Carbon film cleaning system

Abstract

This application provides a carbon film cleaning system applicable to the field of particle detection technology. The carbon film cleaning system includes: a cleaning execution device comprising: a vacuum chamber configured to provide a vacuum environment; an ion cleaning module disposed in the vacuum chamber, configured to use an ion beam to clean contaminants adsorbed on the surface of the carbon film to be cleaned; a laser cleaning module disposed in the vacuum chamber, configured to use a laser beam to clean volatile substances adsorbed on the surface of the carbon film to be cleaned; and a control device communicatively connected to the cleaning execution device, configured to control the working sequence of the ion cleaning module and the laser cleaning module, such that the ion cleaning module operates before the laser cleaning module. This not only achieves the removal of different types of contaminants but also reduces the risk of over-cleaning or structural damage to the carbon film to be cleaned. While ensuring the effective thickness of the carbon film to be cleaned remains within a predetermined thickness range, this system improves cleaning efficiency and purity, thereby enhancing the efficiency of space particle detection.

Description

Technical Field

[0001] This application relates to the field of space particle detection technology, and more specifically, to a carbon film cleaning system. Background Technology

[0002] With the widespread application of carbon films in space exploration, research on their properties is constantly deepening. Among related technologies, space particle detection is achieved through charge exchange and secondary electron emission effects generated by the interaction between space particles and carbon films.

[0003] Among related technologies, space particle detection has relatively low efficiency. Summary of the Invention

[0004] In view of this, embodiments of this application provide a carbon film cleaning system.

[0005] One aspect of this application provides a carbon film cleaning system, including: a cleaning execution device, the cleaning execution device comprising: a vacuum chamber configured to provide a vacuum environment; an ion cleaning module disposed in the vacuum chamber and configured to use an ion beam to clean contaminants adsorbed on the surface of the carbon film to be cleaned; a laser cleaning module disposed in the vacuum chamber and configured to use a laser beam to clean volatile substances adsorbed on the surface of the carbon film to be cleaned; and a control device communicatively connected to the cleaning execution device and configured to control the working sequence of the ion cleaning module and the laser cleaning module, such that the ion cleaning module works before the laser cleaning module.

[0006] According to an embodiment of this application, the cleaning execution device further includes: a thickness measurement module disposed in a vacuum cavity, configured to detect the electrical signal before and after the interaction between the ion beam and the carbon film to be cleaned, and to determine the effective thickness of the carbon film to be cleaned after being cleaned by the ion cleaning module based on the electrical signal before and after the interaction between the ion beam and the carbon film to be cleaned; and a control device communicatively connected to the thickness measurement module, configured to control the working state of the ion cleaning module based on the effective thickness.

[0007] According to an embodiment of this application, a thickness measurement module includes: a first detector disposed on one side of the carbon film to be cleaned relative to the incident direction of the ion beam, configured to provide a start electrical signal by detecting secondary electrons generated by the ion beam bombarding the carbon film to be cleaned; a second detector disposed on one side of the carbon film to be cleaned relative to the exit direction of the ion beam, configured to provide a stop electrical signal by detecting ions after the ion beam passes through the carbon film to be cleaned; a first signal processing unit configured to determine the effective thickness of the carbon film to be cleaned by the ion cleaning module based on the start electrical signal and the stop electrical signal; and / or a control device configured to control the ion cleaning module to suspend operation when the variation parameter of the effective thickness meets a predetermined stability condition.

[0008] According to an embodiment of this application, a first signal processing unit includes: a time-to-digital converter configured to determine a start time corresponding to a start electrical signal and a termination time corresponding to a termination electrical signal; and a processor configured to determine a time difference based on the start time and the termination time, and to determine the effective thickness of the carbon film to be cleaned after being cleaned by the ion cleaning module based on the time difference.

[0009] According to an embodiment of this application, the cleaning execution device further includes: a volatile substance measurement module disposed in a vacuum cavity and configured to output a dark count rate when cleaning is performed using a laser beam; and a control device communicatively connected to the volatile substance measurement module and configured to control the start and stop of the laser cleaning module based on the dark count rate.

[0010] According to an embodiment of this application, a volatile substance measurement module includes: a third detector configured to output an electrical signal during cleaning using a laser beam; a second signal processing unit configured to process the electrical signal to generate a dark count rate; and / or a control device configured to control the laser cleaning module to suspend operation when the change in the dark count rate matches the expected change.

[0011] According to an embodiment of this application, the cleaning execution device further includes: a rotatable support assembly disposed in a vacuum cavity, comprising: a carbon film support having a mounting surface for mounting at least one carbon film to be cleaned, and an incident-side detector integrated thereon, the incident-side detector serving as a first detector for a thickness measurement module; and a laser support, each of the opposite sides of the laser support integrating a third detector from a laser cleaning module and a volatile substance measurement module, the third detector further configured to serve as a second detector for a thickness measurement module when cleaning is performed using an ion beam; a drive assembly connected to the rotatable support assembly and configured to drive the rotatable support assembly to rotate; and a control device connected to the drive assembly and further configured to control the drive assembly to rotate the rotatable support assembly to sequentially switch the surface of the carbon film to be cleaned on the carbon film support to an ion cleaning station for receiving bombardment cleaning by an ion cleaning module and a laser cleaning station for receiving irradiation cleaning by a laser cleaning module.

[0012] According to an embodiment of this application, an incident-side detector, integrated at the bottom of a carbon film support, includes: two first microchannel plate detectors arranged in a V-shape; and a first anode plate; and / or a third detector, including: two second microchannel plate detectors arranged in a V-shape; and a second anode plate.

[0013] According to an embodiment of this application, a carbon film holder has mounting surfaces for mounting two carbon films to be cleaned, the two mounting surfaces being configured such that both sides of the mounted carbon films to be cleaned are exposed to a vacuum environment; the control device is further configured to control a drive assembly to rotate a rotatable holder assembly to sequentially perform ion cleaning and laser cleaning on the surfaces of the two carbon films to be cleaned according to a predetermined surface switching sequence.

[0014] According to embodiments of this application, an ion cleaning module includes: a gas supply system configured to provide ionized gas; an ion source connected to the gas supply system and configured to generate an ion beam based on the ionized gas; and a beam current control component including: an electrostatic single lens configured to adjust the beam spot size of the ion beam; a collimator configured to collimate the ion beam adjusted by the beam spot size; and / or a laser cleaning module including: a laser configured to generate a laser beam; and a beam shaping component configured to uniformly irradiate the carbon film to be cleaned with the laser beam.

[0015] Another aspect of this application provides a carbon film cleaning method applied to a carbon film cleaning system. The carbon film cleaning system includes a control device, a vacuum chamber, and an execution device disposed in the vacuum chamber. The method may include: using an ion cleaning module included in the execution device to clean contaminants adsorbed on the surface of the carbon film to be cleaned using an ion beam; using a laser cleaning module included in the execution device to clean volatile substances adsorbed on the surface of the carbon film to be cleaned using a laser beam; and using the control device to control the working sequence of the ion cleaning module and the laser cleaning module, such that the ion cleaning module works before the laser cleaning module.

[0016] According to embodiments of this application, an ion beam can physically bombard and remove contaminants such as dust or metal atoms from the contamination layer, reducing the strong absorption of these contaminants by the subsequent laser beam cleaning, which would cause localized energy concentration and damage to the carbon film to be cleaned. Thus, the laser beam can selectively remove volatile contaminants from the surface of the carbon film to be cleaned with a lower risk of damage. The two beams work synergistically in sequence, achieving the removal of different types of contaminants while reducing over-cleaning or structural damage to the carbon film. This improves cleaning efficiency and purity while ensuring the effective thickness of the carbon film to be cleaned remains within a predetermined range, thereby enhancing space particle detection efficiency. Furthermore, setting the cleaning process within a vacuum chamber isolates the carbon film from the external atmosphere, reducing secondary pollution and ensuring timely removal of contaminants generated during cleaning, thus improving the cleaning effect. Attached Figure Description

[0017] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments of this application with reference to the accompanying drawings.

[0018] Figure 1A schematic diagram of a carbon film cleaning system according to an embodiment of this application is shown.

[0019] Figure 2 A schematic diagram of the structure of a cleaning execution device according to an embodiment of this application is shown.

[0020] Figure 3 A schematic diagram of the thickness measurement module according to an embodiment of this application is shown.

[0021] Figure 4 A schematic diagram of the structure of a first signal processing unit according to an embodiment of this application is shown.

[0022] Figure 5 A schematic diagram of another cleaning execution device according to an embodiment of this application is shown.

[0023] Figure 6 A schematic diagram of the structure of a volatile substance measurement module according to an embodiment of this application is shown.

[0024] Figure 7 A schematic diagram of the structure of a rotatable support assembly according to an embodiment of this application is shown.

[0025] Figure 8 A schematic diagram of the incident-side detector according to an embodiment of this application is shown.

[0026] Figure 9 A schematic diagram of another carbon film cleaning system according to an embodiment of this application is shown. Detailed Implementation

[0027] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0029] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0030] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0031] Space is filled with a wide variety of particles. These particles can include charged particles, neutral particles, and cosmic rays. Charged particles can include radiation belts, high-energy solar particles, solar wind plasma, or galactic cosmic rays. Neutral particles can include solar neutrons, atmospheric neutrons, neutral atoms, or cosmic dust. Cosmic rays can include streams of high-energy particles originating from outside Earth (e.g., streams of charged particles or streams of neutral particles).

[0032] High-energy solar particle events can cause disturbances in the space plasma environment, leading to an increase in the flux of high-energy charged particles in near-Earth space. These events can interfere with satellite operations, affect spacecraft electronic systems, and even endanger astronaut safety. They can also influence the coupling processes between the Earth's magnetosphere and ionosphere, potentially triggering geomagnetic storms. Therefore, the detection and research of space particles are of high scientific value and practical significance for understanding space weather mechanisms, ensuring the safety of space activities, and maintaining the stability of the Earth's space environment.

[0033] In related technologies, space particles can be distinguished by the ionization and excitation effects produced by their interaction with matter atoms. Since different space particles produce different interaction curves with matter atoms, the types of space particles can be identified by recording their number or measuring their intensity, thus determining their energy, momentum, or flight direction. Based on this, space particle detectors can be manufactured.

[0034] Space particle detectors can include time-of-flight ion mass spectrometers and neutral particle detectors. They detect space particles by utilizing charge exchange and secondary electron emission effects resulting from the interaction between space particles and carbon films. However, during the fabrication and subsequent transfer of carbon films, pollutants such as water vapor or airborne gases from the environment are adsorbed. The presence of these pollutants causes variations in the carbon film thickness, which in turn affects the secondary electron generation rate, charge conversion efficiency, particle angular scattering, or particle energy loss resulting from the interaction between space particles and the carbon film. This, in turn, affects the performance parameters of the space particle detector, such as its mass resolution, energy resolution, or instrument sensitivity, thus impacting its detection efficiency.

[0035] In view of this, embodiments of this application provide a carbon film cleaning system that performs ion cleaning and laser cleaning on the carbon film to be cleaned according to a working sequence, ensuring that the effective thickness of the carbon film to be cleaned is within a preset thickness range, thereby improving the efficiency of space particle detection. The carbon film to be cleaned can be an ultrathin carbon film.

[0036] Figure 1 A schematic diagram of a carbon film cleaning system according to an embodiment of this application is shown.

[0037] like Figure 1 As shown, the carbon film cleaning system 100 may include a cleaning actuator 110 and a control device 120. The control device 120 may be communicatively connected to the cleaning actuator 110.

[0038] The cleaning execution device 110 may include a vacuum chamber 111, an ion cleaning module 112 disposed in the vacuum chamber 111, and a laser cleaning module 113 disposed in the vacuum chamber 111.

[0039] The vacuum chamber 111 can be configured to provide a vacuum environment. The control device 120 can be configured to control the operating timing of the ion cleaning module 112 and the laser cleaning module 113, such that the ion cleaning module 112 operates before the laser cleaning module 113.

[0040] The ion cleaning module 112 can be configured to use an ion beam to clean contaminants adsorbed on the surface of the carbon film 200 to be cleaned.

[0041] The ion cleaning module 112 can use an ion beam to bombard the surface of the carbon film 200 to be cleaned, physically sputtering away the contaminant layer adsorbed on the surface of the carbon film 200. The contaminant layer may include dust or metal atoms. This process utilizes the physical sputtering effect and energy transfer mechanism of the ion beam to clean the carbon film 200. When ions (e.g., hydrogen ions) in the ion beam bombard the surface (emission surface) of the carbon film 200 to be cleaned, energy is transferred to the contaminant atoms through momentum transfer. If the energy transferred to the contaminant atoms is greater than or equal to the binding energy (or adsorption energy) between the contaminant atoms and the surface of the carbon film 200 to be cleaned, the contaminant atoms are sputtered away from the surface of the carbon film 200 to be cleaned. The ion energy of the ion beam can be less than or equal to a predetermined ion energy threshold. The predetermined ion energy threshold can reduce damage to the carbon film 200 itself while meeting cleaning requirements; for example, the predetermined ion energy threshold can be 10 keV. The ion beam energy can be concentrated on the atomic layer of the surface of the carbon film 200 to be cleaned. Through cascading collisions, the atoms of contaminants gain sufficient kinetic energy to sputter off the surface, for example, metal atoms are sputtered off or dust is peeled off. In this way, the carbon film 200 to be cleaned is cleaned.

[0042] The laser cleaning module 113 can be configured to use a laser beam to clean volatile substances adsorbed on the surface of the carbon film 200 to be cleaned.

[0043] The laser cleaning module 113 can selectively remove at least one of the following: water vapor or volatile substances adsorbed on the carbon film 200, by irradiating the surface of the carbon film 200 with a laser beam. For example, volatile substances may include organic residues or hydrocarbons. This process involves the vaporization and stripping of water vapor and volatile substances adsorbed on the carbon film 200 by the laser beam. For example, water vapor can be desorbed by heating and vaporizing upon absorbing laser energy. Volatile substances can be converted into volatile small molecules and detached from the surface of the carbon film 200 by photothermal decomposition or photochemical bond breaking. By configuring the laser parameters, the heat-affected zone can be confined to the contamination layer, thereby reducing heat conduction to the carbon film substrate, maintaining the cleaning process at a lower temperature, and reducing the risk of damage and structural destruction to the carbon film 200. Laser parameters may include at least one of the following: laser mode, laser wavelength, or laser beam energy. For example, the laser mode may include a pulsed mode or a continuous wave mode. The laser wavelength can be a band that is weakly absorbed by the carbon film 200 itself but strongly absorbed by water vapor and volatile substances. As one implementation method, the laser wavelength can be the blue light wavelength, for example, the laser wavelength can be 457nm. In addition, the energy of the laser beam can be 3W.

[0044] Since the carbon film 200 to be cleaned is highly sensitive to the energy of the laser beam, it is necessary to control the operating sequence of the ion cleaning module 112 and the laser cleaning module 113, so that the ion cleaning module 112 prioritizes cleaning the carbon film 200. This allows the ion beam to pre-remove surface dust or metal atoms from the carbon film 200, reducing the damage to the carbon film 200 caused by localized energy concentration when the laser beam cleans it subsequently. The vacuum environment provided by the vacuum chamber 111 isolates the carbon film 200 from the outside atmosphere during the cleaning process, reducing the risk of re-contamination by moisture or dust in the air. Furthermore, it reduces the attenuation caused by the interaction between the ion beam and air, improving the cleaning effect of both ion and laser cleaning, and ensuring that the removed contaminants are promptly removed, reducing the risk of re-depositing on the surface of the carbon film 200.

[0045] According to embodiments of this application, an ion beam can physically bombard and remove contaminants such as dust or metal atoms from the contamination layer, reducing the strong absorption of these contaminants by the subsequent laser beam cleaning, which would cause localized energy concentration and damage to the carbon film to be cleaned. Thus, the laser beam can selectively remove volatile contaminants from the surface of the carbon film to be cleaned with a lower risk of damage. The two beams work synergistically in sequence, achieving the removal of different types of contaminants while reducing over-cleaning or structural damage to the carbon film. This improves cleaning efficiency and purity while ensuring the effective thickness of the carbon film to be cleaned remains within a predetermined range, thereby enhancing space particle detection efficiency. Furthermore, setting the cleaning process within a vacuum chamber isolates the carbon film from the external atmosphere, reducing secondary pollution and ensuring timely removal of contaminants generated during cleaning, thus improving the cleaning effect.

[0046] Figure 2 A schematic diagram of the structure of a cleaning execution device according to an embodiment of this application is shown.

[0047] like Figure 2 As shown, the cleaning actuator 110 may further include a thickness measurement module 114 disposed in the vacuum chamber 111. The control device 120 may be communicatively connected to the thickness measurement module 114.

[0048] The thickness measurement module 114 can be configured to detect the electrical signal before and after the interaction between the ion beam and the carbon film 200 to be cleaned, and determine the effective thickness of the carbon film 200 to be cleaned after being cleaned by the ion cleaning module 112 based on the electrical signal before and after the interaction between the ion beam and the carbon film 200 to be cleaned.

[0049] The control device 120 can be configured to control the operating state of the ion cleaning module 112 according to the effective thickness.

[0050] The ion beam can interact with the carbon film 200 to be cleaned. During the cleaning process, the ion beam bombards the carbon film 200, generating electrical signals upon its entry into and exit from the film. These signals correspond to the incident energy (energy of the ion beam reaching the carbon film 200) and the exit energy (energy of the ion beam passing through the carbon film 200), respectively. The effective thickness is obtained based on the incident and exit ion beam energies. The control device 120 can determine whether the ion cleaning module 112 has completed the cleaning of the carbon film 200 based on the effective thickness. This determines whether to activate the laser cleaning module 113.

[0051] According to embodiments of this application, the effective thickness of the carbon film to be cleaned after being cleaned by the ion cleaning module is determined based on the electrical signals before and after the interaction between the ion beam and the carbon film to be cleaned (i.e., incident and exit). Therefore, by utilizing the difference in electrical signals generated before and after the ion beam bombards the carbon film to be cleaned, the detection resolution of minute thickness changes in the carbon film to be cleaned is improved, the accuracy of determining the cleaning endpoint of the ion cleaning module is increased, and the difficulty of determining the effective thickness is reduced. By controlling the operating state of the ion cleaning module based on the effective thickness, over- or under-cleaning of the carbon film to be cleaned can be reduced, thereby improving the cleaning efficiency and cleaning effect.

[0052] Figure 3 A schematic diagram of the thickness measurement module according to an embodiment of this application is shown.

[0053] like Figure 3 As shown, the thickness measurement module 114 may include a first detector 114-1 disposed on one side of the carbon film 200 to be cleaned relative to the incident direction of the ion beam, a second detector 114-2 disposed on one side of the carbon film 200 to be cleaned relative to the exit direction of the ion beam, and a first signal processing unit 114-3.

[0054] The first detector 114-1 can be configured to provide an initial electrical signal by detecting secondary electrons generated by the bombardment of the carbon film 200 to be cleaned by an ion beam. As one implementation, the first detector 114-1 may include two first microchannel plate (MCP) detectors and a first anode plate. MCP detectors are vacuum electron multiplier devices that can be used to amplify and detect weak electronic signals (e.g., secondary electrons or photon-excited electrons). Secondary electrons can refer to low-energy electrons that are excited from within a material and escape from the surface after being bombarded by incident particles.

[0055] Due to the inherent characteristics of the carbon film 200 to be cleaned, namely that the electrons are in a half-filled or nearly fully filled state, the band gap between the valence band and the conduction band is relatively narrow, the electron density in the valence band is relatively high, the electrons are easily excited, and the work function of the carbon film 200 to be cleaned is relatively low, the valence band electrons can overcome the surface barrier and escape after gaining a small amount of energy.

[0056] The first detector 114-1 can receive secondary electrons from one side of the carbon film 200 to be cleaned relative to the incident direction of the ion beam, denoted as the first secondary electrons. The first detector 114-1 can amplify the first secondary electrons to form a first electron cloud. The first electron cloud can bombard the first anode plate to generate a first charge signal on the first anode plate. The first charge signal is amplified by the first amplifier to obtain the initial electrical signal.

[0057] The second detector 114-2 can be configured to provide a termination electrical signal by detecting ions emitted after the ion beam passes through the carbon film 200 to be cleaned. As one implementation, the second detector 114-2 may include two second microchannel plate detectors and a second anode plate.

[0058] The second detector 114-2 can receive secondary electrons from one side of the carbon film 200 to be cleaned relative to the emission direction of the ion beam, denoted as the second secondary electrons. The second detector 114-2 can amplify the second secondary electrons to form a second electron cloud. The second electron cloud bombards the second anode plate, causing the second anode plate to generate a second charge signal. The second charge signal is amplified by the second amplifier to obtain a termination electrical signal.

[0059] The first signal processing unit 114-3 can be configured to determine the effective thickness of the carbon film 200 to be cleaned by the ion cleaning module 112 based on the start electrical signal and the end electrical signal.

[0060] For example, the first signal processing unit 114-3 can determine the energy of the ion beam incident on the carbon film 200 to be cleaned and the energy of the ion beam exiting after passing through the carbon film 200 to be cleaned based on the start electrical signal and the end electrical signal. Based on the difference between the energy of the ion beam incident on the carbon film 200 to be cleaned and the energy of the ion beam exiting after passing through the carbon film 200 to be cleaned, the effective thickness of the carbon film 200 to be cleaned cleaned by the ion cleaning module 112 is determined.

[0061] Therefore, the control device 120 can be configured to control the ion cleaning module 112 to suspend operation when the variation parameter of the effective thickness meets a predetermined stability condition. As one implementation method, the variation parameter may include the rate of change. The predetermined stability condition may include, over N measurement cycles, the rate of change of the effective thickness being less than or equal to a predetermined rate of change threshold. N can be an integer greater than or equal to 1.

[0062] For example, if the effective thickness change rate is less than or equal to a predetermined change rate threshold for N consecutive measurement cycles, the control device 120 can determine that the cleaning of contaminants adsorbed on the surface of the carbon film 200 to be cleaned has been completed, and the ion cleaning module 112 needs to be stopped.

[0063] According to embodiments of this application, the effective thickness is determined by the difference between the energy of the ion beam incident on the carbon film to be cleaned and the energy of the ion beam exiting after passing through the carbon film. This improves the accuracy of determining the effective thickness. Based on whether the effective thickness meets predetermined stability conditions, it is determined whether to control the ion cleaning module to pause operation, reducing the probability of abnormal interruptions due to over- or under-cleaning, and improving the operational stability of the ion cleaning module and the accuracy of controlling the cleaning duration.

[0064] exist Figure 3 On this basis, Figure 4 A schematic diagram of the structure of a first signal processing unit according to an embodiment of this application is shown.

[0065] like Figure 3 and Figure 4 As shown, the first signal processing unit 114-3 may include a time-to-digital converter 114-31 and a processor 114-32.

[0066] The first signal processing unit 114-3 can be configured to determine the start time corresponding to the start electrical signal and the end time corresponding to the end electrical signal.

[0067] The processor 114-32 can be configured to determine the time difference based on the start time and the end time, and determine the effective thickness of the carbon film 200 to be cleaned after being cleaned by the ion cleaning module 112 based on the time difference.

[0068] The time-to-digital converter 114-31 is an electronic instrument that converts analog signals into digital signals expressed in time. It achieves digital conversion by measuring the phase difference or time difference between the signal under test and a reference clock signal. Therefore, the time-to-digital converter 114-31 can determine the moment the ion beam enters the carbon film 200 to be cleaned (i.e., the start time) and the moment it exits after passing through the carbon film 200 (i.e., the end time) based on the time difference between the start and end times, thus obtaining the time difference between the start and end times (i.e., the time of flight). Based on the time difference, the incident energy of the ion beam (i.e., the energy of the ion beam entering the carbon film 200 to be cleaned) and the exit energy (i.e., the energy of the ion beam exiting after passing through the carbon film 200 to be cleaned) are determined. Based on the incident and exit ion beam energies, the effective thickness of the carbon film to be cleaned after cleaning by the ion cleaning module 112 is determined.

[0069] For example, the effective thickness can satisfy the following formula (1).

[0070] (1)

[0071] Nd can represent the effective thickness, and the unit can be μg / cm. 2 k can represent the unit conversion factor, k=19.9. E0 can represent the incident energy of the ion beam. E1 can represent the exit energy of the ion beam. a0, a1, and a2 can represent free parameters.

[0072] According to embodiments of this application, the effective thickness of the carbon film to be cleaned is obtained by using the incident and exit energies of the ion beam, which improves the accuracy and real-time performance of the effective thickness detection. Furthermore, this configuration enables non-destructive detection of the effective thickness of the carbon film to be cleaned, effectively reducing damage to the film.

[0073] Figure 5 A schematic diagram of another cleaning execution device according to an embodiment of this application is shown.

[0074] like Figure 5 As shown, the cleaning actuator 110 may further include a volatile substance measurement module 115 disposed in the vacuum chamber 111. The control device 120 may be communicatively connected to the volatile substance measurement module 115.

[0075] The volatile substance measurement module 115 can be configured to output a dark count rate when cleaning is performed using a laser beam.

[0076] The control device 120 can be configured to control the start and stop of the laser cleaning module 113 according to the dark count rate.

[0077] Dark count rate refers to the number of false trigger pulses caused by thermal noise, electrical noise, or stray light in the absence of photon incident. After the ion cleaning module 112 completes cleaning of the carbon film 200 to be cleaned, it can be turned off, and the laser cleaning module 113 can be started. During the cleaning process of the carbon film 200 using the laser cleaning module 113, the volatilization of volatile substances will trigger a dark count rate. As the volatile substances volatilize, the dark count rate will gradually increase; as the volatile substances are removed, the dark count rate will gradually decrease. Therefore, based on the increase and decrease of the dark count rate, it can be determined whether the volatile substances have been completely removed, and thus whether the laser cleaning module 113 should continue to operate.

[0078] According to embodiments of this application, the start and stop of the laser cleaning module are determined based on the rise and fall of the dark count rate, thereby improving the accuracy of determining the cleaning endpoint of the laser cleaning module. Controlling the operating state of the laser cleaning module based on the dark count rate can improve the cleaning effect of the laser cleaning module on the carbon film to be cleaned, reduce the probability of over-cleaning or under-cleaning, and thus improve the cleaning efficiency of the carbon film to be cleaned.

[0079] Figure 6 A schematic diagram of the structure of a volatile substance measurement module according to an embodiment of this application is shown.

[0080] like Figure 6 As shown, the volatile substance measurement module 115 may include a third detector 115-1 and a second signal processing unit 115-2.

[0081] The third detector 115-1 can be configured to output an electrical signal when cleaning is performed using a laser beam.

[0082] The second signal processing unit 115-2 can be configured to process electrical signals and generate a dark count rate.

[0083] The control device 120 can be configured to control the laser cleaning module 113 to stop working when the change in the dark count rate matches the expected change.

[0084] The third detector 115-1 will spontaneously generate electrical pulses when there is no photon signal incident. These electrical pulses are noise signals, and the corresponding count rate can be the dark count rate. The control device 120 can determine that the cleaning of volatile substances on the carbon film 200 to be cleaned has been completed when the dark count rate is within a predetermined range (i.e., matching the expected change) after a predetermined time. Therefore, it is necessary to control the laser cleaning module 113 to stop working.

[0085] According to the embodiments of this application, by determining whether the dark count rate matches the expected change, it is determined whether to control the laser cleaning module to pause operation, thereby reducing the probability of abnormal interruption caused by over- or under-cleaning, and improving the working stability of the laser cleaning module and the control accuracy of the cleaning time.

[0086] Figure 7 A schematic diagram of the structure of a rotatable support assembly according to an embodiment of this application is shown.

[0087] like Figure 7 As shown, the cleaning actuator may also include a rotatable support assembly 111-4 disposed in the vacuum chamber.

[0088] The rotatable support assembly 111-4 may include a carbon film support 111-41, a laser support 111-42, and a drive assembly 111-5 connected to the rotatable support assembly 111-4 and the control device 120.

[0089] The carbon film holder 111-41 may have mounting surfaces for mounting at least one carbon film 200 to be cleaned, and an integrated incident-side detector. Figure 7 (Not shown). The incident-side detector can be used as the first detector 114-1 of the thickness measurement module. The first detector 114-1 provides an initial electrical signal by detecting secondary electrons generated by the ion beam bombardment of the carbon film 200 to be cleaned.

[0090] The laser holder 111-42 integrates a laser cleaning module 113 and a third detector 115-1 from a volatile substance measurement module on opposite sides. When cleaning is performed using a laser beam, the third detector 115-1 can output an electrical signal. Furthermore, the third detector 115-1 can also be configured to function as a second detector in a thickness measurement module when cleaning is performed using an ion beam. Figure 7 (Not shown). A second detector can be used to provide a termination electrical signal by detecting ions emitted after the ion beam passes through the carbon film 200 to be cleaned.

[0091] The drive assembly 111-5 can be configured to drive the rotatable bracket assembly 111-4 to rotate.

[0092] The control device 120 can be configured to control the drive assembly 111-5 to rotate the rotatable support assembly 111-4, so as to sequentially switch the surface of the carbon film 200 to be cleaned on the carbon film support 111-41 to the ion cleaning station for receiving bombardment cleaning by the ion cleaning module. Figure 7 (not shown), and a laser cleaning station for receiving irradiation cleaning from the laser cleaning module 113 .... Figure 7 (Not shown).

[0093] The control device 120 can drive the laser bracket 111-42 to rotate by controlling the drive component 111-5, so that the position of the laser cleaning module 113 (i.e. the laser cleaning station) is aligned with the surface of the carbon film 200 to be cleaned, thereby enabling the laser cleaning module 113 to clean the carbon film 200 to be cleaned.

[0094] The control device 120 can drive the carbon film support 111-41 to rotate by controlling the drive component 111-5, so that the position of the ion cleaning module (i.e., the ion cleaning station) is aligned with the surface of the carbon film 200 to be cleaned, thereby enabling the ion cleaning module to clean the carbon film 200 to be cleaned.

[0095] According to embodiments of this application, by driving the carbon film support and the laser support through the driving component, the ion cleaning module and the laser cleaning module can perform all-round cleaning of the carbon film to be cleaned.

[0096] exist Figure 7 On this basis, Figure 8 A schematic diagram of the incident-side detector according to an embodiment of this application is shown.

[0097] like Figure 8 As shown, the incident-side detector can be integrated into the bottom of the carbon film support 111-41. The incident-side detector may include a first anode plate 114-12 and two first microchannel plate detectors 114-11 arranged in a V-shape.

[0098] The third detector 115-1 may include a second anode plate 115-12 and two second microchannel plate detectors 115-11 arranged in a V-shape.

[0099] Since the detection field of a single first microchannel plate detector 114-11 or second microchannel plate detector 115-11 is limited, it can receive particles or photons along a predetermined direction. By adopting a V-shaped arrangement, the detection surfaces of the two first microchannel plate detectors 114-11 or the two second microchannel plate detectors 115-11 are at a certain angle, which is equivalent to superimposing the two fields of view complementaryly, thereby increasing the effective detection solid angle.

[0100] According to embodiments of this application, by arranging the two second microchannel plate detectors in a V-shape, the effective detection solid angle is increased, thereby improving the accuracy of the termination electrical signal when cleaning with an ion beam or the accuracy of the electrical signal when cleaning with a laser beam. Similarly, by arranging the two first microchannel plate detectors 114-11 in a V-shape, the effective detection solid angle is increased, thereby improving the accuracy of the initiation electrical signal when cleaning with an ion beam.

[0101] The carbon film holder 111-41 may have mounting surfaces for mounting two carbon films 200 to be cleaned. The two mounting surfaces may be configured such that both sides of the mounted carbon film 200 are exposed to a vacuum environment. Thus, the control device 120 may be configured to control the drive assembly 111-5 to rotate the rotatable holder assembly 111-4, sequentially performing ion cleaning and laser cleaning on the surfaces of the two carbon films 200 according to a predetermined surface switching sequence.

[0102] The control device 120 can drive the rotatable bracket assembly 111-4 to rotate by controlling the drive assembly 111-5, so that the carbon film bracket 111-41 can fully perform ion cleaning and laser cleaning on the two mounting surfaces of the carbon film 200 to be cleaned in a predetermined surface switching sequence.

[0103] According to embodiments of this application, by rotating the rotatable support assembly in a predetermined surface switching sequence, ion cleaning and laser cleaning are sequentially performed on the surfaces of the two carbon films to be cleaned. This ensures that the surfaces of the two carbon films to be cleaned are accurately aligned with the ion cleaning module or the laser cleaning module, thereby enabling both mounting surfaces of the carbon films to be cleaned to undergo ion cleaning and laser cleaning, thus improving the cleaning efficiency of the carbon films.

[0104] exist Figure 1 , Figure 4 and Figure 7 On this basis, Figure 9 A schematic diagram of another carbon film cleaning system according to an embodiment of this application is shown.

[0105] like Figure 9 As shown, the ion cleaning module may include a gas supply system 112-1, an ion source 112-2 connected to the gas supply system, and a beam control component. The beam control component may include an electrostatic single lens 112-31 and a collimator 112-32.

[0106] The gas supply system 112-1 can be configured to provide ionized gas. The ion source 112-2 can be configured to generate an ion beam based on the ionized gas. The electrostatic single lens 112-31 can be configured to adjust the beam spot size of the ion beam. The collimator 112-32 can be configured to collimate the ion beam adjusted by the beam spot size. As one implementation, the collimator 112-32 can be positioned between the ion source 112-2 and the carbon film support 111-41, and can employ a slit structure.

[0107] The laser cleaning module may include a laser 113-1 and a beam shaping component 113-2.

[0108] Laser 113-1 can be configured to generate a laser beam. Beam shaping component 113-2 can be configured to make the laser beam uniformly irradiate the carbon film 200 to be cleaned.

[0109] The ion cleaning module 112 will now be described using hydrogen as the ionizing gas. The gas supply system 112-1 supplies ionizing gas (e.g., hydrogen) to the ion source 112-2. The ion source 112-2 is regulated by an electrostatic single lens 112-31. + The beam spot size of the ion beam allows the carbon film 200 to be cleaned to be subjected to H... + Ion beam bombardment is used to achieve cleaning. + After passing through an electrostatic single lens 112-31, the ion beam undergoes collimation processing via collimator 112-32, followed by H... +An ion beam bombards the carbon film 200 to be cleaned, performing ion cleaning on the carbon film 200. A laser beam generated by laser 113-1 passes through a beam shaping component 113-2, such as a laser diverging lens, to uniformly irradiate the carbon film 200 to be cleaned, performing laser cleaning on the carbon film 200.

[0110] In addition, the carbon film cleaning system may also include a vacuum pumping device 130 and a vacuum gauge 140. The vacuum pumping device 130 may be configured to extract gas from the vacuum chamber 111. The vacuum gauge 140 may be configured to monitor the degree of vacuum in the vacuum chamber 111.

[0111] also, Figure 9 For descriptions of other components, please refer to the relevant sections above; they will not be repeated here.

[0112] According to embodiments of this application, the ionized gas provided by the gas supply system is lightweight and has a low sputtering threshold, allowing for gentle removal of surface contaminants while minimizing damage to the carbon film to be cleaned. By adjusting the voltage of the electrostatic single lens, the beam spot size of the ion beam can be flexibly changed to achieve uniform coverage of the carbon film to be cleaned, thereby achieving overall uniform cleaning of the carbon film and reducing local omissions or over-bombardment. The collimated ion beam has more uniform energy and direction, improving the uniformity and accuracy of ion cleaning. The beam shaping component further enhances the uniformity of the laser beam, improving the uniformity and accuracy of laser cleaning.

[0113] The carbon film cleaning system described in this application can effectively remove impurities adsorbed during the fabrication and transfer of the carbon film to be cleaned. This not only reduces the effective thickness of the carbon film but also effectively cleans its surface. The cleaned carbon film, when applied to a space particle detector, can improve the detector's performance parameters and provide a precise physical environment for space particle measurements.

[0114] This application also provides a carbon film cleaning method for use in a carbon film cleaning system. The carbon film cleaning method can be implemented in the following manner.

[0115] The actuator includes an ion cleaning module that uses an ion beam to clean contaminants adsorbed on the surface of the carbon film to be cleaned. The actuator also includes a laser cleaning module that uses a laser beam to clean volatile substances adsorbed on the surface of the carbon film. A control device controls the operating sequence of the ion cleaning module and the laser cleaning module, ensuring that the ion cleaning module operates before the laser cleaning module.

[0116] This application also provides a space particle detector. The space particle detector may include the carbon film cleaning system described in this application.

[0117] Those skilled in the art will understand that the features described in the various embodiments of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. In particular, the features described in the various embodiments of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application. All such combinations and / or combinations fall within the scope of this application.

[0118] The embodiments of this application have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of this application. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of this application, those skilled in the art can make various substitutions and modifications, all of which should fall within the scope of this application.

Claims

1. A carbon film cleaning system, characterized in that, include: Cleaning actuator, including: A vacuum chamber configured to provide a vacuum environment; An ion cleaning module is disposed in the vacuum chamber and configured to use an ion beam to clean dust or metal atoms adsorbed on the surface of the carbon film to be cleaned. A laser cleaning module, disposed within the vacuum chamber, is configured to use a laser beam to clean volatile substances adsorbed on the surface of the carbon film to be cleaned; and A control device, communicatively connected to the cleaning execution device, is configured to control the working sequence of the ion cleaning module and the laser cleaning module, such that the ion cleaning module works before the laser cleaning module. The cleaning actuator further includes: A thickness measurement module, disposed in the vacuum cavity, includes: A first detector is disposed on one side of the carbon film to be cleaned relative to the incident direction of the ion beam, and is configured to provide an initial electrical signal by detecting secondary electrons generated by the ion beam bombarding the carbon film to be cleaned. A second detector, disposed on one side of the carbon film to be cleaned relative to the emission direction of the ion beam, is configured to provide a termination electrical signal by detecting ions after the ion beam has passed through the carbon film to be cleaned; and The first signal processing unit is configured to determine the effective thickness of the carbon film to be cleaned by the ion cleaning module based on the start electrical signal and the termination electrical signal. The control device is communicatively connected to the thickness measurement module and is configured to control the ion cleaning module to pause operation when the variation parameters of the effective thickness meet a predetermined stability condition.

2. The carbon film cleaning system according to claim 1, characterized in that, The first signal processing unit includes: A time-to-digital converter is configured to determine a start time corresponding to the start electrical signal and to determine an end time corresponding to the end electrical signal; and The processor is configured to determine a time difference based on the start time and the end time, and to determine the effective thickness of the carbon film to be cleaned after being cleaned by the ion cleaning module based on the time difference.

3. The carbon film cleaning system according to claim 1 or 2, characterized in that, The cleaning actuator further includes: A volatile substance measurement module is disposed in the vacuum cavity and configured to output a dark count rate when cleaning is performed using the laser beam; The control device is communicatively connected to the volatile substance measurement module and is configured to control the start and stop of the laser cleaning module according to the dark count rate.

4. The carbon film cleaning system according to claim 3, characterized in that, The volatile substance measurement module includes: a third detector configured to output an electrical signal during cleaning using the laser beam; and a second signal processing unit configured to process the electrical signal to generate the dark count rate; and / or The control device is configured to control the laser cleaning module to pause operation when the change in the dark count rate matches the expected change.

5. The carbon film cleaning system according to claim 3, characterized in that, The cleaning actuator further includes: A rotatable support assembly, disposed in the vacuum chamber, includes: A carbon film holder having mounting surfaces for mounting at least one of the carbon films to be cleaned, and an integrated incident-side detector serving as a first detector for a thickness measurement module; and A laser bracket, wherein the laser cleaning module and the third detector of the volatile substance measurement module are integrated on opposite sides of the laser bracket, and the third detector is further configured to serve as the second detector of the thickness measurement module when cleaning is performed using the ion beam. A drive component, connected to the rotatable support assembly, is configured to drive the rotatable support assembly to rotate; The control device, connected to the drive assembly, is further configured to control the drive assembly to rotate the rotatable support assembly, thereby sequentially switching the surface of the carbon film to be cleaned on the carbon film support to an ion cleaning station for receiving bombardment cleaning by the ion cleaning module, and a laser cleaning station for receiving irradiation cleaning by the laser cleaning module.

6. The carbon film cleaning system according to claim 5, characterized in that, The incident-side detector, integrated at the bottom of the carbon film support, includes: two first microchannel plate detectors arranged in a V-shape; a first anode plate; and / or The third detector includes: two second microchannel plate detectors arranged in a V-shape; and a second anode plate.

7. The carbon film cleaning system according to claim 6, characterized in that, The carbon film holder has mounting surfaces for mounting two carbon films to be cleaned, and the two mounting surfaces are configured such that both sides of the mounted carbon films to be cleaned are exposed to the vacuum environment. The control device is further configured to control the drive assembly to rotate the rotatable support assembly, so as to sequentially perform ion cleaning and laser cleaning on the respective surfaces of the two carbon films to be cleaned according to a predetermined surface switching sequence.

8. The carbon film cleaning system according to claim 1 or 2, characterized in that, The ion cleaning module includes: a gas supply system configured to provide ionized gas; an ion source connected to the gas supply system and configured to generate an ion beam based on the ionized gas; and a beam current control component including: an electrostatic single lens configured to adjust the beam spot size of the ion beam; a collimator configured to collimate the ion beam adjusted by the beam spot size; and / or The laser cleaning module includes: a laser configured to generate a laser beam; and a beam shaping component configured to uniformly irradiate the carbon film to be cleaned by the laser beam.

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