A test power supply system for an electron beam device

Abstract

This invention discloses a test power supply system for an electron beam device, comprising: a power supply module; the power supply module includes a main control unit, a slave control unit, an accelerating electrode power supply circuit, a suppressor electrode power supply circuit, a filament power supply circuit, and a beam current sampling circuit; the main control unit controls the accelerating electrode power supply circuit to output a first adjustable voltage to the accelerating electrode of the electron gun, and outputs a set parameter execution command to the slave control unit; the slave control unit controls the suppressor electrode power supply circuit to output a second adjustable voltage to the suppressor electrode of the electron gun; the slave control unit also controls the filament power supply circuit to output a first adjustable current to the filament of the electron gun according to the second set parameter execution command; the beam current sampling circuit is electrically connected to the accelerating electrode power supply circuit and the accelerating electrode, respectively, for acquiring the electron beam current and sending it to the main control unit. The technical solution provided by this invention can improve the accuracy of electron beam current detection of the filament.

Description

Technical Field

[0001] This invention relates to the field of electron microscopy, and more particularly to a test power supply system for an electron beam device. Background Technology

[0002] Electron microscopes, represented by transmission electron microscopes and scanning electron microscopes, are important tools for humankind to explore the microscopic world. They are widely used in many fields such as materials science, life sciences, semiconductor industry, geology, energy, medicine, and pharmaceuticals, playing a significant role in human scientific research and industrial production.

[0003] The core component of a transmission electron microscope (TEM) is the electron gun, whose performance directly determines the microscope's resolution and imaging quality. A commonly used field emission electron gun (FEG) consists of a filament, a suppressor electrode, and an accelerating electrode. After the filament is fabricated, its emission characteristics (such as emission current, stability, and lifetime) must be accurately measured and evaluated. This process requires a high-precision dedicated power supply system. However, in current technology, different universal power supplies are used to independently power the filament, suppressor electrode, and accelerating electrode. The poor power supply stability of universal power supplies leads to large fluctuations in filament measurement data, making it impossible to accurately evaluate filament performance. Summary of the Invention

[0004] This invention provides a test power supply system for an electron beam device to improve the accuracy of electron beam current detection in a filament.

[0005] In a first aspect, embodiments of the present invention provide a test power supply system for an electron beam device, comprising: at least one power supply module; the power supply module includes at least a master control unit, a slave control unit, an accelerating electrode power supply circuit, a suppressing electrode power supply circuit, a filament power supply circuit, and a beam sampling circuit;

[0006] The main control unit is electrically connected to the accelerating electrode power supply circuit and is used to control the accelerating electrode power supply circuit to output a first adjustable voltage to the accelerating electrode of the electron gun; the main control unit is also used to output a setting parameter execution instruction to the slave control unit; the setting parameter execution instruction includes at least a first setting parameter execution instruction and a second setting parameter execution instruction;

[0007] The slave control unit is used to execute instructions according to the first set parameters to control the suppression electrode power supply circuit to output a second adjustable voltage to the suppression electrode of the electron gun; the slave control unit is also used to execute instructions according to the second set parameters to control the filament power supply circuit to output a first adjustable current to the filament of the electron gun;

[0008] The beam sampling circuit is electrically connected to the accelerating electrode power supply circuit and the accelerating electrode, respectively, and is used to acquire the electron beam current and send it to the main control unit.

[0009] In this invention, the power supply module includes a master control unit and a slave control unit. The master control unit controls the accelerating electrode power supply circuit to generate a first adjustable voltage and supply power to the accelerating electrode of the electron gun in the electron beam device; the slave control unit controls the suppressor power supply circuit to generate a second adjustable voltage and supply power to the suppressor of the electron gun; the slave control unit can also control the filament power supply circuit to generate a first adjustable current and transmit it to the filament of the electron gun. The master control unit outputs a setting parameter execution command to the slave control unit, so that the slave control unit controls the generation of the second adjustable voltage according to the first setting parameter execution command and controls the generation of the first adjustable current according to the second setting parameter execution command. In addition, a beam current sampling circuit is disposed between the accelerating electrode power supply circuit and the accelerating electrode, and is used to obtain the electron beam current from the output terminal of the accelerating electrode power supply circuit and send it to the master control unit. In this embodiment, the main control unit can control and adjust the accelerating electrode power supply circuit, the suppressor power supply circuit, and the filament power supply circuit to obtain stable first adjustable voltage, second adjustable voltage, and first adjustable current. This ensures stable power supply to the electron gun, thereby obtaining a stable electron beam current. This allows for precise detection of the electron beam current emitted by the filament, accurate evaluation of the filament performance, and enhanced reliability of the electron beam measurement. Furthermore, the measurement process does not rely on manual operation and recording, avoiding errors caused by manual operation. This effectively solves the problems of poor repeatability and low efficiency in beam current measurement, enabling rapid and batch filament testing. Attached Figure Description

[0010] Figure 1 A schematic diagram of the structure of a test power supply system for an electron beam device provided in an embodiment of the present invention;

[0011] Figure 2 This is a schematic diagram of the power supply module provided in an embodiment of the present invention;

[0012] Figure 3 This is a schematic diagram of another power supply module provided in an embodiment of the present invention;

[0013] Figure 4 A schematic diagram of the electron beam current detection circuit for a filament provided in an embodiment of the present invention;

[0014] Figure 5 A control flowchart of a test power supply system for an electron beam device is provided as an embodiment of the present invention;

[0015] Figure 6 This is a schematic diagram of the structure of an accelerating electrode power supply circuit provided in an embodiment of the present invention;

[0016] Figure 7 This is a schematic diagram of a suppression electrode power supply circuit provided in an embodiment of the present invention;

[0017] Figure 8This is a schematic diagram of a filament power supply circuit provided in an embodiment of the present invention. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0019] As the application of scanning electron microscopy (SEM) in scientific research continues to increase, the demands on SEM technology are also becoming more sophisticated. When using SEM for sample analysis, different beam currents have a significant impact on the scanned sample. For example, some electron beam-sensitive metal-organic framework (MOF) materials require low beam current scanning, while some semiconductor samples require high beam current scanning. In electron backscattered electron diffraction (EBSD) analysis, beam current also affects resolution and quantitative accuracy. Therefore, determining the appropriate beam current is crucial for sample analysis.

[0020] An electron beam is a stream of electrons moving directionally with a small divergence, typically emitted by an electron gun. Electron beam technology has applications in various fields, such as materials processing, electron microscopy, and semiconductor device manufacturing. The core component of an electron beam device (e.g., an electron microscope) is the electron gun, whose performance directly determines the microscope's resolution and imaging quality. A commonly used field emission electron gun (FEG) consists of a filament, a suppressor electrode, and an accelerating electrode. In implementing embodiments of this invention, the inventors discovered that measuring emission performance (such as emission beam current, stability, and lifetime) requires a high-precision dedicated power supply system. However, in existing technologies, the filament, suppressor electrode, and accelerating electrode are independently powered by different general-purpose power supplies. This results in poor power supply stability for the electron gun and a lack of precise matching and coordinated control among the components. Consequently, electron beam measurements suffer from poor repeatability and low efficiency, excessive reliance on manual operation and recording, cumbersome procedures, and a high risk of human error, making rapid, batch filament testing impossible.

[0021] To address the above problems, embodiments of the present invention provide a test power supply system for an electron beam device, such as... Figure 1 and Figure 2 As shown, Figure 1 This is a schematic diagram of the structure of a test power supply system for an electron beam device provided in an embodiment of the present invention. Figure 2The schematic diagram of the power supply module provided in the embodiment of the present invention shows that the test power supply system of the electron beam equipment may include: at least one power supply module 10; the power supply module 10 includes at least a master control unit 11, a slave control unit 12, an accelerating electrode power supply circuit 13, a suppressing electrode power supply circuit 14, a filament power supply circuit 15, and a beam sampling circuit 16.

[0022] The main control unit 11 is electrically connected to the accelerating electrode power supply circuit 13 and is used to control the accelerating electrode power supply circuit 13 to output a first adjustable voltage to the accelerating electrode 31 of the electron gun 30; the main control unit 11 is also used to output a setting parameter execution command to the slave control unit 12; the setting parameter execution command includes at least a first setting parameter execution command and a second setting parameter execution command.

[0023] The slave control unit 12 is used to execute instructions according to the first set parameters to control the suppressor power supply circuit 14 to output a second adjustable voltage to the suppressor 32 of the electron gun 30; the slave control unit 12 is also used to execute instructions according to the second set parameters to control the filament power supply circuit 15 to output a first adjustable current to the filament 33 of the electron gun 30.

[0024] The beam sampling circuit 16 is electrically connected to the accelerating electrode power supply circuit 13 and the accelerating electrode 31, respectively, and is used to acquire the electron beam current and send it to the main control unit 11.

[0025] like Figure 1 As shown, the test power system of the electron beam device in this embodiment may include at least one power supply module 10, and each power supply module 10 can provide test power to the corresponding electron gun 30. For example, Figure 1 Taking the test power system of each electron beam device as an example, which includes three power supply modules 10, the test power system of each electron beam device can simultaneously perform beam current detection for three different electron beam devices, effectively improving the efficiency of electron gun performance testing.

[0026] The electron gun 30 is a device for generating, accelerating, and focusing a high-energy-density electron beam. It includes a filament 33, a suppressor 32, and an accelerating electrode 31. The filament 33 typically uses tungsten wire heating to generate thermionic electrons. These thermionic electrons are accelerated towards the accelerating electrode 31 under high voltage control between the accelerating electrode 31 and the filament 33, forming the electron beam. The suppressor 32 is used to focus the electron beam. Figure 2As shown, each power supply module 10 includes an accelerating electrode power supply circuit 13, a suppressor power supply circuit 14, and a filament power supply circuit 15. The accelerating electrode power supply circuit 13 is electrically connected to the accelerating electrode 31 of the corresponding electron gun 30, and is used to provide a first adjustable voltage to the accelerating electrode 31; the suppressor power supply circuit 14 is electrically connected to the suppressor electrode 32 of the corresponding electron gun 30, and is used to provide a second adjustable voltage to the suppressor electrode 32; the filament power supply circuit 15 is electrically connected to the filament 33 of the corresponding electron gun 30, and is used to provide a first adjustable current to the filament 33. The power supply module 10 is also provided with a master control unit 11 and a slave control unit 12. The master control unit 11 is used to control the accelerating electrode power supply circuit 13 to output the first adjustable voltage, and the slave control unit 12 can control the suppressor power supply circuit 14 to output the second adjustable voltage and control the filament power supply circuit 15 to output the first adjustable current. Under the control of the master control unit 11, the slave control unit 12 controls the suppressor power supply circuit 14 and the filament power supply circuit 15 respectively, so that the suppressor power supply circuit 14 and the filament power supply circuit 15 output corresponding output signals. Specifically, the master control unit 11 sends a setting parameter execution command to the slave control unit 12. The setting parameters may include parameters such as a second adjustable voltage and a first adjustable current. The second adjustable voltage is the suppressor voltage of the suppressor 32 of the electron gun 30, and the first adjustable current is the filament current of the filament 33 of the electron gun 30. In addition, if the slave control unit 12 needs to control more power supply circuits, the setting parameters may also be other parameters, which are not specifically limited in this embodiment. In this embodiment, the setting parameter execution command may include at least a first setting parameter execution command and a second setting parameter execution command. The slave control unit 12 can control the suppressor power supply circuit 14 to generate the second adjustable voltage according to the first setting parameter execution command, and the slave control unit 12 can also control the filament power supply circuit 15 to generate the first adjustable current according to the second setting parameter execution command.

[0027] Furthermore, it should be noted that the power supply module 10 may also include a beam sampling circuit 16. A beam sampling circuit 16 is provided between the power supply lines of the accelerating electrode power supply circuit 13 and the accelerating electrode 31. The beam sampling circuit 16 can collect the electron beam current corresponding to the electron beam, thereby acquiring the state of the electron beam. The power supply module provided in this embodiment can accurately detect the electron beam of the electron gun 30. This embodiment includes a related master control unit 11 and slave control unit 12. The master control unit 11 directly controls the accelerating electrode power supply circuit 13, and the slave control unit 12, under the control of the master control unit 11, controls the suppressor power supply circuit 14 and the filament power supply circuit 15. That is, this embodiment achieves direct or indirect control of the accelerating electrode power supply circuit 13, the suppressor power supply circuit 14, and the filament power supply circuit 15 through the master control unit 11. This enables coordinated control and communication of the output signals of each power supply circuit, achieving precise parameter matching and rapid linkage adjustment, resulting in excellent repeatability and high efficiency in electron beam measurement. Compared to existing general-purpose power supplies, the accelerating electrode power supply circuit 13, the suppressing electrode power supply circuit 14, and the filament power supply circuit 15 exhibit stronger stability, resulting in more stable measurement data and allowing for accurate evaluation of filament performance. Furthermore, because this embodiment utilizes the main control unit 11 to detect the beam circuit, manual operation and recording are unnecessary, saving cumbersome labor costs and reducing human error. Additionally, as... Figure 1 As shown, the test power system of an electron beam device can be equipped with multiple power supply modules 10, thereby enabling simultaneous beam current detection for multiple electron guns 30, achieving rapid and batch filament testing.

[0028] In this embodiment of the invention, the power supply module includes a master control unit and a slave control unit. The master control unit can control the accelerating electrode power supply circuit to generate a first adjustable voltage and supply power to the accelerating electrode of the electron gun in the electron beam device; the slave control unit can control the suppressor power supply circuit to generate a second adjustable voltage and supply power to the suppressor of the electron gun; the slave control unit can also control the filament power supply circuit to generate a first adjustable current and transmit it to the filament of the electron gun. The master control unit outputs a setting parameter execution command to the slave control unit, so that the slave control unit controls the generation of the second adjustable voltage according to the first setting parameter execution command and controls the generation of the first adjustable current according to the second setting parameter execution command. In addition, a beam current sampling circuit is disposed between the accelerating electrode power supply circuit and the accelerating electrode, and is used to obtain the electron beam current from the output terminal of the accelerating electrode power supply circuit and send it to the master control unit. In this embodiment, the main control unit can control and adjust the accelerating electrode power supply circuit, the suppressor power supply circuit, and the filament power supply circuit to obtain stable first adjustable voltage, second adjustable voltage, and first adjustable current. This ensures stable power supply to the electron gun, thereby obtaining a stable electron beam current. This allows for precise detection of the electron beam current emitted by the filament, accurate evaluation of the filament performance, and enhanced reliability of the electron beam measurement. Furthermore, the measurement process does not rely on manual operation and recording, avoiding errors caused by manual operation. This effectively solves the problems of poor repeatability and low efficiency in beam current measurement, enabling rapid and batch filament testing.

[0029] The above is the core idea of ​​this invention. The technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0030] Figure 3This is a schematic diagram of another power supply module provided in an embodiment of the present invention. Optionally, the test power supply system of the electron beam equipment may further include: a host computer 20; the host computer 20 is electrically connected to the main control unit 11 and is used to send setting parameter commands to the main control unit 11; the main control unit 11 is used to control the accelerating electrode power supply circuit 13 and the slave control unit 12 according to the setting parameter commands; the host computer 20 is also used to receive the electron beam current sent by the main control unit 11, and adjust the electron beam current through the main control unit 11 when the difference between the electron beam current and the set beam current threshold exceeds a first difference. In this embodiment, the host computer 20 can send setting parameter commands to the main control unit 11. The setting parameters here can be a first adjustable voltage, a second adjustable voltage, and a first adjustable current, that is, the accelerating electrode voltage, the suppressing electrode voltage, and the filament current. The main control unit 11 controls the main control layer devices (e.g., the accelerating electrode power supply circuit 13) according to the set parameter instructions and the actual working scenario of the electron source (e.g., different filament materials, different beam current requirements, etc.), and sends the set parameter execution instructions to the slave control unit 12 so that the slave control unit 12 controls the slave control layer devices (the suppressor power supply circuit 14 and the filament power supply circuit 15). The main control unit 11 is also used to acquire the electron beam current through the beam current sampling circuit 16 and transmit it to the host computer 20. The beam current sampling circuit 16 can collect the electron beam current in real time. When the difference between the electron beam current and the set beam current threshold exceeds a first difference value, the host computer 20 automatically triggers a linkage adjustment prompt. For example, it can analyze the reasons for the deviation between the electron beam current and the set beam current threshold and output the adjustment direction prompt. Based on this, the host computer 20 can automatically adjust the electron beam current or prompt the operator to manually input fine-tuning parameters and receive the operator's manually input instructions so that the difference between the electron beam current and the set beam current threshold is less than or equal to the first difference value. For example, when the difference between the electron beam current and the set beam current threshold exceeds a first difference, the host computer 20 can adjust the first adjustable voltage output by the accelerating electrode power supply circuit 13 to obtain the required electron beam current. In this embodiment, the acquisition accuracy of the electron beam current by the beam current sampling circuit 16 can be less than or equal to 1μA. Optionally, the range of the first difference can be -5%d to +5%d; d is the set beam current threshold. This embodiment can not only accurately measure the electron beam current, but also correct the deviation of the electron beam current in a timely manner when the difference between the electron beam current and the set beam current threshold is greater than the first difference, thereby improving the performance and reliability of the filament.

[0031] like Figure 2 As shown, the beam sampling circuit 16 can be set up independently, or, as... Figure 3 As shown, the beam sampling circuit can also be integrated inside the accelerating electrode power supply circuit 13. In this embodiment, the location of the beam sampling circuit 16 is not limited. Figure 4This is a schematic diagram of an electron beam current detection circuit for a filament provided in an embodiment of the present invention. Optionally, the beam sampling circuit 16 may include: a first resistor R1 and a first operational amplifier U1; the output terminal of the accelerating electrode power supply circuit 13 is electrically connected to the first input terminal of the first operational amplifier U1; the second input terminal of the first operational amplifier U1 is electrically connected to the accelerating electrode; the output terminal of the first operational amplifier U1 is electrically connected to the main control unit 11, used to convert the electron beam current into a beam voltage and transmit it to the main control unit 11; the first end of the first resistor R1 is electrically connected to the output terminal of the first operational amplifier U1; the second end of the first resistor R1 is electrically connected to the first input terminal of the first operational amplifier U1. In this embodiment, through hardware and software collaborative control, operators can easily complete the electron source testing work. This beam sampling circuit 16 can be located inside the accelerating electrode power supply circuit 13, mainly composed of a precision first resistor R1 and a precision first operational amplifier U1. The electron beam current i passes through the first resistor R1 and forms a voltage V at the output of the first operational amplifier U1, where V = i × R1. The beam sampling circuit 16 converts the acquired current signal into a voltage signal and sends it to the main control unit 11 for storage and analysis by the host computer 20. (Continue to refer to...) Figure 1 To improve the efficiency of electronic source performance testing, three power supply systems are provided, which are integrated and controlled by a host computer to achieve automated and visualized testing, solving the problems of cumbersome manual operation, easy introduction of human error, and inability to achieve rapid and batch testing.

[0032] Optionally, the slave control unit 12 can also be used to acquire the second adjustable voltage and the first adjustable current and send them to the master control unit 11; the master control unit 11 can also be used to acquire the first adjustable voltage; the host computer 20 can also be used to adjust the second adjustable voltage, the first adjustable voltage and the first adjustable current according to the corresponding set values.

[0033] In addition to controlling the output voltage or current of the main control layer devices (such as the accelerating electrode power supply circuit 13), the main control unit 11 can also receive real-time operating data fed back by the main control layer devices. If a deviation is found between the real-time operating data and the set parameters, it is fed back to the host computer 20. Specifically, the main control unit 11 can also be used to acquire the first adjustable voltage. When there is a deviation between the first adjustable voltage and the set value of the corresponding accelerating electrode voltage, it can be fed back to the host computer 20. The host computer 20 can adjust the first adjustable voltage according to the set program or the parameter commands input by the operator. Similarly, in addition to controlling the slave layer devices (suppressor power supply circuit 14 and filament power supply circuit 15), the slave control unit 12 can also collect the sampling signals of the suppressor voltage and filament current in real time and transmit them back to the master control unit 11. This ensures that the master control unit 11 can keep track of the operating status of each power supply module, such as the accelerating electrode power supply circuit 13, the suppressor power supply circuit 14, and the filament power supply circuit 15, in real time. At the same time, it strictly executes the parameter instructions issued by the master control layer, forming a closed loop of "instruction reception - parameter execution - data feedback". The response period is ≤50ms, ensuring the timeliness of parameter adjustment.

[0034] This embodiment adopts a "master-slave hierarchical control - multi-parameter linkage optimization" scheme, such as... Figure 5 As shown, Figure 5 This invention provides a control flowchart for a test power supply system of an electron beam device. The main control unit receives initial setting parameter commands (such as filament current (first adjustable current), accelerating electrode voltage (first adjustable voltage), and suppressor voltage (second adjustable voltage)) from the host computer. Combining this with the actual operating scenario of the electron source (such as filaments of different materials, different beam current requirements, etc.), it sends setting parameter execution commands to the slave control units. Simultaneously, it receives real-time operating data from the slave control layer devices. If a deviation is found between the parameters and the actual requirements, it feeds back to the host computer, prompting the operator to perform manual correction (such as manually adjusting the accelerating electrode voltage in the host computer based on the beam current detection results), thus resolving the potential compatibility issues of single automatic control.

[0035] Continue to refer to Figure 3Optionally, the test power supply system of the electron beam equipment may further include: a high-voltage isolation control unit 19; the high-voltage isolation control unit 19 is electrically connected to the main control unit 11 and the slave control unit 12 respectively, and is used to realize communication isolation between the main control unit 11 and the slave control unit 12. The high-voltage isolation control unit 19 is used to establish communication between the main control unit 11 and the slave control unit 12, and to realize isolated communication. For example, the high-voltage isolation control unit 19 can realize fiber optic transceiver communication and can realize an isolation voltage greater than 200kV. In this embodiment, the main control unit 11 is used to receive user instructions, control the output of each power module, process sampling data, execute protection logic, and realize automated measurement process; the slave control unit 12 communicates with the main control unit 11 through the high-voltage isolation control unit 19, the slave control unit 12 receives instructions issued by the main control unit 11, controls the operation of the suppressor power supply circuit 14 and the filament power supply circuit 15, and transmits the collected filament current and suppressor voltage to the main control unit 11.

[0036] Optionally, the test power supply system of the electron beam equipment may further include: a power supply unit 17 and a high-voltage isolation power supply unit 18; the power supply unit 17 is used to convert AC mains power into DC power and to power the main control unit 11 and the accelerating electrode power supply circuit 13; the high-voltage isolation power supply unit 18 is electrically connected to the power supply unit 17 and the slave control unit 12 respectively, and is used to realize power isolation between the main control unit 11 and the slave control unit 12; the high-voltage isolation power supply unit 18 is also used to power the suppressor power supply circuit 14 and the filament power supply circuit 15; the output terminal of the accelerating electrode power supply circuit 13 is electrically connected to the output terminal of the high-voltage isolation power supply unit 18.

[0037] Power supply unit 17 includes a live wire terminal (L), a neutral wire terminal (N), and a ground terminal (PE) for connection to the live, neutral, and protective ground wires of the mains power supply. It converts 220V AC mains power into +24V DC power to provide power to the entire test power system. High-voltage isolation power supply unit 18 uses solid-state packaging technology to convert the input +24V DC power into +24V DC power output via a high-frequency transformer, with an input-output isolation voltage of 50kV. Figure 3As shown, the output terminal of the accelerating electrode power supply circuit 13 is electrically connected to the output terminal of the high-voltage isolation power supply unit 18. Although the high-voltage isolation power supply unit 18 outputs 24V DC, the negative high voltage output by the accelerating electrode power supply circuit 13 also pulls the output terminal of the high-voltage isolation power supply unit 18 to a negative high voltage HT. The accelerating electrode power supply circuit 13 is connected to the main control unit 11, outputting an adjustable negative high voltage (0-30kV) to the accelerating electrode. The suppressor power supply circuit 14 is connected to the slave control unit 12, receiving the first set parameter execution command from it, and outputting an adjustable negative high voltage (0-1kV) to the suppressor. The filament power supply circuit 15 is connected to the slave control unit 12, receiving the second set parameter execution command from it, and providing a high-precision adjustable current (0-3A) to the filament. It should be noted that the main control unit 11 and the accelerating electrode power supply circuit 13 are powered by the power supply unit 17, which is the low-voltage part of the test power supply system; the slave control unit 12, the suppressor power supply circuit 14 and the filament power supply circuit 15 are powered by the high-voltage isolation power supply unit 18, which is the high-voltage part of the test power supply system.

[0038] Figure 6 This is a schematic diagram of an accelerating electrode power supply circuit provided in an embodiment of the present invention. Optionally, the accelerating electrode power supply circuit may include: a first converter 131, a first voltage doubler rectifier circuit 132, a first filter 133, and a second operational amplifier 134; the first converter 131 is electrically connected to the output terminal of the power supply unit 17 and is used to generate a first AC voltage; the first voltage doubler rectifier circuit 132 is electrically connected to the first converter 131 and is used to convert the first AC voltage into a first DC voltage; the first filter 133 is electrically connected to the first voltage doubler rectifier circuit 132 and is used to filter the first DC voltage to form a first adjustable voltage and output it through the output terminal of the first filter 133; the output terminal of the first filter 133 is grounded to GND through a first voltage regulating resistor R5 and a second voltage regulating resistor R6 in sequence; a first node N1 is formed between the first voltage regulating resistor R5 and the second voltage regulating resistor R6; the first input terminal of the second operational amplifier 134 is connected to the first set voltage of the main control unit 11; the second input terminal of the second operational amplifier 134 is connected to the first node N1; the output terminal of the second operational amplifier 134 is electrically connected to the control terminal of the first converter 131.

[0039] like Figure 6As shown, the main control unit 11 of the accelerating electrode power supply circuit is connected to a high-stability reference source. This high-stability reference source serves as a reference voltage, with a stability better than 5ppm / 10min, facilitating the output of a stable first set voltage. The main control unit 11 includes a main MCU and a digital-to-analog converter (DAC). The DAC converts the digital signal output from the main MCU into an analog signal, which is then fed to the second operational amplifier 134. The first converter 131 (including input terminals DC+ and DC-) converts the DC voltage output from the power supply unit 17 into a first AC voltage. The first voltage doubler rectifier circuit 132 converts the first AC voltage back to the first DC voltage. For example, the first converter 131 can be a Royer converter, which converts the DC voltage output from the power supply unit 17 into a standard sine wave. After being boosted by the first voltage doubler rectifier circuit 132, a stable and adjustable negative high voltage is output. The first voltage doubler rectifier circuit 132 utilizes the rectification and guiding effects of diodes to store the voltage in their respective capacitors, then connects them in series according to the principle of adding polarities, outputting a high voltage higher than the input voltage. The first voltage doubler rectifier circuit 132 may include a transformer T1, rectifier diodes D2 and D3, capacitors C1 and C2. When the first voltage doubler rectifier circuit 132 is in the positive half-cycle (positive half-cycle of a sine wave), rectifier diode D2 is turned on and rectifier diode D3 is turned off, and the current charges capacitor C1 through rectifier diode D2. When the first voltage doubler rectifier circuit 132 is in the negative half-cycle (negative half-cycle of a sine wave), rectifier diode D3 is turned on and rectifier diode D2 is turned off. At this time, the voltage on capacitor C1 is added in series with the first AC voltage, and the current charges capacitor C2 through rectifier diode D3, increasing the charging voltage. This charging process is repeated until the voltage on capacitor C2 is essentially the first DC voltage. Figure 6 The first voltage doubler rectifier circuit 132 shown is a voltage doubler rectifier circuit, where the first DC voltage is twice the first AC voltage, hence the name voltage doubler rectifier circuit. The first DC voltage is then filtered by the first filter 133 to form a first adjustable voltage, which is then output to the accelerating electrode. For example, the first filter 133 can be a three-stage RC filter network to achieve better filtering results. Figure 6 As shown, the first-stage RC filter circuit includes a filter resistor R1 and a filter capacitor C3; the second-stage RC filter circuit includes a filter resistor R2 and a filter capacitor C4; and the third-stage RC filter circuit includes a filter resistor R3 and a filter capacitor C5. The first voltage doubler rectifier circuit 132 and the first filter 133 ensure high stability and low ripple requirements for the output high voltage. For example, this embodiment can achieve a ripple coefficient ≤0.01%.

[0040] It should be noted that the accelerating electrode power supply circuit also includes voltage regulating resistors: a first voltage regulating resistor R5 and a second voltage regulating resistor R6. The connection point between the first voltage regulating resistor R5 and the second voltage regulating resistor R6 is the first node N1, which obtains the sampled accelerating electrode voltage of the first adjustable voltage. The second operational amplifier 134 can adjust the control signal output to the control terminal of the first converter 131 according to the difference between the first set voltage and the sampled accelerating electrode voltage, thereby realizing closed-loop feedback control of the first adjustable voltage. Optionally, the output terminal of the second operational amplifier 134 can be electrically connected to the first converter 131 through resistor R7. In addition, in this embodiment, the resistance ratio of the first voltage regulating resistor R5 and the second voltage regulating resistor R6 can be adjusted to adjust the value of the first adjustable voltage and obtain the first adjustable voltage to the accelerating electrode required by the operator. The accelerating electrode power supply circuit of this embodiment can adopt a "high-stability reference source + Royer converter + three-stage RC filter" combined architecture, which has the characteristics of low ripple and high stability.

[0041] Figure 7 This is a schematic diagram of a suppression electrode power supply circuit provided in an embodiment of the present invention. Similarly, optionally, the suppression power supply circuit may include: a third converter 141, a second voltage doubler rectifier circuit 142, a third filter 143, and a fourth operational amplifier 144; the third converter 141 is electrically connected to the output terminal of the high-voltage isolation power supply unit 18 to generate a second AC voltage; the second voltage doubler rectifier circuit 142 is electrically connected to the third converter 141 to convert the second AC voltage into a second DC voltage; the third filter 143 is electrically connected to the second voltage doubler rectifier circuit 142 to filter the first DC voltage to form a second adjustable voltage, which is then output through the output terminal of the third filter 143; the output terminal of the third filter 143 is grounded to HGND via a third voltage regulating resistor R51 and a fourth voltage regulating resistor R61; a second node N2 is formed between the third voltage regulating resistor R51 and the fourth voltage regulating resistor R61; the first input terminal of the fourth operational amplifier 144 is connected to the third set voltage of the slave control unit 12; the second input terminal of the fourth operational amplifier 144 is connected to the second node N2; and the output terminal of the fourth operational amplifier 144 is electrically connected to the control terminal of the third converter 141. The suppressor power supply circuit in this embodiment can adopt a combination architecture of "high-stability reference source + Royer converter + three-stage RC filter". The stability of the high-stability reference source is better than 5ppm / 10min. The Royer converter converts the DC voltage into a standard sine wave, which is boosted by the voltage doubler rectifier circuit and outputs a stable and adjustable negative high voltage with a ripple coefficient ≤0.01%, exhibiting the characteristics of low ripple and high stability.

[0042] Figure 8This is a schematic diagram of a filament power supply circuit provided in an embodiment of the present invention. Optionally, the filament power supply circuit 15 may include: a second converter 151, a second rectifier circuit 152, a second filter 153, a current differential sampling unit 154, and a third operational amplifier 155; the second converter 151 is electrically connected to the output terminal of the high-voltage isolation power supply unit 18 and is used to generate a first alternating current; the second rectifier circuit 152 is electrically connected to the second converter 151 and is used to convert the first alternating current into a first direct current; the second filter 153 is electrically connected to the second rectifier circuit 152 and is used to filter the first direct current to form a first adjustable current; a low-temperature drift resistor network 156 is provided between the second rectifier circuit 152 and the second filter 153; the two ends of the low-temperature drift resistor network 156 are connected to the current differential sampling unit 154; the current differential sampling unit 154 is used to convert the first direct current into a sampling voltage and transmit it to the second input terminal of the third operational amplifier 155; the first input terminal of the third operational amplifier 155 is connected to the second set voltage of the slave control unit 12; the output terminal of the third operational amplifier 155 is electrically connected to the control terminal of the second converter 151.

[0043] The slave control unit 12 of the filament power supply circuit 15 is connected to a high-stability reference source. This high-stability reference source serves as a reference voltage with a stability better than 5ppm / 10min, facilitating the output of stable second and third set voltages. The slave control unit 12 includes an MCU and a digital-to-analog converter (DAC). The DAC converts the digital signal output from the MCU into an analog signal, which is then fed to the third operational amplifier 155. The second converter 151 converts the DC power output from the high-voltage isolation power supply unit 18 into a first AC current. The second rectifier circuit 152 includes a transformer T2, rectifier diodes D1 and D4, used to convert the first AC current into a first DC current. The second filter 153 filters the first DC current to form a first adjustable current. The current differential sampling unit 154 acquires the first DC current and forms a sampling voltage through the two ends of the low-temperature drift resistor network 156. The third operational amplifier 155 controls the control terminal of the second converter 151 based on the difference between the sampling voltage and the second set voltage. Specifically, the third operational amplifier 155 can be electrically connected to the PWM drive module that controls the second converter 151 to indirectly control the output current state of the second converter 151. The filament power supply circuit adopts closed-loop feedback control to ensure that the filament current is not affected by the temperature coefficient of the filament resistance. The second filter 153 adopts dual LC filtering (filter inductor L2, filter capacitor C6, filter inductor L3, and filter capacitor C7), outputting a high-precision current of 0-3A, with a current stability ≤0.05% and ripple better than 10mA. This power supply also has the characteristics of low ripple and high stability.

[0044] Optionally, the test power supply system of the electron beam equipment may also include: a human-machine interface unit; the human-machine interface unit includes a touch screen 21 and a host computer interface; the touch screen 21 is used to receive setting parameters input by the user; the host computer interface is used to display the electron beam current, the first adjustable voltage, the second adjustable voltage, and the first adjustable current. The human-machine interface (HMI) may include the touch screen 21 and the host computer interface, used to set setting parameters such as accelerating electrode voltage, suppressing electrode voltage, and filament current, and to display the beam current value, system status (standby, power-on self-test, initialization, and fault, etc.) in real time, as well as the set values ​​and actual output values ​​of the above setting parameters, so that operators can better understand the working status of the test power supply system of the electron beam equipment.

[0045] In addition, the main control unit 11 can also realize fault reminder function. Specifically, the main control unit 11 can monitor the voltage, current, temperature and other parameters of each power module in real time. When overvoltage of accelerating electrode, overvoltage of suppressing electrode, overcurrent of filament or over-temperature occurs, the protection is immediately triggered to cut off the output of the corresponding power module. At the same time, a fault alarm signal is issued through the host computer 20 to remind the operator to check in time. The resistance of filament (especially tungsten filament) is very small when cold. Directly applying high voltage can easily lead to overcurrent damage. The existing power supply scheme lacks a complete overcurrent and overvoltage protection mechanism, which poses a risk of damaging expensive filament components. This embodiment can detect overvoltage and overcurrent conditions in time, improving the reliability of the test power supply system of electron beam equipment. Correspondingly, the touch screen 21 and the host computer interface synchronously display the real-time values ​​of accelerating electrode voltage, suppressing electrode voltage, filament current and emission beam current, and show the parameter change trend in the form of curve graphs, so that the operator can intuitively grasp the test status; and the host computer 20 can automatically store test data and generate reports in Excel format for easy analysis of electron source performance stability by users.

[0046] Continue to refer to Figure 1 The test power system of the electron beam equipment can complete automated testing: the hardware supports the measurement of 3 independent filament power supplies, and can simultaneously connect 3 groups of filaments for parallel testing, improving the testing efficiency by more than 3 times; the host computer interface can also support batch parameter preset, and the main control unit automatically tests according to the preset order, synchronously recording the beam current-current characteristic curve of each group of filaments, reducing the operation steps of manual rotation testing and reducing human error.

[0047] In summary, the electron beam equipment's test power supply system integrates three power supplies into one unit, uniformly coordinated and controlled by a host computer. This enables precise parameter matching and automated operation of complex sequences, achieving integrated and collaborative control. Furthermore, the host computer simultaneously controls each power module, avoiding the lack of collaborative control and communication in traditional separate general-purpose power supplies, thus achieving precise parameter matching and rapid linkage adjustment. Secondly, each power module employs a high-stability reference voltage chip and closed-loop feedback control, resulting in minimal ripple and high stability, ensuring the accuracy and repeatability of measurement data and meeting the high-precision and high-stability power supply requirements. It also features built-in overcurrent and overvoltage protection functions, greatly reducing the risk of filament or power supply damage due to operational errors or circuit faults, achieving high safety and reliability. Finally, users can easily set up test procedures through the human-machine interface, with the system automatically executing and recording data in real time, significantly improving the efficiency and consistency of filament testing, reducing human error, and achieving intelligent and automated operation.

[0048] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A test power supply system for an electron beam device, characterized by, The application relates to a power supply module for an electron gun, which comprises the following parts: at least one power supply module; the power supply module comprises at least a master control unit, a slave control unit, an accelerating electrode power supply circuit, a suppressor electrode power supply circuit, a filament power supply circuit and a beam current sampling circuit; the master control unit is electrically connected with the accelerating electrode power supply circuit and is used for controlling the accelerating electrode power supply circuit to output a first adjustable voltage to an accelerating electrode of an electron gun; the master control unit is also used for outputting a set parameter execution instruction to the slave control unit; the set parameter execution instruction comprises at least a first set parameter execution instruction and a second set parameter execution instruction; the ripple coefficient of the first adjustable voltage is less than or equal to 0.01%; the slave control unit is used for controlling the suppressor electrode power supply circuit to output a second adjustable voltage to a suppressor electrode of the electron gun according to the first set parameter execution instruction; the slave control unit is also used for controlling the filament power supply circuit to output a first adjustable current to a filament of the electron gun according to the second set parameter execution instruction; the response period of the master control unit and the slave control unit is less than or equal to 50 ms; the stability of the first adjustable current is less than or equal to 0.05%; the beam current sampling circuit is electrically connected with the accelerating electrode power supply circuit and the accelerating electrode respectively and is used for acquiring an electron beam current and sending the electron beam current to the master control unit.

2. The test power supply system for an electron beam apparatus according to claim 1, characterized by The application further comprises: a host computer; the host computer is electrically connected with the master control unit and is used for sending a set parameter instruction to the master control unit; the master control unit is used for controlling the accelerating electrode power supply circuit and the slave control unit according to the set parameter instruction; the host computer is also used for receiving the electron beam current sent by the master control unit and adjusting the electron beam current through the master control unit when the difference between the electron beam current and a set beam current threshold value exceeds a first difference value.

3. The test power supply system for an electron beam apparatus according to claim 2, wherein the first difference value ranges from -5% to +5%; d is the set beam current threshold value.

4. The test power supply system for an electron beam apparatus according to claim 2, wherein the slave control unit is also used for collecting the second adjustable voltage and the first adjustable current and sending the second adjustable voltage and the first adjustable current to the master control unit; the master control unit is also used for collecting the first adjustable voltage; the host computer is also used for adjusting the second adjustable voltage, the first adjustable voltage and the first adjustable current according to corresponding set values.

5. The test power supply system for an electron beam apparatus according to claim 1, wherein the beam current sampling circuit comprises a first resistor and a first operational amplifier; the output end of the accelerating electrode power supply circuit is electrically connected with the first input end of the first operational amplifier; the second input end of the first operational amplifier is electrically connected with the accelerating electrode; the output end of the first operational amplifier is electrically connected with the master control unit and is used for converting the electron beam current into a beam current voltage and transmitting the beam current voltage to the master control unit; the first end of the first resistor is electrically connected with the output end of the first operational amplifier; the second end of the first resistor is electrically connected with the first input end of the first operational amplifier.

6. The test power supply system for electron beam apparatus according to claim 1, wherein the application further comprises a high-voltage isolation control unit; the high-voltage isolation control unit is electrically connected with the master control unit and the slave control unit respectively and is used for realizing communication isolation between the master control unit and the slave control unit.

7. The test power supply system for electron beam apparatuses according to claim 1, characterized in that, The application further comprises: a power supply unit and a high-voltage isolation power supply unit; The power supply unit is used for converting alternating city power into direct current and supplying power for the master control unit and the accelerating electrode power supply circuit; The high-voltage isolation power supply unit is electrically connected with the power supply unit and the slave control unit respectively, and is used for realizing power supply isolation between the master control unit and the slave control unit; The high-voltage isolation power supply unit is also used for supplying power for the suppressor electrode power supply circuit and the filament power supply circuit; The output end of the accelerating electrode power supply circuit is electrically connected with the output end of the high-voltage isolation power supply unit.

8. The test power supply system for an electron beam apparatus according to claim 7, wherein The accelerating electrode power supply circuit comprises a first transformer, a first voltage doubling rectifier circuit, a first filter and a second operational amplifier; The first transformer is electrically connected with the output end of the power supply unit, and is used for generating a first alternating voltage; the first voltage doubling rectifier circuit is electrically connected with the first transformer, and is used for converting the first alternating voltage into a first direct current voltage; the first filter is electrically connected with the first voltage doubling rectifier circuit, and is used for filtering the first direct current voltage to form the first adjustable voltage and outputting the first adjustable voltage through the output end of the first filter; the output end of the first filter is connected to ground through a first voltage regulating resistor and a second voltage regulating resistor in sequence; a first node is formed between the first voltage regulating resistor and the second voltage regulating resistor; The first input end of the second operational amplifier is connected to a first set voltage of the master control unit; the second input end of the second operational amplifier is connected to the first node; and the output end of the second operational amplifier is electrically connected with the control end of the first transformer.

9. The test power supply system for an electron beam apparatus according to claim 7, wherein The filament power supply circuit comprises a second transformer, a second rectifier circuit, a second filter, a current differential sampling unit and a third operational amplifier; The second transformer is electrically connected with the output end of the high-voltage isolation power supply unit, and is used for generating a first alternating current; the second rectifier circuit is electrically connected with the second transformer, and is used for converting the first alternating current into a first direct current; the second filter is electrically connected with the second rectifier circuit, and is used for filtering the first direct current to form a first adjustable current; A low-temperature drift resistor network is arranged between the second rectifier circuit and the second filter; the low-temperature drift resistor network is connected with the current differential sampling unit at both ends; the current differential sampling unit is used for converting the first direct current into a sampling voltage and transmitting the sampling voltage to the second input end of the third operational amplifier; the first input end of the third operational amplifier is connected to a second set voltage of the slave control unit; and the output end of the third operational amplifier is electrically connected with the control end of the second transformer.

10. The test power supply system for an electron beam apparatus according to claim 1, wherein Further comprising: A man-machine interaction unit; the man-machine interaction unit comprises a touch screen and an upper computer interface; The touch screen is used for receiving a set parameter input by a user; The upper computer interface is used for displaying the electron beam current, the first adjustable voltage, the second adjustable voltage and the first adjustable current.

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