A voltage control circuit and an electrostatic chuck voltage control system

Abstract

This application provides a voltage control circuit and an electrostatic chuck voltage control system. The voltage control circuit includes a voltage conversion circuit, a sampling circuit, and a protection circuit. The sampling circuit includes a voltage divider module, a current sampling module, a sampling amplification module, and an absolute value output module. The first terminal of the voltage divider module is connected to the output terminal of the voltage conversion circuit, the second terminal of the voltage divider module is connected to a reference ground, and the third terminal of the voltage divider module is connected to the first input terminal of the sampling amplification module. The current sampling module is connected in series in the loop containing the output terminal of the voltage conversion circuit, and its output terminal is connected to the second input terminal of the sampling amplification module. The sampling amplification module is connected to the absolute value output module. The first output terminal of the absolute value output module is used to output the absolute value of the voltage feedback signal, and the second output terminal is used to output the absolute value of the current feedback signal. The voltage control circuit provided by this application can reduce the probability of voltage overshoot in the high-voltage module output.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a voltage control circuit and an electrostatic chuck voltage control system. Background Technology

[0002] An electrostatic chuck (ESC) is a core workpiece clamping device in semiconductor manufacturing equipment, primarily used in several key stages of front-end wafer fabrication. Its core function is to securely, flatly, and without contamination, hold silicon wafers in a designated position within the process chamber using electrostatic force, without the use of mechanical clamps, to meet the requirements of nanometer-level precision manufacturing.

[0003] The power supply for a bipolar electrostatic chuck has a high-voltage module with a rated output voltage of several kilovolts. During operation, a voltage sampling signal is input to the high-voltage module, which then outputs a stable voltage based on the received signal. In related technologies, relays are typically used for line switching to achieve signal sampling in the sampling circuit. However, since the high-voltage module of the bipolar electrostatic chuck outputs both positive and negative voltages, while the downstream analog-to-digital converter (ADC) or control circuit can only process unipolar signals, a relay combined with an operational amplifier circuit is often used to flip the negative voltage to a positive voltage. However, because the relay's operating time may vary each time, this can easily lead to distortion or loss of the feedback signal, which can cause overshoot in the high-voltage module's output voltage, resulting in an electric field strength between the positive and negative electrodes exceeding the expected value. Summary of the Invention

[0004] In view of this, this application provides a voltage control circuit and an electrostatic chuck voltage control system, which can improve the consistency of voltage sampling signal feedback time and reduce the probability of high voltage module output voltage overshoot.

[0005] The first aspect of this application provides a voltage control circuit, including a voltage conversion circuit, a sampling circuit, and a protection circuit. The input terminal of the voltage conversion circuit is used to connect to a DC power supply, and the output terminal of the voltage conversion circuit is used to output DC power. The sampling circuit is connected to the output terminal of the voltage conversion circuit, the voltage feedback terminal of the sampling circuit is connected to the first input terminal of the protection circuit, the current feedback terminal of the sampling circuit is connected to the second input terminal of the protection circuit, the voltage feedback terminal of the sampling circuit is also connected to the comparison voltage input terminal of the voltage conversion circuit, and the control signal output terminal of the protection circuit is also connected to the disabling control terminal of the voltage conversion circuit. The sampling circuit includes a voltage divider module, a current sampling module, a sampling amplification module, and an absolute value output module. The first terminal of the voltage divider module is connected to the output terminal of the voltage conversion circuit, the second terminal of the voltage divider module is connected to the reference ground, and the third terminal of the voltage divider module is connected to the first input terminal of the sampling amplification module. The current sampling module is connected in series in the loop containing the output terminal of the voltage conversion circuit, and the output terminal of the current sampling module is connected to the second input terminal of the sampling amplification module. The sampling amplification module is also connected to the absolute value output module. The first output terminal of the absolute value output module serves as a voltage feedback terminal and is connected to the first input terminal of the protection circuit and the comparison voltage input terminal of the voltage conversion circuit. The second output terminal of the absolute value output module serves as a current feedback terminal and is connected to the second input terminal of the protection circuit. The absolute value output module uses an absolute value chip to process the received signal, and the first output terminal of the absolute value output module is used to output the absolute value of the voltage feedback signal, and the second output terminal of the absolute value output module is used to output the absolute value of the current feedback signal.

[0006] A second aspect of this application provides an electrostatic chuck voltage control system for use with an electrostatic chuck. The electrostatic chuck voltage control system includes a DC power supply and a voltage control circuit as described above. The DC power supply outputs DC power; the voltage control circuit is electrically connected to the electrostatic chuck and the DC power supply, and is used to convert the DC power output by the DC power supply and control the operation of the electrostatic chuck.

[0007] Compared to related technologies that use relays and inverters for signal sampling, the voltage control circuit provided in this application sets an absolute value output module in the sampling circuit and directly uses an absolute value chip to output the absolute value of the sampled signal. This avoids the delay caused by relay state switching, improves the consistency of voltage sampling signal feedback time, and reduces the probability of voltage sampling signal loss and distortion. This allows the voltage conversion circuit to receive the feedback signal in an orderly manner, thereby effectively reducing the probability of actual output voltage overshoot. Attached Figure Description

[0008] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be considered as a limitation on the scope of protection of this application. In the various drawings, similar components are numbered similarly.

[0009] Figure 1 A circuit block diagram of a voltage control circuit provided in an embodiment of this application.

[0010] Figure 2 A circuit block diagram of a sampling circuit provided in one embodiment of this application.

[0011] Figure 3 A partial circuit diagram of a sampling circuit provided in one embodiment of this application.

[0012] Figure 4 A partial circuit diagram of a protection circuit provided in one embodiment of this application.

[0013] Figure 5 This is a partial circuit diagram of a voltage conversion circuit provided in one embodiment of this application.

[0014] Figure 6 This is a structural block diagram of an electrostatic chuck voltage control system provided in an embodiment of this application. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0016] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or may also have an intervening component. When a component is considered to be "placed" on another component, it can be directly placed on the other component or may also have an intervening component.

[0017] It should also be noted that the methods disclosed in the embodiments of this application or the methods shown in the flowcharts include one or more steps for implementing the method. Without departing from the scope of the claims, the execution order of multiple steps can be interchanged, and some steps can also be deleted.

[0018] 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 with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0020] Some embodiments will now be described with reference to the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0021] Electrostatic chucks (ESCs) are core workpiece clamping devices in semiconductor manufacturing equipment, primarily used in several key stages of front-end wafer fabrication. Their core function is to securely, flatly, and without contamination, hold silicon wafers in a designated position within the process chamber using electrostatic force, without the use of mechanical clamps, to meet the requirements of nanometer-level precision manufacturing.

[0022] The power supply for a bipolar electrostatic chuck has a high-voltage module with a rated output voltage of several kilovolts. During operation, a voltage sampling signal is input to the high-voltage module, which then outputs a stable voltage based on the received signal. In related technologies, relays are typically used for line switching to achieve signal sampling in the sampling circuit. However, since the high-voltage module of the bipolar electrostatic chuck outputs both positive and negative voltages, while the downstream analog-to-digital converter (ADC) or control circuit can only process unipolar signals, a relay combined with an operational amplifier circuit is often used to flip the negative voltage to a positive voltage. However, because the relay's operating time may vary each time, this can easily lead to distortion or loss of the feedback signal, potentially causing overshoot in the high-voltage module's output voltage, resulting in an electric field strength between the positive and negative electrodes exceeding the expected value.

[0023] Based on this, this application provides a voltage control circuit and an electrostatic chuck voltage control system to reduce the probability of output voltage overshoot.

[0024] Please see Figure 1 , Figure 1 This is a circuit block diagram of a voltage control circuit 10 provided in one embodiment of this application. It is understood that the voltage control circuit 10 can be disposed in a bipolar electrostatic chuck or any other electronic device used to output a bipolar DC voltage. This application describes the application of the voltage control circuit 10 in a bipolar electrostatic chuck as an example; this application does not limit the specific application environment of the voltage control circuit 10.

[0025] The voltage control circuit 10 includes a voltage conversion circuit 11, a sampling circuit 12, and a protection circuit 13. The input terminal IN_DC of the voltage conversion circuit 11 is connected to the DC power supply 20, and the output terminal OUT_DC of the voltage conversion circuit 11 is used to output DC power to the electrostatic chuck. The sampling circuit 12 is connected to the output terminal OUT_DC of the voltage conversion circuit 11. The voltage feedback terminal Fb_u of the sampling circuit 12 is also connected to the first input terminal In1 of the protection circuit 13, and the current feedback terminal Fb_i of the sampling circuit 12 is connected to the second input terminal In2 of the protection circuit 13. The voltage feedback terminal Fb_u of the sampling circuit 12 is also connected to the comparison voltage input terminal Com_u of the voltage conversion circuit 11. The control signal output terminal Out_ctr of the protection circuit 13 is also connected to the disabling control terminal DIS of the voltage conversion circuit 11.

[0026] The voltage conversion circuit 11 is used to perform voltage conversion processing on the DC power received at the input terminal IN_DC, so as to output a positive or negative voltage with a preset voltage value through the output terminal OUT_DC as needed, thereby realizing the function corresponding to the electrostatic chuck where the voltage control circuit 10 is located, such as the electrostatic adsorption function.

[0027] The sampling circuit 12 is connected to the output terminal OUT_DC of the voltage conversion circuit 11 to perform real-time voltage sampling and real-time current sampling on the output terminal OUT_DC of the voltage conversion circuit 11, and to process the actual output voltage and actual output current sampled, so as to output the absolute value of the voltage feedback signal and the absolute value of the current feedback signal to the protection circuit 13 through the voltage feedback terminal Fb_u and the current feedback terminal Fb_i respectively.

[0028] Understandably, the absolute value of the voltage feedback signal is proportional to the actual output voltage of the output terminal OUT_DC of the voltage conversion circuit 11, and the absolute value of the current feedback signal is proportional to the actual output current of the output terminal OUT_DC of the voltage conversion circuit 11. Thus, after receiving the absolute values ​​of the voltage and current feedback signals, the protection circuit 13 can determine whether an abnormality has occurred and generate a corresponding shutdown control signal, which is then output to the disabling control terminal DIS of the voltage conversion circuit 11 via the control signal output terminal Out_ctr. The voltage conversion circuit 11 can then stop operating under the control of the shutdown control signal output by the protection circuit 13.

[0029] Meanwhile, the voltage conversion circuit 11 is also used to adjust the actual output voltage of the output terminal OUT_DC according to the voltage deviation between the absolute value of the voltage feedback signal received by the comparison voltage input terminal Com_u and the preset voltage value, so that the actual output voltage conforms to the preset voltage value.

[0030] Please continue reading. Figure 2 In some embodiments, the sampling circuit 12 includes a voltage divider module 121, a current sampling module 122, a sampling amplification module 123, and an absolute value output module 125. The first terminal of the voltage divider module 121 is connected to the output terminal OUT_DC of the voltage conversion circuit 11, and the second terminal of the voltage divider module 121 is connected to the reference ground GND. The third terminal of the voltage divider module 121 is connected to the first input terminal of the sampling amplification module 123. The current sampling module 122 is connected in series in the loop containing the output terminal OUT_DC of the voltage conversion circuit 11. Figure 2 (Not shown) The output of the current sampling module 122 is connected to the second input of the sampling amplification module 123. The sampling amplification module 123 is also connected to the absolute value output module 125. The first output of the absolute value output module 125 serves as a voltage feedback terminal Fb_u, connected to the first input terminal In1 of the protection circuit 13 and the comparison voltage input terminal Com_u of the voltage conversion circuit 11. The second output of the absolute value output module 125 serves as a current feedback terminal Fb_i, connected to the second input terminal In2 of the protection circuit 13. The first output of the absolute value output module 125 is used to output the absolute value of the voltage feedback signal, and the second output of the absolute value output module 125 is used to output the absolute value of the current feedback signal.

[0031] The voltage divider module 121 is used to reduce the high voltage of the output terminal OUT_DC to a low voltage signal according to a preset ratio. For example, it reduces the actual output voltage of OUT_DC, which is as high as several kilovolts, to a primary voltage sampling signal of about +10 volts or -10 volts, so as to facilitate subsequent signal processing and circuit control. In some embodiments, the voltage divider module 121 may include several voltage divider resistors connected in series and / or in parallel. This application does not limit the specific circuit of the voltage divider module 121.

[0032] The current sampling module 122 is used to sample the actual output current flowing through the output terminal OUT_DC and convert the sampled actual output current into a bipolar voltage signal that is proportional to the actual output current, for example, into a primary current sampling signal. That is, the primary current sampling signal is essentially a voltage signal, and the voltage amplitude of the primary current sampling signal is proportional to the current value of the actual output current. In some embodiments, the current sampling module 122 may include a sampling resistor connected in series in the loop containing the output terminal OUT_DC of the voltage conversion circuit 11. This application does not limit the specific circuit of the current sampling module 122.

[0033] The sampling amplification module 123 is used to amplify the primary voltage sampling signal output by the voltage divider module 121 and the primary current sampling signal output by the current sampling module 122, so as to amplify the primary voltage sampling signal and the primary current sampling signal to appropriate values ​​respectively, so as to obtain the corresponding voltage amplification signal and current amplification signal, thereby making the amplitude of the voltage amplification signal and the current amplification signal meet the requirements of subsequent signal processing, suppressing noise, and improving measurement accuracy.

[0034] Understandably, in related technologies, when using relays combined with operational amplifiers to sample bipolar signals, the sampling time may fluctuate due to inconsistent relay switching times. Furthermore, signal segments may be missed or the sampled signal may be distorted during relay switching. However, the absolute value output module 125 in this application uses an absolute value chip to process the signal and output a constant positive value. Thus, compared to the use of relays and operational amplifiers for signal sampling in related technologies, the voltage control circuit 10 provided in this application, by setting the absolute value output module 125 in the sampling circuit 12, directly uses the absolute value chip to output the absolute value of the sampled signal. This avoids the delay caused by relay state switching, improves the consistency of the voltage sampling signal feedback time, and reduces the probability of voltage sampling signal loss and distortion. This ensures that the voltage conversion circuit 11 receives the feedback signal in an orderly manner, thereby effectively reducing the probability of actual output voltage overshoot.

[0035] In some embodiments, the sampling circuit 12 further includes a calibration module 124, which is connected between the sampling amplification module 123 and the absolute value output module 125. The calibration module 124 is used to calibrate the voltage amplification signal and the current amplification signal output by the sampling amplification module 123, respectively, so as to output voltage feedback signal and current feedback signal to the absolute value output module 125, thereby enabling the absolute value output module 125 to perform signal processing on the voltage feedback signal and the current feedback signal, respectively, to output the absolute value of the voltage feedback signal and the absolute value of the current feedback signal.

[0036] Please continue reading. Figure 3 In some embodiments, the sampling amplification module 123 includes a voltage amplification unit 1231 and a current amplification unit 1232. The voltage amplification unit 1231 is connected to the output terminal FB of the voltage divider module 121 to obtain the primary voltage sampling signal, and outputs a voltage amplification signal according to the primary voltage sampling signal; the current amplification unit 1232 is connected to the output terminal HGND of the current sampling module 122 to obtain the primary current sampling signal, and outputs a current amplification signal according to the primary current sampling signal.

[0037] The voltage amplification unit 1231 includes resistors R1 to R3, capacitor C1, and operational amplifier OP1. One end of resistor R1 is grounded, and the other end is connected to one end of resistor R2. The other end of resistor R2 is connected to the output of operational amplifier OP1. The negative input of operational amplifier OP1 is connected between resistors R1 and R2, and the positive input of operational amplifier OP1 is grounded through capacitor C1. One end of resistor R3 is connected between the positive input of operational amplifier OP1 and capacitor C1, and the other end of resistor R3 is used to receive the primary voltage sampling signal. The output of operational amplifier OP1 is used to output the amplified voltage signal. Thus, resistors R1 to R3, capacitor C1, and operational amplifier OP1 together form an amplification circuit to amplify the primary voltage sampling signal FB and output the amplified voltage signal.

[0038] In this embodiment, the circuit structure of the current amplification unit 1232 is largely the same as that of the voltage amplification unit 1231, and will not be described again here. Specifically, one end of resistor R6 in the current amplification unit 1232 is used to receive the primary current sampling signal, and the output of operational amplifier OP2 is used to output the amplified current signal. In other embodiments, other current amplification circuits different from those in the voltage amplification unit 1231 may be used to process the primary current sampling signal, and this application does not impose any limitations on this.

[0039] In some embodiments, the calibration module 124 includes a voltage calibration unit 1241 and a current calibration unit 1242. The voltage calibration unit 1241 receives a voltage amplification signal for calibration and outputs a voltage feedback signal to the absolute value output module 125. The current calibration unit 1242 receives a current amplification signal for calibration and outputs a current feedback signal to the absolute value output module 125.

[0040] The voltage calibration unit 1241 includes resistors R7 to R10, a sliding resistor R11, and an operational amplifier OP3. One end of resistor R7 is connected to the output of operational amplifier OP1 to receive the voltage amplification signal. The other end of resistor R7 is connected to the first fixed end of sliding resistor R11, the second fixed end of sliding resistor R11 is connected to one end of resistor R8, and the other end of resistor R8 is grounded. The sliding end of sliding resistor R11 is connected to one end of resistor R9, and the other end of resistor R9 is connected to the positive input of operational amplifier OP3. One end of resistor R10 is connected to the output of operational amplifier OP3, and the other end of resistor R10 is connected to the negative input of operational amplifier OP3.

[0041] Understandably, in the voltage calibration unit 1241, resistors R7 to R8 and the sliding resistor R11 together form a calibration circuit. The calibration circuit finely changes the adjustment coefficient through the mechanical adjustment of the sliding resistor R11, thereby flexibly and accurately adjusting the voltage value received at the positive input terminal of operational amplifier OP3. Resistors R9 to R10 and operational amplifier OP3 together form a voltage follower, used to isolate the calibration circuit from the absolute value output module 125. Thus, after receiving and calibrating the voltage amplification signal, the calibration circuit outputs it to the voltage follower, which then outputs a voltage feedback signal, i.e., a voltage feedback signal is output through the output terminal of operational amplifier OP3.

[0042] In this embodiment, the circuit structure of the current calibration unit 1242 is largely the same as that of the voltage calibration unit 1241, and will not be described again here. Understandably, in other embodiments, other current calibration units different from the voltage calibration unit 1241 may be used to calibrate the current amplified signal.

[0043] In some embodiments, the absolute value output module 125 includes a first absolute value chip 1251 and a second absolute value chip 1252, with the output terminal of the first absolute value chip 1251 serving as the first output terminal Fb_u, and the output terminal of the second absolute value chip 1252 serving as the second output terminal Fb_i. Specifically, the first absolute value chip 1251 receives a voltage feedback signal and processes it to output the absolute value of the voltage feedback signal through the first output terminal Fb_u; the second absolute value chip 1252 receives a current feedback signal and processes it to output the absolute value of the current feedback signal through the second output terminal Fb_i.

[0044] In some embodiments, the output of operational amplifier OP3 also outputs a voltage feedback signal through resistor R17, and the output of operational amplifier OP4 also outputs a current feedback signal through resistor R18. Resistors R17 and R18 can be zero-ohm resistors. Understandably, the absolute value of the voltage feedback signal output from the first output terminal Fb_u and the absolute value of the current feedback signal output from the second output terminal Fb_i are both consistently positive monitored values. The voltage feedback signal output from resistor R17 is a voltage sample value that can be positive or negative, and the current feedback signal output from resistor R18 is a current sample value that can be positive or negative.

[0045] Thus, through Figure 3 The circuit diagram shown illustrates that the sampling circuit 12 provided in this application can effectively avoid time differences when the absolute value of the output voltage feedback signal is reached by using an absolute value chip, thereby improving the consistency of the feedback time when the absolute value of the voltage feedback signal is output to the comparison voltage input terminal Com_u, and reducing the probability of overshoot in the actual output voltage of the voltage conversion circuit 11.

[0046] Understandably, Figure 3 The circuit shown is a partial circuit diagram of the sampling circuit 12 in one embodiment of this application. In other embodiments, other sampling circuits 12 with absolute value chips may also be formed to improve the consistency of the feedback time of the voltage sampling signal. This application does not limit the specific circuit of the sampling circuit 12.

[0047] Please continue reading. Figure 4 In some embodiments, the protection circuit 13 includes an anomaly detection module 131, an enable switching module 132, and a signal merging module 133.

[0048] Among them, the first input terminal of the anomaly detection module 131 (i.e. Figure 4 The first input terminal In1) serves as the first input terminal of the protection circuit 13 to receive the absolute value of the voltage feedback signal, and the second input terminal of the abnormal detection module 131 (i.e. Figure 4 The second input terminal In2) serves as the second input terminal of the protection circuit 13 to receive the absolute value of the current feedback signal. The output terminal of the anomaly detection module 131 is connected to the first input terminal of the signal merging module 133. The anomaly detection module 131 is used to monitor the absolute values ​​of the voltage feedback signal and the current feedback signal in real time, and outputs an anomaly detection signal characterizing an abnormal state when at least one of the absolute values ​​of the voltage feedback signal and the current feedback signal exceeds a corresponding preset threshold. In some embodiments, the anomaly detection signal can be a high-level signal to indicate that an anomaly has occurred in the voltage control circuit 10, such as an overvoltage anomaly and / or an overcurrent anomaly. In other embodiments, the anomaly detection signal can also be a low-level signal, and this application does not limit this.

[0049] The input terminal of the enable switching module 132 is used to receive the enable status signal EN. The output terminal of the enable switching module 132 is connected to the second input terminal of the signal merging module 133. The enable switching module 132 is used to monitor the enable status signal EN, and when the enable status signal EN meets the first preset range, it outputs an enable failure signal EN_fai indicating that the enable has failed. For example, when the enable status signal EN is less than a preset voltage value, it indicates that the enable status signal EN has failed, and the voltage conversion circuit 11 needs to be stopped. At this time, the output terminal of the enable switching module 132 outputs a high-level enable failure signal EN_fai to the second input terminal of the signal merging module 133.

[0050] The output terminal of the signal merging module 133 serves as the control signal output terminal Out_ctr of the protection circuit 13. The signal merging module 133 outputs a shutdown control signal Off to the disabling control terminal DIS when at least one of the abnormal detection signal Ano and the enable failure signal EN_fai is detected. In this way, the signal merging module 133 can control the voltage conversion circuit 11 to stop working when the voltage control circuit 10 malfunctions or switches from an enabled state to a disabled state, thus achieving the safety protection function of the voltage control circuit 10.

[0051] Please refer to it again. Figure 4 In some embodiments, the anomaly detection module 131 includes an anomaly detection unit 1311, a signal broadening unit 1312, and a comparison unit 1313. The first input terminal of the anomaly detection unit 1311 (i.e....) Figure 4 The first input terminal In1 of the fault detection unit 1311 is used to receive the absolute value of the voltage feedback signal, and the second input terminal of the fault detection unit 1311 (i.e., ...) is used to receive the absolute value of the voltage feedback signal. Figure 4 The second input terminal In2 is used to receive the absolute value of the current feedback signal. The input terminal of the signal broadening unit 1312 is connected to the output terminal of the abnormal detection unit 1311. The output terminal of the signal broadening unit 1312 is connected to the input terminal of the comparison unit 1313. The output terminal of the comparison unit 1313 is used to output the abnormal detection signal Ano.

[0052] The anomaly detection unit 1311 outputs a short-term anomaly signal Over when at least one of the absolute values ​​of the voltage feedback signal and the current feedback signal exceeds a corresponding preset threshold. The signal broadening unit 1312 broadens the short-term anomaly signal to generate a long-term anomaly signal Alarm. The comparison unit 1313 outputs an anomaly detection signal Ano when it detects that the long-term anomaly signal Alarm meets a second preset range at its own input. In this embodiment, the short-term anomaly signal Over can be a high-level signal. In other embodiments, the short-term anomaly signal Over can also be a low-level signal, and this application does not limit this.

[0053] Understandably, if the short-term abnormal signal Over output by the abnormality detection unit 1311 is too brief, it is not conducive to the subsequent control circuit's accurate capture and processing. Therefore, in this embodiment, the signal broadening unit 1312 converts the short-term abnormal signal Over output by the abnormality detection unit 1311 into a longer-lasting abnormal signal Alarm, and the comparison unit 1313 triggers the output of the abnormality detection signal Ano when the value of the long-lasting abnormal signal Alarm reaches a second preset range, thereby ensuring the control effect of the abnormality detection signal Ano.

[0054] In some embodiments, the anomaly detection unit 1311 includes an overvoltage detection subunit 1311a, an overcurrent detection subunit 1311b, and a merging subunit 1311c. The first input terminal of the overvoltage detection subunit 1311a serves as the first input terminal of the protection circuit 13. The second input terminal of the overvoltage detection subunit 1311a is used to receive a first reference voltage ref1. The output terminal of the overvoltage detection subunit 1311a is connected to the first input terminal of the merging subunit 1311c. The overvoltage detection subunit 1311a outputs an overvoltage detection signal O_vol when the absolute value of the voltage feedback signal is greater than the first reference voltage ref1. For example, the overvoltage detection signal O_vol can be a high-level signal.

[0055] The first input terminal of the overcurrent detection subunit 1311b serves as the second input terminal of the protection circuit 13. The second input terminal of the overcurrent detection subunit 1311b is used to receive the second reference voltage ref2. The output terminal of the overcurrent detection subunit 1311b is connected to the second input terminal of the merging subunit 1311c. The overcurrent detection subunit 1311b outputs an overcurrent detection signal I_vol when the absolute value of the current feedback signal is greater than the first reference voltage ref1. For example, the overcurrent detection signal I_vol can be a high-level signal.

[0056] The output of the merging subunit 1311c serves as the output of the anomaly detection module 131. The merging subunit 1311c outputs a corresponding anomaly detection signal Over when at least one of the overvoltage detection signal O_vol and the overcurrent detection signal I_vol is detected. The first reference voltage ref1 and the second reference voltage ref2 are generated by corresponding reference circuits, and these reference circuits are located on the same circuit board as the voltage control circuit 10. This improves the stability of the first reference voltage ref1 and the second reference voltage ref2, thereby improving the stability of the short-term anomaly signal Over and the shutdown control signal Off, reducing the probability of falsely triggering the shutdown control signal Off, and preventing the voltage conversion circuit 11 from being cut off by the falsely triggered shutdown control signal Off during normal operation, which could lead to a sudden change in the electric field and affect the sheath edge.

[0057] Understandably, the overvoltage detection subunit 1311a and overcurrent detection subunit 1311b in the embodiments of this application may each include a comparison circuit, for example... Figure 4 The circuits shown herein do not impose any restrictions on the specific circuit structures of the overvoltage detection subunit 1311a and the overcurrent detection subunit 1311b. The circuit structure of the merging subunit 1311c is largely the same as that of the signal merging module 133; please refer to the relevant content below for details, which will not be repeated here.

[0058] Please refer to it again. Figure 4In some embodiments, the signal broadening unit 1312 may include resistors R37-R40, capacitors C5-C6, a D flip-flop 13121, and a switching transistor T1. The first end of resistor R37 serves as the input of the signal broadening unit 1312, connected to the output of the abnormality detection unit 1311 to receive a short-term abnormal signal Over. The second end of resistor R37 is connected to the input D1 of the D flip-flop 13121. The first end of capacitor C5 is connected between the second end of resistor R37 and the input D1, and the second end of capacitor C5 is grounded. The output Q1 of the D flip-flop 13121 is connected to the first end of resistor R39. The second end of resistor R39 is connected to the clock signal input pin CLK of the D flip-flop 13121. The drain of the switching transistor T1 is connected between the second end of resistor R39 and the clock signal input pin CLK. The source of the switching transistor T1 is grounded. The gate of the switching transistor T1 is connected to the first end of resistor R38, and the second end of resistor R38 is used to receive a reset signal Reset. The first terminal of capacitor C6 is connected between the gate of switching transistor T1 and the first terminal of resistor R38, and the second terminal of capacitor C6 is connected to the pull-up power supply. The first terminal of resistor R40 is connected between the first terminal of resistor R39 and the output terminal Q1, and the second terminal of resistor R40 serves as the output terminal of signal broadening unit 1312.

[0059] Understandably, when the input of signal widening unit 1312 does not receive a short-term abnormal signal Over (i.e., the voltage at the first end of resistor R37 is low), output Q1 outputs a low-level signal, and the clock signal input pin CLK has no signal. When the high-level reset signal Reset is not triggered, the gate voltage of switch T1 is low, and switch T1 is not turned on. When the input of signal widening unit 1312 receives a high-level short-term abnormal signal Over, because the POL pin of D flip-flop 13121 is grounded, output Q1 outputs a high-level signal. This high-level signal is then input to the clock signal input pin CLK of D flip-flop 13121 after passing through resistor R39. The clock signal input pin CLK captures the rising edge signal, triggering the latch state of D flip-flop 13121, i.e., output Q1 continuously outputs a high-level signal, which is then output as a long-term abnormal signal Alarm after passing through resistor R40.

[0060] When no short-term abnormal signal Over is received (i.e., the voltage at the first terminal of resistor R37 is low), a reset is required. This is achieved by manually providing a Reset signal externally. When the Reset signal is high, the gate voltage of switch T1 is high, and switch T1 is turned on. The clock signal input pin CLK is pulled low. At this time, both the clock signal input pin CLK and the POL pin are low, and the D flip-flop 13121 returns to its follower state, transmitting the current signal from input D1 to output Q1. Therefore, input D1 is low, and output Q1 is also low, preventing the signal broadening unit 1312 from outputting a long-term abnormal signal Alarm.

[0061] Understandably, the comparator unit 1313 may include a comparator circuit composed of operational amplifiers, as detailed in the following document. Figure 4 This will not be elaborated further here. Moreover, the reference voltage received by the comparison unit 1313 is also an onboard input, which helps to improve the stability of the long-term abnormal signal Alarm, thereby improving the stability of the voltage control circuit 10.

[0062] Please refer to it again. Figure 4 In some embodiments, the signal merging module 133 includes a first diode D4, a second diode D3, and a first resistor R27. The anode of the first diode D4 serves as the first input terminal of the signal merging module 133 and is connected to the output terminal of the anomaly detection module 131 to receive the anomaly detection signal Ano. The cathode of the first diode D4 is connected to the first terminal of the first resistor R27. The anode of the second diode D3 serves as the second input terminal of the signal merging module 133 and is connected to the output terminal of the enable switching module 132 to receive the enable failure signal EN_fai. The cathode of the second diode D3 is connected between the cathode of the first diode D4 and the first terminal of the first resistor R27. The second terminal of the first resistor R27 is grounded, and the first terminal of the first resistor R27 also serves as the output terminal of the signal merging module 133 for outputting the shutdown control signal Off.

[0063] Based on the design of the signal merging module 133, when at least one of the high-level abnormal detection signal Ano and the shutdown control signal Off is input to the signal merging module 133, the signal merging module 133 can output a high-level shutdown control signal Off.

[0064] In some embodiments, the protection circuit 13 further includes a status display module 134. The status display module 134 is used to output various status signals to drive corresponding indicator lights to flash. For example, the status display module 134 can output a high-level alarm drive signal Alarm_status when it receives an abnormal detection signal Ano to illuminate the corresponding alarm light. The status display module 134 can also output a low-level shutdown control signal Off_status when the shutdown control signal Off is high to control the corresponding relay to turn off. The status display module 134 can also receive the absolute value of the voltage feedback signal through the input terminal V_in, and when the absolute value of the voltage feedback signal reaches a preset voltage threshold, output a high-level working indicator signal Work_status to illuminate the corresponding working indicator light. In other embodiments, the protection circuit 13 can also be equipped with more circuits to achieve more indication functions, which will not be described in detail here.

[0065] In this embodiment, the voltage source connected to the first terminal of resistor R19, and the voltage sources generating the second, third, and fourth reference voltages, can be voltage sources on the circuit board of the electronic device where the voltage control circuit 10 is located, making the first, second, third, and fourth reference voltages onboard input voltages. Thus, compared to externally input reference voltages, the onboard input first, second, third, and fourth reference voltages have higher stability, which helps improve the stability of the control signal output by the protection circuit 13, reduces the probability of the voltage conversion circuit 11 interrupting its output voltage due to unstable control signals output by the protection circuit 13, and reduces the impact on the sheath edge. In some embodiments, the voltage of the voltage source can be 12.97V, and this application does not limit the specific voltage of the voltage source. The voltage sources used to generate the first, second, third, and fourth reference voltages can be equal or unequal, and this application does not limit this.

[0066] Please continue reading. Figure 5 In some embodiments, the voltage conversion circuit 11 includes a disability control module 111, an error amplification module 112, and a control chip 113.

[0067] Among them, the first input terminal of the error amplification module 112 (i.e. Figure 5 The first input terminal Com_u in the comparison voltage module is used as the comparison voltage input terminal Com_u, and the second input terminal of the error amplifier module 112 (i.e. Figure 5 The second input terminal (In_ref) is used to receive the reference voltage signal, and the output terminal of the error amplifier module 112 is connected to the voltage control pin Vset of the control chip 113. The input terminal of the disabling control module 111 (i.e. Figure 5The input terminal DIS in the control chip 111 is used as the disabling control terminal DIS. The output terminal of the disabling control module 111 is connected to the circuit where the second input terminal of the error amplification module 112 is located, the circuit where the output terminal of the error amplification module 112 is located, and the disabling pin SD of the control chip 113.

[0068] The error amplification module 112 is used to output a voltage control signal to the control chip 113 based on the absolute value of the voltage feedback signal. The control chip 113 is used to adjust the actual output voltage of the output terminal OUT_DC of the voltage conversion circuit 11 based on the voltage control signal. The disabling control module 111 is used to control the error amplification module 112 and the control chip 113 to stop working.

[0069] Thus, in the voltage conversion circuit 11 provided in this application embodiment, the disabling control module 111, in response to the shutdown control signal, can simultaneously pull down the signals of the circuit containing the second input terminal of the error amplification module 112, the circuit containing the output terminal of the error amplification module 112, and the disabling pin SD of the control chip 113, causing the error amplification module 112 and the control chip 113 to stop working. In this way, compared to simply pulling down one signal pin, the disabling control module 111 provided in this application can effectively reduce signal residue, especially during rapid enable-off and enable-on operations, further reducing the probability of output voltage overshoot and improving the stability of the actual output voltage of the output terminal OUT_DC of the voltage conversion circuit 11.

[0070] In some embodiments, the output terminals of the disability control module 111 include a first output terminal Out_1, a second output terminal Out_2, and a third output terminal Out_3. The disability control module 111 includes a first disability control unit 1111, a second disability control unit 1112, and a third disability control unit 1113.

[0071] The first terminals of the first disability control unit 1111, the second disability control unit 1112, and the third disability control unit 1113 are all grounded. The second terminal of the first disability control unit 1111 serves as the first output terminal Out_1 of the disability control module 111 and is connected to the circuit containing the second input terminal of the error amplification module 112. The second terminal of the second disability control unit 1112 serves as the second output terminal Out_2 of the disability control module 111 and is connected to the circuit containing the output terminal of the error amplification module 112. The second terminal of the third disability control unit 1113 serves as the third output terminal Out_3 of the disability control module 111 and is connected to the disability pin SD. The control terminals of the first disability control unit 1111, the second disability control unit 1112, and the third disability control unit 1113 together serve as the disability control terminal DIS of the voltage conversion circuit 11.

[0072] Taking the first disability control unit 1111 as an example, the first disability control unit 1111 may include a switch transistor T2 and a resistor R41. The first terminal of the switch transistor T1 is grounded as the first terminal of the first disability control unit 1111, the second terminal of the switch transistor T1 is the first output terminal Out_1 of the first disability control unit 1111, the third terminal of the switch transistor T1 is connected to the first terminal of the resistor R41, and the other terminal of the resistor R41 is the control terminal of the first disability control unit 1111. When the disability control terminal DIS receives the shutdown control signal Off, the switch transistor T2 is grounded, pulling down the signal at the first output terminal Out_1, thereby pulling down the signal in the circuit containing the second input terminal of the error amplification module 112.

[0073] The circuit structures of the second disability control unit 1112 and the third disability control unit 1113 are roughly the same as those of the first disability control unit 1111, and will not be described in detail here.

[0074] Understandably, the error amplification module 112 may include electronic devices such as operational amplifiers, for example, see [link to relevant documentation]. Figure 5 The circuit diagram of the error amplifier module 112 is shown. This application does not limit the specific circuit structure of the error amplifier module 112.

[0075] Understandably, the control chip 113 includes a high-voltage module ( Figure 5 (Not shown), used to control the output voltage of the voltage conversion circuit 11, OUT_DC. This application does not limit the specific model of the control chip 113.

[0076] Please continue reading. Figure 6 This application also provides an electrostatic chuck voltage control system 100, applied to an electrostatic chuck 200. The electrostatic chuck voltage control system 100 includes a voltage control circuit 10 and a DC power supply 20. The DC power supply 20 outputs DC power. The voltage control circuit 10 is electrically connected to the electrostatic chuck 200 and the DC power supply 20. The voltage control circuit 10 converts the DC power output from the DC power supply 20 to supply power to the electrostatic chuck 200 and controls the operation of the electrostatic chuck 200. Understandably, the electrostatic chuck voltage control system 100 can be applied, for example, to an electrostatic chuck 200 in a semiconductor manufacturing apparatus, or to an electrostatic chuck on other manufacturing equipment. This application does not limit the specific application scenarios of the electrostatic chuck voltage control system 100.

[0077] It is understood that the above figures are merely illustrative of the processes included in the method according to exemplary embodiments of the present invention, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Furthermore, it is readily understood that these processes may, for example, be executed synchronously or asynchronously in multiple modules.

[0078] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A voltage control circuit, characterized in that, The device includes a voltage conversion circuit, a sampling circuit, and a protection circuit. The input terminal of the voltage conversion circuit is used to connect to a DC power supply, and the output terminal of the voltage conversion circuit is used to output DC power. The sampling circuit is connected to the output terminal of the voltage conversion circuit. The voltage feedback terminal of the sampling circuit is connected to the first input terminal of the protection circuit, and the current feedback terminal of the sampling circuit is connected to the second input terminal of the protection circuit. The voltage feedback terminal of the sampling circuit is also connected to the comparison voltage input terminal of the voltage conversion circuit, and the control signal output terminal of the protection circuit is also connected to the disabling control terminal of the voltage conversion circuit. The sampling circuit includes a voltage divider module, a current sampling module, a sampling amplification module, and an absolute value output module. The first terminal of the voltage divider module is connected to the output terminal of the voltage conversion circuit, the second terminal of the voltage divider module is connected to a reference ground, and the third terminal of the voltage divider module is connected to the first input terminal of the sampling amplification module. The current sampling module is connected in series in the loop containing the output terminal of the voltage conversion circuit, and its output terminal is connected to the second input terminal of the sampling amplification module. The sampling amplification module is also connected to the absolute value output module. The first output terminal of the absolute value output module serves as the voltage feedback terminal, connected to the first input terminal of the protection circuit and the comparison voltage input terminal of the voltage conversion circuit. The second output terminal of the absolute value output module serves as the current feedback terminal, connected to the second input terminal of the protection circuit. The absolute value output module processes the received signal using an absolute value chip, and its first output terminal outputs the absolute value of the voltage feedback signal, while its second output terminal outputs the absolute value of the current feedback signal. The voltage conversion circuit includes a disabling control module, an error amplification module, and a control chip; Wherein, the first input terminal of the error amplification module serves as the comparison voltage input terminal, the second input terminal of the error amplification module is used to receive the reference voltage signal, the output terminal of the error amplification module is connected to the voltage control pin of the control chip, the input terminal of the disabling control module serves as the disabling control terminal, and the output terminal of the disabling control module is connected to the circuit containing the second input terminal of the error amplification module, the circuit containing the output terminal of the error amplification module, and the disabling pin of the control chip. The error amplification module is used to output a voltage control signal to the control chip based on the absolute value of the voltage feedback signal. The control chip is used to adjust the actual output voltage of the output terminal of the voltage conversion circuit based on the voltage control signal. The disabling control module is used to control the error amplification module and the control chip to stop working.

2. The voltage control circuit as described in claim 1, characterized in that, The sampling amplification module includes a voltage amplification unit and a current amplification unit. The voltage amplification unit is connected to the voltage divider module to obtain a primary voltage sampling signal and outputs a voltage amplification signal based on the primary voltage sampling signal. The current amplification unit is connected to the current sampling module to obtain a primary current sampling signal and outputs a current amplification signal based on the primary current sampling signal. The sampling circuit further includes a calibration module, which is connected between the sampling amplification module and the absolute value output module. The calibration module includes a voltage calibration unit and a current calibration unit. The voltage calibration unit receives the voltage amplification signal and performs calibration to output the voltage feedback signal to the absolute value output module. The current calibration unit receives the current amplification signal and performs calibration to output the current feedback signal to the absolute value output module.

3. The voltage control circuit as described in claim 2, characterized in that, The absolute value output module includes a first absolute value chip and a second absolute value chip. The first absolute value chip receives the voltage feedback signal and processes it to output the absolute value of the voltage feedback signal through the first output terminal. The second absolute value chip receives the current feedback signal and processes it to output the absolute value of the current feedback signal through the second output terminal.

4. The voltage control circuit as described in claim 1, characterized in that, The protection circuit includes an anomaly detection module, an enable switching module, and a signal merging module. Wherein, the first input terminal of the anomaly detection module serves as the first input terminal of the protection circuit to receive the absolute value of the voltage feedback signal, the second input terminal of the anomaly detection module serves as the second input terminal of the protection circuit to receive the absolute value of the current feedback signal, the output terminal of the anomaly detection module is connected to the first input terminal of the signal merging module, the anomaly detection module is used to monitor the absolute values ​​of the voltage feedback signal and the current feedback signal in real time, and outputs an anomaly detection signal characterizing the abnormal state when at least one of the absolute values ​​of the voltage feedback signal and the current feedback signal exceeds the corresponding preset threshold; The input terminal of the enable switching module is used to receive the enable status signal, and the output terminal of the enable switching module is connected to the second input terminal of the signal merging module. The enable switching module is used to monitor the enable status signal and output an enable failure signal indicating enable failure when the enable status signal meets the first preset range. The output terminal of the signal merging module serves as the control signal output terminal of the protection circuit. The signal merging module is used to output a shutdown control signal to the disabling control terminal when at least one of the abnormal detection signal and the enable failure signal is detected.

5. The voltage control circuit as described in claim 4, characterized in that, The anomaly detection module includes an anomaly detection unit, a signal broadening unit, and a comparison unit. The first input terminal of the anomaly detection unit receives the absolute value of the voltage feedback signal, and the second input terminal receives the absolute value of the current feedback signal. The input terminal of the signal broadening unit is connected to the output terminal of the anomaly detection unit, and the output terminal of the signal broadening unit is connected to the input terminal of the comparison unit. The output terminal of the comparison unit outputs the anomaly detection signal. The anomaly detection unit is used to output a short-term anomaly signal when at least one of the absolute values ​​of the voltage feedback signal and the current feedback signal exceeds a corresponding preset threshold; the signal broadening unit is used to broaden the short-term anomaly signal to generate a long-term anomaly signal; and the comparison unit is used to output the anomaly detection signal when the long-term anomaly signal is detected to meet a second preset range.

6. The voltage control circuit as described in claim 5, characterized in that, The anomaly detection unit includes an overvoltage detection subunit, an overcurrent detection subunit, and a merging subunit. Wherein, the first input terminal of the overvoltage detection subunit serves as the first input terminal of the protection circuit, the second input terminal of the overvoltage detection subunit is used to receive the first reference voltage, the output terminal of the overvoltage detection subunit is connected to the first input terminal of the merging subunit, and the overvoltage detection subunit is used to output an overvoltage detection signal when the absolute value of the voltage feedback signal is greater than the first reference voltage; The first input terminal of the overcurrent detection subunit serves as the second input terminal of the protection circuit. The second input terminal of the overcurrent detection subunit is used to receive the second reference voltage. The output terminal of the overcurrent detection subunit is connected to the second input terminal of the merging subunit. The overcurrent detection subunit is used to output an overcurrent detection signal when the absolute value of the current feedback signal is greater than the second reference voltage. The output terminal of the merging subunit serves as the output terminal of the anomaly detection module, and the merging subunit is used to output the corresponding anomaly detection signal when at least one of the overvoltage detection signal and the overcurrent detection signal is detected.

7. The voltage control circuit as described in claim 4, characterized in that, The signal merging module includes a first diode, a second diode, and a first resistor. The anode of the first diode serves as the first input terminal of the signal merging module and is connected to the output terminal of the anomaly detection module. The cathode of the first diode is connected to the first terminal of the first resistor. The anode of the second diode serves as the second input terminal of the signal merging module and is connected to the output terminal of the enable switching module. The cathode of the second diode is connected between the cathode of the first diode and the first terminal of the first resistor. The second terminal of the first resistor is grounded, and the first terminal of the first resistor also serves as the output terminal of the signal merging module.

8. The voltage control circuit as described in claim 1, characterized in that, The output terminals of the disability control module include a first output terminal, a second output terminal, and a third output terminal. The disability control module includes a first disability control unit, a second disability control unit, and a third disability control unit. The first, second, and third disability control units are all grounded at their first terminals. The second terminal of the first disability control unit serves as the first output terminal of the disability control module and is connected to the circuit containing the second input terminal of the error amplification module. The second terminal of the second disability control unit serves as the second output terminal of the disability control module and is connected to the circuit containing the output terminal of the error amplification module. The second terminal of the third disability control unit serves as the third output terminal of the disability control module and is connected to the disability pin. The control terminals of the first, second, and third disability control units together serve as the disability control terminals of the voltage conversion circuit.

9. An electrostatic chuck voltage control system, characterized in that, Applications in electrostatic chucks include: A DC power supply is used to output DC power. The voltage control circuit according to any one of claims 1-8 is electrically connected to the electrostatic chuck and the DC power supply, and is used to convert the DC power output by the DC power supply and control the operation of the electrostatic chuck.

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