An intelligent detection method for wafer surface defects based on visual analysis

Abstract

The invention discloses an intelligent detection method for wafer surface defects based on visual analysis, relates to the field of wafers, solves the current problems of limitations in wafer detection content and inaccurate detection, and the method comprises: a detection terminal imports standard specification data of a wafer to be tested, and the standard specification data is sent to a specification detection module via a server; the specification detection module detects the product specifications of the wafer to be tested; a comprehensive sorting module sorts the wafer to be tested according to the specification detection results of the wafer to be tested; a defect detection module detects surface defects of the wafer to be tested, and obtains surface defect detection results of the wafer to be tested; the comprehensive sorting module also sorts the wafer to be tested according to the surface defect detection results of the wafer to be tested, and transports the surface defect detection of the wafer to be tested to a waste area, a product storage area or a wafer processing link. The invention realizes accurate detection of wafer surface defects based on visual analysis.

Description

Technical Field

[0001] The present invention belongs to the field of wafers and relates to defect detection technology, in particular to an intelligent detection method for wafer surface defects based on visual analysis. Background Art

[0002] Wafer refers to the silicon wafer used to make silicon semiconductor circuits. Its original material is silicon. High-purity polycrystalline silicon is dissolved and doped with silicon crystal seeds, and then slowly pulled out to form cylindrical single crystal silicon. After grinding, polishing and slicing, the silicon crystal rod forms a silicon wafer, that is, a wafer. Domestic wafer production lines are mainly 8-inch and 12-inch;

[0003] At present, when performing surface defect detection on wafers, the detection content is usually limited to the thickness and specifications of the wafers, and no in-depth detection of the wafers is performed. For example, although there are some equipment and mechanisms for wafer surface defect detection, these equipment and mechanisms still have problems such as inaccurate detection;

[0004] To this end, we propose an intelligent detection method for wafer surface defects based on visual analysis. Summary of the invention

[0005] In view of the deficiencies in the prior art, the object of the present invention is to provide an intelligent detection method for wafer surface defects based on visual analysis.

[0006] The technical problem to be solved by the present invention is: how to accurately detect wafer surface defects based on visual analysis.

[0007] In order to achieve the above object, the present invention adopts the following technical solution: a wafer surface defect intelligent detection method based on visual analysis, the method comprising:

[0008] Step S101, the detection terminal imports the standard specification data of the wafer to be tested, and the standard specification data is sent to the specification detection module via the server;

[0009] Step S102, the specification detection module detects the product specifications of the wafer to be tested, and obtains the specification detection result of the wafer to be tested and sends it to the comprehensive sorting module via the server;

[0010] Step S103, the comprehensive sorting module sorts the wafers to be tested according to the specification detection results of the wafers to be tested, and transports the wafers to be tested to the waste area, wafer processing link or defect detection module;

[0011] Step S104, the defect detection module detects surface defects of the wafer to be tested, and the surface defect detection result of the wafer to be tested is sent to the comprehensive sorting module via the server;

[0012] Step S105, the comprehensive sorting module further sorts the wafers to be tested according to the surface defect detection results of the wafers to be tested, and transfers the surface defect detection of the wafers to be tested to the waste area, product storage area or wafer processing link.

[0013] Furthermore, the standard specification data includes a specification wafer diameter and a specification wafer thickness of the wafer to be tested.

[0014] Furthermore, in step S102, the detection process of the specification detection module is as follows:

[0015] Using the geometric center of the wafer to be tested as the rotation axis center of the wafer to be tested, controlling the clamping device to fix the wafer to be tested between the upper clamping head and the lower clamping head;

[0016] The upper clamping head and the lower clamping head rotate clockwise and counterclockwise at the same angular velocity, respectively. At the same time, the diameter measuring unit and the thickness measuring unit collect the actual wafer diameter and the actual wafer thickness of the wafer to be measured;

[0017] Compare the measured wafer diameter of the wafer to be tested with the standard diameter range, and compare the measured wafer thickness of the wafer to be tested with the standard thickness range;

[0018] If any set of data of the measured wafer diameter and the measured wafer thickness of the wafer to be tested does not belong to the corresponding standard diameter range and standard thickness range, the wafer to be tested is marked as a defective wafer;

[0019] If the measured wafer diameter and the measured wafer thickness of the wafer to be measured both belong to the corresponding standard diameter range and standard thickness range, the edge roundness and surface roughness of the wafer to be measured are calculated;

[0020] Compare the edge roundness and surface roughness of the wafer to be tested with the specification detection threshold;

[0021] If the edge roundness and surface roughness of the wafer to be tested are both less than or equal to the first specification detection threshold, the specification detection result of the wafer to be tested is determined to be qualified;

[0022] If any value of the edge roundness or surface undulation of the wafer to be tested is greater than the first specification detection threshold and less than or equal to the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be reprocessing;

[0023] If any value of the edge roundness or the surface undulation of the wafer to be tested is greater than the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be unqualified.

[0024] Furthermore, the values ​​of the first specification detection threshold and the second specification detection threshold are both greater than zero, and the first specification detection threshold is less than the second specification detection threshold.

[0025] Furthermore, in step S103, the sorting process of the comprehensive sorting module includes:

[0026] If the specification test result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area;

[0027] If the specification test result of the wafer to be tested is reprocessing, the wafer to be tested will be transferred to the wafer processing link for reprocessing;

[0028] If the specification inspection result of the wafer to be tested is qualified, the wafer to be tested is transferred to the defect inspection module.

[0029] Furthermore, in step S104, the detection process of the defect detection module is as follows:

[0030] Place the wafer to be tested in the groove of the testing platform and cover it with a limiting glass slide;

[0031] In an inspection environment without interference from external light sources, the defect inspection lamp illuminates the horizontally placed wafer to be inspected, and the light-receiving surface displays the horizontal illumination image of the wafer to be inspected. Then, the defect inspection lamp illuminates the tilted wafer to be inspected, and the light-receiving surface displays the oblique illumination image of the wafer to be inspected.

[0032] The horizontal illumination imaging pictures and the oblique illumination imaging pictures of the wafer to be tested are collected by a high-definition camera, and the size and number of imaging defects in the pictures are counted;

[0033] Calculate the surface defect value of the wafer to be tested;

[0034] Compare the surface defect value of the wafer to be tested with the surface defect threshold:

[0035] If the surface defect value of the wafer to be tested is less than or equal to the first surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be qualified;

[0036] If the surface defect value of the wafer to be tested is greater than the first surface defect threshold and less than or equal to the second surface defect threshold, then the surface defect detection result of the wafer to be tested is determined to be reprocessing;

[0037] If the surface defect value of the wafer to be tested is greater than the second surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be unqualified;

[0038] The values ​​of the first surface defect threshold and the second surface defect threshold are both greater than zero, and the first surface defect threshold is less than the second surface defect threshold.

[0039] Furthermore, the surface defects of the wafer to be tested will display shadow points or shadow blocks on the light-receiving surface after being illuminated by the defect detection light. The color of the shadow points or shadow blocks is different from the color of the light-receiving surface directly illuminated by the defect detection light. The size of the imaged defect is the area of ​​the shadow point or shadow block, and the number of imaged defects is the number of shadow points or shadow blocks.

[0040] Furthermore, in step S105, the sorting process of the comprehensive sorting module further includes:

[0041] If the surface defect detection result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area;

[0042] If the surface defect detection result of the wafer to be tested is reprocessing, the wafer to be tested is transferred to the wafer processing link for reprocessing;

[0043] If the surface defect detection result of the wafer to be tested is qualified, the wafer to be tested will be transported to the product storage area.

[0044] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0045] The present invention uses a detection terminal to import standard specification data of a wafer to be tested and sends it to a specification detection module, and then uses the specification detection module to detect the product specifications of the wafer to be tested, and obtains the specification detection results of the wafer to be tested and sends them to a comprehensive sorting module. The comprehensive sorting module sorts the wafer to be tested according to the specification detection results of the wafer to be tested, thereby transferring the wafer to be tested to a waste area, a wafer processing link or a defect detection module. If the wafer to be tested is transferred to the defect detection module, the defect detection module is used to detect surface defects of the wafer to be tested, and the surface defect detection results of the wafer to be tested are sent to the comprehensive sorting module. The wafer to be tested is sorted again by the comprehensive sorting module according to the surface defect detection results of the wafer to be tested, and finally the surface defect detection of the wafer to be tested is transferred to a waste area, a product storage area or a wafer processing link. The present invention realizes accurate detection of wafer surface defects based on visual analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0047] Figure 1 is a flow chart of the method of the present invention;

[0048] Figure 2 is a system connection diagram of the present invention;

[0049] Figure 3 It is a schematic diagram of the principle of the specification detection module in the present invention;

[0050] Figure 4It is a schematic diagram of the principle of the defect detection module in the present invention;

[0051] Figure 5 It is a schematic diagram of the structure of the electronic device in the present invention. DETAILED DESCRIPTION

[0052] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Embodiment 1;

[0054] See also Figure 1 The present invention provides a technical solution: a wafer surface defect intelligent detection method based on visual analysis, the method comprising:

[0055] Step S101, the detection terminal imports the standard specification data of the wafer to be tested, and uploads the standard specification data of the wafer to be tested to the server, and the server sends the standard specification data of the wafer to be tested to the specification detection module;

[0056] Step S102, the specification detection module is used to detect the product specifications of the wafer to be tested, and the geometric center of the wafer to be tested is used as the rotation axis center of the wafer to be tested, and the clamping device is controlled to fix the wafer to be tested between the upper clamping head and the lower clamping head. The upper clamping head and the lower clamping head rotate clockwise and counterclockwise at the same angular velocity respectively. At the same time, the diameter measurement unit and the thickness measurement unit collect the measured wafer diameter and the measured wafer thickness of the wafer to be tested, and compare the measured wafer diameter of the wafer to be tested with the standard diameter range, and at the same time, compare the measured wafer thickness of the wafer to be tested with the standard thickness range. If any set of data of the measured wafer diameter and the measured wafer thickness of the wafer to be tested does not belong to the corresponding standard diameter range and standard thickness range, the wafer to be tested is marked as a defective wafer. If the measured wafer diameter and the measured wafer thickness of the wafer to be tested both belong to the corresponding The standard diameter interval and the standard thickness interval are used to calculate the edge roundness and surface undulation of the wafer to be tested according to the formula, and the edge roundness and surface undulation of the wafer to be tested are compared with the specification detection threshold. If the edge roundness and surface undulation of the wafer to be tested are both less than or equal to the first specification detection threshold, the specification detection result of the wafer to be tested is determined to be qualified. If any value of the edge roundness or surface undulation of the wafer to be tested is greater than the first specification detection threshold and less than or equal to the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be reprocessed. If any value of the edge roundness or surface undulation of the wafer to be tested is greater than the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be unqualified. The specification detection module sends the specification detection result of the wafer to be tested to the server, and the server sends the specification detection result of the wafer to be tested to the comprehensive sorting module;

[0057] Step S103, the comprehensive sorting module sorts the wafers to be tested according to the specification detection results of the wafers to be tested. If the specification detection result of the wafers to be tested is unqualified, the wafers to be tested are transported to the waste area. If the specification detection result of the wafers to be tested is reprocessed, the wafers to be tested are transported to the wafer processing link for reprocessing. If the specification detection result of the wafers to be tested is qualified, the wafers to be tested are transported to the defect detection module;

[0058] Step S104, the defect detection module detects surface defects of the wafer to be tested, places the wafer to be tested in the groove of the detection platform and covers it with a limiting glass slide, and in a detection environment without interference from external light sources, illuminates the horizontally placed wafer to be tested with a defect detection lamp, and the light-bearing surface displays the horizontal illumination image of the wafer to be tested, and then illuminates the tilted wafer to be tested with a defect detection lamp, and the light-bearing surface displays the oblique illumination image of the wafer to be tested, and collects horizontal illumination imaging images and oblique illumination imaging images of the wafer to be tested through a high-definition camera, and counts the size and number of imaging defects in the images, calculates the surface defect value of the wafer to be tested, and calculates the value of the surface defect of the wafer to be tested. The surface defect value is compared with the surface defect threshold. If the surface defect value of the wafer to be tested is less than or equal to the first surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be qualified. If the surface defect value of the wafer to be tested is greater than the first surface defect threshold and less than or equal to the second surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be reprocessed. If the surface defect value of the wafer to be tested is greater than the second surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be unqualified. The defect detection module sends the surface defect detection result of the wafer to be tested to the server, and the server sends the surface defect detection result of the wafer to be tested to the comprehensive sorting module;

[0059] Step S105, the comprehensive sorting module also sorts the wafers to be tested according to the surface defect detection result of the wafers to be tested. If the surface defect detection result of the wafers to be tested is unqualified, the wafers to be tested are transferred to the scrap area. If the surface defect detection result of the wafers to be tested is for reprocessing, the wafers to be tested are transferred to the wafer processing link for reprocessing. If the surface defect detection result of the wafers to be tested is qualified, the wafers to be tested are transferred to the product storage area.

[0060] In this embodiment, if Figure 2-Figure 4 As shown, the method specifically involves a server, which is connected to a detection terminal, a specification detection module, a defect detection module and a comprehensive sorting module;

[0061] In this embodiment, the wafer to be tested is a cylinder with a uniform thickness at all places. The detection terminal is used to import the standard specification data of the wafer to be tested, and the standard specification data includes the standard wafer diameter and the standard wafer thickness of the wafer to be tested. The detection terminal uploads the standard specification data of the wafer to be tested to the server, and the server sends the standard specification data of the wafer to be tested to the specification detection module;

[0062] like Figure 3 As shown, the specification detection module is used to detect the product specifications of the wafer to be tested. The detection process is as follows:

[0063] The geometric center of the wafer to be tested is used as the rotation axis center of the wafer to be tested, and the clamping device is controlled to fix the wafer to be tested between the upper clamping head and the lower clamping head, wherein the surfaces of the upper clamping head and the lower clamping head are both covered with anti-slip materials to prevent the wafer to be tested from loosening or displacement during the test;

[0064] The upper clamping head and the lower clamping head rotate clockwise and counterclockwise at the same angular velocity, respectively. At the same time, the diameter measuring unit and the thickness measuring unit collect the measured wafer diameter SZi and the measured wafer thickness SHi of the wafer to be measured. i is the measured data sequence number, and the upper limit value of i is n. The value of n is equal to the number of groups of measured data collected when the wafer to be measured rotates one circle. For example, the wafer to be measured rotates one circle at an angular velocity of 3° / s driven by the clamping device, and the measured data of the gold source to be measured is collected once per second, then the upper limit value n of i is 120;

[0065] Compare the measured wafer diameter of the wafer to be tested with the standard diameter range, and compare the measured wafer thickness of the wafer to be tested with the standard thickness range:

[0066] If any set of data of the measured wafer diameter and the measured wafer thickness of the wafer to be tested does not belong to the corresponding standard diameter range and standard thickness range, the wafer to be tested is marked as a defective wafer;

[0067] Among them, the standard diameter interval and the standard thickness interval are set based on the specification wafer diameter and specification wafer thickness of the measured wafer, respectively, the standard diameter interval∈(specification wafer diameter×97%, specification wafer diameter×103%), the standard thickness interval∈(specification wafer thickness×97%, specification wafer thickness×103%);

[0068] If the measured wafer diameter and the measured wafer thickness of the wafer to be measured belong to the corresponding standard diameter range and standard thickness range, the edge roundness BY and the surface roughness BM of the wafer to be measured are calculated according to the formula, and the specific formula is as follows:

[0069]

[0070] Among them, MZ is the maximum value of the measured wafer diameter of the wafer to be tested, and BH is the standard wafer thickness of the wafer to be tested. It can be understood that the smaller the value of the edge roundness is, the closer the cross section of the wafer to be tested is to the theoretical circle, and the smaller the value of the surface undulation is, the flatter the surface of the wafer to be tested is;

[0071] Compare the edge roundness and surface roughness of the wafer to be tested with the specification detection threshold:

[0072] If the edge roundness and surface roughness of the wafer to be tested are both less than or equal to the first specification detection threshold, the specification detection result of the wafer to be tested is determined to be qualified;

[0073] If any value of the edge roundness or surface undulation of the wafer to be tested is greater than the first specification detection threshold and less than or equal to the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be reprocessing;

[0074] If any value of the edge roundness or the surface roughness of the wafer to be tested is greater than the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be unqualified;

[0075] Wherein, the values ​​of the first specification detection threshold and the second specification detection threshold are both greater than zero, and the first specification detection threshold is less than the second specification detection threshold;

[0076] The specification detection module sends the specification detection result of the wafer to be tested to the server, and the server sends the specification detection result of the wafer to be tested to the comprehensive sorting module;

[0077] The comprehensive sorting module is used to sort the wafers to be tested according to the specification test results of the wafers to be tested. The sorting process includes:

[0078] If the specification test result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area;

[0079] If the specification test result of the wafer to be tested is reprocessing, the wafer to be tested will be transferred to the wafer processing link for reprocessing;

[0080] If the specification test result of the wafer to be tested is qualified, the wafer to be tested is transferred to the defect detection module;

[0081] The defect detection module is used to detect surface defects of the wafer to be tested. The detection process is as follows:

[0082] like Figure 4 As shown, the wafer to be tested is placed in the groove of the testing platform and covered with a limiting glass. It can be understood that the limiting glass ensures that the wafer to be tested and the testing platform are relatively stationary during the test without damaging the surface of the wafer to be tested;

[0083] In a detection environment without interference from external light sources, the defect detection lamp is used to illuminate the horizontally placed wafer to be tested, and the light-receiving surface displays the horizontal illumination image of the wafer to be tested. Then, the defect detection lamp is used to illuminate the tilted wafer to be tested, and the light-receiving surface displays the oblique illumination image of the wafer to be tested. In this embodiment, when the wafer to be tested is placed horizontally, the wafer to be tested and the test surface are parallel to each other. When the wafer to be tested is placed tilted, the angle between the wafer to be tested and the test surface is 45°. By irradiating the wafer to be tested at different angles, defects missed due to the single illumination angle of the defect detection lamp can be avoided.

[0084] The horizontal illumination imaging pictures and the oblique illumination imaging pictures of the wafer to be tested are collected by a high-definition camera, and the imaging defect size XDp and the imaging defect number XS in the pictures are counted. It should be specifically stated that the surface defects of the wafer to be tested are displayed as shadow points or shadow blocks on the light-bearing surface after being illuminated by the defect detection light. The color of the shadow point or shadow block is different from the color of the defect detection light directly irradiating the light-bearing surface. The imaging defect size is the area of ​​the shadow point or shadow block, the imaging defect number is the number of the shadow points or shadow blocks, p is the number of the imaging defect, the upper limit value of p is m, and the value of m is equal to the value of the imaging defect number XS;

[0085] The surface defect value BX of the wafer to be tested is calculated according to the formula. The specific formula is as follows:

[0086] Where V is the standard wafer volume of the wafer to be tested, V = standard wafer thickness × (standard wafer diameter / 2) 2 ×π;

[0087] Compare the surface defect value of the wafer to be tested with the surface defect threshold:

[0088] If the surface defect value of the wafer to be tested is less than or equal to the first surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be qualified;

[0089] If the surface defect value of the wafer to be tested is greater than the first surface defect threshold and less than or equal to the second surface defect threshold, then the surface defect detection result of the wafer to be tested is determined to be reprocessing;

[0090] If the surface defect value of the wafer to be tested is greater than the second surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be unqualified;

[0091] Wherein, the values ​​of the first surface defect threshold and the second surface defect threshold are both greater than zero, and the first surface defect threshold is less than the second surface defect threshold;

[0092] The defect detection module sends the surface defect detection result of the wafer to be tested to the server, and the server sends the surface defect detection result of the wafer to be tested to the comprehensive sorting module;

[0093] The comprehensive sorting module is also used to sort the wafers to be tested according to the surface defect detection results of the wafers to be tested. The sorting process is as follows:

[0094] If the surface defect detection result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area;

[0095] If the surface defect detection result of the wafer to be tested is reprocessing, the wafer to be tested is transferred to the wafer processing link for reprocessing;

[0096] If the surface defect detection result of the wafer to be tested is qualified, the wafer to be tested is transported to the product storage area;

[0097] In this application, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficient and the proportional coefficient can be determined as long as it does not affect the proportional relationship between the parameter and the result value.

[0098] Figure 5 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 5 As shown, the electronic device may include: a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus. The processor can call the logic instructions in the memory to execute an intelligent wafer surface defect detection method based on visual analysis, which includes: the detection terminal imports the standard specification data of the wafer to be tested, and the standard specification data is sent to the specification detection module via the server; the specification detection module detects the product specifications of the wafer to be tested, and the specification detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module sorts the wafer to be tested according to the specification detection results of the wafer to be tested, and transfers the wafer to be tested to the waste area, wafer processing link or defect detection module; the defect detection module detects the surface defects of the wafer to be tested, and the surface defect detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module also sorts the wafer to be tested according to the surface defect detection results of the wafer to be tested, and transfers the surface defect detection of the wafer to be tested to the waste area, product storage area or wafer processing link.

[0099] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art, and the computer software product is stored in a storage medium, including several instructions to enable an electronic device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk.

[0100] On the other hand, the present application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by the computer, the computer can execute a wafer surface defect intelligent detection method based on visual analysis provided by the above methods, the method including: the detection terminal imports standard specification data of the wafer to be tested, and the standard specification data is sent to the specification detection module via the server; the specification detection module detects the product specifications of the wafer to be tested, and the obtained specification detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module sorts the wafer to be tested according to the specification detection results of the wafer to be tested, and transfers the wafer to be tested to the waste area, wafer processing link or defect detection module; the defect detection module detects surface defects of the wafer to be tested, and the surface defect detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module also sorts the wafer to be tested according to the surface defect detection results of the wafer to be tested, and transfers the surface defect detection of the wafer to be tested to the waste area, product storage area or wafer processing link.

[0101] On the other hand, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the above-mentioned intelligent detection method for wafer surface defects based on visual analysis, the method comprising: the detection terminal imports standard specification data of the wafer to be tested, and the standard specification data is sent to the specification detection module via the server; the specification detection module detects the product specifications of the wafer to be tested, and the obtained specification detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module sorts the wafer to be tested according to the specification detection results of the wafer to be tested, and transfers the wafer to be tested to the waste area, wafer processing link or defect detection module; the defect detection module detects surface defects of the wafer to be tested, and the obtained surface defect detection results of the wafer to be tested are sent to the comprehensive sorting module via the server; the comprehensive sorting module also sorts the wafer to be tested according to the surface defect detection results of the wafer to be tested, and transfers the surface defect detection of the wafer to be tested to the waste area, product storage area or wafer processing link.

[0102] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0103] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for an electronic device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A wafer surface defect intelligent detection method based on visual analysis, characterized in that: Methods include: Step S101, the detection terminal imports the standard specification data of the wafer to be tested, and the standard specification data is sent to the specification detection module via the server; Step S102, the specification detection module detects the product specifications of the wafer to be tested, and obtains the specification detection result of the wafer to be tested and sends it to the comprehensive sorting module via the server; In step S102, the detection process of the specification detection module is as follows: Using the geometric center of the wafer to be tested as the rotation axis center of the wafer to be tested, controlling the clamping device to fix the wafer to be tested between the upper clamping head and the lower clamping head; The upper clamping head and the lower clamping head rotate clockwise and counterclockwise at the same angular velocity, respectively. At the same time, the diameter measuring unit and the thickness measuring unit collect the measured wafer diameter SZi and the measured wafer thickness SHi of the wafer to be measured, where i is the measured data serial number, and the upper limit of i is n, and the value of n is equal to the number of groups of measured data collected when the wafer to be measured rotates one circle; Compare the measured wafer diameter of the wafer to be tested with the standard diameter range, and compare the measured wafer thickness of the wafer to be tested with the standard thickness range; If any set of data of the measured wafer diameter and the measured wafer thickness of the wafer to be tested does not belong to the corresponding standard diameter range and standard thickness range, the wafer to be tested is marked as a defective wafer; If the measured wafer diameter and the measured wafer thickness of the wafer to be measured belong to the corresponding standard diameter range and standard thickness range, the edge roundness BY and the surface roughness BM of the wafer to be measured are calculated according to the formula, and the specific formula is as follows: ; ; Wherein, MZ is the maximum value of the measured wafer diameter of the wafer to be tested, and BH is the standard wafer thickness of the wafer to be tested; Compare the edge roundness and surface roughness of the wafer to be tested with the specification detection threshold; If the edge roundness and surface roughness of the wafer to be tested are both less than or equal to the first specification detection threshold, the specification detection result of the wafer to be tested is determined to be qualified; If any value of the edge roundness or surface undulation of the wafer to be tested is greater than the first specification detection threshold and less than or equal to the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be reprocessing; If any value of the edge roundness or surface roughness of the wafer to be tested is greater than the second specification detection threshold, the specification detection result of the wafer to be tested is determined to be unqualified; Step S103, the comprehensive sorting module sorts the wafers to be tested according to the specification detection results of the wafers to be tested, and transports the wafers to be tested to the waste area, wafer processing link or defect detection module; In step S103, the sorting process of the comprehensive sorting module includes: If the specification test result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area; If the specification test result of the wafer to be tested is reprocessing, the wafer to be tested will be transferred to the wafer processing link for reprocessing; If the specification test result of the wafer to be tested is qualified, the wafer to be tested is transferred to the defect detection module; Step S104, the defect detection module detects surface defects of the wafer to be tested, and the surface defect detection result of the wafer to be tested is sent to the comprehensive sorting module via the server; In step S104, the detection process of the defect detection module is as follows: Place the wafer to be tested in the groove of the testing platform and cover it with a limiting glass slide; In an inspection environment without interference from external light sources, the defect inspection lamp illuminates the horizontally placed wafer to be inspected, and the light-receiving surface displays the horizontal illumination image of the wafer to be inspected. Then, the defect inspection lamp illuminates the tilted wafer to be inspected, and the light-receiving surface displays the oblique illumination image of the wafer to be inspected. The horizontal illumination imaging pictures and the oblique illumination imaging pictures of the wafer to be tested are collected by a high-definition camera, and the imaging defect size XDp and the number of imaging defects in the pictures are counted, where p is the number of the imaging defect, the upper limit of p is m, and the value of m is equal to the value of the number of imaging defects; The surface defect value BX of the wafer to be tested is calculated according to the formula. The specific formula is as follows: ; Where V is the standard wafer volume of the wafer to be tested, V = standard wafer thickness × (standard wafer diameter / 2) 2 ×π; Compare the surface defect value of the wafer to be tested with the surface defect threshold: If the surface defect value of the wafer to be tested is less than or equal to the first surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be qualified; If the surface defect value of the wafer to be tested is greater than the first surface defect threshold and less than or equal to the second surface defect threshold, then the surface defect detection result of the wafer to be tested is determined to be reprocessing; If the surface defect value of the wafer to be tested is greater than the second surface defect threshold, the surface defect detection result of the wafer to be tested is determined to be unqualified; Wherein, the values ​​of the first surface defect threshold and the second surface defect threshold are both greater than zero, and the first surface defect threshold is less than the second surface defect threshold; Step S105, the comprehensive sorting module further sorts the wafers to be tested according to the surface defect detection results of the wafers to be tested, and transports the surface defect detection of the wafers to be tested to the waste area, product storage area or wafer processing link; In step S105, the sorting process of the comprehensive sorting module further includes: If the surface defect detection result of the wafer to be tested is unqualified, the wafer to be tested will be transferred to the waste area; If the surface defect detection result of the wafer to be tested is reprocessing, the wafer to be tested is transferred to the wafer processing link for reprocessing; If the surface defect detection result of the wafer to be tested is qualified, the wafer to be tested will be transported to the product storage area.

2. According to claim 1, a wafer surface defect intelligent detection method based on visual analysis is characterized in that: The standard specification data includes the specification wafer diameter and the specification wafer thickness of the wafer to be tested.

3. The method for intelligent detection of wafer surface defects based on visual analysis according to claim 1, characterized in that: The values ​​of the first specification detection threshold and the second specification detection threshold are both greater than zero, and the first specification detection threshold is less than the second specification detection threshold.

4. The method for intelligent detection of wafer surface defects based on visual analysis according to claim 1, characterized in that: The surface defects of the wafer to be tested will appear as shadow points or shadow blocks on the light-receiving surface after being illuminated by the defect detection light. The color of the shadow points or shadow blocks is different from the color of the light-receiving surface directly illuminated by the defect detection light. The size of the imaged defect is the area of ​​the shadow point or shadow block, and the number of imaged defects is the number of shadow points or shadow blocks.

5. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the method according to any one of claims 1 to 4 are executed.

6. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are executed.

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