Electrostatic chuck power supply and control method

Abstract

The present invention provides an electrostatic chuck power supply and control method. The method includes a detection module and a control module, wherein the detection module is connected to the control module; the detection module is used to connect to the electrostatic chuck, send a detection signal to the electrostatic chuck, collect a response signal returned by the detection signal after passing through the electrostatic chuck, and send the response signal to the control module; the control module is used to determine the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal. The present invention can determine the wafer adsorption state of the electrostatic chuck by using the corresponding relationship between the change of the detection signal and the clamping degree between the wafer and the electrostatic chuck.

Description

Technical Field

[0001] The present invention relates to the technical field of electrostatic chucks, and in particular to an electrostatic chuck power supply and a control method. Background Art

[0002] The electrostatic chuck power supply is a DC power supply with high voltage and low current output. The electrostatic chuck power supply is connected to the ESC electrode of the Coulomb type electrostatic chuck. By controlling the on and off of the power supply and utilizing the principle of polarized charge generated on the surface of the dielectric, an electrostatic field can be generated between the electrostatic chuck and the wafer to achieve adsorption and release of the wafer.

[0003] In actual wafer processing projects, the wafer must be firmly adsorbed to the surface of the chuck. On the one hand, this increases the heat conduction between the wafer and the chuck, and on the other hand, it prevents movement and misalignment, thereby reducing the breakage rate. Therefore, it is extremely important to detect the adsorption state between the wafer and the chuck. Summary of the invention

[0004] The embodiment of the present invention provides an electrostatic chuck power supply and control method to solve the problem of detecting the adsorption state between a wafer and an electrostatic chuck.

[0005] In a first aspect, an embodiment of the present invention provides an electrostatic chuck power supply, including a detection module and a control module, wherein the detection module is connected to the control module;

[0006] The detection module is used to connect with the electrostatic chuck, send a detection signal to the electrostatic chuck, collect a response signal returned by the detection signal after passing through the electrostatic chuck, and send the response signal to the control module;

[0007] The control module is used to determine the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal.

[0008] In a possible implementation, the detection signal is a sine wave signal; the detection module includes a sine wave generating circuit, a rectifier filtering circuit and a DC voltage sampling circuit;

[0009] The input end of the sine wave generating circuit is connected to the control module, and the output end is used to connect to the electrostatic chuck. The input end of the rectifier and filter circuit is used to connect to the electrostatic chuck, and the output end is connected to the input end of the DC voltage sampling circuit. The output end of the DC voltage sampling circuit is connected to the control module.

[0010] The sine wave generating circuit is used for sending a sine wave signal to the electrostatic chuck;

[0011] The rectifier and filter circuit is used to rectify and filter the response signal returned by the sine wave signal after passing through the electrostatic chuck to obtain a DC response signal;

[0012] The DC voltage sampling circuit is used to perform DC voltage sampling on the DC response signal, obtain a DC voltage sampling value of the DC response signal, and send it to the control module.

[0013] In a possible implementation, the control module is specifically used to:

[0014] If the DC voltage sampling value of the DC response signal is within the first preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is that the wafer is present but not adsorbed;

[0015] If the DC voltage sampling value of the DC response signal is within the second preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is adsorption;

[0016] If the DC voltage sampling value of the DC response signal is within the third preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is released; wherein the first preset interval < the second preset interval < the third preset interval.

[0017] In a possible implementation, the control module is specifically used to:

[0018] Calculating the capacitance value of the electrostatic chuck based on the sine wave signal and the DC voltage sampling value;

[0019] The wafer adsorption state of the electrostatic chuck is determined based on the capacitance value of the electrostatic chuck.

[0020] In a possible implementation, it also includes a power supply module;

[0021] The power supply module is used to connect with the electrostatic chuck and provide power to the electrostatic chuck.

[0022] In a possible implementation, the power supply module is connected to the control module;

[0023] The control module is also used to send a power supply state adjustment instruction to the power supply module based on the wafer adsorption state of the electrostatic chuck to adjust the wafer adsorption state of the electrostatic chuck.

[0024] In a second aspect, an embodiment of the present invention provides a control method for an electrostatic chuck power supply, which is applied to an electrostatic chuck power supply, wherein the electrostatic chuck power supply includes a detection module and a control module; the method includes:

[0025] The detection module sends a detection signal to the electrostatic chuck, collects a response signal returned by the detection signal after passing through the electrostatic chuck, and sends the response signal to the control module;

[0026] The control module determines a wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal.

[0027] An embodiment of the present invention provides an electrostatic chuck power supply and control method, which sends a detection signal to the electrostatic chuck, collects a response signal returned after the detection signal passes through the electrostatic chuck, compares the detection signal with the response signal, and determines the change of the detection signal after passing through the electrostatic chuck, thereby using the corresponding relationship between the change of the detection signal and the clamping degree between the chip and the electrostatic chuck to determine the chip adsorption state of the electrostatic chuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0029] Figure 1 is a schematic diagram of the structure of an electrostatic chuck power supply provided by an embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of charge distribution of an electrostatic chuck provided by an embodiment of the present invention;

[0031] Figure 3 is a schematic diagram of a detection signal transmission path provided by an embodiment of the present invention;

[0032] Figure 4 is a schematic diagram of the structure of an electrostatic chuck power supply provided by another embodiment of the present invention;

[0033] Figure 5 It is a flow chart of an implementation method of a control method of an electrostatic chuck power supply provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0034] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0036] See also Figure 1 , which shows a schematic diagram of the structure of an electrostatic chuck power supply provided by an embodiment of the present invention, the electrostatic chuck power supply includes a detection module 11 and a control module 12, and the detection module 11 is connected to the control module 12;

[0037] The detection module 11 is used to connect with the electrostatic chuck, send a detection signal to the electrostatic chuck, collect a response signal returned by the detection signal after passing through the electrostatic chuck, and send the response signal to the control module 12;

[0038] The control module 12 is used to determine the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal.

[0039] In this embodiment, the charge distribution state of the electrostatic chuck after power is applied is as follows: Figure 2 As shown, the capacitance between the wafer and the chuck changes with the degree of clamping between the two. The capacitance is smallest when there is no wafer, and is largest when there is a wafer and a DC power supply is turned on. Therefore, the capacitance between the wafer and the chuck can be determined by the detection signal, and then the degree of clamping between the wafer and the chuck, that is, the wafer adsorption state of the electrostatic chuck, can be determined.

[0040] The corresponding relationship between the change of the detection signal and the clamping degree between the wafer and the electrostatic chuck can be determined through experiments.

[0041] Based on the above principle, the capacitance critical value can be set through the program according to different chip types and sizes. That is, if it exceeds the set critical value, it means that the chip is firmly adsorbed to the electrostatic chuck and the chip can be processed.

[0042] The embodiment of the present invention sends a detection signal to the electrostatic chuck, collects a response signal returned after the detection signal passes through the electrostatic chuck, compares the detection signal with the response signal, and determines the change of the detection signal after passing through the electrostatic chuck, thereby determining the wafer adsorption state of the electrostatic chuck based on the correspondence between the change of the detection signal and the clamping degree between the wafer and the electrostatic chuck.

[0043] In a possible implementation, the detection signal is a sine wave signal; the detection module 11 includes a sine wave generating circuit, a rectifier filtering circuit and a DC voltage sampling circuit;

[0044] The input end of the sine wave generating circuit is connected to the control module 12, and the output end is used to connect to the electrostatic chuck. The input end of the rectifier filter circuit is used to connect to the electrostatic chuck, and the output end is connected to the input end of the DC voltage sampling circuit. The output end of the DC voltage sampling circuit is connected to the control module 12;

[0045] The sine wave generating circuit is used for sending a sine wave signal to the electrostatic chuck;

[0046] The rectifier and filter circuit is used to rectify and filter the response signal returned by the sine wave signal after passing through the electrostatic chuck to obtain a DC response signal;

[0047] The DC voltage sampling circuit is used to perform DC voltage sampling on the DC response signal, obtain a DC voltage sampling value of the DC response signal, and send the DC voltage sampling value to the control module 12 .

[0048] In this embodiment, the existing capacitance detection scheme mainly includes the following two methods:

[0049] 1. Resonance principle: When an inductor or capacitor forms a resonant circuit, the resonant frequency is determined by the inductor and capacitor. Measure the resonant frequency to obtain the inductor or capacitor value. Since the loss resistance of the inductor or capacitor will affect the measurement result, the loss (or Q value) of the resonant circuit should be measured indirectly to correct the effect on the frequency to obtain a more accurate result.

[0050] 2. AC bridge principle: The measured inductance or capacitance is used as one arm of the bridge, and the value of the compensation bridge arm is changed to balance the bridge. Thus, the inductance and capacitance values ​​are measured. Similarly, the error caused by the loss of inductance and capacitance on the measurement should be considered, and a compensation resistor should be added to the compensation bridge arm.

[0051] The above two solutions have large pulsation noise, require the use of filters and consider phase compensation, the circuit structure is relatively complex, and the cost is also high.

[0052] In this regard, the present embodiment utilizes the high-pass and low-resistance characteristics of capacitors for alternating current. When a sine wave with a fixed frequency and amplitude passes through capacitors with different capacitance values, different voltage drops are generated. Figure 3 The signal transmission block diagram shown in the figure controls the sine wave signal as the detection signal to be input from one end of the electrostatic chuck, and output from the other end and pass through the rectifier circuit. According to the output DC voltage value, it indicates the states of no wafer, wafer, wafer adsorption and wafer release. Under the condition of applying variable high voltage (0.5KV~5KV) on the electrostatic chuck, the change of a small capacitor is detected to accurately judge the wafer adsorption state of the electrostatic chuck.

[0053] In a possible implementation, the control module 12 is specifically configured to:

[0054] If the DC voltage sampling value of the DC response signal is within the first preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is that the wafer is present but not adsorbed;

[0055] If the DC voltage sampling value of the DC response signal is within the second preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is adsorption;

[0056] If the DC voltage sampling value of the DC response signal is within the third preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is released; wherein the first preset interval < the second preset interval < the third preset interval.

[0057] In this embodiment, the judgment interval of the DC voltage sampling value can be directly set. When the DC voltage sampling value falls within a certain interval, it means that the adsorption state of the electrostatic chuck is consistent with the adsorption state represented by this interval. As the wafer size and the electrostatic chuck size are different, the various judgment intervals of the DC voltage sampling value will also change. The judgment threshold of the wafer adsorption state can be set according to the wafer size (6 inches, 8 inches, 12 inches), and the adsorption strength can be controlled based on this.

[0058] An adsorption state judgment interval experiment was conducted on a certain type of wafer, and the experimental data obtained are as follows:

[0059] 1. When there is no chip on the electrostatic chuck (no chip), the corresponding capacitance value is 0nF and the output DC voltage value is 0V;

[0060] 2. When there is a chip on the electrostatic chuck and the power is not turned on (with a chip), the corresponding capacitance value is about 0.5~2.5nF, and the output DC voltage value is about 1~2V;

[0061] 3. When there is a chip on the electrostatic chuck and the power is turned on (adsorption state), the corresponding capacitance value is about 4nF and the output DC voltage value is about 3V;

[0062] 4. When there is a wafer on the electrostatic chuck and the power is disconnected (released state), the corresponding capacitance value is about 3.5nF and the output DC voltage value is about 2.5V;

[0063] 5. The capacitance threshold can be set by program to determine whether the wafer and the electrostatic chuck are completely adsorbed.

[0064] It can be seen from the above that when there is no chip, the capacitance value is 0, and the first preset interval is less than the second preset interval and less than the third preset interval.

[0065] According to experimental data, the state between the wafer and the electrostatic chuck corresponds to different capacitance values. After sampling and calculation by the MCU inside the ESC power supply, the state between the wafer and the electrostatic chuck can be monitored in real time, and appropriate response measures can be taken in time to effectively reduce the wafer breakage rate.

[0066] In a possible implementation, the control module 12 is specifically configured to:

[0067] Calculating the capacitance value of the electrostatic chuck based on the sine wave signal and the DC voltage sampling value;

[0068] The wafer adsorption state of the electrostatic chuck is determined based on the capacitance value of the electrostatic chuck.

[0069] In this embodiment, the voltage drop generated by the sine wave signal after passing through the capacitor formed by the electrostatic chuck and the wafer can be calculated using the sine wave signal and the DC voltage sampling value, and the capacitance of the capacitor formed by the electrostatic chuck and the wafer can be calculated based on this. For a common parallel plate capacitor, the capacitance calculation formula is C=εS / d. (ε is the dielectric constant of the medium between the plates, S is the plate area, and d is the distance between the plates)

[0070] The electrode of the electrostatic chuck and the wafer form a capacitor, and the distance between the electrode and the wafer is different, and the capacitance value will change slightly:

[0071] When there is no chip on the electrostatic chuck (no chip), the corresponding capacitance value is C 无 ;

[0072] When there is a chip on the electrostatic chuck and the high voltage power supply is not connected (chip is present), the corresponding capacitance value is C 有 ;

[0073] When there is a chip on the electrostatic chuck and the high voltage power supply is turned on (adsorption state), the corresponding capacitance value is C 吸附 ;

[0074] When there is a wafer on the electrostatic chuck and the high voltage power supply is turned off (release state), the corresponding capacitance value is C 释放 ;

[0075] The relationship between the capacitance values ​​in each state is as follows:

[0076] C 吸附 >C 释放 >C 有 >C 无

[0077] In a possible implementation, it also includes a power supply module;

[0078] The power supply module is used to connect with the electrostatic chuck and provide power to the electrostatic chuck.

[0079] In this embodiment, the electrostatic chuck power supply can provide stable power output for the electrostatic chuck used for semiconductor wafer transfer. It is a DC power supply with high output voltage and low current, and is divided into unipolar and bipolar types. The power supply module is used to realize the function of the electrostatic chuck power supply to supply power to the electrostatic chuck.

[0080] like Figure 4As shown, the positive and negative electrodes of the bipolar power supply module are respectively connected to the two ends of the electrostatic chuck to provide a higher voltage to the electrostatic chuck; at the same time, the output end of the detection module, that is, the output end of the sine wave generating circuit, and the positive electrode of the power supply module are simultaneously connected to one end of the electrostatic chuck to input the sine wave signal into the electrostatic chuck, and the input end of the detection module, that is, the input end of the rectifier and filter circuit, and the negative electrode of the power supply module are simultaneously connected to the other end of the electrostatic chuck to collect the response signal returned by the sine wave signal after passing through the electrostatic chuck.

[0081] In addition, considering the high power supply voltage, the detection signal adopts a low voltage sine wave to reduce the impact on the operation of the electrostatic chuck. The amplitude of the sine wave can be determined based on experiments.

[0082] The power supply module can also have the following functions:

[0083] 1. Built-in current limiting and protection circuit design reduces power storage energy and protects equipment from damage caused by surges and arcs.

[0084] 2. The positive and negative pole swapping function is set to reduce the risk of residual charge on the chuck by converting the output polarity.

[0085] 3. Add short circuit and open circuit functions to improve the reliability of the equipment.

[0086] 4. Outstanding clamping performance makes this product more suitable for semiconductor wafer production process.

[0087] In a possible implementation, the power supply module is connected to the control module 12;

[0088] The control module 12 is further configured to send a power supply state adjustment instruction to the power supply module based on the wafer adsorption state of the electrostatic chuck, so as to adjust the wafer adsorption state of the electrostatic chuck.

[0089] In this embodiment, the voltage level provided by the electrostatic chuck power supply will affect the adsorption strength of the electrostatic chuck. When the wafer adsorption state of the electrostatic chuck does not meet the requirements, the power supply voltage can be adjusted to adjust the wafer adsorption state of the electrostatic chuck.

[0090] After determining whether the chip is adsorbed, the control module can send the adsorption status to the client. After the client confirms that the chip is adsorbed, the chip can be processed, such as etching, coating, cleaning, testing, etc.

[0091] It should be understood that the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0092] The following is a method embodiment of the present invention. For details not described in detail therein, reference may be made to the corresponding device embodiment described above.

[0093] Figure 5 The flowchart of the control method of the electrostatic chuck power supply provided by the embodiment of the present invention is shown. For the convenience of explanation, only the part related to the embodiment of the present invention is shown. The method is applied to the electrostatic chuck power supply. The electrostatic chuck power supply includes a detection module and a control module, which are described in detail as follows:

[0094] Step 501, the detection module sends a detection signal to the electrostatic chuck, collects a response signal returned by the detection signal after passing through the electrostatic chuck, and sends the response signal to the control module;

[0095] Step 502 : The control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal.

[0096] In a possible implementation, the detection signal is a sine wave signal; the detection module includes a sine wave generating circuit, a rectifier filtering circuit and a DC voltage sampling circuit;

[0097] The input end of the sine wave generating circuit is connected to the control module, and the output end is used to connect to the electrostatic chuck. The input end of the rectifier and filter circuit is used to connect to the electrostatic chuck, and the output end is connected to the input end of the DC voltage sampling circuit. The output end of the DC voltage sampling circuit is connected to the control module.

[0098] The detection module sends a detection signal to the electrostatic chuck, collects a response signal returned by the detection signal after passing through the electrostatic chuck, and sends the response signal to the control module, including:

[0099] The sine wave generating circuit sends a sine wave signal to the electrostatic chuck;

[0100] The rectifier and filter circuit rectifies and filters the response signal returned by the sine wave signal after passing through the electrostatic chuck to obtain a DC response signal;

[0101] The DC voltage sampling circuit performs DC voltage sampling on the DC response signal to obtain a DC voltage sampling value of the DC response signal and sends the sampling value to the control module.

[0102] In a possible implementation, the control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, including:

[0103] If the DC voltage sampling value of the DC response signal is within the first preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is that the wafer is present but not adsorbed;

[0104] If the DC voltage sampling value of the DC response signal is within the second preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is adsorption;

[0105] If the DC voltage sampling value of the DC response signal is within the third preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is released; wherein the first preset interval < the second preset interval < the third preset interval.

[0106] In a possible implementation, the control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, including:

[0107] Calculating the capacitance value of the electrostatic chuck based on the sine wave signal and the DC voltage sampling value;

[0108] The wafer adsorption state of the electrostatic chuck is determined based on the capacitance value of the electrostatic chuck.

[0109] In a possible implementation, the electrostatic chuck power supply further includes a power supply module;

[0110] The power supply module is used to connect with the electrostatic chuck and provide power to the electrostatic chuck.

[0111] In a possible implementation, the power supply module is connected to the control module;

[0112] After the control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, the method further includes:

[0113] The control module sends a power supply state adjustment instruction to the power supply module based on the wafer adsorption state of the electrostatic chuck to adjust the wafer adsorption state of the electrostatic chuck.

[0114] The embodiment of the present invention sends a detection signal to the electrostatic chuck, collects a response signal returned after the detection signal passes through the electrostatic chuck, compares the detection signal with the response signal, and determines the change of the detection signal after passing through the electrostatic chuck, thereby determining the wafer adsorption state of the electrostatic chuck based on the correspondence between the change of the detection signal and the clamping degree between the wafer and the electrostatic chuck.

[0115] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0116] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0117] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0118] In the embodiments provided by the present invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0119] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0120] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0121] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned control method of each electrostatic chuck power supply can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to actual conditions and requirements. For example, the computer-readable medium does not include electric carrier signals and telecommunication signals.

[0122] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. An electrostatic chuck power supply, characterized in that: It includes a detection module and a control module, wherein the detection module is connected to the control module; The detection module is used to connect with the electrostatic chuck, send a detection signal to the electrostatic chuck, collect a response signal returned by the detection signal after passing through the electrostatic chuck, and send the response signal to the control module; wherein the detection signal is a sine wave signal with an amplitude lower than a preset threshold; The control module is used to determine the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal; wherein the wafer adsorption state includes that there is a wafer on the electrostatic chuck and the power is turned on; Also includes a power supply module; The power supply module is used to connect with the electrostatic chuck and supply power to the electrostatic chuck; The power supply module is connected to the control module; The control module is further configured to send a power supply state adjustment instruction to the power supply module based on the wafer adsorption state of the electrostatic chuck, so as to adjust the wafer adsorption state of the electrostatic chuck.

2. The electrostatic chuck power supply according to claim 1, characterized in that: The detection signal is a sine wave signal; the detection module includes a sine wave generating circuit, a rectifier and filter circuit, and a DC voltage sampling circuit; The input end of the sine wave generating circuit is connected to the control module, and the output end is used to be connected to the electrostatic chuck. The input end of the rectifier and filter circuit is used to be connected to the electrostatic chuck, and the output end is connected to the input end of the DC voltage sampling circuit. The output end of the DC voltage sampling circuit is connected to the control module. The sine wave generating circuit is used to send a sine wave signal to the electrostatic chuck; The rectification and filtering circuit is used to rectify and filter the response signal returned by the sine wave signal after passing through the electrostatic chuck to obtain a DC response signal; The DC voltage sampling circuit is used to perform DC voltage sampling on the DC response signal, obtain a DC voltage sampling value of the DC response signal, and send the DC voltage sampling value to the control module.

3. The electrostatic chuck power supply according to claim 2, characterized in that: The control module is specifically used for: If the DC voltage sampling value of the DC response signal is within a first preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is that the wafer is present but not adsorbed; If the DC voltage sampling value of the DC response signal is within a second preset interval, determining that the wafer adsorption state of the electrostatic chuck is adsorption; If the DC voltage sampling value of the DC response signal is within a third preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is released; wherein the first preset interval is less than the second preset interval and less than the third preset interval.

4. The electrostatic chuck power supply according to claim 2, characterized in that: The control module is specifically used for: Calculating a capacitance value of the electrostatic chuck based on the sine wave signal and the DC voltage sampling value; A wafer adsorption state of the electrostatic chuck is determined based on a capacitance value of the electrostatic chuck.

5. A method for controlling an electrostatic chuck power supply, characterized in that: Applied to an electrostatic chuck power supply, the electrostatic chuck power supply includes a detection module and a control module; the method includes: The detection module sends a detection signal to the electrostatic chuck, collects a response signal returned by the detection signal after passing through the electrostatic chuck, and sends the response signal to the control module; wherein the detection signal is a sine wave signal with an amplitude lower than a preset threshold; The control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal; wherein the wafer adsorption state includes that there is a wafer on the electrostatic chuck and a high voltage power supply is turned on; The electrostatic chuck power supply also includes a power supply module; The power supply module is used to connect with the electrostatic chuck and supply power to the electrostatic chuck; The power supply module is connected to the control module; After the control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, the method further includes: The control module sends a power supply state adjustment instruction to the power supply module based on the wafer adsorption state of the electrostatic chuck to adjust the wafer adsorption state of the electrostatic chuck.

6. The control method of the electrostatic chuck power supply according to claim 5, characterized in that: The detection signal is a sine wave signal; the detection module includes a sine wave generating circuit, a rectifier and filter circuit, and a DC voltage sampling circuit; The input end of the sine wave generating circuit is connected to the control module, and the output end is used to be connected to the electrostatic chuck. The input end of the rectifier and filter circuit is used to be connected to the electrostatic chuck, and the output end is connected to the input end of the DC voltage sampling circuit. The output end of the DC voltage sampling circuit is connected to the control module. The detection module sends a detection signal to the electrostatic chuck, collects a response signal returned by the detection signal after passing through the electrostatic chuck, and sends the response signal to the control module, including: The sine wave generating circuit sends a sine wave signal to the electrostatic chuck; The rectification and filtering circuit rectifies and filters the response signal returned by the sine wave signal after passing through the electrostatic chuck to obtain a DC response signal; The DC voltage sampling circuit performs DC voltage sampling on the DC response signal to obtain a DC voltage sampling value of the DC response signal and sends the DC voltage sampling value to the control module.

7. The control method of the electrostatic chuck power supply according to claim 6, characterized in that: The control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, including: If the DC voltage sampling value of the DC response signal is within a first preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is that the wafer is present but not adsorbed; If the DC voltage sampling value of the DC response signal is within a second preset interval, determining that the wafer adsorption state of the electrostatic chuck is adsorption; If the DC voltage sampling value of the DC response signal is within a third preset interval, it is determined that the wafer adsorption state of the electrostatic chuck is released; wherein the first preset interval is less than the second preset interval and less than the third preset interval.

8. The control method of the electrostatic chuck power supply according to claim 6, characterized in that: The control module determines the wafer adsorption state of the electrostatic chuck based on the detection signal and the response signal, including: Calculating a capacitance value of the electrostatic chuck based on the sine wave signal and the DC voltage sampling value; A wafer adsorption state of the electrostatic chuck is determined based on a capacitance value of the electrostatic chuck.

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