greatly due to the influence of the vacuum degree. Therefore, it is very important to accurately measure the ion diffusion spectrum. For the measurement of the ion energy spectrum, first, it is necessary to ensure that the vacuum chamber has a sufficiently high vacuum degree to prevent the ion diffusion from being affected by the residual gas; second, the vacuum arc ion source is a short pulse of microseconds, and the energy spectrum measurement needs to be carried out under different bias values ​​of the energy spectrum analyzer. How to ensure that the size, ion composition, and proportion of the ion flow under different pulses are roughly equal, especially when the position of the cathode spot changes during pulse discharge, is a major problem.

[0004] However, there are differences in existing measurement methods and experimental devices, and the ion diffusion rate data obtained vary greatly, resulting in inaccurate measurement data. Summary of the invention

[0005] The technical problem to be solved by the present invention is the inaccurate measurement problem existing in the prior art, and the purpose is to provide a microsecond vacuum arc ion source energy spectrum analyzer device to solve the above problem.

[0006] The present invention is achieved through the following technical solutions:

[0007] A microsecond vacuum arc ion source energy spectrum analyzer device comprises a metal shell, the top of the metal shell is provided with a top opening, the bottom of the metal shell is provided with a concave bottom fixing cylinder with an opening toward the top, and a circular ring is arranged at the opening of the concave bottom fixing cylinder; the interior of the metal shell is provided with an extraction electrode, a grid, a collecting electrode, and a plurality of insulating limit plates separating and fixing the extraction electrode, the grid, and the collecting electrode in sequence from one side of the top opening inward, and a cavity is formed between the plurality of insulating limit plates.

[0008] Furthermore, a microsecond vacuum arc ion source energy spectrometer device is provided, wherein the bottom fixing tube is a cylindrical structure with threads on the outside, and is fixed to the metal shell by screwing the threads; a through hole is provided at the center position of one side of the bottom of the bottom fixing tube, and the through hole protrudes to the outside of the metal shell.

[0009] The bottom fixing cylinder is fixed to the analyzer housing by threads, and the feed line passes through the through hole of the bottom fixing cylinder. The analyzer device of the present invention is similar to a full metal sealing structure as a whole, which can shield the influence of external electromagnetic fields (such as strong electromagnetic fields generated by pulsed high voltage discharge of vacuum arc ion source) to the maximum extent, and obtain more accurate measurement results.

[0010] Furthermore, a microsecond vacuum arc ion source energy spectrum analyzer device is provided, wherein the center of the extraction electrode has a conical opening, the top opening and the extraction electrode form a plasma diffusion zone, and the conical opening at the center of the extraction electrode forms an ion flow emission surface.

[0011] Furthermore, in a microsecond vacuum arc ion source energy spectrum analyzer device, the inner side cross-section of the top opening of the metal shell is a stepped structure, and an insulating limit plate is arranged between the lead-out electrode and the top opening of the metal shell.

[0012] Furthermore, a microsecond vacuum arc ion source energy spectrometer device is provided, wherein the cross-section of the multiple insulating limit plates is a stepped structure; the multiple insulating limit plates are each punched with four through holes, the corresponding through holes are aligned, and fixing screws are fixed in the through holes, and the multiple insulating limit plates are fixed as a whole by the fixing screws.

[0013] The fixing screws are long screws, and multiple insulating limit plates are fixed by the long screws. By embedding the screw caps into the metal shell, the solid relationship between the insulating limit plates, grids, lead electrodes, collectors and the analyzer shell is increased, avoiding looseness during assembly and testing.

[0014] The insulating limit plate is punched with four through holes. When in use, the through holes of each insulating limit plate are aligned, which, on the one hand, serves to allow the feeder to pass through, and on the other hand, is conducive to extracting vacuum and ensuring a high vacuum environment inside the analyzer device.

[0015] Furthermore, in a microsecond vacuum arc ion source energy spectrum analyzer device, both ends of the outer side of the collecting electrode are provided with feeding screws.

[0016] The power supply screw is used to connect the oscilloscope and ensure that the power supply line has good contact.

[0017] Furthermore, in a microsecond vacuum arc ion source energy spectrum analyzer device, the metal shell is cylindrical in shape.

[0018] Furthermore, a microsecond vacuum arc ion source energy spectrum analyzer device is provided, wherein the shape of the opening is a square.

[0019] Furthermore, in a microsecond vacuum arc ion source energy spectrum analyzer device, the number of the grids is three, and the distance between the grids can be adjusted as needed to avoid sparking between the grids.

[0020] A method for using a microsecond vacuum arc ion source energy spectrum analyzer device comprises the following steps:

[0021] S1: placing the entire microsecond vacuum arc ion source energy spectrometer device inside the vacuum chamber;

[0022] S2: A vacuum arc ion source with a diameter of φ = 20 mm is placed in a hollow structure with an opening at the top;

[0023] S3: The metal shell is grounded as a whole;

[0024] S4: Test: The middle grid is connected to a DC power supply, and the voltage amplitude of the DC power supply is adjusted in the range of 0 to 80V; the collector is connected to an oscilloscope; the extraction electrode of the vacuum arc ion source itself is removed, so that the plasma generated by the discharge of the vacuum arc ion source diffuses to the extraction electrode position, and an emission surface is formed at the conical opening in the center of the extraction electrode to obtain an ion flow. The generated ion flow passes through three grids respectively, and finally reaches the collector and is collected; the functional relationship between the grid bias and the collector current is measured, and then the energy spectrum of the ion flow is obtained by conversion.

[0025] The energy spectrum analyzer device in the prior art is mainly for constant current ion sources (such as radio frequency sources, Penning sources, etc.). During measurement, the ion source needs to be kept running to obtain a constant current ion flow, and the bias value of the grid needs to be gradually changed to obtain an IV curve. However, for a vacuum arc ion source with microsecond pulses, a single discharge pulse is ~5μs, and the single pulse time is very short. It is impossible to measure the collection current under different bias values ​​within a single pulse time. If the bias value is changed under different pulses, due to the change in the position of the cathode spot, it is impossible to ensure that the ion flow obtained by the extraction electrode of the ion source itself is consistent with the ion flow obtained under other pulses. In this case, the energy spectrum obtained by the measurement has a large error. The present invention uses a metal shell that is an entire cylindrical shape, and a square opening area is provided on the top. An insulating limit plate and an extraction electrode are arranged on the inner side of the top of the metal shell. During measurement, the extraction electrode of the vacuum arc ion source is removed and placed in the square opening area. The ion source, the square opening area and the extraction electrode form a plasma diffusion and ion flow emission surface. The distance between the cathode spot and the extraction electrode is large enough, and the plasma diffused to the extraction electrode can be considered to have no change in charge state. At this time, the diffusion speed of the ions is no longer affected by the charge state distribution. In addition, the plasma diffused to the metal shell can be guided away in time. The analyzer device simulates the plasma diffusion environment in the vacuum arc ion source, minimizes the difference in the extraction ion flow under different pulses and different cathode spot positions, and makes the measured experimental data more real and reliable.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] 1. The present invention discloses a microsecond vacuum arc ion source energy spectrum analyzer device and a method for using the device. The device adopts a metal shell that is in an overall cylindrical shape, and has a square opening on the top for placing the vacuum arc ion source. An extraction electrode, multiple grids, a collecting electrode, and multiple insulating limit plates are arranged inside the shell. The device ensures a high vacuum environment inside the analyzer to prevent the ion flow from being affected by residual gas, and forms a plasma diffusion structure through the vacuum arc ion source-square opening of the shell-extraction electrode combination, and extracts the ion flow. Such a structural design can greatly reduce the difference in the extraction ion flow caused by different pulses and different cathode spot positions, and can realize the measurement of the energy spectrum of the pulsed vacuum arc ion source under different grid biases, and make the measured experimental data more real and reliable.

[0028] 2. The present invention provides a microsecond vacuum arc ion source energy spectrum analyzer device and a method of use. The middle and edge parts of the disc-shaped insulating limit plate form a stepped structure, forming a mutually embedded convex / concave structure, and three grids, a collecting electrode, etc. are arranged at the convex / concave position. The distance between the grids can be adjusted as needed to avoid sparking between the grids. The insulating limit plate is punched with 4 through holes. When in use, the through holes of each insulating limit plate are aligned. On the one hand, it plays the role of passing the feed line, and on the other hand, it is conducive to extracting vacuum and ensuring a high vacuum environment inside the analyzer device.

[0029] 3. The present invention provides a microsecond vacuum arc ion source energy spectrum analyzer device and a method of use, which adopts a nearly all-metal shell design and can shield the influence of external electromagnetic fields to the maximum extent. For example, the pulsed high-voltage electric field generated by the discharge of the vacuum arc ion source may affect the diffusion of the plasma and the measurement of the ion flow, while the present analyzer device can shield the external electromagnetic field as much as possible to obtain more accurate measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0031] Figure 1 It is a schematic diagram of the structure of the present invention.

[0032] Marks and corresponding parts names in the attached drawings:

[0033] 1-metal shell, 2-lead electrode, 3-insulating limit plate, 4-grid, 5-feeding screw, 6-pressure ring, 7-bottom fixing cylinder, 8-fixing screw, 9-collecting electrode, 10-top opening, 11-through hole, 12-conical opening. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0035] Example

[0036] like Figure 1As shown, a microsecond vacuum arc ion source energy spectrometer device comprises a metal shell 1, wherein the top of the metal shell 1 has a top opening 10, and the bottom has a concave bottom fixed cylinder 7 with an opening toward the top, and a circular ring 6 is arranged at the opening of the concave bottom fixed cylinder 7; the inside of the metal shell 1 is sequentially provided with an extraction electrode 2, a grid 4, a collector 9, and a plurality of insulating limit plates 3 separating and fixing the extraction electrode 2, the grid 4, and the collector 9, from one side of the top opening 10 to the inside, and a cavity is formed between the plurality of insulating limit plates 3. The bottom fixed cylinder 7 is a cylindrical structure with threads on the outside, and is fixed to the metal shell 1 by screwing; a through hole 11 is provided at the center position of one side of the bottom of the bottom fixed cylinder 7, and the through hole 11 protrudes to the outside of the metal shell 1. The center position of the extraction electrode 2 has a conical opening 12, and the top opening 10 and the extraction electrode 2 form a plasma diffusion zone, and the conical opening 12 at the center of the extraction electrode 2 forms an ion flow emission surface. The inner side cross-section of the top opening 10 of the metal shell 1 is a stepped structure, and an insulating limit plate 3 is arranged between the lead-out electrode 2 and the top opening 10 of the metal shell 1. The cross-section of the multiple insulating limit plates 3 is a stepped structure; the multiple insulating limit plates 3 are each punched with four through holes, and the corresponding through holes are aligned, and fixing screws 8 are fixed in the through holes, and the multiple insulating limit plates 3 are fixed as a whole by the fixing screws 8. Feed screws 5 are arranged at both ends of the outer side of the collector 9. The shape of the metal shell 1 is cylindrical. The shape of the opening 10 is square. The number of the grids 4 is three.

[0037] A method for using a microsecond vacuum arc ion source energy spectrum analyzer device comprises the following steps:

[0038] S1: placing the entire microsecond vacuum arc ion source energy spectrometer device inside the vacuum chamber;

[0039] S2: placing a vacuum arc ion source with a diameter of φ=20 mm in the hollow structure with the top opening 10;

[0040] S3: The metal housing 1 is grounded as a whole;

[0041] S4: Test: The middle grid 4 is connected to a DC power supply, and the voltage amplitude of the DC power supply is adjusted in the range of 0 to 80V; the collector 9 is connected to an oscilloscope; the extraction electrode of the vacuum arc ion source itself is removed, so that the plasma generated by the discharge of the vacuum arc ion source diffuses to the position of the extraction electrode 2, and an emission surface is formed at the conical opening 12 in the center of the extraction electrode 2 to obtain an ion flow. The generated ion flow passes through three grids 4 respectively, and finally reaches the collector 9 and is collected; the functional relationship between the bias voltage of the grid 4 and the current of the collector 9 is measured, and then the energy spectrum of the ion flow is obtained by conversion.

[0042] When in use, the entire microsecond vacuum arc ion source energy spectrum analyzer is installed inside the vacuum chamber, and the vacuum arc ion source (diameter φ=20mm) is placed in the square hollow structure on the right (top), and the metal shell is grounded as a whole. During testing, the middle grid 4 is connected to a DC power supply: the voltage amplitude adjustment range is 0-80V, and the collector 9 is connected to an oscilloscope. During testing, the extraction electrode of the vacuum arc ion source itself is removed. Because a constant ion flow cannot be obtained under different pulse discharges and the position of the cathode spot generated under each pulse is not fixed, the plasma generated by the vacuum arc discharge is diffused to the extraction electrode 2 position, and an emission surface is formed at the conical hole in the center of the extraction electrode 2 to obtain the ion flow, thereby reducing the influence of the pulse discharge as much as possible. The generated ion flow passes through the three grids 4 respectively, and finally reaches the collector 9 and is collected. The energy spectrum of the ion flow is obtained by measuring the functional relationship between the bias voltage of the grid 4 and the current of the collector 9, and then converted.

[0043] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A microsecond vacuum arc ion source energy spectrum analyzer device, characterized in that: The invention comprises a metal shell (1), wherein the top of the metal shell (1) has a square opening (10), the bottom of the metal shell (1) has a concave bottom fixing cylinder (7) with an opening facing the top, and a circular ring (6) is arranged at the opening of the concave bottom fixing cylinder (7); the inside of the metal shell (1) is provided with an extraction electrode (2), three grids (4), a collecting electrode (9), and a plurality of separating and fixing the extraction electrode (2), the grids (4), and the collecting electrode (9) in sequence from one side of the top opening (10) to the inside. The invention relates to a plurality of disc-shaped insulating limit plates (3), wherein a cavity is formed between the plurality of disc-shaped insulating limit plates (3); the square opening (10) is used to place a vacuum arc ion source, and during measurement, the extraction electrode of the vacuum arc ion source is removed, and the extraction electrode (2) is placed in the area of ​​the square opening (10); the middle and edge parts of the disc-shaped insulating limit plates (3) form a stepped structure, forming a mutually embedded convex / concave structure, and three grids (4) and a collecting electrode (9) are arranged at the convex / concave positions.

2. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The bottom fixing cylinder (7) is a cylindrical structure with threads on the outside, and is fixed to the metal shell (1) by screwing the threads; a through hole (11) is provided at the center of one side of the bottom of the bottom fixing cylinder (7), and the through hole (11) protrudes to the outside of the metal shell (1).

3. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The extraction electrode (2) has a conical opening (12) at the center thereof, the top opening (10) and the extraction electrode (2) form a plasma diffusion zone, and the conical opening (12) at the center of the extraction electrode (2) forms an ion flow emission surface.

4. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The inner side cross-section of the top opening (10) of the metal shell (1) is a stepped structure, and an insulating limit plate (3) is provided between the lead-out electrode (2) and the top opening (10) of the metal shell (1).

5. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The cross-section of the plurality of insulating limit plates (3) is a stepped structure; the plurality of insulating limit plates (3) are each punched with four through holes, the corresponding through holes are aligned, fixing screws (8) are fixed in the through holes, and the plurality of insulating limit plates (3) are fixed as a whole by the fixing screws (8).

6. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: Feeding screws (5) are provided at both ends of the outer side of the collecting electrode (9).

7. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The metal shell (1) is cylindrical in shape.

8. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The opening (10) is in the shape of a square.

9. The microsecond vacuum arc ion source energy spectrum analyzer device according to claim 1, characterized in that: The number of the grids (4) is three.

10. A method for using the microsecond vacuum arc ion source energy spectrum analyzer device according to any one of claims 1 to 9, characterized in that: The steps include: S1: placing the entire microsecond vacuum arc ion source energy spectrometer device inside the vacuum chamber; S2: A vacuum arc ion source with a diameter of φ=20 mm is placed in the hollow structure with a square opening (10) at the top; S3: The metal casing (1) is grounded as a whole; S4: Test: The three middle grids (4) are connected to a DC power supply, and the voltage amplitude of the DC power supply is adjustable in the range of 0 to 80 V; the collector (9) is connected to an oscilloscope; the extraction electrode of the vacuum arc ion source itself is removed, so that the plasma generated by the discharge of the vacuum arc ion source diffuses to the extraction electrode (2), and an emission surface is formed at the conical opening (12) in the center of the extraction electrode (2) to obtain an ion flow, and the generated ion flow passes through the three grids (4) respectively, and finally reaches the collector (9) and is collected; by measuring the functional relationship between the bias voltage of the grid (4) and the current of the collector (9), the energy spectrum of the ion flow is obtained by conversion.

Images