Wafer positioning and defect detection method and device and medium

Abstract

The invention discloses a wafer positioning and defect detection method, and relates to the field of wafer defect detection. An existing detection method has the problem that defect detection accuracy and time cost cannot be considered at the same time. The detection method comprises the following steps: scanning and recording the position of a wafer to be detected, taking out the wafer according to the position, carrying out first-stage defect detection after eccentric correction and angle positioning, and recording defect information; if high-magnification reinspection is needed, imaging analysis is carried out on the first detection surface, the second detection surface and the surface of the wafer according to defect positions, and information is updated; and after the detection is completed, the wafer is stored at a designated position. Scanning and storing have multiple modes, and detection can be automatically executed through a computer program. The surface of the wafer is modeled and partitioned, two-dimensional regions are divided, and detection results are marked and recorded. According to the invention, primary detection and high-magnification redetection are combined, the defect detection accuracy and detection efficiency are considered, automatic detection can be realized, a production line can be adapted, and accurate and consistent detection is ensured through multiple positioning modes.

Description

Technical Field

[0001] The present invention relates to the field of wafer defect detection, and in particular to a wafer defect optical detection method. Background Art

[0002] Scratches, particle contamination, abnormal crystal structure and other defects on the wafer surface may cause circuit short circuit, open circuit or deterioration of electrical performance; micro cracks on the wafer surface will also form stress concentration points, increasing the risk of fragmentation. Once defects occur on the wafer surface, they will seriously interfere with the subsequent process and affect the final yield.

[0003] The speed and accuracy of wafer defect detection are directly related to the efficiency and quality of wafer production. Early wafer defect detection can also reduce ineffective processing in subsequent processes and significantly reduce material loss.

[0004] The current wafer defect detection method requires manual transfer of the wafer to be inspected during the primary and secondary inspections. The transfer process will cause the wafer position to deviate from the preset inspection position, which will lead to large errors in subsequent defect detection and affect the judgment of wafer defects. Summary of the invention

[0005] To solve the above problems, the present invention provides a wafer positioning and defect detection method, which has the following process: S1, scan and record the positions of all wafers to be inspected; S2, taking out the wafer to be inspected according to the position of the wafer; S3, correcting the eccentricity and angular positioning of the wafer; S4, performing a primary defect detection on the wafer and recording defect information, wherein the defect information includes a defect location and a defect type; S5, if the wafer needs high-magnification re-inspection, find the recorded defect position through angle positioning, and re-inspect the defect position at a high magnification. During the high-magnification re-inspection, an imaging device is used to image the defect position on the first detection surface, the wafer surface, and the second detection surface respectively. The first detection surface is higher than the wafer surface, and the second detection surface is lower than the wafer surface. The three plane imaging analyses are combined to update the defect information; if the wafer does not need high-magnification re-inspection, proceed directly to the next step; S6, complete wafer defect detection and record the detection results.

[0006] High-magnification re-inspection can achieve accurate detection of defects without misjudgment or missed judgment. In addition, this detection method only re-inspects the defect location and does not need to maintain a high magnification, which improves the efficiency of wafer defect detection.

[0007] Eccentricity correction can ensure that the wafer is quickly positioned to the initial point of detection during inspection, which is convenient for subsequent angle positioning and defect position recording. Angle positioning is achieved by finding marks on the wafer.

[0008] Based on the above scheme, the modes for scanning and recording the wafer position include a traversal mode and a selection mode; In the traversal mode, all wafers in the wafer box are inspected in sequence; In the selection mode, the number and position of wafers to be inspected in the wafer box are manually selected according to inspection requirements.

[0009] The inspector can set up to inspect only designated wafers or all wafers stored in a wafer box as needed. The wafer storage area here refers to the area or container where the wafers are stored, which can be in other forms.

[0010] Preferably, the primary defect detection is automatically performed by a computer program, the process comprising: S1.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S1.2, obtaining images of the wafer taken at different positions; S1.3, analyzing the photographed wafer images, and recording defect information that meets the defect characteristics, the defect information including defect location, defect type, and the total number of all defects on the wafer, etc.; S1.4, determine whether high-magnification re-inspection is required. If so, end the first-level defect inspection. If not, proceed to the next step; S1.5, if the recorded defect information exceeds any of the thresholds set in the judgment condition, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set in the judgment condition, the inspected wafer is judged as qualified.

[0011] During the first-level defect inspection, the need for high-magnification re-inspection is determined. If high-magnification re-inspection is required, the first-level defect inspection only records the defect information and does not judge whether the wafer is qualified. If high-magnification re-inspection is not required, the qualification of the wafer is directly determined during the first-level defect inspection process.

[0012] Preferably, the high-magnification re-inspection is automatically performed by a computer program, and the process includes: S2.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S2.2, the wafer and the imaging device move relative to each other to obtain photos of the wafer taken at different positions; S2.3, analyzing the photo of the wafer and recording defect information that meets the defect characteristics, wherein the defect information includes defect location, defect type and total number of defects; S2.4, if the recorded defect information exceeds any of the thresholds set by the judgment conditions, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set by the judgment conditions, repeat steps S2.2 to S2.4 until the entire wafer is analyzed.

[0013] The above detection method can be automatically executed through a computer program to meet the needs of enterprises for automated wafer defect detection, and can also be adapted to automatic wafer production and defect detection production lines.

[0014] The above-mentioned defect characteristics include three-dimensional defects, line defects, point defects and surface defects, etc. Different judgment thresholds are set for these defect characteristics, such as the total area of ​​defects, the maximum length of defects, the number of defects, etc. Once one item exceeds the set value, it is considered unqualified.

[0015] Obviously, multiple items in the judgment threshold can be set as the basis for unqualified judgment.

[0016] At the same time, it is also obvious to set weights for the thresholds and calculate the wafer quality value through weight calculation.

[0017] Preferably, the wafer is placed in a designated location after inspection is completed. The modes of placing the wafer in the designated location include in-situ mode and classification mode. In the in-situ mode, the wafer that has completed inspection will be placed back to its original position; in the classification mode, at least one wafer storage area is required to be provided, and the wafer storage area is divided into a qualified area and a defective area. If the wafer is judged to be unqualified, the wafer is placed in the defective area, otherwise the wafer is placed in the qualified area.

[0018] On the basis of the above scheme, it is also necessary to model the wafer surface during wafer inspection, and partition the modeling to obtain N two-dimensional areas, where N is a positive integer, and the division of the two-dimensional area must meet the following requirements: the divided two-dimensional area can be clearly imaged at the same magnification, and each two-dimensional area is labeled and the test results are recorded after the inspection is completed. The two-dimensional area is used to mark the defective area of ​​the wafer, and the information recorded during marking includes the location of the two-dimensional area and the number of defects in the area. The two-dimensional area is divided to mark and record defect detection, and the recording method includes storing it in a computer-readable and writable data storage device.

[0019] All two-dimensional areas are clearly imaged at the same magnification, and there is no need to rescale and refocus during high-magnification re-inspection, which reduces the waiting time for defect detection and improves the overall efficiency of wafer defect detection.

[0020] One way to divide the two-dimensional area is: For a 12-inch wafer, that is, a wafer with a diameter of 300 mm, 18 layers of annular areas are divided from the center of the wafer. Each layer of the annular area has several 15 mm × 11 mm rectangles. The number of rectangles in the annular area from the inner layer to the outer layer is: 1, 4, 8, 13, 17, 20, 25, 27, 37, 37, 40, 40, 50, 50, 59, 59, 77 and 77.

[0021] Furthermore, the position of the two-dimensional area is uniquely determined through center positioning and angle positioning. The order of wafer positioning is to first locate the center of the wafer. After the center position of the wafer is determined, the center position of the wafer is coincided with the rotation center of the wafer. Subsequently, angle positioning is performed through the mark reserved on the wafer. Preferably, the position of the reserved mark is set to the rotation angle 0° position. The position of the two-dimensional area can be uniquely determined through the combination of center positioning and angle positioning.

[0022] Furthermore, the method of angularly positioning the two-dimensional area is to establish a coordinate system with the center of the wafer as the origin, and the coordinate system includes a polar coordinate system and a rectangular coordinate system.

[0023] During inspection, the positioned wafer and the imaging device also need to be moved relative to each other by a certain distance to ensure that the predetermined inspection area is within the imaging range.

[0024] Preferably, during the above-mentioned defect detection, the defects are divided into determined defect locations and suspected defect locations. The determined defect location is the information such as the defect and defect type that can be clearly distinguished through the first-level defect detection. There is no need to perform high-magnification re-inspection for such determined defect location. Only high-magnification re-inspection is performed on the suspected defect area where it is not possible to clearly distinguish whether it is a defect and the defect type is unclear, which can improve the detection accuracy. Performing high-magnification re-inspection on the suspected defect location alone can effectively improve the efficiency of defect detection while ensuring high accuracy.

[0025] Based on the above scheme, in step S5, the heights of the first detection surface and the second detection surface relative to the wafer surface are determined by a standard part. This detection method can detect three-dimensional defects that are not easy to find during plane detection. Since the specifications of wafers produced by different wafer factories are different, it is necessary to set the heights of the first detection surface and the second detection surface relative to the wafer surface through detection standard parts.

[0026] A second aspect of the present invention discloses a wafer positioning and defect detection device.

[0027] A third aspect of the present invention discloses a computer-readable storage medium storing a computer program, which implements the above-mentioned wafer positioning and defect detection method when the computer program is executed.

[0028] Compared with the prior art, the advantages of the present invention are: 1. The combined detection method of primary defect detection and high-magnification re-inspection ensures the accuracy of defect detection while improving the efficiency of defect detection; 2. During high-magnification re-inspection, an imaging device is used to image the defect position on the first inspection surface, the wafer surface, and the second inspection surface respectively. The defect information is updated by combining the three-dimensional imaging analysis. In addition to detecting planar defects, this detection method can further analyze the three-dimensional defects on the wafer, thereby improving the accuracy of defect detection; 3. Whether to conduct high-magnification re-inspection can be set according to the inspection requirements. If high-magnification re-inspection is not performed, the speed of defect detection can be accelerated; 4. The present invention can automatically judge and mark defects through computer programs. This automated detection method meets the needs of enterprises for automated detection of wafer defects. At the same time, it can adapt to the automatic wafer production and defect detection production line, reduce the cost and error of manual intervention, and improve the consistency and stability of production; 5. During defect detection, the position of the wafer and the angle of the wafer can be automatically restored through eccentricity correction and angle positioning, ensuring the accuracy and consistency of defect detection and eliminating the position offset problem caused by manual wafer transfer. The combination of center positioning and angle positioning is used to further establish a coordinate system, which can uniquely determine the position of the two-dimensional area. The positioning method is simple and reliable. 6. It can automatically detect multiple wafers without manual wafer replacement in the middle, preventing position errors or wafer damage caused by manual replacement and reducing manpower consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the overall flow chart of the present invention.

[0030] Figure 2 This is the first-level defect detection flow chart.

[0031] Figure 3 This is the high-magnification re-inspection flow chart.

[0032] Figure 4 Schematic diagram of the first two-dimensional area division.

[0033] Figure 5 Schematic diagram of the second two-dimensional area division.

[0034] Figure 6 Schematic diagram of the third two-dimensional area division. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with specific implementations and accompanying drawings.

[0036] like Figure 1As shown, the present invention provides a wafer positioning and defect detection method, which includes the following steps: S1, scan and record the positions of all wafers to be inspected; S2, taking out the wafer to be inspected according to the recorded wafer position; S3, wafer eccentricity correction and angle positioning; S4, performing a primary defect inspection on the wafer and recording defect information, wherein the defect information includes a defect location, a defect type, and a total number of defects on the wafer; S5, if the wafer still needs to be re-inspected at a high magnification, the defect position is found again by angle positioning, and the defect position is re-inspected at a high magnification. During the high magnification re-inspection, an imaging device is used to image the defect position on the first detection surface, the wafer surface, and the second detection surface respectively, and the defect information is updated by combining the three plane imaging analysis. If the wafer does not need a high magnification re-inspection, the next step is directly performed; S6, complete wafer defect detection and record the detection results.

[0037] In other embodiments, during high-magnification re-inspection, the wafer is re-corrected for eccentricity and re-positioned for angle to prevent eccentricity errors from occurring during wafer rotation inspection, which in turn leads to inaccurate positioning of defect positions and affects the accuracy of wafer inspection.

[0038] In other embodiments, primary defect detection and high-magnification detection are performed on two devices respectively. In this case, in order to accurately locate the defect position, it is also necessary to perform eccentricity correction and angle positioning on the wafer.

[0039] The heights of the first detection surface and the second detection surface relative to the wafer surface are set by a process of detecting a standard part.

[0040] In other embodiments, the positions of the first detection surface and the second detection surface can be set by manual input.

[0041] The defect location is used for subsequent high-magnification re-inspection. In other embodiments, for wafers that only require primary defect detection, the defect information only records the defect type and the total number of defects.

[0042] Angle positioning uses the reserved mark on the wafer as the starting point of detection. The reserved mark types include: flat edge or notch, etc.

[0043] In other embodiments, the angle positioning initial point is set by manual addition.

[0044] In other embodiments, more than one mark is reserved on the wafer. In this case, the angle between the multiple marks is used to calculate the initial point of the angle positioning. By calculating the angle between the multiple marks, the initial point of the angle positioning can be set as needed.

[0045] During wafer inspection, the modes for scanning and recording wafer positions include traversal mode and selection mode: In the traversal mode, all wafers in the wafer storage area are inspected for defects in sequence; In the selection mode, the number and location of wafers to be inspected in the wafer storage area are manually selected according to the needs of defect detection.

[0046] The wafer storage area can be implemented in many ways, including: a conveyor, a CASSETTE (open wafer carrier), a FOUP (front opening wafer transfer box) and a FOSB (front opening wafer shipping box) and other devices for storing wafers, or a virtual or real partition on a conveyor.

[0047] like Figure 2 As shown, the process of primary defect detection is as follows: S1.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S1.2, obtaining photos of the wafer taken at different positions; S1.3, analyzing the photo of the wafer and recording defect information that meets the defect characteristics, wherein the defect information includes defect location, defect type and total number of defects; S1.4, determine whether high-magnification re-inspection is required. If so, end the first-level defect inspection. If not, proceed to the next step; S1.5, if the recorded defect information exceeds any of the thresholds set in the judgment condition, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set in the judgment condition, the inspected wafer is judged as qualified.

[0048] like Figure 3 The detailed process of high-magnification re-inspection is as follows: S2.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S2.2, the wafer and the imaging device move relative to each other to obtain photos of the wafer taken at different positions; S2.3, analyzing the photo of the wafer and recording defect information that meets the defect characteristics, wherein the defect information includes defect location, defect type and total number of defects; S2.4, if the recorded defect information exceeds any of the thresholds set by the judgment conditions, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set by the judgment conditions, repeat steps S2.2 to S2.4 until the entire wafer is analyzed.

[0049] Among them, the defect information involved in the judgment includes defect location, defect length, maximum defect length, defect percentage, total defect area, defect type and defect quantity, that is, different or the same thresholds are set for any number of the above defect information parameters. If one defect information parameter exceeds the set threshold, it is judged as unqualified.

[0050] In other embodiments, weights of different thresholds are set, and weighted calculation methods such as weighted summation are performed on different thresholds to calculate qualified parameters of the wafer.

[0051] In other embodiments, the wafer inspection area may be manually selected, and defects may be actively introduced into the unselected area to serve as a marker point or marker position for wafer area positioning.

[0052] In other embodiments, an area with a pattern on the wafer is automatically selected as the detection area. The wafer with a pattern is usually a wafer on which a circuit structure has been engraved. Detecting only the area with the pattern can also ensure high efficiency of wafer detection.

[0053] In other embodiments, defect detection on the wafer is performed using a machine learning algorithm.

[0054] In other embodiments, both the primary defect detection and high-magnification re-inspection will determine whether the wafer is qualified, record the defect information on the wafer, and further determine whether the wafer is qualified through manual judgment or weighted calculation.

[0055] After wafer inspection is completed, the wafer is stored in a designated location. The wafer storage modes include in-situ mode and classification mode: In the in-situ mode, the wafer after inspection is placed back to the original position, specifically the wafer position recorded in step S1; In the classification mode, a wafer storage area is set, and the wafer storage area is further divided into a qualified area and a defective area. If a wafer is judged to be unqualified, the corresponding wafer is placed in the defective area, otherwise the wafer is placed in the qualified area.

[0056] In other embodiments, the classification mode sets two or more wafer storage areas, and any area therein is divided into a qualified area, and other areas are divided into defective areas.

[0057] The defect information recorded during wafer inspection is also divided into confirmed defect information and suspected defect information. During high-magnification re-inspection, only the suspected defect information is tested, and the location of the confirmed defect is no longer tested. This is used to classify defects and further improve the efficiency of defect detection.

[0058] In other embodiments, the defect information is manually divided into confirmed defect information and suspected defect information for subsequent re-inspection.

[0059] During wafer defect detection, the wafer surface is modeled and partitioned to obtain N two-dimensional areas, where N is a positive integer, to ensure that all divided two-dimensional areas can be clearly imaged at the same magnification to facilitate defect detection. After the detection is completed, the detection results of each two-dimensional area are marked and recorded. The recording method can be stored in a computer-readable and writable data storage device, which includes a memory, a USB flash drive and other devices.

[0060] like Figure 4 As shown, the two-dimensional area is divided as follows: The division of the wafer is based on the sampling range of the imaging device and the different sizes of the wafer. For a 12-inch wafer, 18 layers of annular areas are divided from the center of the wafer. Each layer of the annular area has several 15mm×11mm rectangles. The number of rectangles in the annular area from the inner layer to the outer layer, that is, from the R layer to the A layer, are 1, 4, 8, 13, 17, 20, 25, 27, 37, 37, 40, 40, 50, 50, 59, 59, 77 and 77 respectively.

[0061] The rectangles in the R layer, Q layer, and P layer are respectively about Figure 4 The center line of the cross is symmetrical left to right and up to down.

[0062] This division method can ensure that the sampling range of the imaging device covers the entire wafer without omission.

[0063] One of the two-dimensional region partitioning methods is Figure 5 As shown, starting from the center of the wafer, M concentric circles are divided, where M is a positive integer. The non-minimum concentric circle is further divided into fan rings, and the areas of all fan rings are the same. In this way, there is no need to re-enlarge and focus during high-magnification re-inspection, which simplifies the inspection process.

[0064] Another implementation example is Figure 6 As shown, starting from the center of the wafer, P concentric circles are divided, where P is a positive integer. The non-minimum concentric circles are further divided into fan rings through a set of radii, and the straight sides of all fan rings are in the direction of this set of radii.

[0065] In other embodiments, the inspection area may be divided into other shapes according to inspection needs or subject to inspection methods, such as further dividing the minimum concentric circle into sectors or dividing the wafer into other shapes such as rectangles and triangles based on the angle positioning initial point.

[0066] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0067] Although the above describes the specific implementation methods of the present invention, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A wafer positioning and defect detection method, characterized in that: There are the following processes: S1, scan and record the positions of all wafers to be inspected; S2, taking out the wafer to be inspected according to the position of the wafer; S3, positioning the wafer, including eccentricity correction and angle positioning; S4, performing a primary defect inspection on the wafer and recording defect information, wherein the defect information includes defect position, defect length, maximum defect length, defect percentage, total defect area, defect type and defect quantity; S5, if the wafer needs high-magnification re-inspection, find the recorded defect position through angle positioning, and re-inspect the defect position at a high magnification. During the high-magnification re-inspection, an imaging device is used to image the defect position on the first detection surface, the wafer surface, and the second detection surface respectively. The first detection surface is higher than the wafer surface, and the second detection surface is lower than the wafer surface. The three plane imaging analyses are combined to update the defect information; if the wafer does not need high-magnification re-inspection, proceed directly to the next step; S6, complete wafer defect detection and record the detection results.

2. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: Modes for scanning and recording wafer positions include a traversal mode and a selection mode; In the traversal mode, all wafers in the wafer storage area are sequentially inspected for defects; In the selection mode, the number and position of wafers to be inspected in the wafer storage area are manually selected.

3. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: The first-level defect detection is automatically performed by a computer program, and the process is as follows: S1.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S1.2, obtaining photos of the wafer taken at different positions; S1.3, analyzing the photos of the wafer and recording defect information that meets the defect characteristics, the defect information including defect location, defect length, maximum defect length, defect percentage, total defect area, defect type and defect quantity; S1.4, determine whether high-magnification re-inspection is required. If so, end the first-level defect inspection. If not, proceed to the next step; S1.5, if the recorded defect information exceeds any of the thresholds set in the judgment condition, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set in the judgment condition, the inspected wafer is judged as qualified.

4. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: The high-magnification re-inspection is automatically performed by a computer program, and the process is as follows: S2.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S2.2, the wafer and the imaging device move relative to each other to obtain photos of the wafer taken at different positions; S2.3, analyzing the photo of the wafer, and recording defect information that meets the judgment basis, wherein the defect information includes defect location, defect type, and total number of defects; S2.4, if the recorded defect information exceeds any of the thresholds set by the judgment condition, the wafer is judged to be unqualified; if the recorded defect information does not exceed any of the thresholds set by the judgment condition, steps S2.2 to S2.4 are repeated until the entire wafer is analyzed.

5. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: During wafer defect detection, the wafer surface is modeled and partitioned to obtain N two-dimensional areas, ensuring that all the two-dimensional areas are clearly imaged at the same magnification, where N is a positive integer. After the detection is completed, each two-dimensional area is labeled and the detection result is recorded. A coordinate system is established through angular positioning to uniquely determine the position of the two-dimensional area.

6. A wafer positioning and defect detection method as claimed in claim 5, characterized in that: The two-dimensional area is divided as follows: for a 12-inch wafer, 18 layers of annular areas are divided starting from the center of the wafer, each layer of the annular area is composed of several 15mm×11mm rectangles, and the number of rectangles in the annular area from the inner layer to the outer layer are: 1, 4, 8, 13, 17, 20, 25, 27, 37, 37, 40, 40, 50, 50, 59, 59, 77 and 77 respectively.

7. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: After wafer inspection is completed, it is stored in the designated location.

8. A wafer positioning and defect detection method as claimed in claim 7, characterized in that: The modes of storing wafers at designated locations after inspection include in-situ mode and classification mode; In the in-situ mode, the wafer after inspection is placed back to its original position; In the classification mode, at least one wafer storage area is set, and the wafer storage area includes a qualified area and a defective area. If a wafer is judged to be unqualified, the unqualified wafer is placed in the defective area, otherwise the finished wafer is placed in the qualified area.

9. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: The heights of the first detection surface and the second detection surface relative to the wafer surface are identified by inputting a standard part.

10. A wafer positioning and defect detection method as claimed in claim 1, characterized in that: The recorded defect information includes confirmed defect information and suspected defect information. When conducting high-magnification re-inspection, only the defect locations recorded in the suspected defect information are inspected.

11. A wafer positioning and defect detection device, characterized in that: include: A device for scanning and recording the positions of all wafers to be inspected; A device for traversing and taking out wafers to be inspected according to the positions of the wafers; A device for positioning the wafer, including eccentricity correction and angle positioning; A device for performing primary defect detection on the wafer and recording defect information, wherein the defect information includes defect location, defect type and defect quantity; If the wafer needs high-magnification re-inspection, the recorded defect position is found through angle positioning, and the defect position is re-inspected at a high magnification. During the high-magnification re-inspection, an imaging device is used to image the defect position on the first detection surface, the wafer surface, and the second detection surface respectively. The first detection surface is higher than the wafer surface, and the second detection surface is lower than the wafer surface. The three plane imaging analyses are combined to update the defect information; if the wafer does not need high-magnification re-inspection, the device for directly proceeding to the next step; A device used to complete wafer defect detection and record the detection results.

12. The wafer positioning and defect detection device according to claim 11, characterized in that: Modes for scanning and recording wafer positions include a traversal mode and a selection mode; In the traversal mode, all wafers in the wafer storage area are sequentially inspected for defects; In the selection mode, the number and position of wafers to be inspected in the wafer storage area are manually selected.

13. The wafer positioning and defect detection device according to claim 11, characterized in that: The first-level defect detection is automatically performed by a computer program, and the process is as follows: S3.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S3.2, obtaining photos of the wafer taken at different positions; S3.3, analyzing the photograph of the wafer and recording defect information that meets the defect characteristics, the defect information including defect location, defect length, maximum defect length, defect percentage, total defect area, defect type and defect quantity; S3.4, determine whether high-rate re-inspection is required. If so, end the first-level defect inspection. If not, proceed to the next step. S3.5, if the recorded defect information exceeds any of the thresholds set in the judgment condition, the inspected wafer is judged as unqualified; if the recorded defect information does not exceed any of the thresholds set in the judgment condition, the inspected wafer is judged as qualified.

14. The wafer positioning and defect detection device according to claim 11, characterized in that: The high-magnification re-inspection is automatically performed by a computer program, and the process is as follows: S4.1, setting a defect judgment condition according to the defect characteristics, wherein the judgment condition is to set a corresponding threshold for any item in the defect information; S4.2, the wafer and the imaging device move relative to each other to obtain photographs of the wafer taken at different positions; S4.3, analyzing the photo of the wafer, and recording defect information that meets the judgment basis, the defect information including defect location, defect type and total number of defects; S4.4, if the recorded defect information exceeds any of the thresholds set by the judgment condition, the wafer is judged to be unqualified; if the recorded defect information does not exceed any of the thresholds set by the judgment condition, steps S4.2 to S4.4 are repeated until the entire wafer is analyzed.

15. The wafer positioning and defect detection device according to claim 11, characterized in that: During wafer defect detection, the wafer surface is modeled and partitioned to obtain N two-dimensional areas, ensuring that all the two-dimensional areas are clearly imaged at the same magnification, where N is a positive integer. After the detection is completed, each two-dimensional area is labeled and the detection result is recorded. A coordinate system is established through angular positioning to uniquely determine the position of the two-dimensional area.

16. The wafer positioning and defect detection device according to claim 15, characterized in that: The two-dimensional area is divided as follows: for a 12-inch wafer, 18 layers of annular areas are divided starting from the center of the wafer, each layer of the annular area is composed of several 15mm×11mm rectangles, and the number of rectangles in the annular area from the inner layer to the outer layer are: 1, 4, 8, 13, 17, 20, 25, 27, 37, 37, 40, 40, 50, 50, 59, 59, 77 and 77 respectively.

17. The wafer positioning and defect detection device according to claim 11, characterized in that: After wafer inspection is completed, it is stored in the designated location.

18. The wafer positioning and defect detection device according to claim 17, characterized in that: The modes of storing wafers at designated locations after inspection include in-situ mode and classification mode; In the in-situ mode, the wafer after inspection is placed back to its original position; In the classification mode, at least one wafer storage area is set, and the wafer storage area includes a qualified area and a defective area. If a wafer is judged to be unqualified, the unqualified wafer is placed in the defective area, otherwise the finished wafer is placed in the qualified area.

19. The wafer positioning and defect detection device according to claim 11, characterized in that: The heights of the first detection surface and the second detection surface relative to the wafer surface are identified by inputting a standard part.

20. The wafer positioning and defect detection device according to claim 11, characterized in that: The recorded defect information includes confirmed defect information and suspected defect information. When conducting high-magnification re-inspection, only the defect locations recorded in the suspected defect information are inspected.

21. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed, the wafer positioning and defect detection method described in any one of claims 1 to 10 is implemented.

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