Electrostatic chuck power supply with independent bias voltage, chucking apparatus, and control method

Abstract

The application belongs to the technical field of semiconductor processing, and particularly relates to an electrostatic chuck power supply with independent bias voltage, a suction device and a control method. The power supply comprises a direct current high voltage module and a first power supply polarity switching module connected in sequence, the first power supply polarity switching module outputs a bipolar voltage used for suction of an electrostatic chuck, and further comprises a control module, a bias voltage module and a second power supply polarity switching module, the output end of the second power supply polarity switching module is electrically connected with the direct current high voltage module; the bias voltage module acquires a direct current input voltage and outputs a bias voltage to the second power supply polarity switching module, the second power supply polarity switching module switches the polarity of the bias voltage and outputs the bias voltage to the direct current high voltage module under the control of the control module, and meanwhile the bias voltage can also be independently output as a voltage source. The bias voltage can meet the dynamic adjustment requirement in the wafer suction process and is suitable for application scenarios requiring independent use of the bias voltage.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor processing, and particularly relates to an electrostatic chuck power supply with independent bias voltage, an adsorption device and a control method. BACKGROUND

[0002] The existing bipolar electrostatic chuck (ESC) power supply technology mainly realizes high-voltage bipolar output by externally injecting a bias voltage and superimposing an adjustable modulation signal. The ESC power supply is a core subsystem in semiconductor manufacturing equipment. The bias voltage externally injected by the ESC power supply is only used for internal power voltage lifting and cannot be used as a voltage source output alone. For wafer adsorption in some special conditions, such as the need for an ESC power supply to have an internal bias voltage and the need to use the bias voltage as a voltage source output alone, the existing ESC power supply technology cannot meet the requirements, and an electrostatic chuck power supply capable of providing an additional independent voltage source is needed. SUMMARY

[0003] The application is proposed to meet the need for dynamic adjustment of the size and polarity of the bias voltage during wafer adsorption and the need for an additional voltage in some scenarios.

[0004] In one aspect, the electrostatic chuck power supply with independent bias voltage provided by the application comprises a direct-current high-voltage module and a first power supply polarity switching module connected in sequence, and the first power supply polarity switching module outputs a bipolar voltage used for adsorbing an electrostatic chuck. The electrostatic chuck power supply further comprises a control module, a bias voltage module and a second power supply polarity switching module, and the output end of the second power supply polarity switching module is electrically connected with the direct-current high-voltage module.

[0005] The bias voltage module is used to obtain a direct-current input voltage and output a bias voltage to the second power supply polarity switching module. The second power supply polarity switching module switches the polarity of the bias voltage under the control of the control module and outputs the bias voltage to the direct-current high-voltage module. Meanwhile, the bias voltage can also be output as a voltage source alone.

[0006] The electrostatic chuck power supply with independent bias voltage provided by the above scheme additionally comprises a bias voltage module. To increase the bias voltage module, a control module and a second power supply polarity switching module are matched. The voltage output by the bias voltage module can be input to the direct-current high-voltage module to meet the need for dynamic adjustment of the size and polarity of the bias voltage during wafer adsorption. Meanwhile, the bias voltage module can also output the bias voltage independently of the original bipolar electrostatic chuck power supply. At this time, the bias voltage can be output as a voltage source alone, which is suitable for various application scenarios that require a voltage source alone.

[0007] Preferably, the bias voltage module comprises an inverter unit, a resonant transformer unit and a voltage doubling rectifier unit connected in sequence, for converting a direct current input voltage into a positive bias voltage and a negative bias voltage. The internal structure of the bias voltage module is specifically disclosed, and the unipolar direct current voltage is converted into a positive bias voltage and a negative bias voltage by the inverter unit, the resonant transformer unit and the voltage doubling rectifier unit, so as to provide multiple selectable types for the subsequent output voltage.

[0008] Preferably, the output end of the second power supply polarity switching module is electrically connected with the second tap of the secondary side of the transformer in the direct current high voltage module, for inputting the bias voltage to the direct current high voltage module. The second power supply polarity switching module is used for switching the output voltage of the bias voltage module, and the bias voltage is output to the direct current high voltage module or independently output.

[0009] Preferably, the control module is electrically connected with the direct current high voltage module, the bias voltage module, the first power supply polarity switching module and the second power supply polarity switching module respectively, for collecting the voltage and current feedback signals output by the direct current high voltage module and the bias voltage module respectively, and controlling the output of the direct current high voltage module and the bias voltage module. The control module serves as a control center, controls the output of the bipolar electrostatic chuck power supply, collects the output parameters, confirms the working state, and ensures that the entire circuit inputs or outputs according to the preset logic.

[0010] Preferably, the first power supply polarity switching module and the second power supply polarity switching module switch on or off according to the control signal output by the control module, and control the polarity of the output voltage of the direct current high voltage module and the bias voltage module. The first power supply polarity switching module is used for switching the output of the bipolar adsorption voltage according to the original bipolar electrostatic chuck power supply, and the second power supply polarity switching is used for switching the output link of the newly added bias voltage. The two switching modules cooperate with each other to realize multiple output states of the electrostatic chuck power supply.

[0011] Preferably, the second power supply polarity switching module comprises a polarity switching unit and a discharging unit connected in sequence.

[0012] The polarity switching unit comprises a first switch and a second switch, the input ends of the first switch and the second switch are connected with the positive polarity output end and the negative polarity output end of the bias voltage module respectively, the output ends of the first switch and the second switch are connected and led out as the output end of the second power supply polarity switching module, and the polarity switching of the bias voltage is realized by controlling the on-off of the first switch and the second switch.

[0013] The discharge unit comprises a discharge switch, an input terminal of the discharge switch is connected to the output terminal, and an output terminal is grounded, and the discharge switch is used for discharging the bias voltage module.

[0014] Based on the same concept, an electrostatic chuck adsorption device with independent bias voltage is also proposed, which comprises an adsorption component and an electrostatic chuck power supply with independent bias voltage as claimed in any one of the above.

[0015] In another aspect, the embodiment of the present application provides a control method of the electrostatic chuck power supply with independent bias voltage, which adopts the electrostatic chuck power supply with independent bias voltage as claimed in any one of the above; a control module outputs a bias voltage control signal to the bias voltage module, and the bias voltage module outputs a bias voltage to the direct current high voltage module, and the bias voltage can also be output as a voltage source independently.

[0016] Compared with the prior art, the present application has the beneficial effects that: the present application provides the electrostatic chuck power supply with independent bias voltage, additionally increases the bias voltage module, the voltage output by the bias voltage module can meet the demand of dynamic adjustment of voltage in the wafer adsorption process, and is suitable for application scenarios requiring independent use of bias voltage. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A block diagram of the electrostatic chuck power supply with independent bias voltage in the embodiment 1 of the present application;

[0018] Figure 2 A schematic diagram of the internal structure of the direct current high voltage module and the bias voltage module in the embodiment 1 of the present application;

[0019] Figure 3 The electrostatic chuck power supply with independent bias voltage in the embodiment 1 of the present application after refinement of the scheme;

[0020] Figure 4 A circuit diagram of the electrostatic chuck power supply with independent bias voltage in the embodiment 2 of the present application;

[0021] Figure 5 A circuit diagram of an optimized electrostatic chuck power supply with independent bias voltage in the embodiment 2 of the present application;

[0022] Figure 6 A schematic diagram of the H-bridge inverter principle of the switch tube in the embodiment 2 of the present application;

[0023] Figure 7 A schematic diagram of the H-bridge switch tube driving principle in the embodiment 2 of the present application;

[0024] Figure 8 An H-bridge driving waveform in the embodiment 2 of the present application;

[0025] Figure 9 Figure 2 is a schematic diagram of a power supply polarity switching module relay switching output polarity in embodiment 2 of the present application. DETAILED DESCRIPTION

[0026] The present application will be further described in details with reference to the following test examples and embodiments. However, it should not be understood that the scope of the above-mentioned subject matter of the present application is limited to the following examples only, and any technology realized based on the content of the present application falls within the scope of the present application.

[0027] In the description of the specific embodiments of the present application, the orientation or positional relationship terms such as "up", "down", "left", "right", "center", "inner", "outer", "side" and the like appear without special indication, are expressed based on the orientation or positional relationship shown in the drawings, or are the orientation or positional relationship when the product / device / apparatus is usually used. These orientation or positional relationship terms are only for the convenience of describing the present application scheme or simplifying the description in the specific embodiments, for the convenience of the technical personnel to quickly understand the scheme, and cannot be understood as indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship, and therefore cannot be understood as a limitation on the present application.

[0028] In the description of the embodiments of the present application, the technical terms "first", "second" and the like only distinguish one entity or operation from another entity or operation, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is two and more than two, unless otherwise specifically limited.

[0029] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that the embodiments described herein are merely examples and it is expressly contemplated that the embodiments can be combined or otherwise combined with other embodiments.

[0030] The bipolar electrostatic chuck (ESC) power supply technology mainly realizes high-voltage bipolar output by superimposing an adjustable modulation signal on a fixed polarity bias voltage. The bipolar power supply is used for adsorption or release of adsorption of the electrostatic chuck. The application of the fixed polarity bias voltage has limitations, that is, it can only be used for internal power supply voltage lifting to realize the output of the bipolar high voltage. In actual application scenarios, there are corresponding other functions that require bias voltage, such as: additional voltage is required for initial pre-adsorption or safe release; additional voltage is required for detection or calibration mode; additional voltage is required for sensitive material processing, and the like. Therefore, the present application provides a new concept of an electrostatic chuck power supply with an independent bias voltage, an adsorption device and a control method. On the basis of the existing bipolar electrostatic chuck power supply, a bias voltage module is added for independently outputting an additional voltage to meet the demand for dynamically adjusting the voltage in the wafer adsorption process and the situation that multiple devices require bias voltage in actual application scenarios.

[0031] Embodiment 1

[0032] Please refer to Figure 1 , Figure 1 The electrostatic chuck power supply with an independent bias voltage provided by the embodiment of the present application comprises a direct-current high-voltage module and a first power supply polarity switching module connected in sequence, the first power supply polarity switching module outputs a bipolar voltage used for adsorbing an electrostatic chuck, further comprises a control module, a bias voltage module and a second power supply polarity switching module, the output end of the second power supply polarity switching module is electrically connected with the direct-current high-voltage module; the bias voltage module obtains a direct-current input voltage and outputs a bias voltage to the second power supply polarity switching module, the second power supply polarity switching module switches the polarity of the bias voltage and outputs it to the direct-current high-voltage module under the control of the control module, and the bias voltage can also be independently output as a voltage source.

[0033] As can be seen from Figure 1 , the bias voltage module obtains a direct-current input voltage and outputs a bias voltage to the second power supply polarity switching module, the second power supply polarity switching module switches the polarity of the bias voltage and outputs it to the direct-current high-voltage module under the control of the control module, and the bias voltage can also be independently output as a voltage source. Whether the bias voltage is output in which polarity, whether the bias voltage is independently output or output to the direct-current high-voltage module is controlled by the second power supply polarity switching module.

[0034] The direct-current high-voltage module is mainly used for converting a unipolar voltage into a bipolar voltage, and the bias voltage module has a similar function to the direct-current high-voltage module, so the internal structures of the two are the same. The internal structure diagram of the direct-current high-voltage module and the bias voltage module is as shown in Figure 2As shown, the high-voltage direct-current module includes an inverter unit, a resonant transformer unit and a voltage doubling rectifier unit connected in sequence, and the high-voltage direct-current module is used to convert a direct-current input voltage into a positive polarity voltage and a negative polarity voltage, and the bias voltage module is used to convert the direct-current input voltage into a positive polarity bias voltage and a negative polarity bias voltage.

[0035] The high-voltage direct-current module outputs the positive polarity voltage and the negative polarity voltage, and the bias voltage module outputs the positive polarity bias voltage and the negative polarity bias voltage, and on this basis, the final output voltage state and the power supply polarity switching module are closely related. The first power supply polarity switching module switches on or off according to the control signal output by the control module, controls the high-voltage direct-current module to output the bipolar voltage, and is used for wafer adsorption by the electrostatic chuck. Further, the output end of the second power supply polarity switching module is electrically connected with the second tap of the transformer in the high-voltage direct-current module, and is used to output the positive polarity bias voltage or the negative polarity bias voltage output by the bias voltage module to the high-voltage direct-current module, and is used to dynamically adjust the bias voltage size and polarity during wafer adsorption. The second power supply polarity switching module can also be used to output the positive polarity bias voltage or the negative polarity bias voltage as a voltage source alone.

[0036] The entire electrostatic chuck power supply with independent bias voltage needs a control module to realize the monitoring of the state of the high-voltage direct-current module and the bias voltage module and the switching of the switches in the first power supply polarity switching module and the second power supply polarity switching module, and therefore, preferably, the control module includes an analog-to-digital conversion unit, a programmable unit, a communication unit and the like, and is electrically connected with the high-voltage direct-current module, the bias voltage module, the first power supply polarity switching module and the second power supply polarity switching module respectively, and is used to collect the voltage feedback signal and the current feedback signal output by the high-voltage direct-current module and the bias voltage module respectively, and adjust the output of the high-voltage direct-current module and the bias voltage module by controlling the state of the first power supply polarity switching module and the second power supply polarity switching module.

[0037] The internal structure diagram of the first power supply polarity switching module and the second power supply polarity switching module is as shown in Figure 3 The second power supply polarity switching module is shown in the lower half of Figure 3 and includes a polarity switching unit and a discharge unit connected in sequence.

[0038] The polarity switching unit includes a switch K7 and a switch K8, the line-in ends of the switch K7 and the switch K8 are connected with the positive polarity output end and the negative polarity output end of the bias voltage module respectively, the line-out ends of the switch K7 and the switch K8 are connected and led out, and serve as the output end of the second power supply polarity switching module, and output as HVCT out, and the polarity switching of the output bias voltage HVCT out is realized by controlling the conduction and the shutdown of the switch K7 and the switch K8.

[0039] The discharge unit comprises a discharge switch K9 and a discharge circuit, the input terminal of the discharge switch K9 is connected to the output terminal HVCTout, and the output terminal is grounded, and is used for discharging the bias voltage module.

[0040] The first power supply polarity switching module is shown in the upper half of Figure 3 , comprising a plurality of switches and a discharge circuit. The switches K1, K2, K3 and K4 constitute a wafer residual charge processing circuit, K3 / K4 and K1 / K2 are two groups of switches that are turned on and turned off at the same time, when K3 / K4 is closed and K1 / K2 is disconnected, HV+ and HV- are output according to the corresponding positive and negative polarity, otherwise, the polarity of HV+ and HV- is exchanged, and the wafer residual charge is neutralized through circuit commutation; the discharge circuit is electrically connected to HV+ and HV- through K5 and K6 respectively, and the midpoint of the discharge circuit is grounded, K5 and K6 are discharge switches, which are closed after the input of the closing voltage, and the electrostatic chuck is discharged to the ground through the discharge circuit. As a specific embodiment, the discharge circuit is realized by a discharge resistor.

[0041] On the other hand, the application provides a control method of the electrostatic chuck power supply with independent bias voltage, which adopts the electrostatic chuck power supply with independent bias voltage as described in any one of the above;

[0042] The control module outputs a bias voltage control signal to the bias voltage module, and the bias voltage module outputs a bias voltage to the direct current high voltage module, and the bias voltage can also be output as a voltage source independently.

[0043] The application designs an electrostatic chuck power supply which can realize bias voltage polarity reversal and independent output, can meet the needs of dynamically adjusting the size and polarity of the bias voltage during wafer adsorption, and can meet the requirements of using the bias voltage independently.

[0044] Embodiment 2

[0045] The refined electrostatic chuck power supply with independent bias voltage is shown in Figure 4 , in combination with Figure 3 and Figure 4 , the functions of each module are as follows:

[0046] The direct current high voltage module is connected to the control module, the bias voltage module and the power supply polarity switching module, and is used for converting the input 24V direct current bus voltage into 0~+1500V and 0~-1500V output according to the control signal output by the control module, wherein the center point is connected to the bias voltage module, and the voltage difference between the two outputs to the ground can be changed by the bias voltage module, and the positive and negative high voltage can be switched by the first power supply polarity switching module to finally output the polarity.

[0047] The bias voltage module is connected with the control module, the direct current voltage module and the second power supply polarity switching module, and is used for converting the input 24V direct current bus voltage into a bias voltage of 0~±500V according to the control signal output by the control module, and outputting two-way voltage to the second power supply polarity switching module, switching into a single-way bias voltage of a corresponding polarity according to the polarity requirement, and injecting into the direct current high voltage module and separately outputting.

[0048] The power supply polarity switching module includes a first power supply polarity switching module and a second power supply polarity switching module, both of which are connected with the control module, the first power supply polarity switching module is connected with the direct current high voltage module, and the second power supply polarity switching module is connected with the bias voltage module, and is used for switching the output polarity of the direct current high voltage module and the bias voltage module according to the control signal output by the control module, and sending the output voltage and current collection signal of the direct current high voltage module and the bias voltage module to the control module after operational amplification calculation. Further, the second power supply polarity switching module also has a discharging function, and the relay is connected with a discharging resistor to the ground, and the discharging function is realized by controlling the switch of the relay.

[0049] The control module is connected with the direct current high voltage module, the bias voltage module and the power supply polarity switching module, and is used for sending a driving signal to the direct current high voltage module and the bias voltage module to control the output thereof, receiving an overheating signal, sending a relay control signal to the power supply polarity switching module to switch the output polarity of the direct current high voltage module and the bias voltage module, and receiving the voltage and current feedback signal sent from the power supply polarity switching module.

[0050] The main circuit working principle is that: at the moment when the equipment is started, it is assumed that the driving signal has been established, the driving voltage of the switch tube has been generated, the bus voltage is inverted into an alternating voltage through the inverter unit in the direct current high voltage module, the alternating voltage is transmitted to the secondary circuit of the transformer through the transformer in the resonant transformer unit, the secondary circuit is a voltage doubling rectifier unit, the voltage doubling rectifier unit converts the alternating voltage into a direct current voltage, and outputs positive and negative direct current high voltage HV+ and HV-. The positive and negative direct current high voltage passes through the relay in the first power supply polarity switching module to switch the polarity, and the switching of the two output channels can be realized. In addition, in the bias voltage module, the bus voltage is inverted into an alternating voltage through the inverter unit in the bias voltage module, the alternating voltage is transmitted to the secondary circuit of the transformer through the transformer in the resonant transformer unit, the secondary circuit is a voltage doubling rectifier unit, the voltage doubling rectifier unit converts the alternating voltage into a direct current voltage, and outputs positive and negative direct current bias voltage. However, the bias voltage module finally outputs a single polarity voltage, and the output of the positive direct current bias voltage or the negative direct current bias voltage is determined by the switch in the second power supply polarity switching module.

[0051] The working principle of the control module is summarized as follows: the actual output voltage and current of the load are subtracted from the set voltage and current value, and the obtained result is subjected to PID closed-loop control to output a control signal to the inverter unit. The inverter unit is preferably a full-bridge inverter circuit, and the duty cycle of the PWM waveform is used to control the conduction and turn-off of the switching tubes in the full-bridge inverter circuit, so as to realize the adjustment of the output parameters of the full-bridge inverter circuit.

[0052] Under the control of the control module, the working principle of polarity switching is as follows: for the DC high-voltage module, when the relays K1 and K2 are disconnected and K3 and K4 are closed, the output polarity is positive on the upper side and negative on the lower side; when the relays K1 and K2 are closed and K3 and K4 are disconnected, the output polarity is negative on the upper side and positive on the lower side. For the bias voltage module, when the relay K7 is closed and K8 is disconnected, the output polarity is positive; when the relay K7 is disconnected and K8 is closed, the output polarity is negative. K5, K6 and K9 are all relays in the discharge circuit, and closing them will discharge.

[0053] Through the driving control and polarity switching control, the desired output combination can be realized, that is, the positive and negative polarity high-voltage output of different voltages is matched with the positive and negative polarity bias voltage of different voltages, which can be flexibly applied to various wafer adsorption processes.

[0054] Embodiment 3

[0055] Embodiment 3 further discloses the specific circuit diagrams of the DC bias module, the power supply polarity switching module and the DC high-voltage module and the implementation means on the basis of embodiment 2. An optimized circuit diagram of an electrostatic chuck power supply with independent bias voltage is shown in Figure 5 .

[0056] The H-bridge inverter principle diagram of the switching tube is shown in Figure 6 , Figure 6 which embodies the concept of the entire circuit. The control chip of the control module adopts DSP, the communication interface adopts EtherCAT, the analog-to-digital conversion adopts the ADC module, the inverter circuit adopts the H-bridge switching tube, and the H-bridge switching tube driving principle diagram is shown in Figure 7 , the H-bridge driving waveform is shown in Figure 8 , and the working principle is as follows: high level is input to the switching tubes Q1 and Q4 at the same time, the switching tubes Q1 and Q4 are opened, the switching tubes Q2 and Q3 are closed, then all four switching tubes are closed, in the next cycle, high level is input to the switching tubes Q3 and Q2, the switching tubes Q3 and Q2 are opened, the switching tubes Q1 and Q4 are closed, then all four switching tubes are closed, and the cycle is repeated in the next cycle. The schematic diagram of the relay switching output polarity in the power supply polarity switching module is shown in Figure 9 . According to the H-bridge driving waveform, a sawtooth wave is generated.

[0057] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not limit them; although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. An electrostatic chuck power supply with an independent bias voltage, comprising a DC high-voltage module and a first power supply polarity switching module connected in sequence, wherein the first power supply polarity switching module outputs a bipolar voltage for attracting the electrostatic chuck, characterized in that, It also includes a control module, a bias voltage module, and a second power supply polarity switching module, the output of which is electrically connected to the DC high voltage module. The bias voltage module is used to acquire the DC input voltage and output the bias voltage to the second power supply polarity switching module. Under the control of the control module, the second power supply polarity switching module switches the polarity of the bias voltage and outputs the bias voltage to the DC high voltage module. At the same time, the bias voltage can also be output as a voltage source independently.

2. The electrostatic chuck power supply with independent bias voltage as described in claim 1, characterized in that, The bias voltage module includes an inverter unit, a resonant transformer unit, and a voltage doubler rectifier unit connected in sequence, used to convert the DC input voltage into a positive bias voltage or a negative bias voltage.

3. The electrostatic chuck power supply with independent bias voltage as described in claim 1, characterized in that, The output terminal of the second power polarity switching module is electrically connected to the second tap on the secondary side of the transformer in the DC high voltage module, and is used to input the bias voltage to the DC high voltage module.

4. The electrostatic chuck power supply with independent bias voltage as described in claim 1, characterized in that, The control module is electrically connected to the DC high voltage module, the bias voltage module, the first power supply polarity switching module, and the second power supply polarity switching module, respectively, and is used to collect the voltage feedback signal and current feedback signal output by the DC high voltage module and the bias power supply module, respectively, and control the output of the DC high voltage module and the bias voltage module.

5. The electrostatic chuck power supply with independent bias voltage as described in claim 4, characterized in that, The first power polarity switching module and the second power polarity switching module switch on or off according to the control signal output by the control module, thereby controlling the polarity of the output voltage of the DC high voltage module and the bias voltage module.

6. The electrostatic chuck power supply with independent bias voltage as described in claim 5, characterized in that, The second power polarity switching module includes a polarity switching unit and a discharge unit connected in sequence; The polarity switching unit includes a first switch and a second switch. The input terminals of the first switch and the second switch are respectively connected to the positive polarity output terminal and the negative polarity output terminal of the bias voltage module. The output terminals of the first switch and the second switch are connected and led out, serving as the output terminal of the second power supply polarity switching module. The polarity switching of the bias voltage is achieved by controlling the on and off states of the first switch and the second switch. The discharge unit includes a discharge switch and a bleed resistor. The input terminal of the discharge switch is connected to the output terminal, and the output terminal is grounded after passing through the bleed resistor, for discharging the bias voltage module.

7. An electrostatic chuck adsorption device with an independent bias voltage, characterized in that, It includes an adsorption component and an electrostatic chuck power supply with an independent bias voltage as described in any one of claims 1-6.

8. A control method for an electrostatic chuck power supply with an independent bias voltage, characterized in that, The electrostatic chuck power supply with independent bias voltage as described in any one of claims 1-6 is used; The control module outputs a bias voltage control signal to the bias voltage module, and the bias voltage module outputs a bias voltage to the DC high voltage module. At the same time, the bias voltage can also be output as a voltage source independently.

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