Helicon wave plasma driven deuterium permeation measuring device and permeation measuring method thereof

Abstract

The invention discloses a helicon wave plasma-driven deuterium permeation measurement device. The device comprises a plasma generation system and a permeation measurement system, the plasma generation system comprises an external magnetic field arranged on the upstream vacuum chamber; deuterium is introduced into one end of the upstream vacuum chamber, and the other end is connected with a downstream vacuum chamber; one end of the downstream vacuum chamber is located in the upstream vacuum chamber and defines a sample to be detected, and the other end is connected with a residual gas analyzer; the plasma generation system applies a magnetic field outside the upstream vacuum chamber through an axial magnetic field unit, generates helicon wave plasma, and enables the helicon wave plasma to be propagated to the surface of the to-be-detected sample in the axial direction and permeate the to-be-detected sample; and the penetration measurement system is used for detecting deuterium penetrating through the to-be-detected sample. The invention discloses a helicon wave plasma driven deuterium permeation measuring device and a permeation measuring method thereof, which can improve the deuterium permeation driving capability and realize stable steady-state deuterium permeation measurement.

Description

Technical Field

[0001] This invention relates to the field of hydrogen isotope permeation testing technology, specifically to a helical wave plasma-driven deuterium permeation measuring device and its permeation measurement method. Background Technology

[0002] In fusion devices and high-power plasma devices, refractory metals such as tungsten are often used as first-wall and divertor materials. Under hydrogen isotope plasma irradiation, these metals exhibit significant permeation, retention, and blistering phenomena. The permeation behavior of hydrogen isotopes in these materials not only affects fuel cycle efficiency but is also closely related to the service life and safety of structural materials. Due to limitations in experimental conditions and operating time for large-scale fusion devices, deuterium permeation measurements cannot be conducted flexibly and conveniently. Therefore, developing experimental devices to measure deuterium permeation in fusion materials under simulated fusion plasma irradiation conditions is of great significance.

[0003] Currently, the main methods for measuring deuterium permeation include electrochemical methods, gas-phase driven permeation, and plasma-driven permeation. Electrochemical methods are less commonly used due to their susceptibility to external influences, poor repeatability of experimental conditions, and significant discrepancies between permeation experimental parameters and conditions and the actual application conditions of the material. Gas-phase driven permeation, on the other hand, involves gas permeating from the high-pressure side to the low-pressure side under the influence of a pressure difference across the sample. While it can effectively simulate the permeation process of gaseous hydrogen isotopes, it cannot simulate the complex plasma environment of a fusion reactor.

[0004] In summary, the existing technology has the following problems: 1. Limited Plasma Density and Particle Flux: Existing plasma sources are mostly conventional radio frequency, microwave, or thermionic discharge forms, which have limited plasma density and particle flux under low-pressure conditions, making it difficult to form high-flux, stable hydrogen isotope injection boundary conditions on the sample surface. This limitation results in: insufficient permeation driving force; weak permeation signal, and limited measurement sensitivity. 2. The plasma interaction mode differs significantly from actual fusion operating conditions: Existing plasma technologies primarily involve localized discharges within cavities. Their spatial distribution and propagation characteristics differ significantly from the plasma propagating along magnetic field lines in fusion devices, making it difficult to realistically simulate the service conditions of fusion materials in a plasma environment. Therefore, the experimental representativeness and extrapolation of such devices are somewhat limited when used for fusion-related material research.

[0005] 3. Insufficient plasma stability hinders steady-state permeation measurements: Due to the lack of magnetic field confinement and wave mode control, existing plasma sources are prone to discharge instability and density fluctuations under low pressure and high power conditions, making long-term continuous operation difficult. This makes it challenging to perform steady-state hydrogen isotope permeation measurements with current technology, affecting the accuracy of quantitative analysis of permeation behavior. Summary of the Invention

[0006] This invention overcomes the shortcomings of the prior art and provides a helical wave plasma-driven deuterium permeation measurement device and its permeation measurement method. The plasma-driven permeation measurement device significantly improves the deuterium permeation driving capability, realizes stable steady-state deuterium permeation measurement, can simulate the service environment of fusion materials, and balances technical performance improvement with controllable device cost.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a deuterium permeation measurement device driven by helical wave plasma, comprising: a plasma generation system, and a permeation measurement system for detecting the permeation state of the plasma generation system; The plasma generation system includes an upstream vacuum chamber, an external magnetic field is installed on the upstream vacuum chamber and deuterium is introduced, the other end of the upstream vacuum chamber is connected to a downstream vacuum chamber, one end of the downstream vacuum chamber is located in the upstream vacuum chamber and contains the sample to be tested, and the other end of the downstream vacuum chamber is connected to a residual gas analyzer. The plasma generation system applies a magnetic field outside the upstream vacuum chamber through the axial magnetic field unit, generates helical wave plasma, and propagates the helical wave plasma along the axis to the surface of the sample to drive the injection and permeation of deuterium in the sample. The permeation measurement system is used to detect deuterium that permeates through the sample being tested.

[0008] In a preferred embodiment of the present invention, the plasma generation system further includes an axial magnetic field unit disposed outside the upstream vacuum chamber, a radio frequency antenna unit and a gas supply unit connected to one end of the upstream vacuum chamber, and the other end of the upstream vacuum chamber is connected to a downstream vacuum chamber and an upstream vacuum unit. The permeation measurement system also includes a downstream vacuum chamber connected to a residual gas analyzer, and the downstream vacuum unit and calibration unit are also connected to the downstream vacuum chamber.

[0009] In a preferred embodiment of the present invention, the radio frequency antenna unit includes: a quartz tube disposed in the upstream vacuum chamber, and a spiral wave plasma antenna disposed around the outside of the quartz tube; the spiral wave plasma antenna is electrically connected to the radio frequency power supply through a matching device, and the radio frequency antenna unit is used to excite the formation of spiral wave plasma under the action of an external axial magnetic field.

[0010] In a preferred embodiment of the present invention, the gas supply unit includes: an upstream deuterium gas supply unit, which is connected to a quartz tube to supply gas to the quartz tube; and a mass flow meter is also provided on the pipeline connecting the upstream deuterium gas supply unit and the quartz tube, which is used to regulate the gas supply flow rate of deuterium.

[0011] In a preferred embodiment of the present invention, the axial magnetic field unit includes: an electromagnetic coil surrounding an upstream vacuum chamber, and a DC power supply providing DC power to the electromagnetic coil, for forming an axial magnetic field in the plasma generation region to support the formation and propagation of helical wave plasma.

[0012] In a preferred embodiment of the present invention, the upstream vacuum unit includes: an upstream gate valve disposed at the bottom of the upstream vacuum chamber, and an upstream molecular pump and an upstream mechanical pump connected in sequence, for evacuating the upstream vacuum chamber.

[0013] In a preferred embodiment of the present invention, the permeation measurement system further includes a sample clamping unit disposed at the front end of the downstream vacuum chamber; The residual gas analyzer is located at the top of the downstream vacuum chamber, and the calibration unit is located at the tail end of the downstream vacuum chamber.

[0014] In a preferred embodiment of the present invention, the sample clamping unit includes a sample holder mounted at the front end of the downstream vacuum chamber via a flange. The sample holder is used to fix the sample to be tested, so that the helical wave plasma acts directly on the sample surface of the sample to be tested along the axial direction.

[0015] In a preferred embodiment of the present invention, the calibration unit includes a calibration gas cylinder for providing high-purity deuterium gas, a standard leak hole connected by a stainless steel gas pipe, and a shut-off valve disposed therebetween. The calibration unit is connected to a downstream vacuum chamber and is used to calibrate the permeation measurement signal. And / or, The downstream vacuum unit includes a downstream gate valve located at the bottom of the downstream vacuum chamber. One end of the downstream gate valve is connected to the downstream vacuum chamber, and the other end of the downstream gate valve is connected to the downstream molecular pump and the downstream mechanical pump in sequence. The downstream vacuum unit is used to evacuate the downstream vacuum chamber.

[0016] In a preferred embodiment of the present invention, a permeation measurement method for a helical wave plasma-driven deuterium permeation measurement device includes a sample installation stage, a device vacuum preparation stage, a permeation measurement system calibration stage, and a permeation measurement stage. The sample installation stage includes the following steps: after removing the sample holder, install the sample to be tested into the sample holding unit; The vacuum preparation stage of the device includes the following steps: close the upstream gate valve, downstream gate valve, and shut-off valve; start the upstream and downstream mechanical pumps; after a certain period of time, open the upstream and downstream gate valves; when the readings of the upstream and downstream vacuum gauges drop below 10 Pa, open the shut-off valve, upstream molecular pump, and downstream molecular pump; wait until the downstream vacuum gauge reading is less than 10 Pa. -6 When Pa, the calibration of the permeability measurement system begins; The calibration phase of the permeation measurement system includes the following steps: turn on the residual gas analyzer to detect the residual gas in the downstream vacuum chamber, and perform calibration after the displayed value stabilizes; The permeation measurement stage includes the following steps: performing helical wave plasma discharge in a plasma generation system and conducting an irradiation permeation experiment on the sample to be tested.

[0017] This invention addresses the deficiencies in the technical background, and the beneficial technical effects of this invention are: A helical wave plasma-driven deuterium permeation measurement device and its permeation measurement method are disclosed. The plasma-driven permeation measurement device significantly improves the deuterium permeation driving capability, realizes stable steady-state deuterium permeation measurement, can simulate the service environment of fusion materials, and balances technical performance improvement with controllable device cost.

[0018] This invention increases plasma density and particle flux by exciting helical wave plasma under an external magnetic field; it constructs an irradiation environment that more closely resembles fusion conditions by utilizing the axial propagation and stable existence characteristics of helical wave plasma; and it expands the operating range of plasma penetration experiments while ensuring a relatively simple device structure. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a schematic diagram of a spiral wave plasma-driven deuterium permeation measurement device in a preferred embodiment of the present invention; Figure 2 The schematic diagram of the plasma generation system in the spiral wave plasma-driven deuterium permeation measurement device in a preferred embodiment of the present invention is shown below. Figure 3 This is a schematic diagram of the permeation measurement system in the spiral wave plasma-driven deuterium permeation measurement device in a preferred embodiment of the present invention; The components include: 1. Plasma generation system; 2. Permeation measurement system; 3. Radio frequency antenna unit; 4. Gas supply unit; 5. Axial magnetic field unit; 6. Upstream vacuum unit; 7. Sample clamping unit; 8. Residual gas analyzer; 9. Downstream vacuum unit; 10. Calibration unit; 11. Helical wave plasma antenna; 12. Quartz tube; 13. Radio frequency power supply; 14. Matching unit; 15. Mass flow meter; 16. Upstream deuterium gas supply unit; 17. DC power supply; 18. Electromagnetic coil; 19. Upstream mechanical pump; 20. Upstream molecular pump; 21. Upstream gate valve; 22. Upstream vacuum chamber; 23. Upstream vacuum gauge; 24. Sample holder; 25. Sample to be tested; 26. Downstream vacuum chamber; 27. Downstream gate valve; 28. Downstream molecular pump; 29. ​​Downstream mechanical pump; 30. Calibration gas cylinder; 31. Standard leak; 32. Shut-off valve; 33. Downstream vacuum gauge. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams, which are only used to illustrate the basic structure of the present invention and therefore only show the components relevant to the present invention.

[0022] It should be noted that if directional indicators (such as up, down, bottom, top, etc.) are involved in the embodiments of the present invention, these directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature. Unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0023] Example 1, as Figures 1-3 As shown, a helical wave plasma-driven deuterium permeation measurement device includes: a plasma generation system 1, and a permeation measurement system 2 for detecting the permeation state of the plasma generation system 1.

[0024] The plasma generation system 1 includes an upstream vacuum chamber 22. An axial magnetic field unit 5 is installed outside the upstream vacuum chamber 22 to provide an external magnetic field. One end of the upstream vacuum chamber 22 is connected to a radio frequency antenna unit 3 and a gas supply unit 4, which introduces deuterium into the upstream vacuum chamber 22. The other end of the upstream vacuum chamber 22 is connected to a downstream vacuum chamber 26 and the upstream vacuum unit 6. Further, one end of the downstream vacuum chamber 26 is located within the upstream vacuum chamber 22 and defines the sample 25 to be tested. The other end of the downstream vacuum chamber 26 is connected to a residual gas analyzer 8. The plasma generation system 1 applies an external magnetic field to the upstream vacuum chamber 22 through the axial magnetic field unit 5, generating helical wave plasma. This helical wave plasma propagates axially to the surface of the sample 25 to drive the injection and permeation of deuterium into the sample 25.

[0025] The permeation measurement system 2 includes a downstream vacuum chamber 26 connected to a residual gas analyzer 8, and a downstream vacuum unit 9 and a calibration unit 10. The permeation measurement system 2 is used to detect deuterium that permeates through the sample 25 to be tested.

[0026] In Embodiment 2, based on Embodiment 1, the radio frequency antenna unit 3 includes: a quartz tube 12 disposed in the upstream vacuum chamber 22, and a spiral wave plasma antenna 11 surrounding the outside of the quartz tube 12; the spiral wave plasma antenna 11 is electrically connected to the radio frequency power supply 13 through a matching device 14, and the radio frequency antenna unit 3 is used to excite the formation of spiral wave plasma under the action of an external axial magnetic field.

[0027] Specifically, the gas supply unit 4 includes an upstream deuterium gas supply unit 16, which is connected to the quartz tube 12 to supply gas to the quartz tube 12. Furthermore, a mass flow meter 15 is installed on the pipeline connecting the upstream deuterium gas supply unit 16 and the quartz tube 12, and the mass flow meter 15 is used to regulate the deuterium gas supply flow rate. Further, the pipeline connecting the upstream deuterium gas supply unit 16 and the quartz tube 12 is made of stainless steel, and the upstream deuterium gas supply unit 16 is connected to the upstream vacuum chamber 22 through the stainless steel pipeline to provide working gas to the plasma generation area.

[0028] Specifically, the axial magnetic field unit 5 includes an electromagnetic coil 18 surrounding the exterior of the upstream vacuum chamber 22, and a DC power supply 17 providing DC power to the electromagnetic coil 18, for forming an axial magnetic field in the plasma generation region to support the formation and propagation of helical wave plasma.

[0029] Specifically, the upstream vacuum unit 6 includes an upstream gate valve 21 located at the bottom of the upstream vacuum chamber 22, and an upstream molecular pump 20 and an upstream mechanical pump 19 connected in sequence, for evacuating the upstream vacuum chamber 22. Specifically, an upstream vacuum gauge 23 is located at the top of the upstream vacuum chamber 22 for real-time monitoring of the vacuum level of the upstream vacuum unit 6.

[0030] Specifically, the permeation measurement system 2 also includes a sample clamping unit 7 disposed at the front end of the downstream vacuum chamber 26; a residual gas analyzer 8 disposed at the top of the downstream vacuum chamber 26; and a calibration unit 10 disposed at the tail end of the downstream vacuum chamber 26. Further, the sample clamping unit 7 includes a sample holder 24 mounted to the front end of the downstream vacuum chamber 26 via a flange. The sample holder 24 is used to fix the sample 25 to be tested, allowing the helical wave plasma to act directly on the sample surface of the sample 25 along the axial direction.

[0031] Specifically, the calibration unit 10 includes a calibration gas cylinder 30 for providing high-purity deuterium gas, a standard leak 31 connected by a stainless steel gas pipe, and a shut-off valve 32 disposed therebetween. The calibration unit 10 is connected to the downstream vacuum chamber 26 and is used to calibrate the permeation measurement signal.

[0032] Specifically, the downstream vacuum unit 9 includes a downstream gate valve 27 disposed at the bottom of the downstream vacuum chamber 26. One end of the downstream gate valve 27 is connected to the downstream vacuum chamber 26, and the other end of the downstream gate valve 27 is connected to the downstream molecular pump 28 and the downstream mechanical pump 29 in sequence. Specifically, the downstream vacuum unit 9 is used to evacuate the downstream vacuum chamber 26. Specifically, a downstream vacuum gauge 33 is also installed at the top of the downstream vacuum chamber 26 to monitor the vacuum level of the downstream vacuum chamber 26 in real time.

[0033] Example 3: In a specific embodiment, a deuterium permeation test was performed on a circular tungsten sheet sample with a diameter of 20 mm and a thickness of 5 mm using a 13.56 MHz radio frequency power supply at a power of 4 kW and deuterium gas as the working gas.

[0034] The details are as follows: A permeation measurement method using a helical wave plasma-driven deuterium permeation measurement device, implemented using the helical wave plasma-driven deuterium permeation measurement device of Example 1 or Example 2, includes, in sequence, a sample installation stage, a device vacuum preparation stage, a calibration stage of the permeation measurement system 2, and a permeation measurement stage. The sample installation stage includes the following steps: after removing the sample holder 24 (using the sample holder flange), the sample to be tested 25 is installed in the sample holder unit 7, and the device enters the vacuum preparation stage.

[0035] The vacuum preparation stage of the device includes the following steps: close the upstream gate valve 21, the downstream gate valve 27, and the shut-off valve 32; start the upstream mechanical pump 19 and the downstream mechanical pump 29; after 10 minutes, open the upstream gate valve 21 and the downstream gate valve 27; when the readings of the upstream vacuum gauge 23 and the downstream vacuum gauge 33 drop below 10 Pa, open the shut-off valve 32, the upstream molecular pump 20, and the downstream molecular pump 28; wait until the readings of both the upstream vacuum gauge 23 and the downstream vacuum gauge 33 are less than 10 Pa. -6 When Pa, the calibration stage of the permeability measurement system 2 begins.

[0036] The calibration phase of the permeation measurement system 2 includes the following steps: Turning on the residual gas analyzer 8 to detect the residual gas in the downstream vacuum chamber 26, and waiting for the background deuterium partial pressure P... D0 After stabilization, calibration was performed to establish the detection signal of the residual gas analyzer 8 (i.e., the partial pressure of deuterium P). D The quantitative relationship between the leakage rate L of the standard leak 31 (unit: Pa).

[0037] Specifically, first, the calibration gas cylinder 30 is opened. Based on the calibration curve of the standard leak 31 (a standard leak 31 is a device with a specific leakage rate under certain pressure difference and operating temperature conditions. The calibration curve of the standard leak 31 is provided by the manufacturer of the standard leak 31 and is data specific to the standard leak 31 product itself), multiple calibration points are selected. First, the outlet pressure P1 of the calibration gas cylinder 30 is adjusted to the first calibration point. Gas enters the downstream vacuum chamber 26 through the standard leak 31 at this pressure, using the standard leak rate L1 of the standard leak 31. The residual gas analyzer 8 then measures the deuterium partial pressure P... D1 After stabilization, adjust the outlet pressure of calibration cylinder 30 to the next calibration point; gradually increase the calibration point pressure and repeat this process until the residual gas analyzer 8 completes the calibration of all deuterium partial pressures P. D Measurement. The residual gas analyzer 8 measured the partial pressure of deuterium P. Di Leakage rate L compared to standard leak 31 i The relationship is linear. Multiple calibration points (P) Di ,L i Substituting into the linear fitting model y=Kx (subtracting the background deuterium partial pressure P) D0 The slope is calculated using the least squares method, and this slope is the calibration coefficient K. The calibration curve for the permeation measurement system can then be obtained: L = KP D Finally, close the calibration cylinder 30 and the shut-off valve 32, and wait until the reading of the downstream vacuum gauge 33 is less than 10. -6 Only after the background deuterium partial pressure measured by the residual gas analyzer 8 has stabilized can the deuterium permeability measurement of the sample 25 be started.

[0038] The permeation measurement stage includes the following steps: Helical wave plasma discharge is performed in plasma generation system 1, and an irradiation permeation experiment is conducted on the sample 25 to be tested. The measurement is completed when the readings of both the upstream vacuum chamber 22 and the downstream vacuum gauge 33 are less than 10. -6 At a certain pressure (Pa), the residual gas analyzer 8 is turned on. After the deuterium component in the residual gas analyzer 8 stabilizes, the irradiation permeation experiment begins. First, the gas cylinder of the upstream deuterium supply unit 16 is turned on, and the deuterium flow rate is controlled by the mass flow meter 15, thereby controlling the deuterium pressure in the upstream vacuum chamber 22. Then, the DC power supply 17 is turned on and the current is adjusted to 100A. Subsequently, the RF power supply 13 is turned on and the power is adjusted to 100W. At the same time, the matching device 14 is adjusted to complete the helical wave plasma ignition. Then, the RF power supply 13 and the matching device 14 are adjusted simultaneously. While maintaining the stability of the helical wave plasma, the power is increased to 4kW. At this time, a significant deuterium plasma beam will be observed bombarding the sample 25 under test, and the deuterium partial pressure in the residual gas analyzer 8 will rise. After a period of time, the deuterium permeation spectrum will be displayed. This completes one deuterium permeation test of a tungsten sheet sample.

[0039] Specifically, the downstream vacuum chamber 26 and the upstream vacuum chamber 22 of the device are combined to form an irradiation chamber (upstream vacuum chamber 22): a spiral wave plasma source is placed at one end of the upstream vacuum chamber 22, deuterium gas is introduced and the plasma is excited to irradiate one side of the sample 25 to be tested. The core function of this region is to generate high-energy deuterium ions / atoms and inject them into the surface of the sample 25 to be tested.

[0040] Specifically, the downstream vacuum chamber 26 serves as a permeation chamber: located on the other side of the sample 25, it maintains an ultra-high vacuum state (<10). -6 Pa) is used to quickly remove deuterium atoms that have permeated from the sample 25, preventing the reverse diffusion of downstream deuterium and ensuring the unidirectionality of the permeation process.

[0041] Specifically, the sample to be tested 25 is sealed and embedded in the downstream vacuum chamber 26 by the sample holder 24 (sample holder flange): ensuring that there is no direct air leakage in the cavities on both sides of the sample to be tested 25, and avoiding interference from background leakage on the downstream detection signal.

[0042] Furthermore, before entering the permeation measurement stage, after the calibration operation of the previously implemented "calibration stage of permeation measurement system 2" is completed, the gas released from the calibration gas cylinder 30 into the downstream vacuum chamber 26 is removed using conventional methods in the existing technology, and the system is restored to the state of "device vacuum preparation stage" before the test operation of "permeation measurement stage" is started.

[0043] Working principle: like Figures 1-3As shown, a helical wave plasma-driven deuterium permeation measurement device and its measurement method are disclosed. The plasma-driven permeation measurement device significantly improves the deuterium permeation driving capability, achieves stable steady-state deuterium permeation measurement, can simulate the service environment of fusion materials, and balances technical performance improvement with controllable device cost. This invention increases plasma density and particle flux by exciting helical wave plasma under an external magnetic field; utilizes the axial propagation and stable existence characteristics of helical wave plasma to construct an irradiation environment closer to fusion operating conditions; and expands the operating range of plasma permeation experiments while maintaining a relatively simple device structure.

[0044] First, it significantly improves the deuterium permeation driving capability and measurement sensitivity: due to the high density and high particle flux of helical wave plasma, under the same gas pressure and input power conditions, stronger deuterium injection conditions can be formed on the sample surface, thereby: increasing the deuterium permeation rate; and enhancing the permeation signal intensity.

[0045] Second, to achieve stable steady-state deuterium permeation measurement: Under the action of an external magnetic field, the spiral wave plasma can be stably maintained under low pressure conditions, enabling the device to operate continuously for a long time, which is beneficial for: obtaining steady-state permeation data; improving the accuracy of permeation parameter inversion; and reducing random errors in experimental results.

[0046] Third, it more realistically simulates the service environment of fusion materials: In this invention, the plasma propagates along the axis and acts directly on the sample surface. Its plasma structure and action mode are closer to the plasma environment that the materials in the fusion device are subjected to, thereby improving the applicability and reference value of the experimental results in fusion material research.

[0047] Fourth, it balances improved technical performance with controllable device costs: Compared to complex ion beam implantation systems, this invention uses direct plasma irradiation, which significantly improves plasma parameters while avoiding the problems of complex structure and high cost associated with high-energy ion beam systems, thus having good engineering feasibility.

[0048] The above specific embodiments are specific support for the concept proposed in this invention, and should not be used to limit the scope of protection of this invention. Any equivalent changes or modifications made on the basis of this technical solution in accordance with the technical concept proposed in this invention shall still fall within the scope of protection of this invention.

Claims

1. A helicon plasma driven deuterium permeation measurement apparatus, characterized by, The application relates to a plasma generation system (1) and a permeation measurement system (2) for detecting the permeation state of the plasma generation system (1). The plasma generation system (1) comprises an upstream vacuum chamber (22) provided with an external magnetic field and deuterium gas; the other end of the upstream vacuum chamber (22) is connected with a downstream vacuum chamber (26) which is located in the upstream vacuum chamber (22) and defines a sample (25) to be detected; the other end of the downstream vacuum chamber (26) is connected with a residual gas analyzer (8). The plasma generation system (1) applies a magnetic field to the upstream vacuum chamber (22) through an axial magnetic field unit (5) to generate a helicon wave plasma, and makes the helicon wave plasma propagate along the axis to the surface of the sample (25) to be detected to drive the injection and permeation of deuterium in the sample (25) to be detected. The permeation measurement system (2) is used for detecting the deuterium permeating through the sample (25) to be detected. The plasma generation system (1) further comprises an axial magnetic field unit (5) arranged outside the upstream vacuum chamber (22), an RF antenna unit (3) and a gas supply unit (4) connected with one end of the upstream vacuum chamber (22), and a downstream vacuum chamber (26), an upstream vacuum unit (6) connected with the other end of the upstream vacuum chamber (22).

2. The helicon plasma driven deuterium permeation measurement apparatus of claim 1, wherein: The permeation measurement system (2) further comprises that one end of the downstream vacuum chamber (26) connected with the residual gas analyzer (8) is further connected with a downstream vacuum unit (9) and a calibration unit (10). The RF antenna unit (3) comprises a quartz tube (12) arranged in the upstream vacuum chamber (22) and a helicon wave plasma antenna (11) arranged outside the quartz tube (12); the helicon wave plasma antenna (11) is electrically connected with an RF power supply (13) through a matcher (14); and the RF antenna unit (3) is used for exciting the formation of the helicon wave plasma under the action of the external axial magnetic field.

3. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 2, wherein: The gas supply unit (4) comprises an upstream deuterium gas supply unit (16) connected with the quartz tube (12) to supply the quartz tube (12) with deuterium gas; and a mass flow meter (15) is further arranged on the pipeline connected with the quartz tube (12) of the upstream deuterium gas supply unit (16), and the mass flow meter (15) is used for adjusting the supply flow of the deuterium gas.

4. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 2, wherein: The axial magnetic field unit (5) comprises an electromagnetic coil (18) arranged outside the upstream vacuum chamber (22) and a DC power supply (17) for providing DC power for the electromagnetic coil (18), which is used for forming an axial magnetic field in the plasma generation area to support the formation and propagation of the helicon wave plasma.

5. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 3, wherein: The upstream vacuum unit (6) comprises an upstream gate valve (21) arranged at the bottom of the upstream vacuum chamber (22) and an upstream molecular pump (20) and an upstream mechanical pump (19) connected in sequence, which are used for vacuumizing the upstream vacuum chamber (22).

6. The helicon wave plasma driven deuterium permeation measurement device of claim 4, wherein: ​ 7. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 6, wherein: The permeation measurement system (2) further comprises a sample clamping unit (7) arranged at the front end of the downstream vacuum chamber (26); A residual gas analyzer (8) is arranged at the top of the downstream vacuum chamber (26), and a calibration unit (10) is arranged at the tail end of the downstream vacuum chamber (26).

8. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 7, wherein: The sample clamping unit (7) comprises a sample holder (24) mounted at the front end of the downstream vacuum chamber (26) by flange, and the sample holder (24) is used for fixing the sample to be measured (25), so that the helicon plasma directly acts on the sample surface of the sample to be measured (25) in the axial direction.

9. The helicon wave plasma driven deuterium permeation measurement apparatus of claim 8, wherein: The calibration unit (10) comprises a calibration gas cylinder (30) for providing high-purity deuterium gas, a standard leak hole (31) connected by a stainless steel gas pipe, and a stop valve (32) arranged therebetween, and the calibration unit (10) is in communication with the downstream vacuum chamber (26) for calibrating the permeation measurement signal; And / or, The downstream vacuum unit (9) comprises a downstream gate valve (27) arranged at the bottom of the downstream vacuum chamber (26), one end of the downstream gate valve (27) is connected with the downstream vacuum chamber (26), and the other end of the downstream gate valve (27) is sequentially connected with a downstream molecular pump (28) and a downstream mechanical pump (29); The downstream vacuum unit (9) is used for vacuumizing the downstream vacuum chamber (26).

10. A method of permeation measurement of a deuterium permeation measurement device driven by a helicon plasma, characterized by: The helicon plasma driven deuterium permeation measurement device of claim 8 or claim 9 is realized, comprising a sample installation stage, a device vacuum preparation stage, a calibration stage of the permeation measurement system (2), and a permeation measurement stage; The sample installation stage comprises the following steps: installing the sample to be measured (25) in the sample clamping unit (7) by removing the sample holder (24); The device vacuum preparation stage, including the following steps: close upstream gate valve (21), downstream gate valve (27), stop valve (32), open upstream mechanical pump (19), downstream mechanical pump (29), open upstream gate valve (21), downstream gate valve (27) after a period of time, when the upstream vacuum gauge (23) and downstream vacuum gauge (33) reading drops to 10 Pa or less, open stop valve (32), upstream molecular pump (20) and downstream molecular pump (28), when the downstream vacuum gauge (33) reading is less than 10 -6 Pa, start the calibration of the permeation measurement system; The calibration stage of the permeation measurement system (2) comprises the following steps: starting the residual gas analyzer (8), detecting the residual gas of the downstream vacuum chamber (26), and calibrating after the number is stable; The permeation measurement stage comprises the following steps: helicon plasma discharge is carried out in the plasma generation system (1), and the sample to be measured (25) is irradiated for permeation experiment.

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