Ion pump testing system, method, and storage medium based on electron microscopy imaging

Abstract

The application discloses an ion pump testing system and method based on electron microscope imaging and a storage medium, wherein the system comprises a sample chamber, an electron gun, a mechanical pump group comprising a mechanical pump and a molecular pump, a molecular sieve air pump, a plurality of ion pump groups each comprising at least one standard ion pump and at least one ion pump to be tested, a vacuum degree monitoring device and a beam current monitoring device. Thus, the connection mode of the molecular sieve air pump and the plurality of ion pump groups is changed, the sample chamber and the electron gun vacuum chamber are vacuumized to an ultrahigh vacuum environment by the molecular sieve air pump, the calibration of the vacuum degree monitoring device is realized, the consistency of various parameters in the testing process is ensured, the monitoring result accuracy of the beam current monitoring device is improved, the vacuum stability of the ion pump is represented based on the beam current parameter of the electron gun emitted beam current, the testing result is more objective and accurate, and the vacuum stability comparison test of the plurality of ion pump groups is realized.

Description

Technical Field

[0001] This invention relates to the field of ion pump testing technology, and particularly to an ion pump testing system based on electron microscopy imaging, an ion pump testing method based on electron microscopy imaging, and a computer-readable storage medium. Background Technology

[0002] Currently, the vacuum stability of various ion pumps is typically tested based on the Chinese machinery industry standard JB / T 2765-92, "Performance Test Method for Sputter Ion Pumps." However, this testing method has the following shortcomings: 1. Limited measurement accuracy: This standard method relies on traditional vacuum gauges (such as thermocouple gauges and ionization gauges) for measurement, and these devices have limited measurement accuracy and stability in the extremely high vacuum range; 2. Insufficient dynamic response: This standard method cannot fully reflect the dynamic response characteristics of sputter ion pumps under different operating conditions, especially under rapidly changing gas loads; 3. Difficulty in assessing long-term stability: This standard method is difficult to comprehensively assess the performance changes and stability of sputter ion pumps after long-term operation. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to propose an ion pump testing system based on electron microscopy imaging, which can characterize the vacuum stability of the ion pump based on the beam parameters of the electron gun-emitted beam, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0004] The second objective of this invention is to propose an ion pump testing method based on electron microscopy imaging.

[0005] The third objective of this invention is to propose another ion pump testing method based on electron microscopy imaging.

[0006] The fourth objective of this invention is to propose yet another ion pump testing method based on electron microscopy imaging.

[0007] The fifth objective of this invention is to provide a computer-readable storage medium.

[0008] To achieve the above objectives, the first aspect of the present invention provides an ion pump testing system based on electron microscopy imaging, comprising: a sample chamber adapted to hold an electron microscopy imaging sample; an electron gun adapted to act on the electron microscopy imaging sample with a charged particle beam; a mechanical pump group, comprising a mechanical pump and a molecular pump, adapted to evacuate the sample chamber and the electron gun vacuum chamber to a pre-vacuum environment; a molecular sieve suction pump adapted to evacuate the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, wherein the vacuum degree of the ultra-high vacuum environment is greater than that of the pre-vacuum environment; multiple ion pump groups, each ion pump group comprising at least one standard ion pump and at least one ion pump to be tested, adapted to perform a comparative test of the vacuum stability of the ion pumps; a vacuum degree monitoring device adapted to monitor and display the vacuum degree of the sample chamber and the electron gun vacuum chamber; and a beam current monitoring device adapted to monitor the emitted beam current of the electron gun to obtain beam current parameters, wherein the beam current parameters are used to characterize the vacuum stability of each ion pump group, thereby achieving a vacuum stability test of at least one ion pump.

[0009] The electron microscopy-based ion pump testing system according to embodiments of the present invention can change the connection method of the molecular sieve gas-feeding pump and multiple ion pump groups. The molecular sieve gas-feeding pump evacuates the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment to calibrate the vacuum degree detection device and ensure the consistency of various parameters during the test, thereby improving the accuracy of the beam monitoring device's monitoring results. Thus, the beam parameters based on the electron gun emitted beam characterize the vacuum stability of the ion pump, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0010] In addition, the ion pump testing system based on electron microscopy imaging according to the above embodiments of the present invention may also have the following additional technical features:

[0011] According to an embodiment of the present invention, the beam monitoring device includes: a charged particle beam emission source connected to a high-voltage cathode, adapted to generate charged particles; an extraction electrode including a first anode and a second anode, the first anode being connected to the high-voltage anode and adapted to extract the charged particles to form the emission beam, the upper end of the second anode being disposed corresponding to the lower end of the first anode, and the second anode being adapted to focus the emission beam; a first galvanometer connected to the first anode and adapted to monitor the extraction current of the first anode; a power control module adapted to adjust the voltage of the first anode and acquire a monitoring signal corresponding to the extraction current of the first galvanometer; and a signal analysis module adapted to generate the beam parameters based on the monitoring signal corresponding to the extraction current of the first galvanometer.

[0012] According to one embodiment of the present invention, the lower end of the first anode has a flared opening, and the upper end of the second anode has a flared opening.

[0013] According to one embodiment of the present invention, the beam monitoring device further includes: a second galvanometer connected to the charged particle beam emission source and adapted to monitor the emission current of the charged particle beam emission source; a power control module adapted to adjust the voltage of the second anode and acquire the monitoring signal corresponding to the emission current of the second galvanometer; and a signal analysis module adapted to generate the beam parameters based on the monitoring signal corresponding to the lead-out current of the first galvanometer and the monitoring signal corresponding to the emission current of the second galvanometer.

[0014] According to an embodiment of the present invention, the signal analysis module is further adapted to perform frequency domain analysis on the monitoring signal corresponding to the lead-out current of the first galvanometer and the monitoring signal corresponding to the emission current of the second galvanometer to find a first frequency band with similar frequency domain signals; to optimize the stability of the first frequency band portion of the monitoring signal corresponding to the lead-out current of the first galvanometer by adjusting the voltages of the first anode and the second anode; and to collect the monitoring signals of the first galvanometer and the second galvanometer so that the monitoring signal corresponding to the lead-out current of the first galvanometer and the monitoring signal corresponding to the lead-out current of the second galvanometer are superimposed in reverse to generate the beam parameters.

[0015] According to one embodiment of the present invention, the at least one standard ion pump and the at least one test ion pump are connected to the sample chamber or the electron gun vacuum chamber via a Y-shaped tee pipe.

[0016] According to one embodiment of the present invention, the electron microscope is a transmission electron microscope or a scanning electron microscope.

[0017] To achieve the above objectives, a second aspect of the present invention provides an ion pump testing method based on electron microscopy imaging, applied to the ion pump testing system based on electron microscopy imaging as described in the above embodiments of the present invention. The method includes: controlling the mechanical pump group to operate at a preset speed to evacuate the sample chamber and the electron gun vacuum chamber to a pre-vacuum environment; connecting the molecular sieve getter pump to the electron gun vacuum chamber to evacuate the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, and recording the current reading of the vacuum monitoring device; connecting at least two standard ion pumps from the plurality of ion pump groups to the electron gun vacuum chamber and the sample chamber, and disconnecting the molecular sieve getter pump to achieve vacuum stability testing of the at least two standard ion pumps; monitoring the emission beam of the electron gun to obtain the beam parameters corresponding to the standard ion pumps, wherein the beam parameters corresponding to the standard ion pumps are used to characterize the at least two standard ion pumps. The vacuum stability of the pumps is tested by: disconnecting at least two standard ion pumps from the plurality of ion pump groups to restore the sample chamber and the electron gun vacuum chamber to the pre-vacuum environment; reconnecting the molecular sieve getter pump to the electron gun vacuum chamber to evacuate the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, and correcting the current reading of the vacuum monitoring device; connecting at least two ion pumps to be tested from the plurality of ion pump groups to the electron gun vacuum chamber and the sample chamber, and disconnecting the molecular sieve getter pump to achieve vacuum stability testing of the at least two ion pumps to be tested; monitoring the emission beam of the electron gun to obtain the beam parameters corresponding to the ion pumps to be tested, which are used to characterize the vacuum stability of the at least two ion pumps to be tested; and performing vacuum stability testing of at least one ion pump based on the beam parameters corresponding to the standard ion pumps and the beam parameters corresponding to the ion pumps to be tested.

[0018] The electron microscopy-based ion pump testing method according to embodiments of the present invention can characterize the vacuum stability of the ion pump based on the beam parameters of the electron gun emitted beam, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0019] To achieve the above objectives, a third aspect of the present invention provides an ion pump testing method based on electron microscopy imaging, applied to the ion pump testing system based on electron microscopy imaging as described in the above embodiments of the present invention. The method includes: placing a standard sample into the sample chamber, and connecting at least two standard ion pumps from the plurality of ion pump groups to the electron gun vacuum chamber and the sample chamber, thereby evacuating the sample chamber and the electron gun vacuum chamber to a first vacuum environment; selecting a first image target site under electron microscopy imaging, and controlling the emission beam to remain constant; acquiring the image drift value of the first image target site within a preset time period, and forming an image of the corresponding standard ion pump. Image drift curve; at least two ion pumps to be tested from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, and the sample chamber and the electron gun vacuum chamber are evacuated to the first vacuum environment; a second image target site under electron microscopy imaging is selected, and the emission beam is kept constant; the image drift value of the second image target site within a preset time period is obtained, and the corresponding image drift curve of the ion pump to be tested is formed; the vacuum stability of each ion pump group is characterized according to the image drift curve of the corresponding standard ion pump and the image drift curve of the corresponding ion pump to be tested, so as to realize the comparative test of the vacuum stability of the plurality of ion pump groups.

[0020] The electron microscopy-based ion pump testing method according to embodiments of the present invention can characterize the vacuum stability of the ion pump based on the image drift curve, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0021] To achieve the above objectives, a fourth aspect of the present invention proposes an ion pump testing method based on electron microscopy imaging, applied to the ion pump testing system based on electron microscopy imaging as described in the above embodiments of the present invention. The method includes: placing a standard sample into the sample chamber, and connecting at least two standard ion pumps from the plurality of ion pump groups to the electron gun vacuum chamber and the sample chamber, thereby evacuating the sample chamber and the electron gun vacuum chamber to a second vacuum environment; acquiring first image spur parameters of the corresponding standard ion pump under electron microscopy imaging; connecting at least two ion pumps to be tested from the plurality of ion pump groups to the electron gun vacuum chamber and the sample chamber, thereby evacuating the sample chamber and the electron gun vacuum chamber to the second vacuum environment; acquiring second image spur parameters of the corresponding ion pumps to be tested under electron microscopy imaging; characterizing the magnetic leakage of each ion pump group based on the first image spur parameters of the corresponding standard ion pumps and the second image spur parameters of the corresponding ion pumps to be tested, thereby achieving a comparative test of the magnetic leakage of the plurality of ion pump groups.

[0022] The ion pump testing method based on electron microscopy imaging according to embodiments of the present invention can characterize the magnetic leakage of the ion pump based on image spur parameters, and the test results are more objective and accurate, enabling the testing of the magnetic leakage of multiple ion pump groups.

[0023] To achieve the above objectives, a computer storage medium is provided in the fifth aspect embodiment of the present invention, which stores an ion pump testing program based on electron microscopy imaging. When the ion pump testing program based on electron microscopy imaging is executed by a processor, it implements the ion pump testing method based on electron microscopy imaging according to any one of the foregoing second, third and fourth aspect embodiments.

[0024] According to embodiments of the present invention, a computer-readable storage medium, by executing an ion pump test program based on electron microscopy imaging, can characterize the vacuum stability of the ion pump based on the beam parameters of the electron gun emitted beam, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups; or, it can characterize the vacuum stability of the ion pump based on image drift curves, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups; or, it can characterize the magnetic leakage of the ion pump based on image spur parameters, and the test results are more objective and accurate, enabling testing of the magnetic leakage of multiple ion pump groups.

[0025] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0026] Figure 1 This is a block diagram of an ion pump testing system based on electron microscopy imaging according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of an ion pump testing system based on electron microscopy imaging according to a specific embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of a beam monitoring device according to a specific embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the structure of an electron gun according to a specific embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the structure of an electron gun according to another specific embodiment of the present invention;

[0031] Figure 6 This is a schematic flowchart of an ion pump testing system based on electron microscopy imaging according to an embodiment of the present invention;

[0032] Figure 7This is a schematic diagram comparing vacuum gauge readings with beam current variation curves according to an embodiment of the present invention;

[0033] Figure 8 This is a schematic flowchart of an ion pump testing system based on electron microscopy imaging according to another embodiment of the present invention;

[0034] Figure 9 This is a schematic diagram of electron microscopy imaging of target site selection according to an embodiment of the present invention;

[0035] Figure 10 This is a schematic diagram comparing vacuum gauge readings with image drift curves according to an embodiment of the present invention;

[0036] Figure 11 This is a schematic flowchart of an ion pump testing system based on electron microscopy imaging according to another embodiment of the present invention;

[0037] Figure 12 This is a schematic diagram of electron microscopy imaging for measuring image spur parameters according to an embodiment of the present invention;

[0038] Figure 13 This is a schematic diagram of electron microscopy imaging of spur parameters of a standard electronic pump image according to an embodiment of the present invention;

[0039] Figure 14 This is a schematic diagram of electron microscopy imaging of the spur parameters of an electronic pump under test according to an embodiment of the present invention. Detailed Implementation

[0040] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0041] The following description, with reference to the accompanying drawings, describes an ion pump testing system based on electron microscopy imaging, an ion pump testing method based on electron microscopy imaging, and a computer-readable storage medium according to embodiments of the present invention.

[0042] Figure 1 This is a block diagram of an ion pump testing system based on electron microscopy imaging according to an embodiment of the present invention.

[0043] Specifically, in some embodiments of the present invention, such as Figure 1 As shown, the ion pump testing system 1000 based on electron microscopy imaging includes: a sample chamber 10, an electron gun 20, a mechanical pump group 30, a molecular sieve gas pump 40, multiple ion pump groups 50, a vacuum monitoring device 60, and a beam monitoring device 70.

[0044] The sample chamber 10 is suitable for placing an electron microscope imaging sample; the electron gun 20 is suitable for acting on the electron microscope imaging sample with a charged particle beam; the mechanical pump group 30 includes a mechanical pump and a molecular pump, suitable for evacuating the sample chamber 10 and the electron gun 20 vacuum chamber to a pre-vacuum environment; the molecular sieve suction pump 40 is suitable for evacuating the sample chamber 10 and the electron gun 20 vacuum chamber to an ultra-high vacuum environment, wherein the vacuum degree of the ultra-high vacuum environment is greater than that of the pre-vacuum environment; each of the multiple ion pump groups 50 includes at least one standard ion pump and at least one ion pump to be tested, suitable for conducting comparative tests on the vacuum stability of the ion pumps; the vacuum degree monitoring device 60 is suitable for monitoring and displaying the vacuum degree of the sample chamber 10 and the electron gun 20 vacuum chamber; the beam current monitoring device 70 is suitable for monitoring the emitted beam current of the electron gun 20 to obtain beam current parameters, which are used to characterize the vacuum stability of each ion pump group, so as to realize the vacuum stability test of at least one ion pump.

[0045] For example, in some embodiments of the present invention, two ion pump groups are used as an example, such as... Figure 2 As shown, at least one standard ion pump (i.e., ion pump A) and at least one test ion pump (i.e., ion pump B) in one ion pump group are connected to the sample chamber 10. At least one standard ion pump (i.e., ion pump C) and at least one test ion pump (i.e., ion pump D) in another ion pump group are connected to the vacuum chamber of the electron gun 20. The required pumping speed for the electron gun is 25 L / s, and the required pumping speed for the sample chamber is 200 L / s. Therefore, the vacuum environment of the entire system (i.e., the vacuum chamber of sample chamber 10 and the vacuum chamber of electron gun 20) is first evacuated to a pre-vacuum environment (e.g., maintaining the vacuum level at 10) by the mechanical pump group (i.e., mechanical pumps and molecular pumps). -4 The vacuum environment of the entire machine is then evacuated to an ultra-high vacuum environment by a molecular sieve suction pump 40. The vacuum level of the ultra-high vacuum environment is greater than that of the preparatory vacuum environment. This is to unify the initial environment of the mechanical vacuum by unifying the initial environmental variables. Finally, based on the ion pump test requirements, the corresponding standard ion pump and / or the ion pump to be tested are connected to the vacuum environment of the entire machine for evacuation so that the electron gun beam generates different beam parameters. Then, the test results (vacuum level and beam parameters) of the standard ion pump and the ion pump to be tested are compared by the vacuum monitoring device 60 and the beam monitoring device 70 to achieve the vacuum stability test of at least one ion pump.

[0046] Furthermore, in this embodiment of the present invention, such as Figure 2 As shown, the vacuum monitoring device 60 includes a vacuum gauge a, which is used to monitor and display the vacuum level of the sample chamber 10 and the vacuum chamber of the electron gun 20.

[0047] Alternatively, in other embodiments of the invention, such as Figure 2As shown, the vacuum monitoring device 60 also includes vacuum gauge b and vacuum gauge c. Vacuum gauge c can be selected from various types of vacuum gauges such as hot cathode ionization gauges, cold cathode ionization gauges, Pirani resistance gauges, and thermocouple gauges. The lower limit of measurement for vacuum gauge a should be less than or equal to 10. -8 The lower limit of measurement for vacuum gauge b should be less than or equal to 0.1 Pa, and the lower limit of measurement for vacuum gauge c should be less than or equal to 10 Pa. -4 Pa levels are available to meet different vacuum monitoring needs.

[0048] It should be noted that molecular sieve getter pumps have high pumping speed and low ultimate pressure: Molecular sieve getter pumps can provide very high pumping speeds within a specific pressure range, especially in the ultra-high vacuum region. This allows them to rapidly reduce system pressure and reach extremely low ultimate pressures. In addition, molecular sieve getter pumps have chemical adsorption capabilities and long-term stability of ultimate vacuum: Molecular sieve getter pumps not only remove gas molecules through physical adsorption, but also fix certain active gases (such as hydrogen, oxygen, water vapor, etc.) on their surface through chemical reactions. This chemical adsorption capability can more thoroughly remove residual gases, improve the stability of vacuum, and maintain extremely low vacuum for a long time because the adsorbed gas molecules are not easily released again.

[0049] Therefore, in the above embodiments of the present invention, a molecular sieve suction pump is used to calibrate the ultra-high vacuum gauge, thereby improving the comparability of the test results. In subsequent steps, the vacuum gauge can also be calibrated based on the above calibration method to ensure the consistency of various parameters during the experiment, so that the test results of the standard ion pump and the tested ion pump are comparable, and the test results are more objective.

[0050] It should be understood that beam parameters are not only affected by vacuum level, but also by various other factors such as power supply stability, electrode characteristics, system configuration, and beam state. Therefore, in order to reduce the interference of other factors when measuring beam current and to make the measured beam current change directly correlated with vacuum level and have an accurate characterization effect, in some embodiments of the present invention, the beam current monitoring device 70 and its beam current monitoring method are also improved, as follows:

[0051] Furthermore, in some embodiments of the present invention, such as Figure 3 As shown, the beam monitoring device 70 includes: a charged particle beam emission source, an extraction electrode, a first ammeter, a power control module, and a signal analysis module.

[0052] The system includes a charged particle beam emission source connected to a high-voltage cathode to generate charged particles; an extraction electrode comprising a first anode and a second anode connected to a high-voltage anode to extract charged particles and form an emission beam, the upper end of the second anode corresponding to the lower end of the first anode, and the second anode being suitable for focusing the emission beam; a first galvanometer connected to the first anode to monitor the extraction current of the first anode; a power control module to adjust the voltage of the first anode and acquire the monitoring signal corresponding to the extraction current of the first galvanometer; and a signal analysis module to generate beam parameters based on the monitoring signal corresponding to the extraction current of the first galvanometer.

[0053] It is understood that, in this embodiment of the present invention, as Figure 3 As shown, a charged particle beam emission source is connected to a high-voltage cathode to generate charged particles. The first anode in the extraction electrode is connected to the high-voltage anode to extract the charged particles and form an emission beam. The upper end of the second anode is positioned corresponding to the lower end of the first anode to focus the emission beam. At this time, under the combined action of the first and second anodes, the distribution ratio of the emission beam passing through the first anode and impacting the first anode is stabilized, thereby reducing the influence of the beam state on the beam stability.

[0054] Furthermore, in this embodiment of the present invention, such as Figure 3 As shown, the lead-out current of the first anode is monitored by the first ammeter. Then, the voltage of the first anode is adjusted by the power control module and the monitoring signal corresponding to the lead-out current of the first ammeter is collected. The beam parameters are generated by the signal analysis module based on the lead-out current of the first anode. These beam parameters can characterize the beam stability of the emitted beam, thereby reducing the influence of system configuration on beam stability.

[0055] Optionally, in the above embodiments of the present invention, the charged particle beam emission source can be a field emission tip.

[0056] Furthermore, in some embodiments of the present invention, the lower end of the first anode has a flared opening, and the upper end of the second anode has a flared opening.

[0057] It is understood that, in this embodiment of the present invention, as Figure 3 As shown, the lower end of the first anode is preferably funnel-shaped, and the upper end of the second anode is preferably funnel-shaped, to reduce beam fluctuations caused by the emitted beam impacting the sidewalls of the first and second anode channels, thereby reducing the influence of electrode characteristics on beam stability. This improves the accuracy of beam monitoring.

[0058] Furthermore, in some embodiments of the present invention, such as Figure 3As shown, the beam monitoring device 70 further includes: a second ammeter connected to the charged particle beam emission source and adapted to monitor the emission current of the charged particle beam emission source; a power control module adapted to adjust the voltage of the second anode and acquire the monitoring signal corresponding to the emission current of the second ammeter; and a signal analysis module adapted to generate beam parameters based on the monitoring signal corresponding to the lead current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter.

[0059] It is understood that, in this embodiment of the present invention, the lead-out current of the first anode and the emission current of the charged particle beam emission source can be monitored by the first ammeter and the second ammeter, respectively. The power control module collects the monitoring signal corresponding to the lead-out current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter, respectively. Then, the signal analysis module generates beam parameters based on the monitoring signal corresponding to the lead-out current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter.

[0060] Furthermore, in some embodiments of the present invention, the signal analysis module is also adapted to perform frequency domain analysis on the monitoring signal corresponding to the lead-out current of the first galvanometer and the monitoring signal corresponding to the emission current of the second galvanometer to find a first frequency band with similar frequency domain signals; by adjusting the voltage of the first anode and the second anode, the stability of the first frequency band portion of the monitoring signal corresponding to the lead-out current of the first galvanometer is optimized; and the monitoring signals of the first galvanometer and the second galvanometer are acquired so that the monitoring signal corresponding to the lead-out current of the first galvanometer and the monitoring signal corresponding to the lead-out current of the second galvanometer are superimposed in reverse to generate beam parameters.

[0061] Specifically, in this embodiment of the invention, the monitoring signal corresponding to the lead current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter are analyzed in the frequency domain by a signal analysis module to identify a first frequency band with similar frequency domain signals and a second frequency band with significant frequency domain differences. Then, by adjusting the voltage of the first anode and the second anode, the stability of the first frequency band portion of the monitoring signal corresponding to the lead current of the first ammeter is optimized. Then, by acquiring the monitoring signals of the first ammeter and the second ammeter, the monitoring signal corresponding to the lead current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter are superimposed in reverse (i.e., the monitoring signal corresponding to the lead current of the first ammeter is subtracted from the monitoring signal corresponding to the lead current of the second ammeter) to generate beam current parameters, thereby reducing the influence of power supply stability on beam current stability.

[0062] It should be understood that, in the above embodiments of the present invention, similar frequency domain signals refer to the fact that the variation patterns of the two signals in the frequency domain are relatively synchronized.

[0063] Furthermore, in some embodiments of the present invention, at least one standard ion pump and at least one test ion pump are connected to the sample chamber or electron gun vacuum chamber via a Y-shaped tee pipe.

[0064] It is understood that, in this embodiment of the present invention, as Figure 2 As shown, standard ion pump a and test ion pump b can be connected to the sample chamber via a Y-shaped tee pipe, and standard ion pump b and test ion pump d can be connected to the electron gun vacuum chamber via a Y-shaped tee pipe. Therefore, by connecting the ion pumps to be compared simultaneously via the Y-shaped tee pipe, different ion pump testing needs can be met, and changes in environmental variables caused by the disassembly and installation of the ion pumps can be effectively avoided. This ensures that all tests use the same testing system, guaranteeing more objective test results.

[0065] Furthermore, in some embodiments of the present invention, the electron microscope is a transmission electron microscope or a scanning electron microscope.

[0066] It is understood that, in this embodiment of the present invention, the electron microscope can be as follows: Figure 4 The transmission electron microscope shown specifically includes an electron source, extraction electrodes, a condenser lens, an objective lens, an intermediate lens, a projection lens, and a fluorescent screen. The electron microscope can also be as follows: Figure 5 The scanning electron microscope shown includes an electron source, an extraction electrode, an objective lens, and a deflection electrode. The transmission electron microscope or scanning electron microscope uses a charged particle beam to act on the sample and collects various particles to form an image or diffraction pattern. At the same time, in order to ensure that the high-energy charged particle beam can reach the sample and form a clear image, the transmission electron microscope or scanning electron microscope needs to maintain an extremely high vacuum environment to avoid air molecules interfering with the path of the charged particle beam.

[0067] In summary, the electron microscopy-based ion pump testing system according to embodiments of the present invention can change the connection method of the molecular sieve gas-feeding pump and multiple ion pump groups. By using the molecular sieve gas-feeding pump to evacuate the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, the vacuum degree detection device can be calibrated, and the consistency of various parameters during the test can be ensured, thereby improving the accuracy of the beam monitoring device's monitoring results. Thus, the beam parameters based on the electron gun emitted beam characterize the vacuum stability of the ion pump, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0068] Specifically, this embodiment of the invention also proposes an ion pump testing method based on electron microscopy imaging applied to the aforementioned ion pump testing system 1000 based on electron microscopy imaging, such as... Figure 6 As shown, the method includes:

[0069] S101 controls the mechanical pump group to operate at a preset speed, so that the sample chamber and electron gun vacuum chamber are evacuated to a pre-vacuum environment.

[0070] It is understood that, in this embodiment of the invention, the mechanical pump assembly (i.e., the mechanical pump and the molecular pump) operates according to a preset rotational speed until the current reading Pv1 of the vacuum monitoring device (vacuum gauge a) reaches 10. -4 The Pa level is used to evacuate the sample chamber and electron gun vacuum chamber to a pre-vacuum environment.

[0071] S102, connect the molecular sieve suction pump to the electron gun vacuum chamber, evacuate the sample chamber and electron gun vacuum chamber to an ultra-high vacuum environment, and record the current reading of the vacuum monitoring device.

[0072] It is understood that in this embodiment of the present invention, the molecular sieve suction pump is connected until the reading of the vacuum monitoring device (vacuum gauge a) stops decreasing, so that the sample chamber and the electron gun vacuum chamber are evacuated to an ultra-high vacuum environment, and the current reading Pv2 of the vacuum monitoring device (i.e., vacuum gauge a) is recorded.

[0073] S103 connects at least two standard ion pumps from multiple ion pump sets to the electron gun vacuum chamber and the sample chamber, and disconnects the molecular sieve gas pump to achieve vacuum stability testing of at least two standard ion pumps.

[0074] It is understood that in this embodiment of the present invention, both the electron gun vacuum chamber and the sample chamber are connected to a standard ion pump, and then the connection of the molecular sieve gas pump is disconnected until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes at Pv3 (the change is less than a preset value within a preset time).

[0075] Optionally, in this embodiment of the invention, the reading Pv3 of the vacuum monitoring device (vacuum gauge a) can also be used to characterize the relative ultimate vacuum of the standard ion pump connected to the electron gun vacuum chamber and the sample chamber.

[0076] S104 monitors the emitted beam of the electron gun to obtain the beam parameters corresponding to the standard ion pump. The beam parameters corresponding to the standard ion pump are used to characterize the vacuum stability of at least two standard ion pumps.

[0077] It is understood that, in this embodiment of the present invention, by monitoring the emitted beam of the electron gun, the beam parameters corresponding to the standard ion pump are obtained (e.g., the beam variation curve within a set time period, or the beam sampled at a fixed frequency, and the variance of the beam stability is statistically analyzed), thereby characterizing the vacuum stability of at least two standard ion pumps through the beam parameters corresponding to the standard ion pump.

[0078] S105, disconnect at least two standard ion pumps from multiple ion pump groups to restore the sample chamber and electron gun vacuum chamber to the preparatory vacuum environment.

[0079] It is understood that, in this embodiment of the invention, at least two standard ion pumps in a plurality of ion pump groups are disconnected until the current reading Pv1 of the vacuum monitoring device (vacuum gauge a) reaches 10. -4 The Pa level allows the sample chamber and electron gun vacuum chamber to be restored to a pre-vacuum environment.

[0080] S106, connect the molecular sieve suction pump to the electron gun vacuum chamber again, so that the sample chamber and the electron gun vacuum chamber are evacuated to an ultra-high vacuum environment, and correct the current reading of the vacuum monitoring device.

[0081] It is understood that in this embodiment of the present invention, the molecular sieve suction pump is reconnected until the reading of the vacuum monitoring device (vacuum gauge a) no longer decreases, so that the sample chamber and the electron gun vacuum chamber are evacuated to an ultra-high vacuum environment, and the current reading of the vacuum monitoring device is corrected to Pv2, thereby unifying the initial environmental variables and calibrating the initial reading of the vacuum monitoring device.

[0082] S107 connects at least two ion pumps to be tested from multiple ion pump groups to the electron gun vacuum chamber and the sample chamber, and disconnects the molecular sieve gas pump to achieve vacuum stability testing of at least two ion pumps to be tested.

[0083] It is understood that in this embodiment of the present invention, both the electron gun vacuum chamber and the sample chamber are connected to the ion pump to be tested, and then the connection of the molecular sieve gas pump is disconnected until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes at Pv4 (the change is less than the preset value within a preset time).

[0084] Optionally, in this embodiment of the invention, the reading Pv4 of the vacuum monitoring device (vacuum gauge a) can also be used to characterize the relative ultimate vacuum of the ion pump under test connected to the electron gun vacuum chamber and the sample chamber.

[0085] S108 monitors the emitted beam of the electron gun to obtain the beam parameters corresponding to the ion pump under test. The beam parameters corresponding to the ion pump under test are used to characterize the vacuum stability of at least two ion pumps under test.

[0086] It is understood that, in this embodiment of the present invention, by monitoring the emitted beam of the electron gun, the beam parameters corresponding to the standard ion pump are obtained (e.g., the beam change curve within a set time period, or the beam sampled at a fixed frequency, and the variance of the beam stability is statistically analyzed), thereby characterizing the vacuum stability of at least two ion pumps under test through the beam parameters corresponding to the ion pump under test.

[0087] S109, based on the beam parameters corresponding to the standard ion pump and the beam parameters corresponding to the ion pump under test, enables the vacuum stability test of at least one ion pump under test.

[0088] It is understood that, in this embodiment of the present invention, by comparing the beam change curves or the variance of beam stability obtained in step S104 and step S108, the vacuum stability of different ion pumps can be compared, thereby achieving the vacuum stability test of at least one ion pump to be tested.

[0089] The following is combined Figure 7 The specific embodiments of the present invention will be described to illustrate the testing results of the ion pump testing method based on electron microscopy imaging.

[0090] Specifically, the readings of the vacuum monitoring device (vacuum gauge a) and the beam current variation curve of the standard ion pump after 10 hours of continuous operation under an electron microscope are as follows: Figure 7 As shown in the figure, the reading of the vacuum monitoring device (vacuum gauge a) jumped between 300 min and 400 min. If the actual vacuum level jumps, it will inevitably affect the beam current (because when the vacuum level decreases, the number of gas molecules remaining in the electron gun increases. These gas molecules collide with the electron beam, which may lead to electron beam scattering and the generation of secondary electrons, thus increasing the beam current intensity). However, the beam current did not change significantly during this period. That is, the reading of the vacuum monitoring device (vacuum gauge a) does not match the actual vacuum level change. In other words, the jump in the reading of the vacuum monitoring device (vacuum gauge a) may be caused by the local accumulation of gas molecules (at the vacuum gauge installation location), or it may be caused by changes in the electrical properties of the vacuum gauge itself (cathode, grid, collector) after long-term operation.

[0091] In addition, such as Figure 7 As shown, the readings of the vacuum gauge are similar from 450 min to 600 min, which means that the vacuum level of the electron gun does not change significantly during this period. However, from the perspective of the beam current, the beam intensity increases significantly around 520 min, which means that the vacuum level of the electron gun actually decreases significantly. It can be seen that the vacuum stability of the ion pump can be directly characterized based on the electron gun emission beam, and the characterization effect is better than that of the high-precision vacuum gauge.

[0092] In summary, the electron microscopy-based ion pump testing method according to the embodiments of the present invention can characterize the vacuum stability of the ion pump based on the beam parameters of the electron gun emitted beam, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0093] Specifically, this embodiment of the invention also proposes an ion pump testing method based on electron microscopy imaging applied to the aforementioned ion pump testing system 1000 based on electron microscopy imaging, such as... Figure 8 As shown, it includes:

[0094] S201, place the standard sample into the sample chamber, and connect at least two standard ion pumps from multiple ion pump groups to the vacuum chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to the first vacuum environment.

[0095] It is understood that in this embodiment of the present invention, a standard sample is placed in the sample chamber, and both the electron gun vacuum chamber and the sample chamber are connected to a standard ion pump until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes, thereby evacuating the sample chamber and the electron gun vacuum chamber to the first vacuum environment.

[0096] S202, select the target site in the first image under electron microscopy imaging, and control the emitted beam to remain constant.

[0097] It is understood that, in this embodiment of the present invention, identifiable feature sites with clear boundaries are selected from the electron microscope image as the first image target sites (e.g., Figure 9 As shown, the contact point between the large and small particles at the intersection of the horizontal and vertical lines is taken as the first image target point, and the emitted beam is controlled to remain constant. For example, the emitted beam parameters (beam current, voltage of each electrode lens, etc.) are controlled to remain at preset values.

[0098] S203, obtain the image drift value of the first image target site within a preset time period, and form the image drift curve of the corresponding standard ion pump.

[0099] It is understood that, in this embodiment of the present invention, by recording the initial coordinates of the pixel position of the first image target site at the beginning of the preset time (the intersection of the horizontal and vertical lines) within a preset time, and then recording the offset coordinates of the pixel position of the first image target site at the end of the preset time, the distance between the initial coordinates of the pixel position and the offset coordinates of the pixel position is calculated as the image drift value of the first image target site within the preset time period. Alternatively, by recording the coordinate trajectory of the first image target site within the preset time period, the farthest distance between the coordinate trajectory and the initial coordinates of the pixel position within the preset time period is obtained as the image drift value of the first image target site within the preset time period. Then, based on the aforementioned pixel offset value, an image drift curve of the corresponding standard ion pump changing with time is formed.

[0100] S204, connect at least two of the ion pumps to be tested from multiple ion pump groups to the vacuum chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to the first vacuum environment.

[0101] It is understood that in this embodiment of the present invention, both the electron gun vacuum chamber and the sample chamber are connected to the ion pump to be tested until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes, so that the sample chamber and the electron gun vacuum chamber are evacuated to the first vacuum environment.

[0102] S205, select the target site in the second image under electron microscopy imaging, and control the emitted beam to remain constant.

[0103] It is understood that in this embodiment of the present invention, identifiable feature sites with clear boundaries are selected as second image target sites in the image under electron microscopy imaging, and the emission beam is controlled to remain unchanged, for example, the emission beam parameters (beam current, voltage of each electrode lens, etc.) are controlled to remain at a preset value.

[0104] S206, obtain the image drift value of the target site in the second image within a preset time period, and form the image drift curve of the corresponding ion pump to be tested.

[0105] It is understood that, in this embodiment of the present invention, by recording the initial pixel coordinates (the intersection of the horizontal and vertical lines) of the second image target site at the beginning of the preset time within a preset time, and then recording the pixel position offset coordinates of the second image target site at the end of the preset time, the distance between the initial pixel position coordinates and the pixel position offset coordinates is calculated as the image drift value of the second image target site within the preset time period. Alternatively, by recording the coordinate trajectory of the second image target site within the preset time period, the farthest distance between the coordinate trajectory and the initial pixel position coordinates within the preset time period is obtained as the image drift value of the second image target site within the preset time period. Then, based on the aforementioned pixel offset value, an image drift curve of the corresponding standard ion pump changing with time is formed.

[0106] S207 characterizes the vacuum stability of each ion pump group based on the image drift curve of the corresponding standard ion pump and the image drift curve of the corresponding ion pump under test, so as to realize the comparative test of vacuum stability of multiple ion pump groups.

[0107] It is understood that, in this embodiment of the present invention, by comparing the image drift curves obtained in step S203 and step S206, the vacuum stability of different ion pumps can be compared, thereby achieving vacuum stability testing of at least one ion pump under test.

[0108] The following is combined Figure 10 The specific embodiments of the present invention will be described to illustrate the testing results of the ion pump testing method based on electron microscopy imaging.

[0109] Specifically, the readings and image drift curves of the vacuum monitoring device (vacuum gauge a) for a standard ion pump operating continuously for 10 hours in an electron microscope are as follows: Figure 10 As shown, the unit of reading for the vacuum monitoring device (vacuum gauge a) is 10. -8Pa, corresponding to the left vertical axis, represents the image drift value, which is the farthest distance between the target location's coordinate trajectory and its initial coordinates within a 10-minute time period, measured in nm, and corresponds to the right vertical axis.

[0110] Combination Figure 10 It is known that during the 10-hour continuous operation of the scanning electron microscope, the vacuum gauge reading jumped between 300 and 400 minutes. If the actual vacuum level jumps, it will inevitably affect the image offset value (when the vacuum level decreases, the number of gas molecules remaining in the electron gun increases, and these gas molecules collide with the electron beam, which may cause the electron beam to be unstable, thus increasing the image offset value). However, the image offset value did not change significantly during this period. In other words, the reading of the vacuum monitoring device (vacuum gauge a) does not match the actual change in vacuum level. The possible reasons for the jump in the reading of the vacuum monitoring device (vacuum gauge a) have been explained above and will not be repeated here.

[0111] In addition, such as Figure 10 As shown, the readings of the vacuum monitoring device (vacuum gauge a) are similar after the jump, which means that the vacuum level of the electron gun does not change significantly during this period. However, judging from the image offset value, the image offset value gradually increases, which means that the vacuum level of the electron gun has actually decreased significantly. This is consistent with the response to beam change. It can be seen that the vacuum stability of the ion pump can also be intuitively characterized based on image drift, and the characterization effect is better than that of high-precision vacuum gauges.

[0112] In summary, the electron microscopy-based ion pump testing method according to the embodiments of the present invention can characterize the vacuum stability of the ion pump based on the image drift curve, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups.

[0113] Specifically, this embodiment of the invention also proposes an ion pump testing method based on electron microscopy imaging applied to the aforementioned ion pump testing system 1000 based on electron microscopy imaging, such as... Figure 11 As shown, the method includes:

[0114] S301, place the standard sample into the sample chamber, and connect at least two standard ion pumps from multiple ion pump groups to the vacuum chamber, so that the sample chamber and the vacuum chamber of the electron gun are evacuated to a second vacuum environment.

[0115] It is understood that in this embodiment of the present invention, a standard sample is placed in the sample chamber, and both the electron gun vacuum chamber and the sample chamber are connected to a standard ion pump until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes, so that the sample chamber and the electron gun vacuum chamber are evacuated to a second vacuum environment.

[0116] S302, acquire the first image spur parameters of the corresponding standard ion pump under electron microscopy imaging.

[0117] Understandably, measurements can be made by measuring electron microscopy images formed based on standard ion pumps, such as... Figure 12 The image shows the burr length, and is obtained at a fixed magnification as shown. Figure 13 and Figure 14 The image shown clearly displays the frequency (density) of the image glitch, thus obtaining the first image glitch parameters corresponding to the standard ion pump under electron microscopy imaging.

[0118] S303 connects at least two of the ion pumps to be tested from multiple ion pump groups to the vacuum chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to a second vacuum environment.

[0119] It is understood that in this embodiment of the present invention, both the electron gun vacuum chamber and the sample chamber are connected to the ion pump to be tested until the reading of the vacuum monitoring device (vacuum gauge a) stabilizes, so that the sample chamber and the electron gun vacuum chamber are evacuated to a second vacuum environment.

[0120] S304, acquire the spur parameters of the second image of the ion pump under test under electron microscopy imaging.

[0121] Understandably, by measuring the length of the image burrs under an electron microscope image formed based on the ion pump under test, and obtaining an image that can clearly show the frequency (density) of the image burrs at a fixed magnification, the second image burr parameters corresponding to the ion pump under test under electron microscope imaging are obtained.

[0122] S305 characterizes the magnetic leakage of each ion pump group based on the first image burr parameters of the corresponding standard ion pump and the second image burr parameters of the corresponding ion pump under test, so as to realize the magnetic leakage comparison test of multiple ion pump groups.

[0123] It is understood that, in this embodiment of the present invention, by comparing the image glitch parameters obtained in step S302 and step S304, the leakage magnetic field of different ion pumps can be compared, thereby realizing the leakage magnetic field comparison test of at least one ion pump under test.

[0124] The following is combined Figure 13 and Figure 14 The test results of the ion pump testing method based on electron microscopy imaging in the present invention will be described in accordance with specific embodiments of the present invention.

[0125] Specifically, in combination Figure 13 and Figure 14It can be seen that the burr length and frequency of the ion pump under test are significantly better than those of the standard ion pump. In other words, the magnetic leakage of the ion pump under test is better than that of the standard ion pump. It can be seen that the magnetic leakage of the ion pump can be intuitively characterized based on the image burr and has good discrimination.

[0126] In summary, the ion pump testing method based on electron microscopy imaging according to the embodiments of the present invention can characterize the magnetic leakage of the ion pump based on image spur parameters, and the test results are more objective and accurate, enabling the testing of the magnetic leakage of multiple ion pump groups.

[0127] Based on the electron microscopy-based ion pump testing method of the foregoing embodiments of the present invention, the present invention also proposes a computer storage medium storing an electron microscopy-based ion pump testing program thereon. When the electron microscopy-based ion pump testing program is executed by a processor, it implements the electron microscopy-based ion pump testing method of the foregoing embodiments of the present invention.

[0128] It should be understood that...

[0129] In summary, the computer-readable storage medium according to embodiments of the present invention, by executing an ion pump test program based on electron microscopy imaging, can characterize the vacuum stability of the ion pump based on the beam parameters of the electron gun emitted beam, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups; or, it can characterize the vacuum stability of the ion pump based on image drift curves, and the test results are more objective and accurate, enabling comparative testing of the vacuum stability of multiple ion pump groups; or, it can characterize the magnetic leakage of the ion pump based on image burr parameters, and the test results are more objective and accurate, enabling testing of the magnetic leakage of multiple ion pump groups.

[0130] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0131] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0132] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0133] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0134] Furthermore, 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0135] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0136] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0137] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An electron microscope imaging based ion pump testing system, characterized by, The system includes: The sample chamber is suitable for placing samples for electron microscopy imaging; An electron gun, adapted to act on the electron microscope imaging sample by means of a beam of charged particles; A mechanical pump assembly, comprising a mechanical pump and a molecular pump, is adapted to evacuate the sample chamber and the electron gun vacuum chamber to a pre-vacuum environment. A molecular sieve suction pump is suitable for evacuating the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, wherein the vacuum degree of the ultra-high vacuum environment is greater than that of the pre-vacuum environment. Multiple ion pump sets, each including at least one standard ion pump and at least one ion pump under test, are suitable for comparative testing of the vacuum stability of ion pumps. A vacuum monitoring device is suitable for monitoring and displaying the vacuum levels of the sample chamber and the electron gun vacuum chamber; A beam monitoring device is adapted to monitor the emitted beam of the electron gun to obtain beam parameters, which are used to characterize the vacuum stability of each ion pump group, so as to realize the vacuum stability test of at least one ion pump.

2. The electron-microscope-imaging-based ion pump testing system of claim 1, wherein, The beam monitoring device includes: A charged particle beam emission source, wherein the charged particle beam emission source is connected to a high-voltage cathode and is suitable for generating charged particles; The extraction electrode includes a first anode and a second anode. The first anode is connected to a high-voltage anode and is adapted to extract the charged particles to form the emission beam. The upper end of the second anode is disposed corresponding to the lower end of the first anode, and the second anode is adapted to focus the emission beam. A first galvanometer is connected to the first anode and is adapted to monitor the lead-out current of the first anode; The power control module is adapted to adjust the voltage of the first anode and acquire the monitoring signal corresponding to the lead current of the first ammeter. The signal analysis module is adapted to generate the beam parameters based on the monitoring signal corresponding to the lead-out current of the first ammeter.

3. The electron-microscope-imaging-based ion pump testing system of claim 2, wherein, The lower end of the first anode has a funnel-shaped opening, and the upper end of the second anode has a funnel-shaped opening.

4. The ion pump testing system based on electron microscopy imaging according to claim 2, characterized in that, The beam monitoring device also includes: A second galvanometer is connected to the charged particle beam emission source and is adapted to monitor the emission current of the charged particle beam emission source; The power control module is also adapted to adjust the voltage of the second anode and acquire the monitoring signal corresponding to the emission current of the second ammeter; The signal analysis module is also adapted to generate the beam parameters based on the monitoring signal corresponding to the lead-out current of the first ammeter and the monitoring signal corresponding to the emission current of the second ammeter.

5. The ion pump testing system based on electron microscopy imaging according to claim 4, characterized in that, The signal analysis module is also adapted to, Frequency domain analysis is performed on the monitoring signal corresponding to the lead current of the first ammeter and the monitoring signal corresponding to the transmission current of the second ammeter to find the first frequency band with similar frequency domain signals. By adjusting the voltages of the first anode and the second anode, the stability of the first frequency band portion of the monitoring signal corresponding to the lead current of the first ammeter is optimized. The monitoring signals from the first ammeter and the second ammeter are collected, and the monitoring signal corresponding to the lead current of the first ammeter is superimposed in reverse with the monitoring signal corresponding to the lead current of the second ammeter to generate the beam current parameters.

6. The ion pump testing system based on electron microscopy imaging according to claim 1, characterized in that, The at least one standard ion pump and the at least one test ion pump are connected to the sample chamber or the electron gun vacuum chamber via a Y-shaped tee pipe.

7. The ion pump testing system based on electron microscopy imaging according to claim 1, characterized in that, The electron microscope is a transmission electron microscope or a scanning electron microscope.

8. A method for testing ion pumps based on electron microscopy imaging, characterized in that, The method, applied to the ion pump testing system based on electron microscopy imaging as described in any one of claims 1-5, comprises: The mechanical pump group is controlled to operate at a preset speed to evacuate the sample chamber and the electron gun vacuum chamber to a pre-vacuum environment; Connect the molecular sieve suction pump to the electron gun vacuum chamber to evacuate the sample chamber and the electron gun vacuum chamber to an ultra-high vacuum environment, and record the current reading of the vacuum monitoring device; At least two standard ion pumps from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, and the molecular sieve gas pump is disconnected to achieve vacuum stability testing of the at least two standard ion pumps; The emission beam of the electron gun is monitored to obtain the beam parameters corresponding to the standard ion pump. The beam parameters corresponding to the standard ion pump are used to characterize the vacuum stability of the at least two standard ion pumps. Disconnect at least two standard ion pumps from the plurality of ion pump groups to restore the sample chamber and the electron gun vacuum chamber to the pre-emptive vacuum environment; The molecular sieve suction pump is connected to the electron gun vacuum chamber again, so that the sample chamber and the electron gun vacuum chamber are evacuated to an ultra-high vacuum environment, and the current reading of the vacuum monitoring device is corrected. At least two of the ion pumps to be tested from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, and the molecular sieve gas pump is disconnected, so as to realize the vacuum stability test of the at least two ion pumps to be tested. The emission beam of the electron gun is monitored to obtain the beam parameters corresponding to the ion pump under test. The beam parameters corresponding to the ion pump under test are used to characterize the vacuum stability of the at least two ion pumps under test. Based on the beam parameters corresponding to the standard ion pump and the beam parameters corresponding to the ion pump under test, the vacuum stability test of at least one ion pump is achieved.

9. A method for testing ion pumps based on electron microscopy imaging, characterized in that, The method, applied to the ion pump testing system based on electron microscopy imaging as described in any one of claims 1-5, comprises: A standard sample is placed into the sample chamber, and at least two standard ion pumps from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to a first vacuum environment. Select the first target site in the electron microscope imaging and keep the emitted beam constant; The image drift value of the first image target site within a preset time period is obtained, and the corresponding image drift curve of the standard ion pump is generated. At least two of the ion pumps to be tested from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to the first vacuum environment; Select the target site in the second image obtained from electron microscopy imaging, and keep the emitted beam constant. The image drift value of the second image target site within a preset time period is obtained, and the corresponding image drift curve of the ion pump to be tested is formed; The vacuum stability of each ion pump group is characterized by the image drift curve of the corresponding standard ion pump and the image drift curve of the corresponding ion pump under test, so as to realize the comparative test of the vacuum stability of the multiple ion pump groups.

10. A method for testing ion pumps based on electron microscopy imaging, characterized in that, The method, applied to the ion pump testing system based on electron microscopy imaging as described in any one of claims 1-5, comprises: A standard sample is placed into the sample chamber, and at least two standard ion pumps from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to a second vacuum environment; Obtain the glitch parameters of the first image of the corresponding standard ion pump under electron microscopy imaging; At least two of the ion pumps to be tested from the plurality of ion pump groups are connected to the electron gun vacuum chamber and the sample chamber, so that the sample chamber and the electron gun vacuum chamber are evacuated to the second vacuum environment; Obtain the spur parameters of the second image of the ion pump under test under electron microscopy imaging; The leakage magnetic field of each ion pump group is characterized by the first image burr parameters of the corresponding standard ion pump and the second image burr parameters of the corresponding ion pump under test, so as to realize the comparative test of leakage magnetic field of the multiple ion pump groups.

11. A computer storage medium, characterized in that, It stores an ion pump testing program based on electron microscopy imaging, which, when executed by a processor, implements the ion pump testing method based on electron microscopy imaging according to any one of claims 8-10.

Images