Silicon wafer edge grinding method and device

Abstract

The invention provides a silicon wafer edge grinding method and device, and relates to the technical field of semiconductors, the silicon wafer edge grinding method comprises the following steps: detecting a silicon wafer subjected to linear cutting to obtain position information and size information of an edge breakage defect of an edge area of the silicon wafer; determining a grinding center for grinding the edge of the silicon wafer according to the position information and the size information of the edge breakage defect; and according to the grinding center and a target radius, edge grinding is conducted on the silicon wafer, and the target radius is the radius of the silicon wafer obtained after edge grinding is conducted on the silicon wafer. In the edge grinding process, the edge defect of the silicon wafer can be more effectively ground, the situation that the silicon wafer is scrapped is reduced, and the yield of the silicon wafer is improved.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a method and device for grinding an edge of a silicon wafer. Background Art

[0002] The main process of processing silicon wafers includes: wire cutting of silicon wafers, edge grinding of silicon wafers after wire cutting, double-sided grinding of silicon wafers after edge grinding, etching of double-sided ground silicon wafers, double-sided polishing of etched silicon wafers, and cleaning of double-sided polished silicon wafers to obtain processed silicon wafers.

[0003] In the above-mentioned process of edge grinding of the silicon wafer after wire cutting, the radius of the edge grinding of the silicon wafer is generally set, and then the silicon wafer after wire cutting is obtained, and the silicon wafer is positioned using the notch of the silicon wafer, and the original center of the silicon wafer is used as the radius. The edge of the silicon wafer is ground according to the set radius after the edge grinding of the silicon wafer, and the silicon wafer is cleaned and dried after grinding.

[0004] However, after the silicon wafer is wire-cut, there are often some edge collapse defects near the edge of the silicon wafer, and the edge collapse defects cannot be completely removed according to the above-mentioned edge grinding process, which causes the silicon wafer to be broken during the subsequent process.

[0005] Therefore, it is necessary to grind away the edge chipping defects during the edge grinding of the silicon wafer to ensure the quality of subsequent silicon wafers. However, according to the existing edge grinding method, the edge chipping defects are often not effectively ground away, resulting in the silicon wafer being scrapped and the silicon wafer yield being low. Summary of the invention

[0006] The embodiment of the present invention provides a silicon wafer edge grinding method and device, which are used to solve the problem that the chipped edge defects cannot be effectively ground away when the silicon wafer edge is ground in the prior art.

[0007] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0008] An embodiment of the present invention provides a silicon wafer edge grinding method, comprising:

[0009] Detecting the silicon wafer after wire cutting to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer;

[0010] Determining a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect;

[0011] The edge of the silicon wafer is ground according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after the edge of the silicon wafer is ground.

[0012] In some embodiments, the silicon wafer after wire cutting is inspected to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer, including:

[0013] Scanning the surface of the silicon wafer after the wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer;

[0014] According to the reflection intensity, the position information and size information of the edge collapse defect on the surface of the silicon wafer are obtained.

[0015] In some embodiments, scanning the surface of the silicon wafer after wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer includes:

[0016] Controlling the silicon wafer to rotate;

[0017] During the rotation of the silicon wafer, the laser beam is controlled to move radially from the center of the surface of the wire-cut silicon wafer to the edge of the surface of the wire-cut silicon wafer to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer.

[0018] In some embodiments, determining a grinding center for edge grinding of the silicon wafer according to the location information and size information of the edge collapse defect includes:

[0019] Determine, according to the position information and the size information, a first position coordinate on the edge collapse defect that is closest to the center of the surface of the silicon wafer after wire cutting;

[0020] A grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates.

[0021] In some embodiments, determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes:

[0022] When the number of the edge collapse defects is two, obtaining a first position coordinate corresponding to a first edge collapse defect of the two edge collapse defects and a first position coordinate corresponding to a second edge collapse defect of the two edge collapse defects;

[0023] Determine a first preselected center coordinate according to a first position coordinate corresponding to the first edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0024] Determine a second preselected center coordinate according to a first position coordinate corresponding to the second edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0025] A grinding center for edge grinding of the silicon wafer is determined according to the first preselected center coordinates and the second preselected center coordinates.

[0026] In some embodiments, determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes:

[0027] When the number of the edge collapse defects is greater than or equal to 3, determining a third edge collapse defect, a fourth edge collapse defect, and a central edge collapse defect among the edge collapse defects according to the position information and the size information;

[0028] Obtaining a first position coordinate corresponding to the third edge chipping defect, a first position coordinate corresponding to the fourth edge chipping defect, and a first position coordinate corresponding to the central edge chipping defect;

[0029] The grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates corresponding to the third edge chipping defect, the first position coordinates corresponding to the fourth edge chipping defect, and the first position coordinates corresponding to the central edge chipping defect.

[0030] In some embodiments, determining the third edge chipping defect, the fourth edge chipping defect, and the center edge chipping defect among the edge chipping defects according to the position information and the size information includes:

[0031] Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the clockwise direction along the circumference of the silicon wafer is the third edge collapse defect;

[0032] Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the counterclockwise direction along the circumference of the silicon wafer is the fourth edge collapse defect;

[0033] Among the edge chipping defects, the edge chipping defect farthest from the notch of the silicon wafer along the circumferential direction of the silicon wafer is determined as the central edge chipping defect.

[0034] In some embodiments, determining the grinding center for edge grinding of the silicon wafer according to the first position coordinates corresponding to the third edge chipping defect, the first position coordinates corresponding to the fourth edge chipping defect, and the first position coordinates corresponding to the center edge chipping defect includes:

[0035] Generating a first line segment between the first position coordinate corresponding to the third edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0036] Generating a second line segment between the first position coordinate corresponding to the fourth edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0037] The intersection of the perpendicular bisector of the first line segment and the perpendicular bisector of the second line segment is used as a grinding center for edge grinding of the silicon wafer.

[0038] In some embodiments, edge grinding of the silicon wafer is performed according to the grinding center and the target radius, including:

[0039] Determine, according to the position information and the size information, a second position coordinate on the chipping defect that is closest to the grinding center;

[0040] When the distance between the second position coordinate and the grinding center is greater than the target radius, edge grinding is performed on the silicon wafer according to the grinding center and the target radius.

[0041] The embodiment of the present invention further provides a silicon wafer edge grinding device, comprising:

[0042] The first processing module is used to detect the silicon wafer after wire cutting to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer;

[0043] A first determination module is used to determine a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect;

[0044] The second processing module is used to perform edge grinding on the silicon wafer according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after the edge grinding of the silicon wafer.

[0045] The embodiments of the present invention have the following beneficial effects:

[0046] The silicon wafer edge grinding method provided in the embodiment of the present invention detects the silicon wafer after wire cutting, obtains the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer, and determines the grinding center when edge grinding the silicon wafer considering the position information and size information of the edge collapse defect. The grinding center is not the surface center of the silicon wafer after cutting. The silicon wafer is edge ground according to the grinding center and a pre-set target radius after grinding the silicon wafer. In the above manner, the edge defects of the silicon wafer can be ground off more effectively during the edge grinding process, the situation of silicon wafer being scrapped can be reduced, and the yield rate of the silicon wafer can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 One of the schematic diagrams showing the edge grinding of a silicon wafer provided by an embodiment of the present invention;

[0048] Figure 2 A flow chart showing a method for grinding a silicon wafer edge according to an embodiment of the present invention;

[0049] Figure 3 A second schematic diagram showing the grinding of the edge of a silicon wafer provided by an embodiment of the present invention;

[0050] Figure 4 One of the schematic diagrams showing the grinding center provided by the embodiment of the present invention;

[0051] Figure 5 A second schematic diagram showing a grinding center provided by an embodiment of the present invention;

[0052] Figure 6 A third schematic diagram showing a grinding center provided by an embodiment of the present invention;

[0053] Figure 7 A schematic diagram showing the structure of a silicon wafer edge grinding device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0054] In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0055] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0056] Before describing the specific embodiments of the present invention, the following description is first given:

[0057] See also Figure 1 , the diameter of the silicon wafer after wire cutting is 301mm, and the diameter of the silicon wafer after edge grinding is 300.5mm. On one diameter, the edge removal is 500um, and on the radius, the edge removal is 250um. Figure 1 As shown in FIG. 1 , there are three edge collapse defects on the edge of the silicon wafer. Among the three edge collapse defects, the maximum radial size of the edge collapse defect is 300 μm. The surface center of the silicon wafer after wire cutting is used as the processing center to grind the edge of the silicon wafer. The silicon wafer after edge grinding is as shown in FIG. Figure 1 As shown, it can be seen that the edge collapse defect cannot be effectively ground away, resulting in the silicon wafer being scrapped.

[0058] In order to solve the problem in the prior art that the chipped edge defects cannot be effectively ground away when the edge of a silicon wafer is ground, an embodiment of the present invention provides a method and device for grinding the edge of a silicon wafer.

[0059] like Figure 2 As shown, an embodiment of the present invention provides a silicon wafer edge grinding method, comprising:

[0060] Step 201: inspecting the silicon wafer after wire cutting to obtain position information and size information of edge collapse defects in the edge area of ​​the silicon wafer.

[0061] In this step, a coordinate system can be first established on the surface of the silicon wafer after cutting. The coordinate center of the coordinate system is the surface center of the silicon wafer after wire cutting. The surface center of the silicon wafer is connected with the notch of the silicon wafer. A vertical coordinate axis is established on the straight line where the connecting line is located, and a horizontal coordinate axis is established on the straight line perpendicular to the straight line where the connecting line is located.

[0062] The silicon wafer after wire cutting is inspected to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer. The edge area of ​​the silicon wafer can be set as an area whose distance from the edge of the silicon wafer in the radial direction is less than a preset distance.

[0063] The position information includes the position coordinates of the edge chipping defect, and the position coordinates of the edge chipping defect may be the center position coordinates of the edge chipping defect.

[0064] The size information includes the position coordinates of the edge of the chipping defect, that is, the position coordinates of the edge of the chipping defect can reflect the shape and size of the chipping defect.

[0065] According to the position coordinates of the edge of the chipped edge defect, the center position coordinates of the chipped edge defect can be calculated. Specifically, according to the position coordinates of the edge of the chipped edge defect, the first position coordinates of the two edge points on the chipped edge defect that are farthest apart in the radial direction are obtained, and the second position coordinates of the two edge points on the chipped edge defect that are farthest apart in the circumferential direction are obtained. The two first position coordinates are connected by a line, and the two second position coordinates are connected by a line. The coordinates of the intersection of the two lines are the center position coordinates of the chipped edge defect.

[0066] It can be understood that the position information is used to indicate the position of the edge collapse defect on the silicon wafer, and the size information is used to indicate the shape and size of the edge collapse defect.

[0067] It should be noted that the number of the edge collapse defect is at least one.

[0068] If edge collapse defects occur in the non-edge region of the silicon wafer, that is, in the central region of the silicon wafer, there is no need to perform subsequent edge grinding steps, and the silicon wafer is determined to be scrapped.

[0069] Step 202: Determine a grinding center for edge grinding of the silicon wafer according to the location information and size information of the edge collapse defect.

[0070] In this step, the position information and size information of each edge collapse defect are taken into consideration, and the grinding center of the silicon wafer is re-determined based on the position information and size information, wherein the grinding center is different from the surface center of the silicon wafer, and the grinding center of the silicon wafer can also be expressed in the form of coordinates in the above-mentioned coordinate system.

[0071] Step 203: performing edge grinding on the silicon wafer according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after edge grinding of the silicon wafer.

[0072] It should be noted that the radius of the silicon wafer after edge grinding is preset. For example, if the diameter of the silicon wafer to be obtained after edge grinding is 300.5 mm, the target radius is 150.25 mm.

[0073] After the grinding center is obtained by the above steps, the grinding center is used as a processing center for edge grinding. After the silicon wafer is ground to a target radius, the grinding is stopped to complete the edge grinding process.

[0074] For example, the above Figure 1 As an example, a silicon wafer after wire cutting shown in FIG. 1 and having three edge collapse defects on the silicon wafer is used to determine the grinding center of the silicon wafer by using the above steps. The edge of the silicon wafer is ground according to the grinding center. The ground silicon wafer is as shown in FIG. Figure 3 As shown, it can be seen that by implementing the silicon wafer edge grinding method provided by the present invention, the grinding center of the silicon wafer is re-determined, and the edge collapse defects on the silicon wafer can be more effectively ground away, reducing the situation of silicon wafers being scrapped and improving the yield rate of silicon wafers.

[0075] In some embodiments, the silicon wafer after wire cutting is inspected to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer, including:

[0076] Scanning the surface of the silicon wafer after the wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer;

[0077] Specifically, a laser beam is used to scan the surface of a silicon wafer to ensure that the laser beam can be projected to all positions on the surface of the silicon wafer. The laser beam is reflected from the surface of the silicon wafer. When the laser beam encounters particles or other defects on the surface of the silicon wafer, the particles or defects will scatter a portion of the laser light. The scattered laser light enters the silicon wafer, and the particle or defect structure will become brighter. The portion of the silicon wafer without particles or defects is relatively dark. A photomultiplier tube (PMT) or a charge-coupled device (CCD) is used to electronically record the light intensity at different positions on the surface of the silicon wafer, and the reflection intensity on the surface of the silicon wafer is generated based on the light intensity.

[0078] According to the reflection intensity, the position information and size information of the edge collapse defect on the surface of the silicon wafer are obtained. That is, the reflection intensity is used to indicate the particles or defect patterns on the surface of the silicon wafer.

[0079] Further, a laser beam is used to scan the surface of the silicon wafer after the wire cutting to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer, including:

[0080] The silicon wafer can be controlled to rotate by placing the silicon wafer on a silicon wafer carrier, and the silicon wafer can be driven to rotate by rotating the silicon wafer carrier.

[0081] During the rotation of the silicon wafer, the laser beam is controlled to move radially from the center of the surface of the wire-cut silicon wafer to the edge of the surface of the wire-cut silicon wafer to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer.

[0082] That is, by controlling the silicon wafer to perform high-precision and repeatable rotational motion, and controlling the laser beam to perform high-precision linear motion, the reflection intensity at different positions on the surface of the silicon wafer is scanned and obtained, wherein different positions on the surface of the silicon wafer can be indicated in the form of coordinates.

[0083] It should be noted that, when controlling the laser beam to move radially from the center of the surface of the silicon wafer after wire cutting to the edge of the surface of the silicon wafer after wire cutting, the laser beam can be controlled to move a smaller distance after each rotation of the silicon wafer one or several circles, and then the silicon wafer can be controlled to rotate one or several circles to ensure that the laser beam fully scans the surface of the silicon wafer.

[0084] In some embodiments, determining a grinding center for edge grinding of the silicon wafer according to the location information and size information of the edge collapse defect includes:

[0085] Based on the position information and the size information, determine the first position coordinate on the chipped edge defect that is closest to the surface center of the silicon wafer after wire cutting. Specifically, based on the position information and the size information, determine the distance between each position point in the chipped edge defect and the surface center of the silicon wafer after wire cutting (i.e., the center of the coordinate system) in the above-mentioned coordinate system, and use the coordinate of the position point that is closest to the first position coordinate.

[0086] In the case where there are multiple edge chipping defects, the first position coordinates corresponding to each edge chipping defect are acquired in sequence according to the above process.

[0087] A grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates.

[0088] In an optional implementation manner, when the number of the edge collapse defect is one, determining a grinding center for edge grinding the silicon wafer according to the first position coordinates includes:

[0089] like Figure 4 As shown, the surface center of the silicon wafer after wire cutting is set to P, the coordinates are set to P(0,0), and the first position coordinates of the edge collapse defect are set to (x1, y1). According to the surface radius R of the silicon wafer after wire cutting and the first position coordinates, the eccentricity calculation is performed according to the following formula to calculate the grinding center P(a1, b2):

[0090]

[0091] In an optional implementation manner, determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes:

[0092] When the number of the edge collapse defects is two, obtaining a first position coordinate corresponding to a first edge collapse defect of the two edge collapse defects and a first position coordinate corresponding to a second edge collapse defect of the two edge collapse defects;

[0093] Determine a first preselected center coordinate according to a first position coordinate corresponding to the first edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0094] Determine a second preselected center coordinate according to a first position coordinate corresponding to the second edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0095] A grinding center for edge grinding of the silicon wafer is determined according to the first preselected center coordinates and the second preselected center coordinates. Specifically, a midpoint coordinate of the first preselected center coordinates and the second preselected center coordinates is used as the grinding center.

[0096] Specifically, Figure 5As shown, the surface center of the silicon wafer after wire cutting is set to P, the coordinates are set to P(0,0), the first position coordinates corresponding to the first edge collapse defect are set to (x1, y1), and the first position coordinates corresponding to the second edge collapse defect are set to (x2, y2). According to the surface radius R of the silicon wafer after wire cutting and the first position coordinates corresponding to the first edge collapse defect, the eccentricity calculation is performed according to the following formula to obtain the first pre-selected center coordinates:

[0097]

[0098] Wherein, a1 represents the abscissa of the first preselected center, and b1 represents the ordinate of the first preselected center.

[0099] According to the surface radius R of the silicon wafer after wire cutting and the first position coordinates corresponding to the second edge collapse defect, the eccentricity is calculated according to the following formula to obtain the second pre-selected center coordinates:

[0100]

[0101] Wherein, a2 represents the abscissa of the second preselected center, and b2 represents the ordinate of the second preselected center.

[0102] Then, the grinding center P' for edge grinding of the silicon wafer is calculated according to the following formula:

[0103]

[0104] In an optional implementation manner, determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes:

[0105] When the number of edge collapse defects is greater than or equal to 3, the third edge collapse defect, the fourth edge collapse defect and the central edge collapse defect among the edge collapse defects are determined according to the position information and the size information, that is, when the number of edge collapse defects is greater than or equal to 3, three edge collapse defects are selected from multiple edge collapse defects, namely the third edge collapse defect, the fourth edge collapse defect and the central edge collapse defect; wherein the third edge collapse defect and the fourth edge collapse defect are two edge collapse defects at the maximum distribution angle relative to the notch of the silicon wafer;

[0106] Obtaining a first position coordinate corresponding to the third edge chipping defect, a first position coordinate corresponding to the fourth edge chipping defect, and a first position coordinate corresponding to the central edge chipping defect;

[0107] According to the first position coordinates corresponding to the third edge collapse defect, the first position coordinates corresponding to the fourth edge collapse defect, and the first position coordinates corresponding to the central edge collapse defect, the grinding center for edge grinding of the silicon wafer is determined. That is, the grinding center for edge grinding of the silicon wafer can be calculated by only using the first position coordinates corresponding to the three edge collapse defects selected above.

[0108] Wherein, determining the third edge collapse defect, the fourth edge collapse defect and the central edge collapse defect among the edge collapse defects according to the position information and the size information includes:

[0109] In determining the edge collapse defect, the edge collapse defect closest to the notch of the silicon wafer in the clockwise direction along the circumference of the silicon wafer is the third edge collapse defect, such as Figure 6 As shown, the first position coordinate corresponding to the third edge collapse defect is (x1, y1);

[0110] In determining the edge collapse defect, the edge collapse defect closest to the notch of the silicon wafer in the counterclockwise direction along the circumference of the silicon wafer is the fourth edge collapse defect, such as Figure 6 As shown, the first position coordinate corresponding to the third edge collapse defect is (x3, y3);

[0111] Among the edge collapse defects, the edge collapse defect farthest from the notch of the silicon wafer along the circumferential direction of the silicon wafer is determined as the central edge collapse defect, such as Figure 6 As shown, the first position coordinate corresponding to the central edge collapse defect is (x2, y2).

[0112] Wherein, determining the grinding center for edge grinding of the silicon wafer according to the first position coordinates corresponding to the third edge collapse defect, the first position coordinates corresponding to the fourth edge collapse defect, and the first position coordinates corresponding to the central edge collapse defect includes:

[0113] Continue as Figure 6 As shown, a first line segment is generated between the first position coordinate corresponding to the third edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0114] Generating a second line segment between the first position coordinate corresponding to the fourth edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0115] The intersection of the perpendicular bisector of the first line segment and the perpendicular bisector of the second line segment is used as a grinding center for edge grinding of the silicon wafer.

[0116] Specifically, Figure 6As shown, the center of the surface of the silicon wafer after wire cutting is set to P, and the coordinates are set to P(0,0). According to the following formula, the slope m1 of the perpendicular bisector of the first line segment and the slope m2 of the perpendicular bisector of the second line segment are calculated:

[0117]

[0118] After that, the grinding center is calculated as follows:

[0119]

[0120] Wherein, a1 represents the abscissa of the grinding center, and b1 represents the ordinate of the grinding center.

[0121] The present invention performs defect detection on silicon wafers after wire cutting to obtain position information and size information of edge collapse defects, and calculates a reasonable processing center (i.e., grinding center) based on the position information and size information, so as to more effectively remove edge defects and improve product yield.

[0122] like Figure 7 As shown, an embodiment of the present invention further provides a silicon wafer edge grinding device, comprising:

[0123] The first processing module 701 is used to detect the silicon wafer after wire cutting to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer;

[0124] A first determination module 702 is used to determine a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect;

[0125] The second processing module 703 is used to perform edge grinding on the silicon wafer according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after the edge grinding of the silicon wafer.

[0126] In some embodiments, the first processing module 701 includes:

[0127] A first processing unit is used to scan the surface of the silicon wafer after the wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer;

[0128] The second processing unit is used to obtain the position information and size information of the edge collapse defect on the surface of the silicon wafer according to the reflection intensity.

[0129] In some embodiments, the first processing unit is specifically configured to:

[0130] Controlling the silicon wafer to rotate;

[0131] During the rotation of the silicon wafer, the laser beam is controlled to move radially from the center of the surface of the wire-cut silicon wafer to the edge of the surface of the wire-cut silicon wafer to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer.

[0132] In some embodiments, the first determining module 702 includes:

[0133] A first determining unit is used to determine a first position coordinate on the edge collapse defect that is closest to the surface center of the silicon wafer after wire cutting according to the position information and the size information;

[0134] The second determining unit is used to determine a grinding center for edge grinding of the silicon wafer according to the first position coordinates.

[0135] In some embodiments, the second determining unit is specifically configured to:

[0136] When the number of the edge collapse defects is two, obtaining a first position coordinate corresponding to a first edge collapse defect of the two edge collapse defects and a first position coordinate corresponding to a second edge collapse defect of the two edge collapse defects;

[0137] Determine a first preselected center coordinate according to a first position coordinate corresponding to the first edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0138] Determine a second preselected center coordinate according to a first position coordinate corresponding to the second edge collapse defect and a surface radius of the silicon wafer after wire cutting;

[0139] A grinding center for edge grinding of the silicon wafer is determined according to the first preselected center coordinates and the second preselected center coordinates.

[0140] In some embodiments, the second determining unit is specifically configured to:

[0141] When the number of the edge collapse defects is greater than or equal to 3, determining a third edge collapse defect, a fourth edge collapse defect, and a central edge collapse defect among the edge collapse defects according to the position information and the size information;

[0142] Obtaining a first position coordinate corresponding to the third edge chipping defect, a first position coordinate corresponding to the fourth edge chipping defect, and a first position coordinate corresponding to the central edge chipping defect;

[0143] The grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates corresponding to the third edge chipping defect, the first position coordinates corresponding to the fourth edge chipping defect, and the first position coordinates corresponding to the central edge chipping defect.

[0144] In some embodiments, the second determining unit is specifically configured to:

[0145] Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the clockwise direction along the circumference of the silicon wafer is the third edge collapse defect;

[0146] Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the counterclockwise direction along the circumference of the silicon wafer is the fourth edge collapse defect;

[0147] Among the edge chipping defects, the edge chipping defect farthest from the notch of the silicon wafer along the circumferential direction of the silicon wafer is determined as the central edge chipping defect.

[0148] In some embodiments, the second determining unit is specifically configured to:

[0149] Generating a first line segment between the first position coordinate corresponding to the third edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0150] Generating a second line segment between the first position coordinate corresponding to the fourth edge chipping defect and the first position coordinate corresponding to the central edge chipping defect;

[0151] The intersection of the perpendicular bisector of the first line segment and the perpendicular bisector of the second line segment is used as a grinding center for edge grinding of the silicon wafer.

[0152] In some embodiments, the second processing module 703 includes:

[0153] A third processing unit is used to determine the coordinates of a second position on the edge chipping defect that is closest to the grinding center according to the position information and the size information;

[0154] The fourth processing unit is used to perform edge grinding on the silicon wafer according to the grinding center and the target radius when the distance between the second position coordinate and the grinding center is greater than the target radius.

[0155] It should be noted that the silicon wafer edge grinding device provided in the embodiment of the present invention is a device capable of executing the above-mentioned silicon wafer edge grinding method. All embodiments of the above-mentioned silicon wafer edge grinding method are applicable to the device and can achieve the same or similar technical effects.

[0156] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for grinding a silicon wafer edge, characterized in that: include: Detecting the silicon wafer after wire cutting to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer; Determining a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect; The edge of the silicon wafer is ground according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after the edge of the silicon wafer is ground.

2. The method according to claim 1, characterized in that The silicon wafer after wire cutting is inspected to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer, including: Scanning the surface of the silicon wafer after the wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer; According to the reflection intensity, the position information and size information of the edge collapse defect on the surface of the silicon wafer are obtained.

3. The method according to claim 2, characterized in that Scanning the surface of the silicon wafer after the wire cutting with a laser beam to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer includes: Controlling the silicon wafer to rotate; During the rotation of the silicon wafer, the laser beam is controlled to move radially from the center of the surface of the wire-cut silicon wafer to the edge of the surface of the wire-cut silicon wafer to obtain the reflection intensity of the laser beam at different positions on the surface of the silicon wafer.

4. The method according to claim 1, characterized in that: Determining a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect includes: Determine, according to the position information and the size information, a first position coordinate on the edge collapse defect that is closest to the center of the surface of the silicon wafer after wire cutting; A grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates.

5. The method according to claim 4, characterized in that Determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes: When the number of the edge collapse defects is two, obtaining a first position coordinate corresponding to a first edge collapse defect of the two edge collapse defects and a first position coordinate corresponding to a second edge collapse defect of the two edge collapse defects; Determining a first preselected center coordinate according to a first position coordinate corresponding to the first edge collapse defect and a surface radius of the silicon wafer after wire cutting; Determine a second preselected center coordinate according to a first position coordinate corresponding to the second edge collapse defect and a surface radius of the silicon wafer after wire cutting; A grinding center for edge grinding of the silicon wafer is determined according to the first preselected center coordinates and the second preselected center coordinates.

6. The method according to claim 4, characterized in that Determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates includes: When the number of the edge collapse defects is greater than or equal to 3, determining a third edge collapse defect, a fourth edge collapse defect, and a central edge collapse defect among the edge collapse defects according to the position information and the size information; Obtaining a first position coordinate corresponding to the third edge chipping defect, a first position coordinate corresponding to the fourth edge chipping defect, and a first position coordinate corresponding to the central edge chipping defect; The grinding center for edge grinding of the silicon wafer is determined according to the first position coordinates corresponding to the third edge chipping defect, the first position coordinates corresponding to the fourth edge chipping defect, and the first position coordinates corresponding to the central edge chipping defect.

7. The method according to claim 6, characterized in that Determining the third edge collapse defect, the fourth edge collapse defect and the central edge collapse defect among the edge collapse defects according to the position information and the size information, comprising: Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the clockwise direction along the circumference of the silicon wafer is the third edge collapse defect; Determine that among the edge collapse defects, the edge collapse defect closest to the notch of the silicon wafer in the counterclockwise direction along the circumference of the silicon wafer is the fourth edge collapse defect; Among the edge chipping defects, the edge chipping defect farthest from the notch of the silicon wafer along the circumferential direction of the silicon wafer is determined as the central edge chipping defect.

8. The method according to claim 6, characterized in that Determining a grinding center for edge grinding of the silicon wafer according to the first position coordinates corresponding to the third edge collapse defect, the first position coordinates corresponding to the fourth edge collapse defect, and the first position coordinates corresponding to the central edge collapse defect, includes: Generating a first line segment between the first position coordinate corresponding to the third edge chipping defect and the first position coordinate corresponding to the central edge chipping defect; Generating a second line segment between the first position coordinate corresponding to the fourth edge chipping defect and the first position coordinate corresponding to the central edge chipping defect; The intersection of the perpendicular bisector of the first line segment and the perpendicular bisector of the second line segment is used as a grinding center for edge grinding of the silicon wafer.

9. The method according to claim 1, characterized in that: The edge of the silicon wafer is ground according to the grinding center and the target radius, including: Determine, according to the position information and the size information, a second position coordinate on the chipping defect that is closest to the grinding center; When the distance between the second position coordinate and the grinding center is greater than the target radius, edge grinding is performed on the silicon wafer according to the grinding center and the target radius.

10. A silicon wafer edge grinding device, characterized in that: include: The first processing module is used to detect the silicon wafer after wire cutting to obtain the position information and size information of the edge collapse defect in the edge area of ​​the silicon wafer; A first determination module is used to determine a grinding center for edge grinding of the silicon wafer according to the position information and size information of the edge collapse defect; The second processing module is used to perform edge grinding on the silicon wafer according to the grinding center and the target radius, wherein the target radius is the radius of the silicon wafer after the edge grinding of the silicon wafer.

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