Wafer thickness measurement system and method
By working together with the display module, industrial computer, electrical control module and signal acquisition module of the wafer thickness measurement system, the thickness of the wafer can be measured directly, which solves the problem of large measurement error in the existing technology and realizes high-precision measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING TIANKE HEDA SEMICON CO LTD
- Filing Date
- 2023-02-10
- Publication Date
- 2026-05-29
AI Technical Summary
In existing technologies, it is difficult to directly measure the thickness during the double-sided grinding process of wafers, resulting in large measurement errors and poor accuracy.
The wafer thickness measurement system includes a display module, an industrial computer, an electrical control module, and a signal acquisition module. Through the coordinated work of the imaging unit, the gas control unit, and the thickness measurement unit, the thickness of the wafer is measured directly, avoiding indirect measurement of other objects.
This improves the accuracy and reliability of wafer thickness measurement and reduces measurement errors.
Smart Images
Figure CN116230570B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wafer measurement technology, and in particular to a wafer thickness measurement system and method. Background Technology
[0002] A wafer is a silicon wafer used to manufacture silicon semiconductor integrated circuits. Various circuit element structures can be fabricated on silicon wafers, which are then combined to form integrated circuit products. Therefore, wafers are the foundation for manufacturing integrated circuit products, and the thickness of a wafer has a significant impact on its performance.
[0003] In existing technologies, online real-time thickness measurement systems used in the double-sided grinding process of wafers typically cannot contact the workpiece surface and generally employ indirect thickness measurement methods. For example, laser thickness gauges or contact dial indicators are used to measure thickness by real-time monitoring of the thickness changes of the upper and lower grinding discs during processing and calculating the change in wafer removal amount. However, these methods measure the wafer thickness indirectly by measuring other objects, which means that many factors influence the measurement error, resulting in a large error in the measured thickness and thus poor measurement accuracy. Summary of the Invention
[0004] In view of this, embodiments of this application provide a wafer thickness measurement system and method, which aim to improve the accuracy of wafer thickness measurement.
[0005] In a first aspect, embodiments of this application provide a wafer thickness measurement system, the system comprising a display module, an industrial control computer, an electrical control module, and a signal acquisition module; the signal acquisition module includes an image capture unit, a gas control unit, and a thickness measurement unit;
[0006] The display module is used to acquire the initial thickness of the wafer, the target thickness of the wafer, the preset threshold and the thickness measurement time frequency, and to display the thickness test results of the wafer.
[0007] The industrial control computer is used to send test signals to the electrical control module according to the thickness measurement time frequency; send test instructions to the electrical control module according to the comparison result of the image data returned by the electrical control module and the preset image data; receive and calculate the thickness test data to obtain the thickness test result, and send the thickness test result to the display module.
[0008] The electrical control module is used to control the imaging unit to take pictures according to the test signal to obtain the image data and send the image data to the industrial control computer; receive and control the gas control unit and the thickness measurement unit to perform tests according to the test instructions to obtain the thickness test data and send the thickness test data to the industrial control computer.
[0009] The imaging unit is used to take a picture of the wafer in response to the test signal and obtain the image data;
[0010] The gas control unit is used to inject gas into the wafer in response to the test command;
[0011] The thickness measurement unit is used to perform thickness testing on the wafer in response to the test command.
[0012] Optionally, the industrial control computer is specifically used to send a test command to the electrical control module when the comparison result between the image data returned by the electrical control module and the preset image data indicates that the wafer is exposed on the grinding pad.
[0013] Optionally, the electrical control module is specifically used to receive the test command, control the gas control unit to perform gas injection through the test command, and simultaneously control the thickness measurement unit to perform thickness measurement to obtain thickness test data, and send the thickness test data to the industrial control computer.
[0014] Optionally, the thickness measuring unit is specifically used for:
[0015] The thickness measurement unit is used to perform optical thickness testing on the wafer in response to the test command.
[0016] Optionally, the industrial control computer is specifically used to receive the thickness test data, calculate the average value of the valid data of the thickness test data to obtain the thickness test result, and send the thickness test result to the display module, wherein the valid data is the thickness test data where the test thickness is less than or equal to the initial thickness.
[0017] Optionally, the industrial control computer is further used to determine whether the thickness test result is within the target test thickness range. If the thickness test result is within the target test thickness range, a stop signal is sent to the grinding equipment. The target test thickness range is obtained by adding the target thickness and the preset threshold.
[0018] Secondly, embodiments of this application provide a wafer thickness measurement method applied to a wafer thickness measurement system. The wafer thickness measurement system includes a display module, an industrial control computer, an electrical control module, and a signal acquisition module. The signal acquisition module includes an image capture unit, a gas control unit, and a thickness measurement unit. The method includes:
[0019] The display module acquires the initial thickness of the wafer, the target thickness of the wafer, the preset threshold, and the thickness measurement time frequency, and displays the thickness test results of the wafer.
[0020] The industrial control computer sends a test signal to the electrical control module according to the thickness measurement time frequency; the industrial control computer sends a test command to the electrical control module according to the comparison result of the image data returned by the electrical control module and the preset image data; the industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module.
[0021] The electrical control module controls the imaging unit to take pictures according to the test signal to obtain the image data, and sends the image data to the industrial control computer; the electrical control module receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test command to obtain the thickness test data, and sends the thickness test data to the industrial control computer; the imaging unit takes pictures of the wafer in response to the test signal to obtain the image data; the gas control unit sprays gas onto the wafer in response to the test command; the thickness measurement unit performs thickness tests on the wafer in response to the test command.
[0022] Optionally, the industrial control computer sends a test command to the electrical control module based on the comparison result between the image data returned by the electrical control module and the preset image data, including:
[0023] When the industrial control computer determines that the wafer is exposed outside the grinding pad based on the comparison result between the image data returned by the electrical control module and the preset image data, it sends a test command to the electrical control module.
[0024] Optionally, the electrical control module receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test instructions to obtain thickness test data, and sends the thickness test data to the industrial control computer, including:
[0025] The electrical control module receives the test command, controls the gas control unit to inject gas through the test command, and simultaneously controls the thickness measurement unit to measure thickness to obtain thickness test data, and sends the thickness test data to the industrial control computer.
[0026] Optionally, the thickness measurement unit performs a thickness test on the wafer in response to the test command, including:
[0027] The thickness measurement unit performs optical thickness testing on the wafer in response to the test command.
[0028] Optionally, the industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module, including:
[0029] The industrial control computer receives the thickness test data, calculates the average value of the valid data of the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module. The valid data is the thickness test data where the test thickness is less than or equal to the initial thickness.
[0030] Optionally, the method further includes:
[0031] The industrial control computer determines whether the thickness test result is within the target test thickness range. If the thickness test result is within the target test thickness range, it sends a stop signal to the grinding equipment. The target test thickness range is obtained by adding the target thickness and the preset threshold.
[0032] Compared with the prior art, the embodiments of this application have the following beneficial effects:
[0033] This application provides a wafer thickness measurement system and method. The system includes a display module, an industrial control computer, an electrical control module, and a signal acquisition module. The signal acquisition module includes an image capture unit, a gas control unit, and a thickness measurement unit. The display module acquires the initial thickness of the wafer, the target thickness of the wafer, a preset threshold, and the thickness measurement time frequency, and displays the wafer thickness test results. The industrial control computer sends a test signal to the electrical control module according to the thickness measurement time frequency. Based on the comparison between the image data returned by the electrical control module and the preset image data, the industrial control computer sends a test command to the electrical control module, receives and calculates the thickness test data to obtain the thickness test results, and sends the thickness test results to the display module. The electrical control module controls the image capture unit to take pictures according to the test signal to obtain image data, sends the image data to the industrial control computer, receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test command to obtain thickness test data, and sends the thickness test data to the industrial control computer. The image capture unit takes pictures of the wafer in response to the test signal to obtain image data. The gas control unit sprays gas onto the wafer in response to the test command. The thickness measurement unit performs thickness testing on the wafer in response to the test command. The thickness of the wafer can be measured directly during the double-sided grinding process, without the need to measure the thickness indirectly through other objects. This results in high measurement reliability and improved measurement accuracy. Attached Figure Description
[0034] To more clearly illustrate the technical solutions in this embodiment or the prior art, the drawings used in the description of the embodiment or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0035] Figure 1This is a schematic diagram of a wafer thickness measurement system provided in an embodiment of this application;
[0036] Figure 2 A top view of the signal acquisition module provided in an embodiment of this application;
[0037] Figure 3 This is a schematic diagram of the structure of the signal acquisition module provided in an embodiment of this application;
[0038] Figure 4 A schematic diagram of the thickness control interface of the display module provided in an embodiment of this application;
[0039] Figure 5 This is a flowchart of a wafer thickness measurement method provided in an embodiment of this application. Detailed Implementation
[0040] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0041] In existing technologies, online real-time thickness measurement systems used in the double-sided grinding process of wafers typically cannot contact the workpiece surface and generally employ indirect thickness measurement methods. For example, laser thickness gauges or contact dial indicators are used to measure thickness by real-time monitoring of the thickness changes of the upper and lower grinding discs during processing and calculating the change in wafer removal amount. However, these methods measure the wafer thickness indirectly by measuring other objects, which means that many factors influence the measurement error, resulting in a large error in the measured thickness and thus poor measurement accuracy.
[0042] In order to solve the above problems, this application provides a wafer thickness measurement system and method. Through the cooperation of an industrial control computer, an electrical control module, a signal acquisition module and a display module, the thickness of the wafer can be measured directly without the need to measure the thickness indirectly by measuring other objects. The measurement reliability is high and the measurement accuracy is improved.
[0043] See Figure 1 This is a schematic diagram of a wafer thickness measurement system provided in an embodiment of this application. The system includes a display module 101, an industrial computer 102, an electrical control module 103, and a signal acquisition module 104. The signal acquisition module 104 includes an image capture unit 1041, a gas control unit 1042, and a thickness measurement unit 1043. See also... Figure 2 and Figure 3This is a schematic diagram of the signal acquisition module. Figure 2 for Figure 3 Top view, Figure 2 The circle is the wafer used for testing. Figure 3 The circle in the image represents the platform on which the wafer is placed.
[0044] The display module 101 is used to acquire the initial thickness of the wafer, the target thickness of the wafer, the preset threshold and the thickness measurement time frequency, and to display the thickness test results of the wafer.
[0045] In one possible implementation, see Figure 4 , Figure 4 This is a schematic diagram of the thickness control interface of the display module. The initial thickness, target thickness, preset threshold, and thickness measurement time frequency of the wafer can be input into the display module 101. The preset threshold can be an allowable error range, such as ±0.5 micrometers. The thickness measurement time frequency represents the frequency of measurement during the double-sided grinding process. The thickness measurement time frequency can be set using a thickness gauge. As an example, the thickness measurement time frequency could be one test per minute, with 10 tests per round. The test time could be 20:56:07. Test data is then input sequentially for tests 1 to 10, and the valid data for each round is marked. Valid data specifically refers to thickness test data where the measured thickness is less than or equal to the initial thickness. Furthermore, as an example... Figure 4 The test times are also marked as 20:57:07, 20:58:07, 20:59:07, and 21:00:07. The test data for each round is recorded sequentially according to the operation performed at test time 20:56:07. The display module 101 can also display the wafer thickness test results, which can be displayed via a screen or touchscreen. However, this application does not specifically limit the display module 101 to display via a screen or touchscreen, and this does not affect the implementation of the embodiments of this application.
[0046] The industrial computer 102 is used to send test signals to the electrical control module 103 according to the thickness measurement time frequency; send test instructions to the electrical control module 103 according to the comparison results of the image data returned by the electrical control module 103 with the preset image data; receive and calculate the thickness test data to obtain the thickness test results, and send the thickness test results to the display module 101.
[0047] In one possible implementation, during the operation of the double-sided grinding equipment, the industrial control computer 102 can send test signals to the electrical control module 103 via Ethernet according to the input thickness measurement time frequency. The double-sided grinding equipment can be a 16B-5L double-sided grinding equipment; however, this application does not specifically limit the type of double-sided grinding equipment and does not affect the implementation of the embodiments of this application. The industrial control computer 102 can send test commands to the electrical control module 103 based on the comparison result between the image data returned by the electrical control module 103 and preset image data. Specifically, if the comparison result shows that the wafer is exposed outside the grinding pad, a test command is sent to the electrical control module 103. As an example, the image data returned by the electrical control module 103 is compared with preset image data. When the comparison result shows that the wafer is exposed outside the grinding pad during the grinding process, it indicates that the wafer is exposed and can be tested. The industrial control computer 102 sends the test command to the electrical control module 103 via Ethernet.
[0048] In one possible implementation, when the industrial control computer 102 receives the thickness test data returned by the electrical control module 103, it obtains the thickness test result by calculating the thickness test data. Specifically, it can perform logical judgments and calculations based on the thickness test data. Anomalies are displayed as NA. After removing anomalies, the average value of the valid data from each round of testing is calculated. Valid data refers to the thickness test data after removing anomalies, specifically the thickness test data where the test thickness is less than or equal to the initial thickness. The calculated average value is used as the thickness test result and sent to the display module 101. The logical judgment performed by the industrial control computer 102 based on the thickness test data pertains to the determination of anomalies, while the calculations based on the thickness test data pertain to the calculation of the average value of the valid data. As an example, if the initial thickness of the wafer is 500 micrometers, and the thickness test data received by the industrial control computer 102 is 600 micrometers, it indicates that the liquid on the wafer surface has not been completely blown away, causing the test data to include the thickness of the liquid layer. Therefore, this test data is determined to be anomaly NA.
[0049] In one possible implementation, the industrial control computer 102 is further configured to determine whether the thickness test result is within the target test thickness range. If the thickness test result is within the target test thickness range, a stop signal is sent to the grinding equipment. The target test thickness range is obtained by adding the target thickness and a preset threshold. As an example, when the target thickness is 500 micrometers and the preset threshold is ±0.5 micrometers, the target test thickness range is 499.5 micrometers to 500.5 micrometers. The thickness test result is 500 micrometers, and the industrial control computer 102 sends a stop signal to the grinding equipment, indicating that the wafer thickness has reached the target thickness.
[0050] The electrical control module 103 is used to control the photographing unit 1041 to take pictures according to the test signal, so as to obtain image data and send the image data to the industrial control computer 102; receive and control the gas control unit 1042 and the thickness measuring unit 1043 to perform tests according to the test instructions, so as to obtain thickness test data and send the thickness test data to the industrial control computer 102.
[0051] In one possible implementation, after receiving the test signal, the electrical control module 103 controls the camera unit 1041 to take a picture, obtain image data, and send the image data to the industrial computer 102 via Ethernet.
[0052] In one possible implementation, after receiving the test command from the industrial computer 102, the electrical control module 103 controls the gas control unit 1042 and the thickness measurement unit 1043 to perform the test according to the test command. Specifically, the gas control unit 1042 can be controlled to spray gas, and the thickness measurement unit 1043 can be controlled to measure thickness, thereby obtaining thickness test data and sending the thickness test data to the industrial computer 102. Controlling the gas control unit 1042 to spray gas allows the gas to blow away the polishing slurry on the surface of the wafer, exposing the wafer surface for testing. Immediately after the gas control unit 1042 blows away the polishing slurry, the thickness measurement unit 1043 performs optical thickness measurement.
[0053] The imaging unit 1041 is used to take pictures of the wafer in response to a test signal to obtain image data. In one possible implementation, the imaging unit 1041 takes pictures of the wafer in response to a test signal, and can take 30 to 40 pictures per second to obtain image data.
[0054] The gas control unit 1042 is used to inject gas onto the wafer in response to a test command. In one possible implementation, the gas injected can be 0.2 MPa compressed air or high-purity nitrogen. The gas injection head is umbrella-shaped, and the gas injection flow rate can be manually controlled by a gas valve. The gas blows away the polishing slurry on the surface of the wafer, wherein the polishing slurry can be water-soluble, and the solution on the wafer surface can be quickly removed after gas injection.
[0055] Thickness measurement unit 1043 is used to perform thickness measurement on the wafer in response to a test command. In one possible implementation, the thickness measurement unit 1043 may be a white light confocal thickness measurement probe ThinkFoucs OP1. The wafer used for thickness measurement is a white light-transmitting wafer, which may be a sapphire wafer. Optical thickness measurement of the wafer can be performed through the thickness measurement unit 1043.
[0056] The above describes a wafer thickness measurement system provided in this application embodiment. The system includes a display module, an industrial control computer, an electrical control module, and a signal acquisition module. The signal acquisition module includes an image capture unit, a gas control unit, and a thickness measurement unit. The display module acquires the initial thickness of the wafer, the target thickness of the wafer, a preset threshold, and the thickness measurement time frequency, and displays the wafer thickness test results. The industrial control computer sends a test signal to the electrical control module according to the thickness measurement time frequency. Based on the comparison between the image data returned by the electrical control module and the preset image data, it sends a test command to the electrical control module, receives and calculates the thickness test data to obtain the thickness test results, and sends the thickness test results to the display module. The electrical control module controls the image capture unit to take pictures according to the test signal to obtain image data, sends the image data to the industrial control computer, receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test command to obtain thickness test data, and sends the thickness test data to the industrial control computer. The image capture unit takes pictures of the wafer in response to the test signal to obtain image data. The gas control unit sprays gas onto the wafer in response to the test command. The thickness measurement unit performs thickness testing on the wafer in response to the test command. The thickness of the wafer can be measured directly during the double-sided grinding process, without the need to measure the thickness indirectly through other objects. This results in high measurement reliability and improved measurement accuracy.
[0057] See Figure 5 , Figure 5 A flowchart of a wafer thickness measurement method provided in this application embodiment, the method including at least the following steps:
[0058] S501: Obtain the initial thickness of the wafer, the target thickness of the wafer, the preset threshold and the thickness measurement time frequency from the display module, and display the thickness test results of the wafer.
[0059] S502: The industrial control computer sends a test signal to the electrical control module according to the thickness measurement time frequency; the industrial control computer sends a test command to the electrical control module based on the comparison result between the image data returned by the electrical control module and the preset image data; the industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module.
[0060] S503: The electrical control module controls the camera unit to take pictures according to the test signal to obtain image data and sends the image data to the industrial control computer; the electrical control module receives and controls the gas control unit and thickness measurement unit to perform tests according to the test instructions to obtain thickness test data and sends the thickness test data to the industrial control computer.
[0061] The imaging unit takes a picture of the wafer in response to the test signal to obtain image data; the gas control unit sprays gas onto the wafer in response to the test command; and the thickness measurement unit performs thickness measurement on the wafer in response to the test command.
[0062] Optionally, the industrial control computer sends a test command to the electrical control module based on the comparison result between the image data returned by the electrical control module and the preset image data, including:
[0063] When the industrial control computer determines that the wafer is exposed outside the grinding pad based on the comparison between the image data returned by the electrical control module and the preset image data, it sends a test command to the electrical control module.
[0064] Optionally, the electrical control module receives and controls the gas control unit and thickness measurement unit to perform tests according to test instructions to obtain thickness test data, and sends the thickness test data to the industrial control computer, including:
[0065] The electrical control module receives test commands and controls the gas control unit to inject gas. At the same time, it controls the thickness measurement unit to measure thickness and obtain thickness test data, which is then sent to the industrial control computer.
[0066] Optionally, the thickness measurement unit performs thickness measurement on the wafer in response to a test command, including:
[0067] The thickness measurement unit responds to test commands to perform optical thickness measurements on the wafer.
[0068] Optionally, the industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module, including:
[0069] The industrial control computer receives the thickness test data, calculates the average of the valid data to obtain the thickness test result, and sends the thickness test result to the display module. The valid data is the thickness test data where the tested thickness is less than or equal to the initial thickness.
[0070] Optionally, wafer thickness measurement methods also include:
[0071] The industrial control computer determines whether the thickness test result is within the target test thickness range. If the thickness test result is within the target test thickness range, it sends a stop signal to the grinding equipment. The target test thickness range is obtained by adding the target thickness and a preset threshold.
[0072] This application provides a wafer thickness measurement method applied to a wafer thickness measurement system. The wafer thickness measurement system includes a display module, an industrial control computer, an electrical control module, and a signal acquisition module. The signal acquisition module includes an image acquisition unit, a gas control unit, and a thickness measurement unit. The display module acquires the initial thickness of the wafer, the target thickness of the wafer, a preset threshold, and the thickness measurement time frequency, and displays the wafer thickness test results. The industrial control computer sends test signals to the electrical control module according to the thickness measurement time frequency. Based on the comparison between the image data returned by the electrical control module and the preset image data, the industrial control computer sends test commands to the electrical control module. The industrial control computer receives and calculates the thickness test data to obtain the thickness test results, and sends the thickness test results to the display module. The electrical control module controls the imaging unit to take pictures based on the test signal to obtain image data, and then sends the image data to the industrial control computer. The electrical control module also receives and controls the gas control unit and thickness measurement unit to perform tests according to the test commands to obtain thickness test data, which is then sent to the industrial control computer. The imaging unit takes pictures of the wafer in response to the test signal to obtain image data; the gas control unit sprays gas onto the wafer in response to the test commands; and the thickness measurement unit performs thickness tests on the wafer in response to the test commands. During double-sided grinding, wafer thickness can be measured directly, eliminating the need for indirect thickness measurement through other objects, resulting in high reliability and improved measurement accuracy.
[0073] In the embodiments of this application, the terms "first" and "second" (if they exist) are used only as name identifiers and do not represent the order of first and second.
[0074] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general-purpose hardware platform. Based on this understanding, the technical solution of this application can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as a read-only memory (ROM) / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or some parts of the embodiments of this application.
[0075] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for the device embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiments. The device embodiments described above are merely illustrative, and the units described as separate components may or may not be physically separate. The components indicated as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment solution according to actual needs. Those skilled in the art can understand and implement this without creative effort.
[0076] The above description is merely one specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A wafer thickness measurement system, characterized in that, The system includes a display module, an industrial computer, an electrical control module, and a signal acquisition module; the signal acquisition module includes an image acquisition unit, a gas control unit, and a thickness measurement unit. The display module is used to acquire the initial thickness of the wafer, the target thickness of the wafer, the preset threshold and the thickness measurement time frequency, and to display the thickness test results of the wafer. The industrial control computer is used to send test signals to the electrical control module according to the thickness measurement time frequency; Based on the comparison result between the image data returned by the electrical control module and the preset image data, a test command is sent to the electrical control module; the thickness test data is received and calculated to obtain the thickness test result, and the thickness test result is sent to the display module. The electrical control module is used to control the camera unit to take pictures according to the test signal, so as to obtain the image data and send the image data to the industrial control computer; The system receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test instructions, so as to obtain the thickness test data and send the thickness test data to the industrial control computer. The imaging unit is used to take a picture of the wafer in response to the test signal and obtain the image data; The gas control unit is configured to spray gas onto the wafer in response to the test command to remove the polishing slurry from the wafer surface. The thickness measurement unit is used to perform thickness testing on the wafer in response to the test command; The electrical control module is specifically used to receive the test command, control the gas control unit to perform gas injection through the test command, and control the thickness measurement unit to perform thickness measurement to obtain thickness test data through the test command, and send the thickness test data to the industrial control computer. The industrial control computer is specifically used to receive the thickness test data, calculate the average value of the effective data of the thickness test data to obtain the thickness test result, and send the thickness test result to the display module. The effective data is the thickness test data where the test thickness is less than or equal to the initial thickness. Specifically, the industrial control computer is used to send a test command to the electrical control module when the comparison result between the image data returned by the electrical control module and the preset image data indicates that the wafer is exposed outside the grinding pad.
2. The system according to claim 1, characterized in that, The thickness measuring unit is specifically used for: The thickness measurement unit is used to perform optical thickness testing on the wafer in response to the test command.
3. The system according to any one of claims 1 to 2, characterized in that, The industrial control computer is also used to determine whether the thickness test result is within the target test thickness range. If the thickness test result is within the target test thickness range, a stop signal is sent to the grinding equipment. The target test thickness range is obtained by adding the target thickness and the preset threshold.
4. A method for measuring wafer thickness, characterized in that, An application is made in a wafer thickness measurement system, the wafer thickness measurement system including a display module, an industrial control computer, an electrical control module, and a signal acquisition module; the signal acquisition module includes an image capture unit, a gas control unit, and a thickness measurement unit, and the method includes: The display module acquires the initial thickness of the wafer, the target thickness of the wafer, the preset threshold, and the thickness measurement time frequency, and displays the thickness test results of the wafer. The industrial control computer sends a test signal to the electrical control module according to the thickness measurement time frequency; the industrial control computer sends a test command to the electrical control module according to the comparison result of the image data returned by the electrical control module and the preset image data; the industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module. The electrical control module controls the imaging unit to take pictures according to the test signal to obtain the image data, and sends the image data to the industrial control computer; the electrical control module receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test command to obtain the thickness test data, and sends the thickness test data to the industrial control computer; the imaging unit takes pictures of the wafer in response to the test signal to obtain the image data; the gas control unit sprays gas onto the wafer in response to the test command; the thickness measurement unit performs thickness tests on the wafer in response to the test command. The electrical control module receives and controls the gas control unit and the thickness measurement unit to perform tests according to the test instructions to obtain thickness test data, and sends the thickness test data to the industrial control computer, including: The electrical control module receives the test command and controls the gas control unit to spray gas to remove the polishing slurry from the wafer surface. At the same time, it controls the thickness measurement unit to measure the thickness to obtain thickness test data and sends the thickness test data to the industrial control computer. The industrial control computer receives and calculates the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module, including: The industrial control computer receives the thickness test data, calculates the average value of the valid data of the thickness test data to obtain the thickness test result, and sends the thickness test result to the display module. The valid data is the thickness test data where the test thickness is less than or equal to the initial thickness. The industrial control computer sends a test command to the electrical control module based on the comparison result between the image data returned by the electrical control module and the preset image data, including: When the industrial control computer determines that the wafer is exposed outside the grinding pad based on the comparison result between the image data returned by the electrical control module and the preset image data, it sends a test command to the electrical control module.
5. The method according to claim 4, characterized in that, The thickness measurement unit responds to the test command to perform a thickness test on the wafer, including: The thickness measurement unit performs optical thickness testing on the wafer in response to the test command.