Semiconductor process equipment and method for detecting stability of electrostatic chuck

Abstract

The invention discloses semiconductor process equipment and a method for detecting the stability of an electrostatic chuck. The semiconductor process equipment comprises a gas assembly, a process chamber, a direct-current power supply and a capacitance detection module, an electrostatic chuck is arranged in the process chamber, the direct-current power supply is connected with the electrostatic chuck, the direct-current power supply supplies power to the electrostatic chuck, and the electrostatic chuck adsorbs a wafer placed on the electrostatic chuck; the gas assembly is connected with a base of the electrostatic chuck, and the gas assembly is used for conveying auxiliary gas to the process chamber after the process of the semiconductor process equipment is finished and the wafer is desorbed from the electrostatic chuck; the capacitance detection module is connected between an adsorption electrode in the electrostatic chuck and the direct-current power supply, the capacitance detection module detects capacitance values between the adsorption electrode and the direct-current power supply respectively after the wafer and the electrostatic chuck are desorbed and adsorbed, and the stability of the electrostatic chuck is judged according to the capacitance values before adsorption and the capacitance values after adsorption. According to the invention, the stability of the electrostatic chuck can be judged.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of semiconductor processes, and in particular, to a semiconductor process equipment and a method for detecting the stability of an electrostatic chuck. Background Art

[0002] Plasma equipment has been widely used in the semiconductor equipment industry. In the field of semiconductor etching, it is mainly divided into inductively coupled plasma (ICP) etching and capacitively coupled plasma (CCP) etching. CCP etching generally forms a plasma by applying a high-frequency alternating current (usually 13.56 MHz) to establish an electric field between two electrodes, so as to etch the material. ICP etching is a method of generating a magnetic field in a coil through a high-frequency current and forming a plasma near the workpiece through electromagnetic induction. This technology usually uses a higher-frequency power supply (for example, 13.56 MHz or higher frequency) to excite the plasma. CCP etching transfers energy between electrodes through capacitive coupling, and the etching process is relatively mild, suitable for processes with lower damage requirements. While ICP etching transfers energy through inductive coupling, and the energy is transmitted through the magnetic field, which is more efficient and usually can obtain a higher plasma density. No matter which method is used, an electrostatic chuck (ESC) is required. An electrostatic chuck is a tool that generates an attractive force through static electricity to adsorb and fix the wafer on the surface of the chuck. Compared with traditional vacuum chucks and mechanical chucks, ESC is widely used in precision processing fields such as wafer etching due to its advantages of small damage to the wafer and high precision.

[0003] Although special attention is paid to the protection of the ESC, multiple cyclic operations may damage the stability of the ESC. For example, after repeatedly lifting the ESC in the wafer etching process, it may be difficult for the ESC to return to its initial position or even rub against the underlying wiring and be damaged. Then, the monitoring of the ESC after each wafer loading and unloading operation will directly affect the process processing effect of the wafer. Currently, existing semiconductor process equipment cannot determine the stability of the electrostatic chuck. Summary of the Invention

[0004] The present invention provides a semiconductor process equipment and a method for detecting the stability of an electrostatic chuck, which can determine the stability of the electrostatic chuck.

[0005] According to one aspect of the present invention, a semiconductor process equipment is provided. The semiconductor process equipment includes: a gas assembly, a process chamber, a DC power supply, and a capacitance detection module;

[0006] An electrostatic chuck is disposed in the process chamber. The DC power supply is connected to the electrostatic chuck. The DC power supply is used to supply power to the electrostatic chuck, and the electrostatic chuck is used to adsorb a wafer placed thereon.

[0007] The gas assembly is connected to the base of the electrostatic chuck. After the semiconductor process equipment finishes the process and the wafer is desorbed from the electrostatic chuck, the gas assembly is used to convey auxiliary gas to the process chamber.

[0008] The capacitance detection module is connected between the adsorption electrode in the electrostatic chuck and the DC power supply. After the wafer is desorbed from and adsorbed to the electrostatic chuck, the capacitance detection module is used to detect the capacitance value between the adsorption electrode and the DC power supply respectively, and judge the stability of the electrostatic chuck according to the capacitance values before and after adsorption.

[0009] Optionally, the capacitance detection module includes: a first capacitance detector and a second capacitance detector, and the adsorption electrode includes: a first adsorption electrode and a second adsorption electrode.

[0010] The first capacitance detector is connected between the first adsorption electrode and the DC power supply. After the wafer is desorbed from and adsorbed to the electrostatic chuck, the first capacitance detector is used to detect the capacitance value between the first adsorption electrode and the DC power supply respectively, and judge the stability of the electrostatic chuck according to the capacitance values before and after adsorption.

[0011] The second capacitance detector is connected between the second adsorption electrode and the DC power supply. After the wafer is desorbed from and adsorbed to the electrostatic chuck, the second capacitance detector is used to detect the capacitance value between the second adsorption electrode and the DC power supply respectively, and judge the stability of the electrostatic chuck according to the capacitance values before and after adsorption.

[0012] Optionally, the semiconductor process equipment further includes: a first DC filter and a second DC filter.

[0013] The first DC filter is connected between the first adsorption electrode and the first capacitance detector, and the second DC filter is connected between the second adsorption electrode and the second capacitance detector.

[0014] Optionally, the first DC filter includes a first resistor and a first capacitor. The first end of the first resistor is connected to the first adsorption electrode and the first capacitance detector, the second end of the first resistor is connected to the first end of the first capacitor, and the second end of the first capacitor is grounded.

[0015] The second DC filter includes a second resistor and a second capacitor. The first end of the second resistor is connected to the second adsorption electrode and the second capacitor detector. The second end of the second resistor is connected to the first end of the second capacitor, and the second end of the second capacitor is grounded.

[0016] According to another aspect of the present invention, there is provided a method for detecting the stability of an electrostatic chuck. The method for detecting the stability of the electrostatic chuck is applied to the semiconductor process equipment according to any embodiment of the present invention. The detection method includes:

[0017] After the process in the semiconductor process equipment is completed and the wafer is desorbed from the electrostatic chuck, an auxiliary gas is supplied to the process chamber.

[0018] After the wafer is desorbed from and adsorbed onto the electrostatic chuck, the capacitance values between the adsorption electrode and the DC power supply are respectively detected, and the stability of the electrostatic chuck is judged based on the capacitance values before and after adsorption.

[0019] Optionally, the step of respectively detecting the capacitance values between the adsorption electrode and the DC power supply after the wafer is desorbed from and adsorbed onto the electrostatic chuck, and judging the stability of the electrostatic chuck based on the capacitance values before and after adsorption includes:

[0020] After the wafer is desorbed from and adsorbed onto the electrostatic chuck, the capacitance values between the first adsorption electrode and the DC power supply are respectively detected, and the stability of the electrostatic chuck is judged based on the capacitance values before and after adsorption.

[0021] After the wafer is desorbed from and adsorbed onto the electrostatic chuck, the capacitance values between the second adsorption electrode and the DC power supply are respectively detected, and the stability of the electrostatic chuck is judged based on the capacitance values before and after adsorption.

[0022] Optionally, after the process in the semiconductor process equipment is completed, after the wafer is desorbed from the electrostatic chuck, and after the auxiliary gas is supplied to the process chamber, the method further includes:

[0023] After the wafer is desorbed from or adsorbed onto the electrostatic chuck, the first capacitance value between the first adsorption electrode and the DC power supply and the second capacitance value between the second adsorption electrode and the DC power supply are respectively detected, and the abnormal state of the electrostatic chuck is judged based on the first capacitance value and the second capacitance value.

[0024] Optionally, the step of judging the abnormal state of the electrostatic chuck based on the first capacitance value and the second capacitance value includes:

[0025] When the first capacitance value and the second capacitance value are not equal and the difference is within the range of a first preset value, ions are attached to the bottom of the electrostatic chuck;

[0026] When the first capacitance value and the second capacitance value are not equal and the difference is within the range of a second preset value, there is an obstacle between the electrostatic chuck and the wafer;

[0027] When the first capacitance value is much greater than the second capacitance value or the second capacitance value is much greater than the first capacitance value, the line between the electrostatic chuck and the DC power supply falls off.

[0028] According to another aspect of the present invention, there is also provided an electronic device, which includes:

[0029] One or more processors;

[0030] A memory for storing one or more programs;

[0031] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for detecting the stability of the electrostatic chuck as described in any embodiment of the present invention.

[0032] According to another aspect of the present invention, there is also provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the method for detecting the stability of the electrostatic chuck as described in any embodiment of the present invention is implemented.

[0033] In the technical solution of the embodiment of the present invention, after the semiconductor process equipment finishes the process treatment of the wafer, after the wafer is desorbed from the electrostatic chuck, an auxiliary gas is introduced into the process chamber, the capacitance detection module at the connection between the DC power supply and the electrostatic chuck is monitored and observed in real time to detect the reading of the capacitance value, the wafer to be etched is placed and adsorbed, and the reading of the capacitance value detected by the capacitance detection module is observed again; the stability of the electrostatic chuck is judged according to the capacitance values before and after adsorption, and the semiconductor process equipment realizes the judgment of the stability of the electrostatic chuck in the process chamber, ensuring the stable function of the electrostatic chuck in each wafer etching process. In summary, the present invention solves the problem that the existing semiconductor process equipment cannot judge the stability of the electrostatic chuck.

[0034] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0036] Figure 1 is a schematic structural diagram of a semiconductor process equipment provided according to an embodiment of the present invention;

[0037] Figure 2 is a schematic structural diagram of another semiconductor process equipment provided according to an embodiment of the present invention;

[0038] Figure 3 is a schematic diagram when an abnormal situation occurs in the first electrostatic chuck provided according to an embodiment of the present invention;

[0039] Figure 4 is a schematic diagram when an abnormal situation occurs in the second electrostatic chuck provided according to an embodiment of the present invention;

[0040] Figure 5 is a schematic diagram when an abnormal situation occurs in the third electrostatic chuck provided according to an embodiment of the present invention;

[0041] Figure 6 is a schematic diagram of the working principle of a DC power supply provided according to an embodiment of the present invention;

[0042] Figure 7 is a schematic structural diagram of another semiconductor process equipment provided according to an embodiment of the present invention;

[0043] Figure 8 is a flowchart of a method for detecting the stability of an electrostatic chuck provided according to an embodiment of the present invention;

[0044] Figure 9 is a schematic structural diagram of an electronic device provided according to an embodiment of the present invention. Detailed Embodiments

[0045] To enable those skilled in the art to better understand the solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0046] It should be noted that the terms "first", "second", etc. in the description, claims and the above drawings of the present invention are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data used can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0047] Figure 1 is a schematic structural diagram of a semiconductor process equipment provided according to an embodiment of the present invention. Referring to Figure 1 , an embodiment of the present invention provides a semiconductor process equipment, which includes: a gas assembly 10, a process chamber 20, a DC power supply 40, and a capacitance detection module 50;

[0048] An electrostatic chuck 30 is disposed in the process chamber 20. The DC power supply 40 is connected to the electrostatic chuck 30. The DC power supply 40 is used to supply power to the electrostatic chuck 30, and the electrostatic chuck 30 is used to adsorb the wafer placed on the electrostatic chuck 30.

[0049] The gas assembly 10 is connected to the base of the electrostatic chuck 30. The gas assembly 10 is used to supply auxiliary gas to the process chamber 20 after the process of the semiconductor process equipment ends and after the wafer is desorbed from the electrostatic chuck 30.

[0050] The capacitance detection module 50 is connected between the adsorption electrode 31 in the electrostatic chuck 30 and the DC power supply 40. The capacitance detection module 50 is used to detect the capacitance value between the adsorption electrode 31 and the DC power supply 40 respectively after the wafer is desorbed from and adsorbed onto the electrostatic chuck 30, and to judge the stability of the electrostatic chuck 30 according to the capacitance value before adsorption and the capacitance value after adsorption.

[0051] Specifically, the process chamber 20 is grounded. An electrostatic chuck 30 is disposed in the process chamber 20. The electrostatic chuck 30 is embedded with an adsorption electrode 31, and a wafer is adsorbed on the surface of the electrostatic chuck 30. When the semiconductor process equipment processes the wafer, the DC power supply 40 is used to provide a DC high voltage (HV) for the electrostatic chuck 30. Under the action of the DC high voltage, the electrostatic chuck 30 generates an adsorption effect on the wafer placed on its surface.

[0052] When performing process steps such as etching on a wafer, the wafer is placed on the electrostatic chuck 30 inside the process chamber 20. Then, an adsorption voltage is applied to the adsorption electrode 31 inside the electrostatic chuck 30 through a DC power supply 40, so as to adsorb and fix the wafer on the electrostatic chuck 30 through the electrostatic adsorption force on the electrostatic chuck 30. Then, processing technologies such as etching are performed on the wafer. After the processes such as etching are completed, the application of the adsorption voltage to the adsorption electrode 31 of the electrostatic chuck 30 is stopped, and a reverse voltage opposite to the adsorption voltage is applied to the adsorption electrode 31 of the electrostatic chuck 30 to eliminate the electrostatic adsorption force on the electrostatic chuck 30, so that the wafer is desorbed from the electrostatic chuck 30, and the wafer is removed from the process chamber 20. After the next wafer is moved into the process chamber 20, steps such as adsorbing and fixing it on the electrostatic chuck 30 are repeated, and the next wafer is processed.

[0053] After the semiconductor process equipment finishes processing the wafer, after desorbing the wafer from the electrostatic chuck 30, an auxiliary gas is introduced into the process chamber 20 to maintain the uniformity and stability of the process chamber 20. The capacitance detection module 50 at the connection between the DC power supply 40 and the electrostatic chuck 30 is observed, and the reading of the capacitance value detected by the capacitance detection module 50 is monitored and observed in real time. The wafer to be etched is placed and adsorbed, and the reading of the capacitance value detected by the capacitance detection module 50 is observed again. Under stable conditions of the capacitance detection module 50, the readings of the capacitance values before and after adsorption should be basically unchanged. The stability of the electrostatic chuck 30 is judged according to the readings of the capacitance values before and after adsorption, and the semiconductor process equipment realizes the determination of the stability of the electrostatic chuck 30 in the process chamber 20.

[0054] Optionally, the range of the capacitance value before adsorption includes 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption includes 4.5 nF ± 0.5 nF. Exemplarily, the capacitance detection module 50 is under the conditions of a pressure of 200 mTorr and 200 sccm O 2 Under the conditions, the range of the capacitance value before adsorption can be 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption can be 4.5 nF ± 0.5 nF, indicating that the stability of the electrostatic chuck 30 meets the requirements, and the consistency and stability of the electrostatic chuck 30 in the front and back processing can be determined.

[0055] For example, a significant increase in the reading of the capacitance detection module 50 may be caused by the downward movement of the position of the electrostatic chuck 30 or the accumulation of ions on the lower surface of the electrostatic chuck 30. According to the capacitance value detected by the capacitance detection module 50, it can be determined whether the next wafer process can be continued. The problem in what situation can be judged according to the abnormal fluctuation of the capacitance detection value, and then solved specifically.

[0056] In the technical solution of the embodiment of the present invention, after the semiconductor process equipment finishes the process treatment of the wafer, after desorbing the wafer from the electrostatic chuck, auxiliary gas is introduced into the process chamber, and the capacitance detection module at the connection between the DC power supply and the electrostatic chuck is monitored and observed in real time to detect the reading of the capacitance value. Then, the wafer to be etched is placed and adsorbed, and the reading of the capacitance value detected by the capacitance detection module is observed again; the stability of the electrostatic chuck is judged according to the capacitance values before and after adsorption. The semiconductor process equipment realizes the determination of the stability of the electrostatic chuck in the process chamber, ensuring the stable function of the electrostatic chuck in each wafer etching process. In summary, the present invention solves the problem that the existing semiconductor process equipment cannot determine the stability of the electrostatic chuck.

[0057] Figure 2 is a schematic structural diagram of another semiconductor process equipment provided according to an embodiment of the present invention. Refer to Figure 2 , optionally, the capacitance detection module 50 includes: a first capacitance detector 51 and a second capacitance detector 52, and the adsorption electrode 31 includes: a first adsorption electrode 301 and a second adsorption electrode 302;

[0058] The first capacitance detector 51 is connected between the first adsorption electrode 301 and the DC power supply 40. The first capacitance detector 51 is used to detect the capacitance value between the first adsorption electrode 301 and the DC power supply 40 respectively after the wafer is desorbed from and adsorbed to the electrostatic chuck 30, and judge the stability of the electrostatic chuck 30 according to the capacitance values before and after adsorption;

[0059] The second capacitance detector 52 is connected between the second adsorption electrode 302 and the DC power supply 40. The second capacitance detector 52 is used to detect the capacitance value between the second adsorption electrode 302 and the DC power supply 40 respectively after the wafer is desorbed from and adsorbed to the electrostatic chuck 30, and judge the stability of the electrostatic chuck 30 according to the capacitance values before and after adsorption.

[0060] Specifically, the first adsorption electrode 301 can be a positive electrode, and the second adsorption electrode 302 can be a negative electrode. By applying appropriate voltages to the positive electrode and the negative electrode, the balance of the adsorption forces of the positive electrode and the negative electrode on the wafer is ensured. The first capacitance detector 51 can be a positive capacitance detector, and the second capacitance detector 52 can be a negative capacitance detector.

[0061] After the semiconductor processing equipment finishes processing the wafer, after desorbing the wafer from the electrostatic chuck 30 and introducing an auxiliary gas into the process chamber 20 to maintain the uniformity and stability of the process chamber 20, observe the first capacitance detector 51 and the second capacitance detector 52 at the connection between the DC power supply 40 and the first adsorption electrode 301 and the second adsorption electrode 302, and monitor and observe in real time the readings of the capacitance values detected by the first capacitance detector 51 and the second capacitance detector 52. Place the wafer to be etched and perform adsorption, and then observe again the readings of the capacitance values detected by the first capacitance detector 51 and the second capacitance detector 52. When the first capacitance detector 51 and the second capacitance detector 52 are in a stable state, the readings of the capacitance values before adsorption and after adsorption should be basically unchanged. Determine the stability of the electrostatic chuck 30 based on the readings of the capacitance values before adsorption and after adsorption. This semiconductor processing equipment realizes the determination of the stability of the electrostatic chuck 30 in the process chamber 20.

[0062] Exemplarily, when the pressure is 200 mTorr and 200 sccm O 2 condition, the range of the capacitance value before adsorption can be 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption can be 4.5 nF ± 0.5 nF, indicating that the stability of the electrostatic chuck 30 meets the requirements, and the consistency and stability of the electrostatic chuck 30 before and after processing can be determined.

[0063] After each process ends, the cleaning step cannot completely remove the residual charge and the inconsistency of the capacitance detector, resulting in a slight difference between the two capacitance detectors, which belongs to the normal range. For example, when the capacitance values detected by the positive capacitance detector and the negative capacitance detector are 3.4 nF and 3.5 nF respectively, it is within the normal range. It should be noted that the difference between the capacitance values detected by the two capacitance detectors within 0.2 nF belongs to the acceptable range.

[0064] Optionally, the calculation formulas for the capacitance values before adsorption and after adsorption are as follows:

[0065]

[0066] Where C is the capacitance value, ε is the dielectric constant, A is the common area between the wafer and the electrostatic chuck, and d is the distance between the wafer and the electrostatic chuck.

[0067] Specifically, the capacitance value can be calculated based on the common area, distance, and dielectric constant of the electrostatic chuck material between the electrostatic chuck and the wafer.

[0068] When the capacitance values detected by the first capacitance detector and the second capacitance detector are abnormal, the possible abnormal situations are as follows:

[0069] Figure 3 is a schematic diagram when an abnormality occurs in the first electrostatic chuck provided according to an embodiment of the present invention. Refer to Figure 3 , Figure 3 which shows a situation where the process chamber is not sufficiently cleaned and ions are attached to the chassis of the electrostatic chuck. The charge amount of the electrostatic chuck changes, causing the capacitance value to change. There is a slight difference in the capacitance values detected by the first capacitance detector and the second capacitance detector. A normal value within 0.2 nF is within the acceptable range.

[0070] Figure 4 is a schematic diagram when an abnormality occurs in the second electrostatic chuck provided according to an embodiment of the present invention. Refer to Figure 4 , Figure 4 which shows a situation where the wafer is not placed horizontally or there are small obstacles between the wafer and the electrostatic chuck. The fact that the wafer is not placed horizontally or there are small obstacles between the wafer and the electrostatic chuck causes a slight difference in the values of the two capacitance detectors.

[0071] Figure 5 is a schematic diagram when an abnormality occurs in the third electrostatic chuck provided according to an embodiment of the present invention. Refer to Figure 5 , Figure 5 which shows a situation where the line between the electrostatic chuck and the DC power supply falls off. The reading of one capacitance detector is much larger than that of the other capacitance detector. For example, one reading is in the nF level and the other is in the uF level. It may be caused by the line between the electrostatic chuck and the DC power supply falling off.

[0072] The semiconductor process equipment is under the conditions of a pressure of 200 mTorr and 200 sccmO 2 The range of the capacitance value before adsorption can be 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption can be 4.5 nF ± 0.5 nF. Similarly, it is applicable to all types of machines. If the detected value of the data recorded during the operation of the first capacitance detector and the second capacitance detector exceeds 10 nF at any moment, the process chamber should be immediately opened for processing.

[0073] Figure 6 is a schematic diagram of the working principle of a DC power supply provided according to an embodiment of the present invention. Refer to Figure 6 The HV positive and negative poles of the DC power supply are independently separated. Figure 6 which shows the path of a closed-loop circuit. Starting from the positive power supply, passing through the positive electrode plate, the negative electrode plate, and finally to the inner wall of the process chamber, and the process chamber is grounded.

[0074] When processing a wafer, after a DC power supply generates a DC high voltage, it is connected to the adsorption electrode in the electrostatic chuck through a capacitance detection module, making the adsorption electrode charged, thereby generating an adsorption effect on the wafer. Under the excitation of the RF coil in the process chamber, an RF plasma is generated in the process chamber. After the process is completed, the plasma in the process chamber is continuously maintained through the gas assembly in the semiconductor process equipment, so that the process chamber is continuously in an RF environment, which enables an electrical connection between the upper surface of the electrostatic chuck and the process chamber through the plasma. Since the process chamber is grounded, at this time, the upper surface of the electrostatic chuck is equivalent to being grounded.

[0075] Due to the existence of the negative bias voltage, when the semiconductor process equipment uses the pulse function, the alternating negative bias voltage may instantaneously reach more than 2 kV, resulting in an excessive voltage inside the process chamber to form an arc. And it leaves black marks at the bottom of the electrostatic chuck or breaks through the electrostatic chuck to form cracks. At the same time, it will also change the normal impedance environment of the chamber, the matcher exceeds the impedance matching range and affects the normal use of the process.

[0076] Figure 7 It is a schematic structural diagram of another semiconductor process equipment according to an embodiment of the present invention. Refer to Figure 7 , optionally, the semiconductor process equipment further includes: a first DC filter 60 and a second DC filter 70;

[0077] The first DC filter 60 is connected between the first adsorption electrode 301 and the first capacitance detector 51, and the second DC filter 70 is connected between the second adsorption electrode 302 and the second capacitance detector 52.

[0078] Specifically, the first DC filter 60 and the second DC filter 70 are actually equivalent to an RF filter, which filters out RF signals through this RF filter, avoiding the leakage of the RF environment in the process chamber 20 and causing influence or damage to the human body and other equipment (such as the DC power supply 40 and the capacitance detection module 50, etc.).

[0079] Continue to refer to Figure 7 , optionally, the first DC filter 60 includes a first resistor R1 and a first capacitor C1. The first end of the first resistor R1 is connected to the first adsorption electrode 301 and the first capacitance detector 51, the second end of the first resistor R1 is connected to the first end of the first capacitor C1, and the second end of the first capacitor C1 is grounded;

[0080] The second DC filter 70 includes a second resistor R2 and a second capacitor C2. The first end of the second resistor R2 is connected to the second adsorption electrode 302 and the second capacitance detector 52, the second end of the second resistor R2 is connected to the first end of the second capacitor C2, and the second end of the second capacitor C2 is grounded.

[0081] Specifically, the first resistor R1 and the first capacitor C1 form a first RC filter circuit, and the second resistor R2 and the second capacitor C2 form a second RC filter circuit. The RC filter circuit filters out high-frequency components in the input signal through the charging and discharging characteristics of the capacitor and outputs a relatively stable DC signal. Different filtering effects can be achieved by adjusting the values of the resistor and the capacitor.

[0082] Figure 8 is a flowchart of a method for detecting the stability of an electrostatic chuck according to an embodiment of the present invention. Refer to Figure 8 Moreover, an embodiment of the present invention also provides a method for detecting the stability of an electrostatic chuck. The method for detecting the stability of the electrostatic chuck is applied to the semiconductor process equipment according to any embodiment of the present invention. The detection method includes:

[0083] S110. After the semiconductor process equipment finishes the process and the wafer is desorbed from the electrostatic chuck, an auxiliary gas is introduced into the process chamber.

[0084] Specifically, in combination with Figure 1 , after the semiconductor process equipment finishes processing the wafer and after the wafer is desorbed from the electrostatic chuck 30, an auxiliary gas is introduced into the process chamber 20 to maintain the uniformity and stability of the process chamber 20.

[0085] S120. After the wafer is desorbed from and adsorbed to the electrostatic chuck, the capacitance values between the adsorption electrode and the DC power supply are respectively detected, and the stability of the electrostatic chuck is judged according to the capacitance values before and after adsorption.

[0086] Specifically, in combination with Figure 1 , the capacitance detection module 50 at the connection between the DC power supply 40 and the electrostatic chuck 30 is observed, the readings of the capacitance values detected by the capacitance detection module 50 are monitored and observed in real time. The wafer to be etched is placed and adsorbed, and then the readings of the capacitance values detected by the capacitance detection module 50 are observed again. Under stable conditions, the readings of the capacitance values before and after adsorption by the capacitance detection module 50 should be basically unchanged. The stability of the electrostatic chuck 30 is judged according to the readings of the capacitance values before and after adsorption, and the semiconductor process equipment realizes the determination of the stability of the electrostatic chuck 30 in the process chamber 20.

[0087] Exemplarily, under the conditions of a pressure of 200 mTorr and 200 sccm O 2 , the range of the capacitance value before adsorption can be 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption can be 4.5 nF ± 0.5 nF, indicating that the stability of the electrostatic chuck 30 meets the requirements, and the consistency and stability of the electrostatic chuck 30 before and after processing can be determined.

[0088] The detection method for the stability of the electrostatic chuck provided by the embodiment of the present invention is used to control the semiconductor process equipment provided by the embodiment of the present invention. Therefore, the above detection method for the stability of the electrostatic chuck has the same beneficial effects as the semiconductor process equipment, and will not be elaborated here.

[0089] Based on the above embodiments, the embodiment of the present invention further refines step S120, which will be specifically described below, but it is not a limitation to the present invention.

[0090] S120: After the wafer is desorbed from and adsorbed to the electrostatic chuck, respectively detect the capacitance value between the adsorption electrode and the DC power supply, and judge the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption, including:

[0091] After the wafer is desorbed from and adsorbed to the electrostatic chuck, respectively detect the capacitance value between the first adsorption electrode and the DC power supply, and judge the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption

[0092] After the wafer is desorbed from and adsorbed to the electrostatic chuck, respectively detect the capacitance value between the second adsorption electrode and the DC power supply, and judge the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption.

[0093] Specifically, in combination with Figure 2 , observe the first capacitance detector 51 and the second capacitance detector 52 at the connection of the DC power supply 40 and the first adsorption electrode 301 and the second adsorption electrode 302, and real-time monitor and observe the readings of the capacitance values detected by the first capacitance detector 51 and the second capacitance detector 52. Place the wafer to be etched and perform adsorption, and then observe the readings of the capacitance values detected by the first capacitance detector 51 and the second capacitance detector 52 again. When the first capacitance detector 51 and the second capacitance detector 52 are in a stable state, the readings of the capacitance values before adsorption and after adsorption should be basically unchanged. Judge the stability of the electrostatic chuck 30 according to the readings of the capacitance values before adsorption and after adsorption. This semiconductor process equipment realizes the determination of the stability of the electrostatic chuck 30 in the process chamber 20.

[0094] Exemplarily, when the pressure is 200 mTorr and 200 sccmO 2 Under the conditions, the range of the capacitance value before adsorption can be 3.5 nF ± 0.5 nF, and the range of the capacitance value after adsorption can be 4.5 nF ± 0.5 nF, indicating that the stability of the electrostatic chuck 30 meets the requirements, and the consistency and stability of the electrostatic chuck 30 before and after processing can be determined.

[0095] In addition to detecting whether the electrostatic chuck is stable, the semiconductor process equipment can also determine what kind of abnormality exists in the electrostatic chuck based on the detected capacitance value.

[0096] Optionally, after the semiconductor process equipment finishes the process, after the wafer is desorbed from the electrostatic chuck, and after an auxiliary gas is delivered to the process chamber, it further includes:

[0097] After the wafer is desorbed from or adsorbed to the electrostatic chuck, the first capacitance value between the first adsorption electrode and the DC power supply and the second capacitance value between the second adsorption electrode and the DC power supply are respectively detected, and the abnormal state of the electrostatic chuck is judged according to the first capacitance value and the second capacitance value.

[0098] Optionally, judging the abnormal state of the electrostatic chuck according to the first capacitance value and the second capacitance value includes:

[0099] If the first capacitance value and the second capacitance value are not equal and the difference is within the range of the first preset value, then ions are attached to the bottom of the electrostatic chuck;

[0100] If the first capacitance value and the second capacitance value are not equal and the difference is within the range of the second preset value, then there is an obstacle between the electrostatic chuck and the wafer;

[0101] If the first capacitance value is much larger than the second capacitance value or the second capacitance value is much larger than the first capacitance value, then the line between the electrostatic chuck and the DC power supply is disconnected.

[0102] Specifically, in combination with Figure 3 , Figure 3 shows a situation where the bottom plate of the electrostatic chuck is attached with ions due to insufficient cleaning of the process chamber. The charge amount of the electrostatic chuck changes, resulting in a change in the capacitance value. There is a small difference in the capacitance values detected by the first capacitance detector and the second capacitance detector. A difference within 0.2 nF is within the acceptable range under normal circumstances.

[0103] In combination with Figure 4 , Figure 4 shows a situation where the wafer is not placed horizontally or there are small obstacles between the wafer and the electrostatic chuck. When the wafer is not placed horizontally or there are small obstacles between the wafer and the electrostatic chuck, there will be a slight difference in the values of the two capacitance detectors.

[0104] In combination with Figure 5 , Figure 5 shows a situation where the line between the electrostatic chuck and the DC power supply is disconnected. The reading of one capacitance detector is much larger than that of the other capacitance detector. For example, if one reading is in the nF level and the other is in the uF level, it may be caused by the disconnection of the line between the electrostatic chuck and the DC power supply.

[0105] Figure 9The schematic structural diagram of the electronic device 1 that can be used to implement the embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0106] As Figure 9 shown, the electronic device 1 includes at least one processor 11, and a memory communicatively connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc. The memory stores a computer program executable by the at least one processor. The processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 1 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. The input / output (I / O) interface 15 is also connected to the bus 14.

[0107] A plurality of components in the electronic device 1 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, an optical disc, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 1 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0108] The processor 11 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the processor 11 include but are not limited to a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, for example, the method for detecting the stability of the electrostatic chuck.

[0109] In some embodiments, the method for detecting the stability of an electrostatic chuck can be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 1 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the method for detecting the stability of the electrostatic chuck described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to perform the method for detecting the stability of the electrostatic chuck by any other suitable means (e.g., by means of firmware).

[0110] The various embodiments of the systems and techniques described above in this document can be implemented in digital electronic circuitry, integrated circuit systems, field-programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), application-specific standard products (ASSP), systems-on-a-chip (SOC), complex programmable logic devices (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a dedicated or general-purpose programmable processor that receives data and instructions from a storage system, at least one input device, and at least one output device, and transmits the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0111] The computer program for implementing the method of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a dedicated computer, or other programmable data processing device, such that when the computer programs are executed by the processor, the functions / operations specified in the flowchart and / or block diagram are implemented. The computer programs can be executed entirely on the machine, partially on the machine, as a stand-alone software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0112] In the context of the present invention, a computer-readable storage medium can be a tangible medium that can contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable storage medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, the computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0113] In order to provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0114] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer having a graphical user interface or a web browser through which the user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected to each other by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local area network (LAN), wide area network (WAN), blockchain network, and the Internet.

[0115] A computing system may include a client and a server. The client and the server are generally far from each other and usually interact via a communication network. The client-server relationship is created by computer programs running on respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or a cloud host, which is a host product in the cloud computing service system, solving the defects of difficult management and weak business scalability existing in traditional physical hosts and VPS services.

[0116] It should be understood that various forms of processes shown above can be used, with steps reordered, added or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is made herein.

[0117] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A semiconductor process equipment, characterized in that: include: Gas components, process chambers, DC power supplies, and capacitance detection modules; An electrostatic chuck is arranged in the process chamber, the DC power supply is connected to the electrostatic chuck, the DC power supply is used to supply power to the electrostatic chuck, and the electrostatic chuck is used to adsorb the wafer placed on the electrostatic chuck; The gas assembly is connected to the base of the electrostatic chuck, and the gas assembly is used to deliver auxiliary gas to the process chamber after the semiconductor process equipment is finished and the wafer is desorbed from the electrostatic chuck; The capacitance detection module is connected between the adsorption electrode in the electrostatic chuck and the DC power supply. The capacitance detection module is used to detect the capacitance value between the adsorption electrode and the DC power supply after the wafer is desorbed and adsorbed from the electrostatic chuck, respectively, and judge the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption.

2. The semiconductor process equipment according to claim 1, characterized in that: The capacitance detection module includes: a first capacitance detector and a second capacitance detector, and the adsorption electrode includes: a first adsorption electrode and a second adsorption electrode; The first capacitance detector is connected between the first adsorption electrode and the DC power supply, and is used to detect the capacitance value between the first adsorption electrode and the DC power supply after the wafer is desorbed and adsorbed from the electrostatic chuck, respectively, and judge the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption; The second capacitance detector is connected between the second adsorption electrode and the DC power supply. The second capacitance detector is used to detect the capacitance value between the second adsorption electrode and the DC power supply after the wafer is desorbed and adsorbed from the electrostatic chuck, respectively, and judge the stability of the electrostatic chuck based on the capacitance value before adsorption and the capacitance value after adsorption.

3. The semiconductor process equipment according to claim 2, characterized in that: Also includes: a first DC filter and a second DC filter; The first DC filter is connected between the first adsorption electrode and the first capacitance detector, and the second DC filter is connected between the second adsorption electrode and the second capacitance detector.

4. The semiconductor process equipment according to claim 3, characterized in that: The first DC filter includes a first resistor and a first capacitor, wherein a first end of the first resistor is connected to the first adsorption electrode and the first capacitance detector, a second end of the first resistor is connected to a first end of the first capacitor, and a second end of the first capacitor is grounded; The second DC filter includes a second resistor and a second capacitor, a first end of the second resistor is connected to the second adsorption electrode and the second capacitance detector, a second end of the second resistor is connected to the first end of the second capacitor, and a second end of the second capacitor is grounded.

5. A method for detecting the stability of an electrostatic chuck, characterized in that: Applied to the semiconductor process equipment according to any one of claims 1 to 4, the detection method comprises: After the semiconductor process equipment has finished a process and the wafer is desorbed from the electrostatic chuck, an auxiliary gas is delivered to the process chamber; After the wafer is desorbed and adsorbed from the electrostatic chuck, the capacitance value between the adsorption electrode and the DC power supply is detected respectively, and the stability of the electrostatic chuck is determined according to the capacitance value before adsorption and the capacitance value after adsorption.

6. The method according to claim 5, characterized in that After the wafer is desorbed from the electrostatic chuck and after it is adsorbed, the capacitance value between the adsorption electrode and the DC power supply is detected respectively, and the stability of the electrostatic chuck is judged according to the capacitance value before adsorption and the capacitance value after adsorption, including: After the wafer is desorbed from the electrostatic chuck and after being adsorbed from the electrostatic chuck, respectively detecting the capacitance value between the first adsorption electrode and the DC power supply, and judging the stability of the electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption; After the wafer is desorbed and adsorbed from the electrostatic chuck, the capacitance value between the second adsorption electrode and the DC power supply is detected respectively, and the stability of the electrostatic chuck is determined according to the capacitance value before adsorption and the capacitance value after adsorption.

7. The method according to claim 5, characterized in that The semiconductor process equipment further comprises: after the process is completed, the wafer is desorbed from the electrostatic chuck, and the auxiliary gas is delivered to the process chamber; After the wafer is desorbed or adsorbed from the electrostatic chuck, a first capacitance value between the first adsorption electrode and the DC power supply and a second capacitance value between the second adsorption electrode and the DC power supply are detected respectively, and an abnormal state of the electrostatic chuck is judged based on the first capacitance value and the second capacitance value.

8. The method according to claim 7, characterized in that The determining the abnormal state of the electrostatic chuck according to the first capacitance value and the second capacitance value includes: If the first capacitance value and the second capacitance value are not equal and the difference is within a first preset value range, then the bottom of the electrostatic chuck is accompanied by ions; If the first capacitance value and the second capacitance value are not equal and the difference is within a second preset value range, there is an obstacle between the electrostatic chuck and the wafer; If the first capacitance value is much larger than the second capacitance value or the second capacitance value is much larger than the first capacitance value, the line between the electrostatic chuck and the DC power supply is disconnected.

9. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method for detecting the stability of the electrostatic chuck as described in claims 5-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for detecting the stability of an electrostatic chuck as described in claims 5-8 is implemented.

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