Gap measurement method and device

Abstract

The present application provides a gap measurement method, which is applied to a measurement module. The measurement module includes a metal shell, an upper electrode, a circuit board, a measurement circuit and a lower electrode are arranged in the metal shell, the circuit board is fixedly connected to the shell, there is a gap between the circuit board and the bottom of the shell, the measurement circuit is located on the circuit board, the upper electrode and the lower electrode are respectively electrically connected to the measurement circuit located on the circuit board, and the upper electrode and the lower electrode are located on opposite sides of the circuit board; the method includes the following steps: based on the upper electrode, obtaining preliminary gap data measured by the measurement circuit; based on the lower electrode, obtaining compensation gap data measured by the measurement circuit; and calculating the target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data. The present application realizes the function of more accurately measuring the gap distance between the bearing base and the target conductor component and the parallelism of the two planes, thereby improving the production quality of the product.

Description

Technical Field

[0001] The present application relates to the field of semiconductor integrated circuit manufacturing technology and industrial measurement in the high-end equipment manufacturing industry, and in particular to a gap measurement method and device. Background Art

[0002] As the size of semiconductor components continues to shrink, advanced semiconductor integrated circuit process etching equipment is facing huge challenges in the wafer manufacturing etching process. To ensure product consistency and maximum productivity, many key process steps rely on precise gap distance measurement between the base on which the substrate or wafer is placed and the target conductor component and the parallelism adjustment of the two planes.

[0003] In the related art, a common method for measuring gap and parallelism is to calibrate and measure the position through the motor drive pulse and lead screw pitch in the machine servo system, and to measure the inclination angle relative to the horizontal position through a level meter.

[0004] However, the measurement accuracy of the above measurement method is relatively low. When measuring the gap, the motor drive pulse needs to be adjusted multiple times. The adjustment is cumbersome and time-consuming. The adjustment process will also introduce greater measurement errors and cannot fully guarantee the consistency of the product production process. Therefore, there is still room for improvement. Summary of the invention

[0005] The purpose of the present application is to provide a gap measurement method and device to achieve a more accurate measurement of the gap distance between a bearing base and a target conductor component and the parallelism of two planes, thereby improving the production quality of the product.

[0006] In order to achieve the purpose of this application, on the one hand, the technical solution adopted in this application is:

[0007] A gap measurement method is applied to a measurement module, the measurement module comprises a metal shell, an upper electrode, a circuit board, a measurement circuit and a lower electrode are arranged in the metal shell, the circuit board is fixedly connected to the metal shell, there is a gap between the circuit board and the bottom of the metal shell, the measurement circuit is located on the circuit board, the upper electrode and the lower electrode are electrically connected to the measurement circuit respectively, and the upper electrode and the lower electrode are located on opposite sides of the circuit board; the method comprises the following steps:

[0008] Based on the upper electrode, obtaining preliminary gap data measured by the measurement circuit, the preliminary gap data being used to indicate a first distance between the upper electrode and a target conductor component;

[0009] Based on the lower electrode, obtaining compensation gap data measured by the measurement circuit, wherein the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell;

[0010] The target gap data is calculated according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data.

[0011] Further, the obtaining preliminary gap data measured by the measurement circuit based on the upper electrode includes:

[0012] The measuring circuit applies an excitation voltage signal to the upper electrode so as to form a first capacitor between the upper electrode and the target conductor component, and the measuring circuit samples the capacitance value of the first capacitor to obtain first sampling data, wherein the first sampling data is used to indicate the gap between the upper electrode and the target conductor component currently measured;

[0013] By adjusting the excitation voltage multiple times so that the measurement circuit measures and obtains a plurality of first sampling data;

[0014] An average operation is performed on a plurality of the first sampling data to obtain effective preliminary gap data.

[0015] Further, the obtaining the compensation gap data measured by the measurement circuit based on the lower electrode includes:

[0016] The measuring circuit applies an excitation voltage to the lower electrode so as to form a second capacitor between the lower electrode and the bottom of the metal shell, and the measuring circuit samples the capacitance value of the second capacitor to obtain second sampling data, wherein the second sampling data is used to indicate the gap between the lower electrode and the bottom of the metal shell currently measured;

[0017] By adjusting the excitation voltage multiple times so that the measurement circuit measures and obtains multiple second sampling data;

[0018] Performing an average operation on a plurality of the second sampling data to obtain valid second sampling data;

[0019] The compensation gap data is calculated based on the effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data.

[0020] Further, the compensation gap data is calculated based on the effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data, including:

[0021] The effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data are input into the preset first calculation model, and the calculation formula based on the preset first calculation model is: Dr=kr(dr-dt)+T+br, wherein Dr is the compensation gap data, dr is the actual gap between the lower electrode and the bottom of the metal shell, dt is the effective second sampling data, T is the preset environmental factor influence data, and kr and br are the preset second reference adjustment data;

[0022] The compensation gap data is calculated by the preset first calculation model.

[0023] Further, the target gap data is calculated according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data, including:

[0024] The valid preliminary gap data, the compensation gap data and the preset first reference adjustment data are input into a preset second calculation model, and the calculation formula based on the preset second calculation model is: D=d+k*Dr+b, wherein D is the target gap data, d is the valid preliminary gap data, k and b are the preset first reference adjustment data, and Dr is the compensation gap data;

[0025] The target gap data is calculated by the preset second calculation model.

[0026] On the other hand, the technical solution adopted in this application is:

[0027] A gap measuring device comprises a measuring module, the measuring module comprises a metal shell, an upper electrode, a circuit board, a measuring circuit and a lower electrode are arranged in the metal shell, the circuit board is fixedly connected to the shell, there is a gap between the circuit board and the bottom of the shell, the measuring circuit is located on the circuit board, the upper electrode and the lower electrode are electrically connected to the measuring circuit respectively, and the upper electrode and the lower electrode are located on opposite sides of the circuit board;

[0028] The measuring circuit is used to obtain preliminary gap data measured by the measuring circuit based on the upper electrode, wherein the preliminary gap data is used to indicate a first distance between the upper electrode and a target conductor component;

[0029] The measuring circuit is used to obtain compensation gap data measured by the measuring circuit based on the lower electrode, and the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell;

[0030] The measuring circuit is used for calculating the target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data.

[0031] Further, the measurement circuit includes a multi-channel analog switch sequence circuit, a capacitance-to-digital conversion circuit and a control circuit, the multi-channel analog switch sequence circuit is electrically connected to the upper electrode, the multi-channel analog switch sequence circuit is electrically connected to the lower electrode, the capacitance-to-digital conversion circuit is electrically connected to the multi-channel analog switch sequence circuit, and the capacitance-to-digital conversion circuit is electrically connected to the control circuit;

[0032] When collecting preliminary gap data, the multi-channel analog switch sequence circuit is used to energize the upper electrode so that the upper electrode and the target conductor component form a first capacitor, and collect a first analog signal, the first analog signal includes a first capacitance value of the first capacitor, the first capacitance value is used to calculate the preliminary gap data, and the preliminary gap data is used to indicate a first distance between the upper electrode and the target conductor component;

[0033] When collecting the compensation gap data, the multi-channel analog switch sequence circuit is used to energize the lower electrode so that the lower electrode and the bottom of the metal shell form a second capacitor, and collect a second analog signal, the second analog signal includes a second capacitance value of the second capacitor, the second capacitance value is used to calculate the compensation gap data, and the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell;

[0034] The capacitance-to-digital conversion circuit is used to convert the first analog signal into a first digital signal, and convert the second analog signal into a second digital signal;

[0035] The control circuit is used to calculate the preliminary gap data based on the first digital signal, calculate the compensation gap data based on the second digital signal, and calculate the target gap data according to the preliminary gap data, the compensation gap data and preset first reference adjustment data.

[0036] Furthermore, the multi-channel analog switch sequence circuit includes a plurality of analog switch devices, a first part of the plurality of analog switch devices are connected to the upper electrode, a second part of the plurality of analog switch devices are connected to the lower electrode, the plurality of analog switch devices are connected to the control circuit, the control circuit is used to control the opening and closing of the plurality of analog switch devices, the upper electrode is energized when the first part of the analog switch devices are turned on, and the lower electrode is energized when the second part of the analog switch devices are turned on.

[0037] Furthermore, the measurement circuit also includes a processing circuit and a power supply circuit, the processing circuit is connected to the power supply circuit, the power supply circuit is connected to the control circuit, the power supply circuit is used to provide a power supply voltage signal, the processing circuit is connected to the multi-channel analog switch sequence circuit, the processing circuit is connected to the capacitance-to-digital conversion circuit, the processing circuit is used to process the power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and output it to the capacitance-to-digital conversion circuit and the multi-channel analog switch sequence circuit, the control circuit controls the opening of the analog switch device in the first part to apply an excitation voltage signal to the upper electrode so as to form a first capacitor between the upper electrode and the target conductor component, or controls the opening of the analog switch device in the second part to apply an excitation voltage signal to the lower electrode so as to form a second capacitor between the lower electrode and the bottom of the metal shell.

[0038] Further, the processing circuit includes a reference power supply chip and a filtering energy storage capacitor, the filtering energy storage capacitor is connected to the power supply circuit, the filtering energy storage capacitor is connected to the reference power supply chip, and the filtering energy storage capacitor is used to filter the power supply voltage signal provided by the power supply circuit, and output the filtered power supply voltage signal to the reference power supply chip;

[0039] The reference power chip is connected to the capacitance-to-digital conversion circuit, and the reference power chip is connected to the multi-channel analog switch sequence circuit. The reference power chip is used to process the filtered power supply voltage signal to obtain an excitation voltage signal of specified accuracy, and output it to the capacitance-to-digital conversion circuit and the multi-channel analog switch sequence circuit.

[0040] Furthermore, the upper electrode and the lower electrode are arranged in parallel.

[0041] Beneficial effects of this application:

[0042] 1. The present application performs gap measurement by utilizing a measuring module, which includes an upper electrode, a circuit board, a measuring circuit and a lower electrode. The distance between the upper electrode and the target conductor component, i.e., the etching gas spray component in the vacuum chamber, is measured based on the upper electrode. The distance between the lower electrode and the bottom of the metal shell is measured based on the lower electrode. The measured distance value is calculated with a preset first reference adjustment data to obtain target gap data, i.e., the measured data is compensated to obtain more accurate gap data, thereby improving the accuracy of the gap measurement and thus improving the quality of the produced products.

[0043] 2. The present application provides a gap measurement device, which utilizes an upper electrode, a measurement circuit, and a lower electrode to perform gap measurement. It can continuously collect target gap data in a vacuum environment, and quickly and in real time measure the gap between a supporting base and an etching gas spray component in a vacuum chamber, thereby improving the measurement efficiency of the gap measurement device and thus improving the maintenance and adjustment efficiency of semiconductor integrated circuit process etching equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a system framework diagram of the gap measurement device of this application.

[0045] Figure 2 This is the overall flow chart of the gap measurement method of this application.

[0046] Figure 3 A schematic diagram of a flow chart of obtaining preliminary gap data measured by the measurement circuit based on the upper electrode in the gap measurement method of the present application.

[0047] Figure 4 A schematic diagram of a flow chart of obtaining the compensated gap data measured by the measuring circuit based on the lower electrode in the gap measuring method of the present application.

[0048] Figure 5 A flow chart of the gap measurement method of the present application for calculating the compensated gap data based on the effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data.

[0049] Figure 6 The present invention is a flow chart of the gap measurement method of the present invention for calculating target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data.

[0050] Explanation of the reference numerals: 1. measurement circuit; 11. multi-channel analog switch sequence circuit; 12. capacitance-to-digital conversion circuit; 13. control circuit; 14. processing circuit; 141. reference power supply chip; 142. filtering energy storage capacitor; 15. power supply circuit. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which this application belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0052] As the size of semiconductor components continues to shrink, advanced semiconductor integrated circuit process etching equipment is facing huge challenges in the wafer manufacturing etching link. To ensure product consistency and maximum production capacity, many key process steps rely on the precise gap distance measurement between the supporting base for placing the substrate or wafer and the target conductor component and the parallelism adjustment of the two planes. The common way to measure the gap and parallelism is to calibrate and measure the position through the motor drive pulse and lead screw pitch in the machine servo system, that is, the motor driver in the servo system receives the set pulse value and drives the motor to move, so that the top of the base connected to the motor is at the same height as the bottom of the target conductor component. This is recorded as the zero point, and then the motor is driven back to move. The actual moving distance of the base can be converted by the number of drive pulses and the lead screw pitch, that is, the gap distance between the base and the target conductor component. And the inclination angle relative to the horizontal position is measured by a level. Limited by the motor drive pulse and lead screw pitch, and unable to be calibrated in an actual vacuum environment, the measurement accuracy is low and the error is large. As the size of semiconductor components continues to shrink, even a small error will cause the product to fail to meet the process requirements.

[0053] This embodiment provides a gap measurement device, referring to Figure 1 , which is used to be placed on a supporting base in a vacuum chamber to measure the gap between the supporting base and a target conductor component. In this embodiment, the target conductor component is an etching gas spray component in the vacuum chamber.

[0054] The gap measuring device comprises a measuring module, which comprises a metal shell, in which an upper electrode, a circuit board, a measuring circuit 1 and a lower electrode are arranged, the circuit board is fixedly connected to the shell, there is a gap between the circuit board and the bottom of the shell, the measuring circuit 1 is located on the circuit board, the upper electrode and the lower electrode are electrically connected to the measuring circuit 1 respectively, and the upper electrode and the lower electrode are located on opposite sides of the circuit board. The measuring circuit 1 comprises a multi-channel analog switch sequence circuit 11, a capacitance digital conversion circuit 12, a control circuit 13, a processing circuit 14 and a power supply circuit 15, wherein the power supply circuit 15 is connected to the processing circuit 14, the power supply circuit 15 is connected to the control circuit 12, the power supply circuit 15 is used to provide a power supply voltage signal to the control circuit 13 and the processing circuit 14, the processing circuit 14 is connected to the multi-channel analog switch sequence circuit 11, the processing circuit 14 is connected to the capacitance digital conversion circuit 12, the processing circuit 14 is used to process the power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and output it to the capacitance digital conversion circuit 12 and the multi-channel analog switch sequence circuit 11.

[0055] The capacitance-to-digital conversion circuit 12 is electrically connected to the control circuit 13, the multi-channel analog switch sequence circuit 11 is electrically connected to the capacitance-to-digital conversion circuit 12, the multi-channel analog switch sequence circuit 11 is electrically connected to the upper electrode, and the multi-channel analog switch sequence circuit 11 is electrically connected to the lower electrode. The control circuit 13 applies an excitation voltage signal to the upper electrode through the multi-channel analog switch sequence circuit 11, so that a first capacitor is formed between the upper electrode and the etching gas spray component in the vacuum chamber. The control circuit 13 applies an excitation voltage signal to the lower electrode through the multi-channel analog switch sequence circuit 11, so that a second capacitor is formed between the lower electrode and the bottom of the metal shell. The multi-channel analog switch sequence circuit 11 is used to collect analog capacitance signals of the first capacitor and the second capacitor. The capacitance-to-digital conversion circuit 12 is used to convert the analog capacitance signal into a digital signal and transmit the digital signal to the control circuit 13. The control circuit 13 calculates preliminary gap data and compensation gap data according to the digital signal. The preliminary gap data is used to indicate a first distance between the upper electrode and the etching gas spray component in the vacuum chamber, and the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell. The control circuit 13 can calculate the target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data.

[0056] In this embodiment, the multi-channel analog switch sequence circuit 11 includes a plurality of analog switch devices, the first part of the analog switch devices in the plurality of analog switch devices is connected to the upper electrode, the second part of the analog switch devices in the plurality of analog switch devices is connected to the lower electrode, and the plurality of analog switch devices is connected to the control circuit. The control circuit 13 is used to control the opening and closing of the plurality of analog switch devices. When the first part of the analog switch devices is turned on, the upper electrode is energized, and when the second part of the analog switch devices is turned on, the lower electrode is energized. The control circuit 13 applies an excitation voltage signal to the upper electrode by controlling the opening of the first part of the analog switch devices. When the excitation voltage signal is applied to the upper electrode, a first capacitor is formed between the upper electrode and the etching gas spraying component in the vacuum chamber. The control circuit 13 applies an excitation voltage signal to the lower electrode by controlling the opening of the second part of the analog switch devices. When the excitation voltage signal is applied to the lower electrode, a second capacitor is formed between the lower electrode and the bottom of the metal shell. The control circuit 13 can perform gating control on the plurality of analog switch devices, so that the gap measurement device can selectively control the specified analog switch device, so that the gap measurement device can selectively control the power-on of at least one upper electrode or a lower electrode, thereby improving the flexibility of the gap measurement device.

[0057] At least three upper electrodes can be used to measure the gap distances between three different positions on the carrier base and the etching gas spray component in the vacuum chamber. Through the gap distances between the three different positions on the carrier base and the etching gas spray component in the vacuum chamber, it can be determined whether the carrier base is parallel to the lower surface of the etching gas spray component in the vacuum chamber. If the gap distances between the three different positions on the carrier base and the etching gas spray component in the vacuum chamber are equal, it means that the carrier base is parallel to the lower surface of the etching gas spray component in the vacuum chamber.

[0058] Specifically, during measurement, the operator places the gap measurement device on the supporting base in the vacuum chamber, the control circuit 13 controls the specified analog switch device to turn on, the power supply circuit 15 provides a power supply voltage signal, the processing circuit 14 processes the power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and outputs it to the capacitance digital conversion circuit 12 and the multi-channel analog switch sequence circuit 11, the control circuit 13 applies an excitation voltage signal to the upper electrode by controlling the opening of the first part of the analog switch device, so that a first capacitor is formed between the upper electrode and the etching gas spray component in the vacuum chamber, and the multi-channel analog switch sequence circuit 11 collects the first analog signal, and the first analog signal includes the first capacitance value of the first capacitor. At the same time, the control circuit 13 applies an excitation voltage signal to the lower electrode by controlling the opening of the second part of the analog switch device, so that a second capacitor is formed between the lower electrode and the bottom of the metal shell, and the multi-channel analog switch sequence circuit 11 collects the second analog signal, and the second analog signal includes the second capacitance value of the second capacitor. The capacitance digital conversion circuit 12 converts the first analog signal into a first digital signal and converts the second analog signal into a second digital signal.

[0059] The control circuit 13 calculates and obtains the first sampling data based on the first digital signal. The first sampling data is used to indicate the gap between the currently measured upper electrode and the etching gas spray component in the vacuum chamber. By adjusting the excitation voltage multiple times, the measurement circuit 1 can measure multiple first sampling data, and the multiple first sampling data are averaged to obtain effective preliminary gap data. The control circuit 13 calculates and obtains the second sampling data based on the second digital signal. The second sampling data is used to indicate the gap between the currently measured lower electrode and the bottom of the metal shell. By adjusting the excitation voltage multiple times, the measurement circuit 1 can measure multiple second sampling data, and the multiple second sampling data are averaged to obtain effective second sampling data. The effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data are input into the preset first calculation model. The calculation formula based on the preset first calculation model is: Dr=kr(dr-dt)+T+br, where Dr is the compensation gap data, dr is the actual gap between the lower electrode and the bottom of the metal shell, dt is the effective second sampling data, T is the preset environmental factor influence data, and the environmental factor influence data is the compensation data set by the operator according to the influence of the ambient temperature and humidity on the measurement, kr and br are the preset second reference adjustment data, and the second reference adjustment data is the adjustment data based on the preset first calculation model set by the operator according to the actual adjustment error. The compensation gap data can be obtained by calculating the preset first calculation model.

[0060] Then, the preset second calculation model is used for calculation. The control circuit 13 inputs the valid preliminary gap data, the compensation gap data and the preset first reference adjustment data into the preset second calculation model. The calculation formula based on the preset second calculation model is: D=d+k*Dr+b, wherein D is the target gap data, d is the valid preliminary gap data, k and b are the preset first reference adjustment data, the first reference adjustment data is the adjustment data based on the preset second calculation model set by the operator according to the actual adjustment error, and Dr is the compensation gap data; the target gap data can be obtained by calculating with the preset second calculation model, thereby obtaining the accurate gap value between the supporting base and the etching gas spray component in the vacuum chamber.

[0061] Further, the processing circuit 14 includes a reference power chip 141 and a filter energy storage capacitor 142, the filter energy storage capacitor is connected to the power circuit, the filter energy storage capacitor is connected to the reference power chip, and the filter energy storage capacitor is used to filter the power supply voltage signal provided by the power circuit, and output the filtered power supply voltage signal to the reference power chip. The reference power chip is connected to the capacitance digital conversion circuit 12, the reference power chip 141 is connected to the multi-channel analog switch sequence circuit 11, and the reference power chip is used to process the filtered power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and output it to the capacitance digital conversion circuit and the multi-channel analog switch sequence circuit 11. The reference power chip 141 provides an excitation voltage signal of a specified accuracy to the capacitance digital conversion circuit 12 and the multi-channel analog switch sequence circuit 11, thereby improving the accuracy of the measurement. The filter energy storage capacitor 142 is connected to the reference power chip 141, and the filter energy storage capacitor 142 plays a filtering role to reduce the influence of electromagnetic interference (EMI) and other noise sources on the circuit, improve the stability of the circuit, and indirectly improve the accuracy of the measurement.

[0062] Furthermore, the upper electrode and the lower electrode are arranged in parallel, thereby ensuring that the gap difference between the upper electrode and the lower electrode does not affect the gap measurement.

[0063] This embodiment also provides a gap measurement method, referring to Figure 2 , applied to the above-mentioned gap measuring device, the method comprises the following steps:

[0064] Step S1: Based on the upper electrode, obtaining preliminary gap data measured by the measurement circuit 1, the preliminary gap data is used to indicate a first distance between the upper electrode and the target conductor component;

[0065] Reference Figure 2 and Figure 3, by applying an excitation voltage to the upper electrode, so that a first capacitor is formed between the upper electrode and the etching gas spray component in the vacuum chamber, the multi-channel analog switch sequence circuit 11 collects the first capacitance value of the first capacitor, that is, the first analog signal, the capacitance digital conversion circuit 12 converts the first analog signal into a first digital signal and transmits it to the control circuit 13, the control circuit 13 can calculate the first sampling data through the first digital signal, and the measurement circuit 1 can measure multiple first sampling data by adjusting the excitation voltage multiple times, and average the multiple first sampling data to obtain effective preliminary gap data. The preliminary gap data is the measured gap value between the upper electrode and the etching gas spray component in the vacuum chamber, which is used to indicate the first distance between the upper electrode and the target conductor component.

[0066] Step S2: Based on the lower electrode, obtaining compensation gap data measured by the measurement circuit 1, the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell;

[0067] Reference Figure 2 and Figure 4 , by applying an excitation voltage to the lower electrode so that a second capacitor is formed between the lower electrode and the bottom of the metal shell, the multi-channel analog switch sequence circuit 11 collects the second capacitance value of the second capacitor, that is, the second analog signal, the capacitance-to-digital conversion circuit 12 converts the second analog signal into a second digital signal and transmits it to the control circuit 13, the control circuit 13 can calculate the second sampling data through the second digital signal, the second sampling data is used to indicate the gap between the currently measured lower electrode and the bottom of the metal shell, and the measurement circuit 1 can measure multiple second sampling data by adjusting the excitation voltage multiple times, and the multiple second sampling data are averaged to obtain the effective second sampling data. The effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data are input into the preset first calculation model. The calculation formula based on the preset first calculation model is: Dr=kr(dr-dt)+T+br, where Dr is the compensation gap data, dr is the actual gap between the lower electrode and the bottom of the metal shell, dt is the effective second sampling data, T is the preset environmental factor influence data, and the environmental factor influence data is the compensation data set by the operator according to the influence of the ambient temperature and humidity on the measurement, kr and br are the preset second reference adjustment data, and the second reference adjustment data is the adjustment data based on the preset first calculation model set by the operator according to the actual adjustment error. The compensation gap data can be calculated by the preset first calculation model. The compensation gap data is the gap value between the lower electrode and the bottom of the metal shell, which is used to indicate the second distance between the lower electrode and the bottom of the metal shell.

[0068] Step S3: Calculate the target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data.

[0069] Reference Figure 2 and Figure 5 , input the valid preliminary gap data, the compensation gap data and the preset first reference adjustment data into the preset second calculation model. The calculation formula based on the preset second calculation model is: D=d+k*Dr+b, wherein D is the target gap data, d is the valid preliminary gap data, k and b are the preset first reference adjustment data, the first reference adjustment data is the adjustment data based on the preset second calculation model set by the operator according to the actual adjustment error, Dr is the compensation gap data, and the target gap data can be obtained by calculating with the preset second calculation model.

[0070] The difference between the target gap data and the reference distance can be kept within the specified tolerance. When the operator adjusts the gap between the support base and the etching gas spray component in the vacuum chamber to the target gap data, it means that the gap between the support base and the etching gas spray component in the vacuum chamber reaches the optimal standard gap. During the adjustment process, the gap measurement device will continue to measure the gap to prompt the operator of the adjustment status in real time.

[0071] Beneficial effects of this application:

[0072] The present application performs gap measurement by utilizing a measuring module, which includes an upper electrode, a circuit board, a measuring circuit and a lower electrode. The distance between the upper electrode and a target conductor component, i.e., an etching gas spray component in a vacuum chamber, is measured based on the upper electrode. The distance between the lower electrode and the bottom of a metal shell is measured based on the lower electrode. The measured distance value is calculated with a preset first reference adjustment data to obtain target gap data, i.e., the measured data is compensated to obtain more accurate gap data, thereby improving the accuracy of the gap measurement and thus being able to improve the quality of the produced products.

[0073] The present application provides a gap measurement device, which uses an upper electrode, a measurement circuit 1 and a lower electrode to perform gap measurement. It can continuously collect target gap data in a vacuum environment, and quickly and in real time measure the gap between a supporting base and an etching gas spray component in a vacuum chamber, thereby improving the measurement efficiency of the gap measurement device and thus improving the maintenance and adjustment efficiency of semiconductor integrated circuit process etching equipment.

[0074] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0075] Although the embodiments of the present application are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present application. Moreover, the present application described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A gap measurement method, characterized in that: The invention is applied to a measuring module, the measuring module comprising a metal shell, an upper electrode, a circuit board, a measuring circuit (1) and a lower electrode are arranged in the metal shell, the circuit board is fixedly connected to the metal shell, there is a gap between the circuit board and the bottom of the metal shell, the measuring circuit (1) is located on the circuit board, the upper electrode and the lower electrode are respectively electrically connected to the measuring circuit (1), and the upper electrode and the lower electrode are located on opposite sides of the circuit board; the method comprises the following steps: Based on the upper electrode, obtaining preliminary gap data measured by the measurement circuit (1), the preliminary gap data being used to indicate a first distance between the upper electrode and a target conductor component; Based on the lower electrode, obtaining compensation gap data measured by the measurement circuit (1), wherein the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell; Calculate target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data; The step of obtaining the compensation gap data measured by the measurement circuit (1) based on the lower electrode comprises: The measuring circuit (1) applies an excitation voltage to the lower electrode so as to form a second capacitor between the lower electrode and the bottom of the metal shell, and the measuring circuit (1) samples the capacitance value of the second capacitor to obtain second sampling data, wherein the second sampling data is used to indicate the gap currently measured between the lower electrode and the bottom of the metal shell; By adjusting the excitation voltage multiple times so that the measurement circuit (1) measures and obtains multiple second sampling data; Performing an average operation on a plurality of the second sampling data to obtain valid second sampling data; The compensation gap data is calculated according to the effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data; The method of calculating the compensation gap data according to the effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data includes: The effective second sampling data, the actual gap between the lower electrode and the bottom of the metal shell, the preset second reference adjustment data and the preset environmental factor influence data are input into the preset first calculation model, and the calculation formula based on the preset first calculation model is: Dr=kr(dr-dt)+T+br, wherein Dr is the compensation gap data, dr is the actual gap between the lower electrode and the bottom of the metal shell, dt is the effective second sampling data, T is the preset environmental factor influence data, and kr and br are the preset second reference adjustment data; The compensation gap data is calculated by the preset first calculation model.

2. The gap measurement method according to claim 1, characterized in that: The step of obtaining preliminary gap data measured by the measuring circuit (1) based on the upper electrode comprises: The measuring circuit (1) applies an excitation voltage signal to the upper electrode so as to form a first capacitor between the upper electrode and the target conductor component, and the measuring circuit (1) samples the capacitance value of the first capacitor to obtain first sampling data, wherein the first sampling data is used to indicate the gap between the upper electrode and the target conductor component currently being measured; By adjusting the excitation voltage multiple times so that the measurement circuit (1) measures and obtains multiple first sampling data; An average operation is performed on a plurality of the first sampling data to obtain effective preliminary gap data.

3. The gap measurement method according to claim 1, characterized in that: The step of calculating the target gap data according to the preliminary gap data, the compensation gap data and the preset first reference adjustment data includes: The valid preliminary gap data, the compensation gap data and the preset first reference adjustment data are input into the preset The second calculation model is assumed, and the calculation formula based on the preset second calculation model is: D=d+k*Dr+b, wherein D is the target gap data, d is the effective preliminary gap data, k and b are the preset first reference adjustment data, and Dr is the compensation gap data; The target gap data is calculated by the preset second calculation model.

4. A gap measuring device, used to implement the method according to any one of claims 1 to 3, characterized in that: The measuring module comprises a metal shell, an upper electrode, a circuit board, a measuring circuit (1) and a lower electrode are arranged in the metal shell, the circuit board is fixedly connected to the shell, a gap exists between the circuit board and the bottom of the shell, the measuring circuit (1) is located on the circuit board, the upper electrode and the lower electrode are electrically connected to the measuring circuit (1) respectively, and the upper electrode and the lower electrode are located on opposite sides of the circuit board; The measuring circuit (1) is used to obtain preliminary gap data measured by the measuring circuit (1) based on the upper electrode, wherein the preliminary gap data is used to indicate a first distance between the upper electrode and a target conductor component; The measuring circuit (1) is used to obtain compensation gap data measured by the measuring circuit (1) based on the lower electrode, and the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell; The measuring circuit (1) is used for calculating target gap data according to the preliminary gap data, the compensation gap data and preset first reference adjustment data.

5. The gap measuring device according to claim 4, characterized in that: The measuring circuit (1) comprises a multi-channel analog switch sequence circuit (11), a capacitance-to-digital conversion circuit (12) and a control circuit (13); the multi-channel analog switch sequence circuit (11) is electrically connected to the upper electrode, the multi-channel analog switch sequence circuit (11) is electrically connected to the lower electrode, the capacitance-to-digital conversion circuit (12) is electrically connected to the multi-channel analog switch sequence circuit (11), and the capacitance-to-digital conversion circuit (12) is electrically connected to the control circuit (13); When collecting preliminary gap data, the multi-channel analog switch sequence circuit (11) is used to energize the upper electrode so that the upper electrode and the target conductor component form a first capacitor, and collect a first analog signal, the first analog signal includes a first capacitance value of the first capacitor, the first capacitance value is used to calculate the preliminary gap data, and the preliminary gap data is used to indicate a first distance between the upper electrode and the target conductor component; When collecting the compensation gap data, the multi-channel analog switch sequence circuit (11) is used to energize the lower electrode so that the lower electrode and the bottom of the metal shell form a second capacitor, and collect a second analog signal, the second analog signal includes a second capacitance value of the second capacitor, the second capacitance value is used to calculate the compensation gap data, and the compensation gap data is used to indicate a second distance between the lower electrode and the bottom of the metal shell; The capacitance-to-digital conversion circuit (12) is used to convert the first analog signal into a first digital signal, and convert the second analog signal into a second digital signal; The control circuit (13) is used to calculate the preliminary gap data based on the first digital signal, calculate the compensation gap data based on the second digital signal, and calculate the target gap data according to the preliminary gap data, the compensation gap data and preset first reference adjustment data.

6. The gap measuring device according to claim 5, characterized in that: The multi-channel analog switch sequence circuit (11) comprises a plurality of analog switch devices, wherein a first portion of the analog switch devices among the plurality of analog switch devices are connected to the upper electrode, and a second portion of the analog switch devices among the plurality of analog switch devices are connected to the lower electrode. The plurality of analog switch devices are connected to the control circuit (13), and the control circuit (13) is used to control the opening and closing of the plurality of analog switch devices. When the first portion of the analog switch devices are turned on, the upper electrode is energized, and when the second portion of the analog switch devices are turned on, the lower electrode is energized.

7. The gap measuring device according to claim 6, characterized in that: The measuring circuit (1) further comprises a processing circuit (14) and a power supply circuit (15), wherein the processing circuit (14) is connected to the power supply circuit (15), the power supply circuit (15) is connected to the control circuit (13), the power supply circuit (15) is used to provide a power supply voltage signal, the processing circuit (14) is connected to the multi-channel analog switch sequence circuit (11), the processing circuit (14) is connected to the capacitance-to-digital conversion circuit (12), the processing circuit (14) is used to process the power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and output the signal to the capacitance-to-digital conversion circuit (12) and the multi-channel analog switch sequence circuit (11), and the control circuit (13) controls the opening of the first part of the analog switch devices to apply an excitation voltage signal to the upper electrode, so that a first capacitor is formed between the upper electrode and the target conductor component, or controls the opening of the second part of the analog switch devices to apply an excitation voltage signal to the lower electrode, so that a second capacitor is formed between the lower electrode and the bottom of the metal shell.

8. The gap measuring device according to claim 7, characterized in that: The processing circuit (14) comprises a reference power supply chip (141) and a filtering energy storage capacitor (142), wherein the filtering energy storage capacitor (142) is connected to the power supply circuit (15), and the filtering energy storage capacitor (142) is connected to the reference power supply chip (141), and the filtering energy storage capacitor (142) is used to filter the power supply voltage signal provided by the power supply circuit (15), and output the filtered power supply voltage signal to the reference power supply chip (141); The reference power chip (141) is connected to the capacitance-to-digital conversion circuit (12), and the reference power chip (141) is connected to the multi-channel analog switch sequence circuit (11). The reference power chip (141) is used to process the filtered power supply voltage signal to obtain an excitation voltage signal of a specified accuracy, and output it to the capacitance-to-digital conversion circuit (12) and the multi-channel analog switch sequence circuit (11).

9. The gap measuring device according to claim 4, characterized in that: The upper electrode and the lower electrode are arranged in parallel.

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