A semiconductor process apparatus and a method for detecting stability of an electrostatic chuck

Abstract

The application discloses a kind of semiconductor process equipment and electrostatic chuck stability detection method.The semiconductor process equipment includes: gas assembly, process chamber, direct current power supply and capacitance detection module;Process chamber is provided with electrostatic chuck, direct current power supply is connected with electrostatic chuck, direct current power supply powers electrostatic chuck, and electrostatic chuck adsorbs wafer placed on electrostatic chuck;Gas assembly is connected with the base of electrostatic chuck, and gas assembly is used to transport auxiliary gas to process chamber after semiconductor process equipment in process ends, and wafer and electrostatic chuck desorption after adsorption;Capacitance detection module is connected between adsorption electrode in electrostatic chuck and direct current power supply, and capacitance detection module detects the capacitance value between adsorption electrode and direct current power supply after wafer and electrostatic chuck desorption after adsorption, and judges the stability of electrostatic chuck according to the capacitance value before adsorption and the capacitance value after adsorption.The application can determine the stability of electrostatic chuck.

Description

Technical Field

[0001] This invention relates to the field of semiconductor process technology, and in particular to a method for detecting the stability of semiconductor process equipment and electrostatic chucks. Background Technology

[0002] Plasma equipment is widely used in the semiconductor industry. In semiconductor etching, it is mainly divided into inductively coupled plasma (ICP) etching and capacitively coupled plasma (CCP) etching. CCP etching typically uses a high-frequency alternating current (usually 13.56 MHz) to create an electric field between two electrodes, forming plasma to etch the material. ICP etching uses a high-frequency current to generate a magnetic field in a coil, forming plasma near the workpiece through electromagnetic induction. This technique usually uses a higher frequency power supply (e.g., 13.56 MHz or higher) to excite the plasma. CCP etching transfers energy between electrodes via capacitive coupling, resulting in a relatively gentle etching process suitable for processes requiring low damage. ICP etching, on the other hand, uses inductive coupling, transferring energy through a magnetic field, making it more efficient and typically achieving higher plasma densities. Both methods require an electrostatic chuck (ESC), a tool that uses electrostatic attraction to hold the wafer in place on its surface. Compared to traditional vacuum chucks and mechanical chucks, ESCs are widely used in precision machining fields such as wafer etching due to their advantages of less damage to wafers and higher precision.

[0003] While special attention is paid to protecting the ESC (Electrostatic Discharge Chrominator), repeated cycles can damage its stability. For example, during wafer etching, repeated lifting of the ESC can cause it to struggle to return to its initial position or even rub against and damage the underlying wiring. Therefore, monitoring the ESC after each wafer loading and unloading operation directly impacts the wafer processing results. Currently, existing semiconductor process equipment cannot determine the stability of the electrostatic chuck. Summary of the Invention

[0004] This invention provides a method for detecting the stability of semiconductor process equipment and electrostatic chucks, which can determine the stability of electrostatic chucks.

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

[0006] An electrostatic chuck is provided in the process chamber. The DC power supply is connected to the electrostatic chuck. The DC power supply is used to power the electrostatic chuck. The electrostatic chuck is used to adsorb the wafers placed on the electrostatic chuck.

[0007] 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 has completed the process and the wafer has desorbed from the electrostatic chuck.

[0008] 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 de-adsorbed from the electrostatic chuck and after adsorption, respectively, and to determine the stability of the electrostatic chuck based on the capacitance value 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. The first capacitance detector is used to detect the capacitance value between the first adsorption electrode and the DC power supply after the wafer is desorbed from the electrostatic chuck and after adsorption, respectively, and to determine the stability of the electrostatic chuck based on the capacitance value before adsorption and the capacitance value after adsorption.

[0011] 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 from the electrostatic chuck and after adsorption, respectively, and to determine the stability of the electrostatic chuck based on the capacitance value before adsorption and the capacitance value 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 capacitive detector, and the second DC filter is connected between the second adsorption electrode and the second capacitive detector.

[0014] Optionally, the first DC filter includes a first resistor and a first capacitor, 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 the first end of the first capacitor, and a 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. The second end of the second capacitor is grounded.

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

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

[0018] After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

[0019] Optionally, the step of detecting the capacitance between the adsorption electrode and the DC power supply after the wafer desorbs from and after adsorption from the electrostatic chuck, and determining the stability of the electrostatic chuck based on the capacitance before and after adsorption, includes:

[0020] After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the first adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

[0021] After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the second adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

[0022] Optionally, after the semiconductor process equipment completes the process, and the wafer desorbs from the electrostatic chuck, and after supplying auxiliary gas to the process chamber, the method further includes:

[0023] After the wafer desorbs from or after it adsorbs from 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 detected respectively. The abnormal state of the electrostatic chuck is judged based on the first capacitance value and the second capacitance value.

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

[0025] 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 the bottom of the electrostatic chuck is covered with ions.

[0026] 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.

[0027] 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 circuit between the electrostatic chuck and the DC power supply will detach.

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

[0029] One or more processors;

[0030] Memory, used to store 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 electrostatic chuck stability detection method as described in any embodiment of the present invention.

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

[0033] The technical solution of this invention involves, after the semiconductor process equipment finishes processing the wafer, de-adsorbing the wafer from the electrostatic chuck, and then introducing auxiliary gas into the process chamber. The capacitance value detected by the capacitance detection module at the connection between the DC power supply and the electrostatic chuck is monitored and observed in real time. The wafer to be etched is then placed in and adsorbed, and the capacitance value detected by the capacitance detection module is observed again. The stability of the electrostatic chuck is determined based on the capacitance values ​​before and after adsorption. This semiconductor process equipment enables the determination of the stability of the electrostatic chuck within the process chamber, ensuring the functional stability of the electrostatic chuck during each wafer etching process. In summary, this invention solves the problem that existing semiconductor process equipment cannot determine the stability of the electrostatic chuck.

[0034] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

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

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

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

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

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

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

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

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

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

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0047] Figure 1 This is a schematic diagram of a semiconductor process equipment according to an embodiment of the present invention, with reference to... Figure 1 This invention provides a semiconductor process apparatus, 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 provided in the process chamber 20. A DC power supply 40 is connected to the electrostatic chuck 30. The DC power supply 40 is used to power the electrostatic chuck 30. The electrostatic chuck 30 is used to adsorb the wafers 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 deliver auxiliary gas to the process chamber 20 after the semiconductor process equipment has finished the process and the wafer has desorbed from the electrostatic chuck 30.

[0050] The capacitance detection module 50 is connected between the adsorption electrode 31 and the DC power supply 40 in the electrostatic chuck 30. The capacitance detection module 50 is used to detect the capacitance value between the adsorption electrode 31 and the DC power supply 40 after the wafer is de-adsorbed and after adsorption, respectively, and to determine the stability of the electrostatic chuck 30 based on the capacitance value before and after adsorption.

[0051] Specifically, the process chamber 20 is grounded, and an electrostatic chuck 30 is installed inside the process chamber 20. The electrostatic chuck 30 has an embedded adsorption electrode 31, and a wafer is adsorbed on its surface. When the semiconductor process equipment processes the wafer, the DC power supply 40 provides a high-voltage DC current (HV) to the electrostatic chuck 30. Under the action of the high-voltage DC current, the electrostatic chuck 30 adsorbs the wafer placed on its surface.

[0052] During wafer etching and other processing steps, the wafer is placed on an electrostatic chuck 30 within the process chamber 20. A DC power supply 40 applies an adsorption voltage to the adsorption electrodes 31 inside the electrostatic chuck 30, causing the wafer to be adsorbed and fixed onto the chuck 30 by electrostatic adsorption force. Etching and other processing steps are then performed on the wafer. After etching and other processes are completed, the adsorption voltage applied to the adsorption electrodes 31 of the electrostatic chuck 30 is stopped, and a reverse voltage is applied to the adsorption electrodes 31 to eliminate the electrostatic adsorption force on the chuck 30, causing the wafer to desorb from the chuck 30 and be removed from the process chamber 20. When the next wafer enters the process chamber 20, the process of adsorbing and fixing it onto the electrostatic chuck 30 is repeated before processing the next wafer.

[0053] After the wafer processing equipment completes the wafer processing, and the wafer is de-adsorbed from the electrostatic chuck 30, auxiliary gas is introduced into the process chamber 20 to maintain its uniformity and stability. The capacitance detection module 50 at the connection point between the DC power supply 40 and the electrostatic chuck 30 is observed, and the capacitance value detected by the module 50 is monitored in real time. The wafer to be etched is then placed in and adsorbed, and the capacitance value detected by the module 50 is observed again. Under stable conditions, the capacitance value before and after adsorption should remain essentially unchanged. The stability of the electrostatic chuck 30 is determined based on these two capacitance values. This semiconductor processing equipment achieves the determination of the stability of the electrostatic chuck 30 within the process chamber 20.

[0054] Optionally, the capacitance value before adsorption ranges from 3.5nF ± 0.5nF, and the capacitance value after adsorption ranges from 4.5nF ± 0.5nF. For example, under conditions of 200 mTorr pressure and 200 sccm O2, the capacitance detection module 50 can achieve a capacitance value range of 3.5nF ± 0.5nF before adsorption and 4.5nF ± 0.5nF after adsorption, indicating that the stability of the electrostatic chuck 30 meets the requirements, and confirming the consistency and stability of the electrostatic chuck 30 before and after processing.

[0055] For example, a significant increase in the reading of the capacitance detection module 50 might be due to the downward displacement of the electrostatic chuck 30 or ion accumulation on the lower surface of the electrostatic chuck 30. Based on the capacitance value detected by the capacitance detection module 50, it can be determined whether the next wafer processing step can continue. The abnormal fluctuations in the capacitance detection value can help identify the problem and then address it specifically.

[0056] The technical solution of this invention involves, after the semiconductor process equipment finishes processing the wafer, de-adsorbing the wafer from the electrostatic chuck, and then introducing auxiliary gas into the process chamber. The capacitance value detected by the capacitance detection module at the connection between the DC power supply and the electrostatic chuck is monitored and observed in real time. The wafer to be etched is then placed in and adsorbed, and the capacitance value detected by the capacitance detection module is observed again. The stability of the electrostatic chuck is determined based on the capacitance values ​​before and after adsorption. This semiconductor process equipment enables the determination of the stability of the electrostatic chuck within the process chamber, ensuring the functional stability of the electrostatic chuck during each wafer etching process. In summary, this invention solves the problem that existing semiconductor process equipment cannot determine the stability of the electrostatic chuck.

[0057] Figure 2 This is a schematic diagram of the structure of another semiconductor process equipment provided according to an embodiment of the present invention, with reference 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 after the wafer is de-adsorbed and after adsorption, respectively, and to determine the stability of the electrostatic chuck 30 based on the capacitance value before adsorption and the capacitance value 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 after the wafer is de-adsorbed and after adsorption, respectively, and to determine the stability of the electrostatic chuck 30 based on the capacitance value before adsorption and the capacitance value 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 an appropriate voltage to the positive and negative electrodes, the balance of the adsorption forces of the positive and negative electrodes 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 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 its uniformity and stability. The first capacitance detector 51 and the second capacitance detector 52 at the connection points between the DC power supply 40 and the first and second adsorption electrodes 301 and 302 are observed in real time. The capacitance values ​​detected by the first and second capacitance detectors 51 and 52 are monitored and observed. The wafer to be etched is then placed in and adsorbed, and the capacitance values ​​detected by the first and second capacitance detectors 51 and 52 are observed again. Under stable conditions, the capacitance values ​​of the first and second capacitance detectors 51 and 52 before and after adsorption should remain essentially unchanged. The stability of the electrostatic chuck 30 is determined based on these capacitance values. This semiconductor process equipment achieves the determination of the stability of the electrostatic chuck 30 within the process chamber 20.

[0062] For example, under the conditions of a pressure of 200 mTorr and 200 sccm O2, the capacitance values ​​of the first capacitance detector 51 and the second capacitance detector 52 can be in the range of 3.5 nF ± 0.5 nF before adsorption and 4.5 nF ± 0.5 nF after adsorption. This indicates 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, the cleaning steps cannot completely remove residual charge, and inconsistencies in the capacitance detectors result in slight differences between the two detectors, which is within the normal range. For example, if the capacitance values ​​detected by the positive and negative capacitance detectors are 3.4nF and 3.5nF respectively, this is within the normal range. It should be noted that a difference of less than 0.2nF between the capacitance values ​​detected by the two detectors is acceptable.

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

[0065]

[0066] Where C is the capacitance value, ε is the dielectric constant, A is the common area of ​​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 and distance between the electrostatic chuck and the wafer, as well as the dielectric constant of the electrostatic chuck material.

[0068] When the first and second capacitance detectors detect abnormal capacitance values, the possible abnormal situations are as follows:

[0069] Figure 3This is a schematic diagram illustrating an abnormal situation in the first type of electrostatic chuck provided according to an embodiment of the present invention, for reference. Figure 3 , Figure 3 This illustrates a situation where the process chamber was not adequately cleaned, resulting in the presence of ions on the base of the electrostatic chuck. Changes in the charge on the electrostatic chuck cause changes in its capacitance value; a slight difference exists between the capacitance values ​​detected by the first and second capacitance detectors, which is normally within the acceptable range of 0.2 nF.

[0070] Figure 4 This is a schematic diagram illustrating an abnormal situation in the second type of electrostatic chuck provided according to an embodiment of the present invention. (Refer to...) Figure 4 , Figure 4 This illustrates a scenario where the wafer is not horizontally positioned or there is a small obstruction between the wafer and the electrostatic chuck. This horizontal positioning or the presence of a small obstruction causes slight differences in the readings of the two capacitance detectors.

[0071] Figure 5 This is a schematic diagram illustrating an abnormal situation in the third type of electrostatic chuck provided according to an embodiment of the present invention. (Refer to...) Figure 5 , Figure 5 This illustrates a situation where the wiring between the electrostatic chuck and the DC power supply has become detached. If the reading of one capacitance detector is significantly higher than that of another (e.g., one reading is in the nF range while the other is in the uF range), this could be due to the wiring between the electrostatic chuck and the DC power supply becoming detached.

[0072] Under conditions of 200 mTorr pressure and 200 sccm O2, the capacitance value before adsorption in semiconductor process equipment can range from 3.5 nF ± 0.5 nF, and the capacitance value after adsorption can range from 4.5 nF ± 0.5 nF. Similarly, this applies to all types of equipment. If the data recorded by the first and second capacitance detectors exceeds 10 nF at any point during operation, the process chamber should be opened immediately for further processing.

[0073] Figure 6 This is a schematic diagram illustrating the working principle of a DC power supply according to an embodiment of the present invention. (Refer to...) Figure 6 The HV terminals of the DC power supply are independently separated. Figure 6 The circuit path is shown, starting from the positive power supply, passing through the positive plate, the negative plate, and finally to the inner wall of the process chamber, which is grounded.

[0074] During wafer processing, a DC power supply generates a high-voltage DC current, which, after passing through a capacitance detection module, is connected to the adsorption electrode in the electrostatic chuck, charging the electrode and thus adsorbing the wafer. Under the excitation of an RF coil within the process chamber, a plasma radio frequency (RF) signal is generated. After the process is completed, the plasma within the process chamber is maintained by gas components in the semiconductor process equipment, ensuring a continuous RF environment. This allows for an electrical connection between the upper surface of the electrostatic chuck and the process chamber via the plasma. Since the process chamber is grounded, the upper surface of the electrostatic chuck is effectively grounded at this point.

[0075] Due to the presence of negative bias, when semiconductor process equipment is used with pulsed functions, the alternating negative bias voltage may momentarily reach above 2kV, causing excessive voltage inside the process chamber and resulting in arcing. This can also leave black marks on the bottom of the electrostatic chuck or cause it to break down, forming cracks. Furthermore, it alters the normal impedance environment of the chamber, causing the matching circuit to exceed its impedance matching range and affecting normal process operation.

[0076] Figure 7 This is a schematic diagram of another semiconductor process equipment provided according to an embodiment of the present invention, with reference 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 a radio frequency filter. By filtering out radio frequency signals through the radio frequency filter, the radio frequency environment leakage in the process chamber 20 is avoided, which may affect or damage the human body and other equipment (such as the DC power supply 40 and the capacitance detection module 50).

[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 capacitor detector 52. The second end of the second resistor R2 is connected to the first end of the second capacitor C2. The second end of the second capacitor C2 is grounded.

[0081] Specifically, the first resistor R1 and the first capacitor C1 constitute the first RC filter circuit, and the second resistor R2 and the second capacitor C2 constitute the second RC filter circuit. The RC filter circuit utilizes the charging and discharging characteristics of the capacitors to filter out high-frequency components in the input signal, outputting a relatively stable DC signal. By adjusting the values ​​of the resistors and capacitors, different filtering effects can be achieved.

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

[0083] S110. After the semiconductor process equipment finishes processing and the wafer is desorbed from the electrostatic chuck, auxiliary gas is delivered to the process chamber.

[0084] Specifically, in combination Figure 1 After the semiconductor process equipment finishes processing the wafer, 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 the electrostatic chuck and after adsorption, the capacitance between the adsorption electrode and the DC power supply is measured respectively, and the stability of the electrostatic chuck is judged based on the capacitance before adsorption and the capacitance after adsorption.

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

[0087] For example, under the conditions of a pressure of 200 mTorr and 200 sccm O2, the capacitance value of the capacitance detection module 50 before adsorption can be 3.5 nF ± 0.5 nF, and the capacitance value after adsorption can be 4.5 nF ± 0.5 nF. This indicates 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 method for detecting the stability of an electrostatic chuck provided in this embodiment of the invention is used to control the semiconductor process equipment provided in this embodiment of the invention. Therefore, the above-mentioned method for detecting the stability of an electrostatic chuck has the same beneficial effects as the semiconductor process equipment, and will not be described again here.

[0089] Based on the above embodiments, the present invention further refines step S120, which will be described in detail below, but this is not intended to limit the present invention.

[0090] S120. After the wafer is desorbed from the electrostatic chuck and after adsorption, the capacitance between the adsorption electrode and the DC power supply is measured respectively. The stability of the electrostatic chuck is determined based on the capacitance before and after adsorption, including:

[0091] After the wafer desorbs from the electrostatic chuck and after adsorption, the capacitance between the first adsorption electrode and the DC power supply is measured. The stability of the electrostatic chuck is then determined based on the capacitance values ​​before and after adsorption.

[0092] After the wafer desorbs from the electrostatic chuck and after adsorption, the capacitance between the second adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

[0093] Specifically, in combination Figure 2 The first capacitance detector 51 and the second capacitance detector 52 at the connection points between the DC power supply 40 and the first adsorption electrode 301 and the second adsorption electrode 302 are observed. The capacitance values ​​detected by the first capacitance detector 51 and the second capacitance detector 52 are monitored and observed in real time. A wafer to be etched is placed in the device and adsorbed, and the capacitance values ​​detected by the first capacitance detector 51 and the second capacitance detector 52 are observed again. Under stable conditions, the capacitance values ​​of the first capacitance detector 51 and the second capacitance detector 52 before and after adsorption should remain essentially unchanged. The stability of the electrostatic chuck 30 is determined based on the capacitance values ​​before and after adsorption. This semiconductor process equipment realizes the determination of the stability of the electrostatic chuck 30 within the process chamber 20.

[0094] For example, under the conditions of a pressure of 200 mTorr and 200 sccm O2, the capacitance values ​​of the first capacitance detector 51 and the second capacitance detector 52 can be in the range of 3.5 nF ± 0.5 nF before adsorption and 4.5 nF ± 0.5 nF after adsorption. This indicates 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, 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 completes the process, and the wafer is desorbed from the electrostatic chuck, and after the auxiliary gas is supplied to the process chamber, the process further includes:

[0097] After the wafer is desorbed from or after it is adsorbed by 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 detected respectively. The abnormal state of the electrostatic chuck is judged based on the first capacitance value and the second capacitance value.

[0098] Optionally, judging the abnormal state of the electrostatic chuck based on 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 will be 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, the circuit between the electrostatic chuck and the DC power supply will become disconnected.

[0102] Specifically, in combination Figure 3 , Figure 3 This illustrates a situation where the process chamber was not adequately cleaned, resulting in the presence of ions on the base of the electrostatic chuck. Changes in the charge on the electrostatic chuck cause changes in its capacitance value; a slight difference exists between the capacitance values ​​detected by the first and second capacitance detectors, which is normally within the acceptable range of 0.2 nF.

[0103] Combination Figure 4 , Figure 4 This illustrates a scenario where the wafer is not horizontally positioned or there is a small obstruction between the wafer and the electrostatic chuck. This horizontal positioning or the presence of a small obstruction causes slight differences in the readings of the two capacitance detectors.

[0104] Combination Figure 5 , Figure 5 This illustrates a situation where the wiring between the electrostatic chuck and the DC power supply has become detached. If the reading of one capacitance detector is significantly higher than that of another (e.g., one reading is in the nF range while the other is in the uF range), this could be due to the wiring between the electrostatic chuck and the DC power supply becoming detached.

[0105] Figure 9A schematic diagram of an electronic device 1, which can be used to implement 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, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

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

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

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

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

[0110] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0111] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

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

[0113] 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 pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, 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 sound input, voice input, or tactile input).

[0114] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0115] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the 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 cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0116] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0117] The specific embodiments described above do not constitute a limitation on the scope of protection of this 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 principles of this invention should be included within the scope of protection of this invention.

Claims

1. A semiconductor process apparatus, characterized in that, include: Gas components, process chamber, DC power supply, and capacitor detection module; An electrostatic chuck is provided in the process chamber. The DC power supply is connected to the electrostatic chuck. The DC power supply is used to power the electrostatic chuck. The electrostatic chuck is used to adsorb the wafers 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 has completed the process and the wafer has 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 de-adsorbed from the electrostatic chuck and after adsorption, respectively, and to determine the stability of the electrostatic chuck based on the capacitance value before and 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. The first capacitance detector is used to detect the capacitance value between the first adsorption electrode and the DC power supply after the wafer is desorbed from the electrostatic chuck and after adsorption, respectively, and to determine the stability of the electrostatic chuck based on 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 from the electrostatic chuck and after adsorption, respectively, and to determine 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, It 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 capacitive detector, and the second DC filter is connected between the second adsorption electrode and the second capacitive 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. 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. The second end of the first capacitor is grounded. 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. The second end of the second capacitor is grounded.

5. A method for detecting the stability of an electrostatic chuck, characterized in that, The detection method, applied to the semiconductor process equipment according to any one of claims 2-4, comprises: After the semiconductor process equipment completes the process and the wafer is desorbed from the electrostatic chuck, auxiliary gas is supplied to the process chamber. After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

6. The method according to claim 5, characterized in that, The step of detecting the capacitance between the adsorption electrode and the DC power supply after the wafer desorbs from and after adsorption, and determining the stability of the electrostatic chuck based on the capacitance before and after adsorption, includes: After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the first adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption. After the wafer desorbs from the electrostatic chuck and after it adsorbs, the capacitance between the second adsorption electrode and the DC power supply is measured, and the stability of the electrostatic chuck is determined based on the capacitance before and after adsorption.

7. The method according to claim 5, characterized in that, After the semiconductor process equipment completes the process, and the wafer desorbs from the electrostatic chuck, and after supplying auxiliary gas to the process chamber, the process further includes: After the wafer desorbs from or after it adsorbs from 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 detected respectively. The 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 step of judging the abnormal state of the electrostatic chuck based on 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 the range of the first preset value, then the bottom of the electrostatic chuck is covered with ions. 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. 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 circuit between the electrostatic chuck and the DC power supply will detach.

9. An electronic device, characterized in that, include: One or more processors; Memory, used to store 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 an electrostatic chuck as described in any one of claims 5-8.

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

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