Large-scale beam monitoring device capable of being used under vacuum and high and low temperature conditions

Abstract

The invention relates to a large beam monitoring device capable of being used under vacuum and high and low temperature conditions, which comprises a spherical vacuum chamber, an electron accelerator beam outlet is connected with the spherical vacuum chamber, a collector is arranged in the spherical vacuum chamber, positive high pressure is applied to the collector, and the outer wall of the spherical vacuum chamber is grounded. An electron beam of the accelerator drifts towards the collector and forms a current signal, the collector is connected with an electrometer outside the spherical vacuum chamber through a cable interface, and the spherical vacuum chamber is further provided with a temperature adjusting device. According to the invention, the influence of geometric asymmetry on electric field distribution is eliminated through the spherical symmetric design, and the measurement uniformity under a large irradiation area is improved; a titanium alloy shell and a multi-layer vacuum sealing structure are adopted, the long-term stability under extreme temperature and high vacuum conditions is ensured, and therefore a high-reliability monitoring tool is provided for spacecraft anti-radiation testing.

Description

Technical Field

[0001] The present invention relates to beam monitoring technology, specifically to a large beam monitoring device that can be used in vacuum and high and low temperature conditions. Background Technology

[0002] Currently, in ground-based simulations of space radiation effects, dose measurement typically employs ionization chamber technology as the core method. Ionization chambers collect the ionized charges generated by high-energy electron beams or radiation particles in a gas, converting the charge quantity into a dose rate or total dose value, thus achieving precise measurement. Traditional ionization chambers often employ cylindrical or flat plate structures, utilizing electric field distribution to guide ionized charges to the collecting electrode. However, these structures are limited in extreme environments (such as temperature ranges from -100℃ to +150℃ and high vacuum conditions). - 5 Pa~10 -7 Significant drawbacks exist at low irradiation levels (Pa): for example, geometric asymmetry leads to uneven electric field distribution in the edge region of a large irradiation area, resulting in insufficient measurement uniformity; poor material thermal stability easily causes electrode spacing deformation, and insufficient sealing performance may lead to signal drift or gas leakage, making it difficult to meet the precise monitoring requirements of large-sized samples such as satellite components. Existing ionization chambers have poor material thermal stability, and at low temperatures, material shrinkage easily causes electrode spacing deformation; insufficient sealing performance may lead to gas leakage or signal drift, affecting long-term reliability. Summary of the Invention

[0003] The purpose of this invention is to address the problems existing in the prior art by providing a large-scale beam monitoring device that can be used in vacuum and high and low temperature conditions, so as to solve the shortcomings of traditional ionization chambers in terms of uniformity, environmental adaptability and parameter compatibility.

[0004] To achieve the above objectives, embodiments of the present invention provide a large beam monitoring device that can be used in vacuum and high / low temperature conditions, including a spherical vacuum chamber, an electron accelerator beam outlet connected to the spherical vacuum chamber, a collecting electrode provided inside the spherical vacuum chamber, a positive high voltage applied to the collecting electrode, the outer wall of the spherical vacuum chamber grounded, the accelerator electron beam drifts toward the collecting electrode and forms a current signal, the collecting electrode is connected to an electrometer outside the spherical vacuum chamber via a cable interface, and the spherical vacuum chamber is also provided with a temperature regulation device.

[0005] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the collecting electrode is a multi-channel collecting electrode, and the electrometer is a multi-channel electrometer.

[0006] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the collecting electrode consists of a base and several metal detection units, the several metal detection units being evenly arranged on the base, and an etched circuit board embedded in the base for applying voltage to the metal detection units and transmitting signals.

[0007] Furthermore, each metal detection unit of the collecting electrode transmits current signals to a multi-channel electrometer outside the spherical vacuum chamber via cables. The multi-channel electrometer acquires the number and signal of each metal detection unit, thereby enabling the monitoring of electron beam fluctuations.

[0008] Furthermore, the base is made of PMMA material, and the metal detection unit is made of copper.

[0009] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the collecting electrode is positioned directly opposite the electron accelerator beam outlet, and an adjustable shielding layer is provided between the collecting electrode and the electron accelerator beam outlet.

[0010] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the spherical vacuum chamber is equipped with a vacuum valve, and the vacuum valve is connected to a vacuum pump through a gas pipeline.

[0011] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high and low temperature conditions, includes a temperature regulation device comprising a metal heat-conducting plate attached to the bottom of the collecting electrode, a metal pipe on the metal heat-conducting plate, and a working fluid inside the metal pipe. The high and low temperature environment inside the spherical vacuum chamber is achieved by adjusting the temperature of the working fluid.

[0012] Furthermore, the metal pipe passes through the spherical vacuum chamber and connects to external temperature control equipment.

[0013] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the outer shell of the spherical vacuum chamber is made of titanium alloy or nickel-iron alloy.

[0014] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high / low temperature conditions, wherein the cable interface is fully sealed with metal. The installation reference is a metal sealing flange that is compatible with the material of the spherical vacuum chamber shell. The flange is fastened and sealed to the chamber body by a metal sealing gasket. A ceramic insulator with a matching coefficient of thermal expansion is embedded in the flange through hole. A metal electrode is sleeved on the ceramic insulator. The two ends of the metal electrode are respectively connected to the internal and external cables and equipment of the chamber. A permanent seal is formed between the ceramic insulator and the metal material by brazing.

[0015] Furthermore, in a specific embodiment, the large beam monitoring device described above, which can be used in vacuum and high and low temperature conditions, employs a composite sealing technology of metal bellows and fluororubber at the opening / joining seal of the spherical vacuum chamber. The metal bellows provides axial or radial deformation compensation to accommodate installation deviations and temperature deformations of the curved surface; the fluororubber serves as the main sealing element, closely adhering to the sealing surface to prevent gas leakage.

[0016] The beneficial effects of this invention are as follows:

[0017] The spherical ionization chamber of this invention eliminates the influence of asymmetry on the electric field distribution through its spherical symmetrical structure design, significantly improving measurement uniformity under large irradiation areas. The combination of a titanium alloy shell and a ceramic insulator results in highly matched coefficients of thermal expansion and minimal deformation. Combined with a metal bellows and fluororubber composite sealing technology, it provides high sealing performance, ensuring long-term stable operation under extreme environments. The ionization chamber features an adjustable gradient aluminum foil shielding layer, which can be mechanically adjusted to adapt to the penetration depth of electron beams of different energies, resulting in small measured dose rate errors. It can quickly interface with existing testing systems via standard interfaces (such as SMA and BNC), significantly reducing modification costs. This invention simultaneously meets the multi-dimensional testing needs of studying the total dose effect of electronic devices under large irradiation areas and material displacement damage. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a large beam monitoring device that can be used in vacuum and high and low temperature conditions, according to a specific embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the collecting electrode in a specific embodiment of the present invention.

[0021] In the diagram, 1. Spherical vacuum chamber, 2. Electron accelerator, 3. Collector electrode, 4. Heat-conducting plate, 5. Vacuum valve, 6. Cable interface, 7. Multi-channel electrometer, 31. Metal detection unit, 32. PMMA base. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0024] The terms “comprising”, “including”, etc., as used herein indicate the presence of the steps, features, operations, or components, but do not preclude the addition of one or more other steps, features, operations, or components.

[0025] This invention relates to a novel large-scale beam monitoring device that can be used under vacuum and high / low temperature conditions. The structure of the device is as follows: Figure 1 As shown, it mainly consists of a vacuum metal chamber, a multi-channel collecting electrode, a multi-channel electrometer, and other parts, and the whole system has the function of monitoring the beam of an electron accelerator under vacuum and high and low temperature conditions.

[0026] In some embodiments, such as Figure 1 As shown, the beam monitoring device includes a spherical vacuum chamber 1. The exit port of the electron accelerator 2 is connected to the spherical vacuum chamber 1. A collecting electrode 3 is provided inside the spherical vacuum chamber 1, and a positive high voltage is applied to the collecting electrode 3. The outer wall of the spherical vacuum chamber 1 is grounded, and a non-uniform electric field exists inside the chamber. The accelerator electron beam drifts towards the collecting electrode and forms a current signal. The collecting electrode 3 is connected to an electrometer 7 outside the spherical vacuum chamber via a cable interface 6. The electrometer 7 is connected to the collecting electrode through a sealed cable interface in the spherical vacuum chamber and has the functions of providing high voltage and signal readout, realizing the monitoring of electron beam fluctuations.

[0027] In some embodiments, the spherical vacuum chamber 1 is made of titanium alloy or nickel-iron alloy stainless steel of a certain thickness, exhibiting small deformation under temperature changes and possessing the function of supporting a large ionization chamber structure and maintaining a vacuum environment. The top of the chamber is connected to the beam outlet of the electron accelerator 2, and the outer side of the metal chamber wall is grounded. Due to the positive high voltage applied to the collecting electrode 3 inside the chamber, a non-uniform electric field exists inside the chamber. The electron beam released by the accelerator will drift towards the collecting electrode and form a current signal. The signal is transmitted outside the chamber and read out by the electrometer 7, realizing the electron beam current monitoring function.

[0028] The spherical vacuum chamber 1 is the main container used to maintain the vacuum environment. It is a large cavity structure made of metal materials such as titanium alloy. Its core function is to provide a stable and sealed space to maintain an ultra-high vacuum state. A ceramic insulator is sleeved on the outside of conductors such as signal transmission wires. Its function is to achieve electrical insulation between the conductors and the metal chamber shell, while ensuring the vacuum seal at the feedthrough point and preventing the vacuum environment inside the vacuum chamber from being disrupted.

[0029] In some embodiments, the spherical vacuum chamber 1 is equipped with a vacuum valve 5, which is connected to an external mechanical vacuum pump via a gas pipeline. During use, the vacuum valve 5 is opened, and the vacuum pump extracts the gas from the chamber, reducing the internal pressure to 10. -5 Pa~10 -7 When the expected vacuum level is reached, vacuum valve 5 closes. High sealing performance is achieved through the sealing structure design of each component on the spherical vacuum chamber 1, ensuring long-term stable operation of the monitoring device under extreme environments.

[0030] In some embodiments, the spherical vacuum chamber 1 is provided with multiple cable interfaces 6 on its lower side. The cable interfaces are fully sealed with metal to prevent gas contamination in the vacuum environment. The collecting electrode inside the spherical vacuum chamber is connected to the cable interface via a signal cable. At the same time, the electrometer outside the spherical vacuum chamber is connected to the cable interface via a signal cable to transmit the current signal generated inside the chamber to the electrometer outside the chamber, thereby realizing the monitoring of the electron beam current.

[0031] The cable structure of the spherical vacuum chamber is a ceramic-insulated, metal-sealed vacuum feeder structure: a metal sealing flange that matches the chamber material is used as the installation reference, and the metal sealing gasket is used to fasten and seal the cable to the chamber. An alumina ceramic insulator with a matching coefficient of thermal expansion is embedded in the flange through hole (multi-channel design to achieve insulation isolation between cables and between cables and the chamber). Copper metal electrodes are sleeved on the ceramic insulator, and the two ends of the electrodes are connected to the cables and equipment inside and outside the chamber, respectively. The ceramic insulator and the metal parts are brazed to form a permanent seal. A protective cover is provided on the outside and an auxiliary fixing plate is provided on the inside, which can ensure the vacuum sealing performance, and the insulation is reliable and the structure is stable.

[0032] In some embodiments, an aluminum experimental platform is provided at the bottom of the spherical vacuum chamber to house the entire beam monitoring device and ensure the stability of the device during the experiment.

[0033] To simulate high and low temperature environments within the chamber, the spherical vacuum chamber is also equipped with a temperature regulation device to control the high and low temperatures within the chamber, thereby simulating extreme environments at different temperatures.

[0034] In some embodiments, the temperature regulating device includes a metal heat-conducting plate 4 disposed close to the collecting electrode 3, and a metal pipe disposed close to the heat-conducting plate 4, the loop of which is filled with a working fluid. The metal pipe can be designed in a U-shape or serpentine shape to ensure sufficient heat transfer on the heat-conducting plate. The metal pipe passes through the chamber wall and is connected to an external temperature control device by welding, and can regulate the temperature of the working fluid. For example, the working fluid can be a cryogenic liquid or a high-temperature liquid. The cryogenic liquid allows the collecting electrode to operate at a low temperature through conduction through the pipe wall and the heat-conducting plate, while the high-temperature liquid allows the collecting electrode to operate at a high temperature through conduction through the pipe wall and the heat-conducting plate, thereby achieving a high and low temperature environment within the spherical vacuum chamber. In some embodiments, the working fluid in the metal pipe is cryogenic silicone oil, and the temperature control range is -30°C to 170°C.

[0035] The collecting electrode 3 inside the spherical vacuum chamber is positioned directly opposite the exit port of the electron accelerator 2. In some embodiments, the collecting electrode 3 is a multi-channel collecting electrode, and correspondingly, the electrometer 7 is also a multi-channel electrometer.

[0036] The collecting electrode 3 consists of a base 32 and several metal detection units 31. The metal detection units 31 are evenly arranged on the base 32, and the base 32 is provided with circuitry for applying voltage to the metal detection units 31 and transmitting signals. The several metal detection units 31 can be arranged in an array on the base 32 to form multi-channel measurement data.

[0037] In some embodiments, the base 32 of the collecting electrode is made of high-temperature resistant PMMA material with high insulation. Several copper metal detection units are arranged in a matrix on the PMMA base. An etched circuit board is embedded in the PMMA base, connected to each metal detection unit, for applying high voltage to the metal detection unit and collecting and transmitting signals. Through specific circuit design, a positive high voltage is applied to each metal detection unit, creating a non-uniform electric field within the spherical vacuum chamber. The electron beam released by the accelerator drifts towards the collecting electrode, where it collects the beam electrons and forms a current signal. The current signal from each metal detection unit is transmitted via cable to cable interface 6, and further to a multi-channel electrometer 7 outside the chamber, enabling multi-channel current signal readout.

[0038] In some embodiments, the collecting electrode is positioned directly opposite the electron accelerator beam exit, and an adjustable shielding layer is disposed between the collecting electrode and the electron accelerator beam exit. By adjusting the thickness of the shielding layer, the penetration depth of electron beams with different energies can be adapted, thereby simulating the space radiation effects under different conditions. For example, the shielding layer can be a gradient aluminum foil adjustable shielding layer, forming aluminum foil shields of different thicknesses. By mechanically adjusting the shielding layer, the electron beam emitted from the electron accelerator beam exit can pass through aluminum foils of different thicknesses, adapting to the penetration depth of electron beams with different energies.

[0039] In some embodiments, a multi-channel electrometer 7, configured to work with the multi-channel collector electrode's multiple current signals, is connected to the multi-channel collector electrode 3 via a sealed cable interface 6 in a spherical vacuum chamber. It provides high voltage to the collector electrode and reads the current signals. The multi-channel electrometer displays the number and current signal of each metal detection unit of the multi-channel collector electrode, enabling monitoring of electron beam fluctuations. It can also plot an overall hotspot map based on signal levels to display the uniformity of the radiation field.

[0040] The large-scale beam monitoring device of this invention significantly improves measurement uniformity through the symmetrical structural design of the spherical ionization chamber, resulting in a marked improvement in beam uniformity compared to traditional structures. The spherical vacuum chamber utilizes a combination of a titanium alloy shell and a ceramic insulator, achieving a highly matched coefficient of thermal expansion and minimal deformation. A composite sealing technology combining metal bellows and fluororubber is incorporated at the chamber's opening / closing / joining seals. The metal bellows provides axial / radial deformation compensation, adapting to installation deviations and temperature deformations on curved surfaces; the fluororubber, as the primary sealing element, adheres tightly to the sealing surface, preventing gas leakage and balancing sealing reliability with assembly flexibility, ensuring long-term stable operation under simulated extreme environments in a vacuum. The temperature control device enables high and low temperature environments within the spherical vacuum chamber, and the ionization chamber features an adjustable gradient aluminum foil shielding layer. Mechanical adjustment adapts to the penetration depth of electron beams of different energies, resulting in minimal measured dose rate error. This invention can quickly interface with existing testing systems via standard interfaces (such as SMA and BNC), significantly reducing modification costs while meeting multi-dimensional testing needs such as total dose effect studies of electronic devices under large irradiation areas and material displacement damage.

[0041] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. Thus, the invention also intends to include such variations and adaptations if they fall within the scope of the claims and their equivalents.

[0042] The above embodiments are merely illustrative examples of the present invention. The present invention may also be implemented in other specific ways or forms without departing from its spirit or essential characteristics. Therefore, the described embodiments should be considered illustrative rather than limiting in any respect. The scope of protection of the present invention should be defined by the claims, and any variations equivalent to the intent and scope of the claims should also be included within the scope of the present invention.

Claims

1. A large beam monitoring device that can be used in vacuum and high / low temperature conditions, characterized in that, It includes a spherical vacuum chamber (1), the electron accelerator (2) beam outlet is connected to the spherical vacuum chamber (1), a collecting electrode (3) is provided in the spherical vacuum chamber (1), a positive high voltage is applied to the collecting electrode (3), the outer wall of the spherical vacuum chamber (1) is grounded, the accelerator electron beam will drift to the collecting electrode and form a current signal, the collecting electrode (3) is connected to the electrometer (7) outside the spherical vacuum chamber through the cable interface (6), and the spherical vacuum chamber (1) is also provided with a temperature regulation device.

2. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The collecting electrode (3) is a multi-channel collecting electrode, and the electrometer (7) is a multi-channel electrometer.

3. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The collecting electrode (3) consists of a base (32) and several metal detection units (31). The several metal detection units (31) are evenly arranged on the base (32). The base (32) has an etched circuit board embedded in it, which is used to apply voltage to the metal detection units (31) and transmit signals.

4. The large beam monitoring device as described in claim 3, which can be used in vacuum and high / low temperature conditions, is characterized in that... Each metal detection unit (31) of the collecting electrode transmits the current signal to the multi-channel electrometer (7) outside the spherical vacuum chamber through a cable. The multi-channel electrometer (7) obtains the number and signal of each metal detection unit (31) to realize the monitoring function of electron beam fluctuation.

5. The large beam monitoring device as described in claim 3, which can be used in vacuum and high / low temperature conditions, is characterized in that... The base (32) of the collecting electrode is made of PMMA, and the metal detection unit (31) is made of copper.

6. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The collecting electrode (3) is positioned directly opposite the exit port of the electron accelerator (2), and an adjustable shielding layer is provided between the collecting electrode and the exit port of the electron accelerator.

7. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The spherical vacuum chamber (1) is equipped with a vacuum valve (5), which is connected to a vacuum pump through a gas pipeline.

8. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The temperature regulation device includes a metal heat-conducting plate (4) attached to the bottom of the collecting electrode. The metal heat-conducting plate (4) is provided with a metal pipe, which is filled with working liquid. The high and low temperature environment inside the spherical vacuum chamber is achieved by adjusting the temperature of the working liquid.

9. The large beam monitoring device as described in claim 8, which can be used in vacuum and high / low temperature conditions, is characterized in that... The metal pipe passes through the spherical vacuum chamber and connects to the external temperature control equipment.

10. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The outer shell of the spherical vacuum chamber (1) is made of titanium alloy or nickel-iron alloy.

11. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The cable interface (6) is fully sealed with metal. The metal sealing flange, which is compatible with the material of the spherical vacuum chamber shell, is used as the installation reference. It is sealed to the chamber by metal sealing gasket. A ceramic insulator with a matching coefficient of thermal expansion is embedded in the flange through hole. The ceramic insulator is fitted with a metal electrode. The two ends of the metal electrode are connected to the cables inside and outside the chamber and the equipment, respectively. The ceramic insulator and the metal material are brazed to form a permanent seal.

12. The large beam monitoring device as described in claim 1, which can be used in vacuum and high / low temperature conditions, is characterized in that... The opening / joining seal of the spherical vacuum chamber (1) adopts a composite sealing technology of metal bellows and fluororubber. The metal bellows provides axial or radial deformation compensation to adapt to the installation deviation and temperature deformation of the curved surface; the fluororubber is used as the main sealing element to fit tightly against the sealing surface and block gas leakage.

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