Wafer cutting channel defect detection method and device

Abstract

The invention discloses a wafer cutting channel defect detection method and device, and the method comprises the steps: photographing the front surface and the back surface of a cut cutting channel, detecting whether the cut defects exist in an obtained first photographing image of the front surface and a second photographing image of the back surface, and when the cutting abnormality is judged to occur, judging whether the cut defects exist or not. Photographing the cutting surface of the cutting channel at the abnormal position so as to further confirm the influence caused by the abnormality on the obtained third photographed image of the cutting surface; before photographing, optical amplification elements are arranged on the front face, the back face and the cutting face of the cutting channel respectively, then photographing is carried out, and amplified images formed by the front face, the back face and the cutting face of the cutting channel through the optical amplification elements are correspondingly displayed in a first photographed image, a second photographed image and a third photographed image. According to the invention, the detection area during photographing can be saved, the detection speed is improved, and rapid judgment is facilitated, so that the detection efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor processing technology, and in particular to a wafer sawing path defect detection method and device. Background Art

[0002] In the semiconductor chip packaging process, the chip needs to be cut, and the cutting process is carried out in the cutting lane. As the chip size continues to shrink, the size of the cutting lane between chips is also gradually reduced. The mechanical force of cutting may cause tiny cracks to form at the edge of the cutting lane. The tiny cracks caused by the cutting process will affect the reliability of the product. During the cutting process, the cracks may even destroy the sealing ring between the chip and the cutting lane. When the cracks eventually enter the inside of the chip, it will cause damage to the chip. Therefore, it is necessary to detect the cutting lane after cutting.

[0003] Currently, the main method for defect detection of cutting paths is manual visual inspection, which involves visually inspecting the front of the cutting path and manually turning it over to inspect the back of the cutting path. However, it is difficult to inspect the cross section of the cutting path by visual inspection, which results in some tiny cracks not being discovered in time during daily visual inspection, causing functional failure in the terminal product and resulting in greater losses. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects in the prior art and to provide a method and device for detecting wafer sawing line defects.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] The present invention provides a wafer sawing line defect detection method, comprising:

[0007] Taking photos of the front and back sides of the cutting path after cutting, detecting whether there are post-cutting defects in the obtained first front photographic image and the second back photographic image, and taking photos of the cutting surface of the cutting path at the abnormality when it is determined that a cutting abnormality occurs, so as to further confirm the influence of the abnormality in the obtained third photographic image of the cutting surface;

[0008] Before taking photos, optical magnifying elements are respectively arranged on the front side, the back side and the cutting surface of the cutting path, and then photos are taken, so that the magnified images of the front side, the back side and the cutting surface of the cutting path formed by the optical magnifying elements are correspondingly displayed in the first to third photographed images.

[0009] Furthermore, it also includes: taking a photo of the front side of the cutting road before cutting, and detecting whether the fourth photographed image of the front side has any pre-cutting defects; wherein, before taking the photo, the optical magnifying element is first arranged above the front side of the cutting road, and then taking the photo, so that the front side of the cutting road before cutting is displayed in the fourth photographed image through the magnified image formed by the optical magnifying element.

[0010] Furthermore, before photographing the front side of the cutting path, a plurality of adjacent cutting path detection areas are divided on the front side of the wafer according to the orthogonal direction of the cutting path, and each cutting path detection area is marked, and then each cutting path detection area is scanned and photographed along the direction of the cutting path and in a certain marking order; when photographing the back side of the cutting path, the back side of the wafer corresponding to the position of each cutting path detection area is scanned and photographed in the same order as when photographing the front side; and / or, when photographing the cutting surface, the position of the cutting surface to be photographed is determined according to the mark of the cutting path detection area where the abnormality is located; and / or, when scanning and photographing, the optical magnifying element is moved and set to a corresponding position as the photographing position changes.

[0011] Furthermore, the dicing lane detection area is divided and marked according to basic information of the wafer.

[0012] Furthermore, the basic information includes the size of the exposure unit and the position and number of cross marks. When the cutting path detection area is divided, the size of the cutting path detection area is made consistent with the size of the exposure unit, and the position of each cross mark on the cutting path is numbered according to the wafer notch position to mark each cutting path detection area.

[0013] Furthermore, according to the cross mark number, the wafer is divided into two semicircular areas, and the front and back sides of the two semicircular areas are scanned and photographed simultaneously. When scanning and photographing, each cutting road detection area on each semicircular area is photographed one by one, or multiple cutting road detection areas on each semicircular area are photographed in parallel under different shooting fields of view.

[0014] Furthermore, the optical amplifying element with a corresponding magnification is selected according to the size of the cutting path.

[0015] Furthermore, the optical magnifying element includes a rectangular magnifying glass. Before taking pictures, the magnifying glass is arranged along the direction of the cutting road, and the magnifying glass completely covers the cutting road in the shooting field of view, wherein the width of the magnifying glass in the vertical direction of the cutting road direction is one quarter to one half of the length of the cutting road detection area in this direction.

[0016] Furthermore, by establishing an image library, the first to fourth photographic images taken for the same cutting road detection area are merged and stored, and by retrieving the images, the cutting road defects before and after cutting are compared and confirmed.

[0017] Furthermore, by comparing the size of the post-cutting defect appearing in the first photographed image and the second photographed image with a threshold, when the size of the post-cutting defect exceeds the threshold, it is determined that a cutting abnormality occurs.

[0018] The present invention also provides a wafer sawing road defect detection device, comprising:

[0019] A stage for placing wafers;

[0020] A camera is arranged above the platform;

[0021] Optical magnification element;

[0022] A control module, used to control the camera to take photos of the front and back sides of the cut lanes on the wafer placed on the stage after cutting, so as to detect whether there are post-cutting defects in the obtained first front photographic image and the second back photographic image, and when it is determined that a cutting abnormality occurs, to control the camera to take photos of the cut surface of the cut lane at the abnormality, so as to further confirm the impact of the abnormality on the obtained third photographic image of the cut surface;

[0023] Among them, by respectively arranging the optical magnifying elements on the front side, the back side and the top of the cutting surface of the cutting path before taking pictures, and then controlling the camera to take pictures through the control module, the magnified images of the front side, the back side and the cutting surface of the cutting path formed by the optical magnifying elements are correspondingly displayed in the first to third photographed images.

[0024] Furthermore, the control module is also used to control the camera to take a picture of the front side of the cutting path before cutting, so as to detect whether there are pre-cutting defects in the fourth front photographed image obtained; wherein, by setting the optical magnifying element above the front side of the cutting path before taking the picture, and then controlling the camera to take the picture through the control module, the front side of the cutting path before cutting is magnified by the optical magnifying element and displayed in the fourth photographed image.

[0025] Furthermore, before taking a picture of the front side of the cutting path, the control module controls the camera along the direction of the cutting path, and scans and photographs each of the cutting path detection areas in a certain marking order according to a plurality of cutting path detection areas that are adjacent and marked in sequence and divided on the front side of the wafer according to the orthogonal direction of the cutting path; when taking a picture of the back side of the cutting path, the control module controls the camera to scan and photograph the back side of the wafer corresponding to the position of each cutting path detection area in the same order as when taking a picture of the front side; and / or, when taking a picture of the cutting surface, the control module determines the position of the cutting surface to be photographed according to the mark of the cutting path detection area where the abnormality is located; and / or, the optical magnifying element is provided on the camera and is located in the shooting field of view of the camera. When scanning and photographing, the optical magnifying element moves and is set to a position corresponding to the change of the shooting position of the camera.

[0026] Furthermore, the wafer is divided into two semicircular areas, and one or more cameras are respectively arranged above the two semicircular areas, so as to simultaneously scan and photograph the front and back sides of the two semicircular areas under the control of the control module; wherein, when one camera is respectively arranged above the two semicircular areas, each cutting road detection area on each semicircular area is photographed one by one during scanning and photographing, and when multiple cameras are respectively arranged above the two semicircular areas, multiple cutting road detection areas on each semicircular area are photographed in parallel under different shooting fields of view during scanning and photographing.

[0027] Furthermore, the magnification of the optical magnifying element is selected according to the size of the cutting path.

[0028] Furthermore, the optical magnifying element includes a rectangular magnifying glass, which is arranged along the direction of the cutting road before taking pictures, and the magnifying glass completely covers the cutting road in the shooting field of view, wherein the width of the magnifying glass in the vertical direction of the cutting road direction is one quarter to one half of the length of the cutting road detection area in this direction.

[0029] Furthermore, it also includes: an image library module, which establishes an image library for merging and storing the first to fourth photographic images taken for the same cutting road detection area, and the control module retrieves the images stored in the image library for comparison and confirmation of cutting road defects before and after cutting.

[0030] It can be seen from the above technical scheme that the present invention detects whether there are cutting defects by taking pictures of the front side, back side and cutting surface of the cutting path after cutting, and based on the principle of a magnifying glass, before taking pictures, optical magnifying elements are respectively set on the front side, back side and cutting surface of the cutting path, and then taking pictures, so that the front side, back side and cutting surface of the cutting path are magnified by the optical magnifying elements and displayed in the corresponding photographed image. It can not only effectively reflect the clear magnified image of the cutting path to be inspected, but also save the detection area during taking pictures and improve the detection speed by setting the magnification of the optical magnifying element. At the same time, it also makes the image clearer, which is convenient for intuitive detection of the cutting status, can quickly judge and mark abnormal images, improve detection efficiency, and provide guidance for optimizing the cutting method and improving the yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The figure is a flow chart of a wafer sawing line defect detection method according to a preferred embodiment of the present invention.

[0032] Figure 2 The figure is a schematic diagram of a cutting lane detection area division method according to a preferred embodiment of the present invention.

[0033] Figure 3 The figure is a schematic diagram of the display state of the cutting lane detection area in the shooting field of view when no magnifying glass is provided according to a preferred embodiment of the present invention.

[0034] Figure 4 It is a schematic diagram of the display state of the cutting lane detection area in the shooting field of view when a magnifying glass is provided according to a preferred embodiment of the present invention.

[0035] Figure 5 The figure is a schematic structural diagram of a wafer sawing line defect detection device according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not 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. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0037] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0038] A wafer sawing line defect detection method of the present invention comprises:

[0039] Taking photos of the front and back sides of the cutting lane after cutting, and detecting whether there are post-cutting defects in the obtained first front photographic image and the second back photographic image, and taking photos of the cutting surface of the cutting lane at the abnormality when it is determined that cutting abnormality occurs, so as to further confirm the influence of the abnormality in the obtained third photographic image of the cutting surface;

[0040] Before taking pictures, optical magnifying elements are respectively arranged on the front side, back side and above the cutting surface of the cutting path, and then pictures are taken, so that the magnified images of the front side, back side and cutting surface of the cutting path formed by the optical magnifying elements are correspondingly displayed in the first to third photographed images.

[0041] refer to Figure 1 In some embodiments, a wafer dicing defect detection method of the present invention comprises the following steps:

[0042] Step S1: dividing a scribe line detection area on the front side of the wafer.

[0043] like Figure 2 As shown, the front side of the wafer 100 to be inspected has a plurality of cutting lanes 101 arranged vertically and horizontally for dividing the die. The exposure unit 102 during photolithography includes one or more chips. First, according to the orthogonal direction of the cutting lanes 101, a plurality of sequentially adjacent cutting lane inspection areas 20 ( Figure 2 Only part of the cutting road detection area 20 is shown in FIG. 1 , and each cutting road detection area 20 is marked.

[0044] In some embodiments, the scribe line detection area 20 is divided and marked according to basic information of the wafer 100 .

[0045] Further, the basic information includes the size of the exposure unit 102 and the cross mark set on the cutting road 101 (refer to Figure 3 When dividing the cutting lane detection area 20, the cutting lane detection area is made consistent with the size of the exposure unit 102 during photolithography. And according to the position of the notch 103 on the wafer 100, the position of each cross mark on the cutting lane 101 is numbered to mark each cutting lane detection area 20.

[0046] In one example, the size of the cutting road detection area 20 can be made consistent with the size of the exposure unit 102, and the cutting road detection area 20 can be arranged around the intersection of the cutting road 101, such as Figure 2 As shown. That is, the cutting road detection area 20 needs to be staggered with the position of the exposure unit 102 formed by the mask on the wafer 100, so as to effectively take pictures of the cutting road 101 located between adjacent exposure units 102. At the same time, by numbering the position of each cross mark set on the cutting road 101 according to the relative position between the notch 103, the unique marking and identification of the position of each cutting road detection area 20 is realized.

[0047] Step S2: Scan and photograph each cutting road detection area 20 to obtain a front photographic image, and when photographing, preset an optical magnifying element above the front of the cutting road 101 to be photographed.

[0048] like Figure 2 As shown, each scribe line detection area 20 located on the front side of the wafer 100 can be automatically scanned and photographed by a photographing unit, such as a camera, disposed above the surface of the wafer 100. The size of the photographing field of the camera is made to correspond to the size and position of the scribe line detection area 20, so that when taking pictures, one scribe line detection area 20 can be completely photographed.

[0049] In some embodiments, photographing the front side of the wafer 100 includes photographing the front side of the scribe line 101 before cutting and photographing the front side of the scribe line 101 after cutting.

[0050] When photographing the front side of the cutting road 101 before cutting, firstly, according to the mark of the cutting road detection area 20, and along the direction of the cutting road 101 (for example, Figure 2 The scanning path of the camera is set according to a certain marking sequence. An optical magnifying element is set above the front of the cutting path 101 facing the camera (refer to Figure 4 ), and then scan and photograph each cutting road detection area 20, so that the front of the cutting road 101 is magnified by the optical magnifying element to form an enlarged image, and the area around the optical magnifying element that has not been magnified is simultaneously displayed in the front photographed image before cutting (the fourth photographed image). In this way, the front photographed image before cutting containing the enlarged image of the cutting road 101 corresponding to each cutting road detection area 20 is obtained.

[0051] When scanning and photographing, the optical magnifying element is moved and set to a corresponding position as the photographing position changes, that is, the optical magnifying element is moved and stopped synchronously with the camera.

[0052] In some embodiments, the optical magnifying element may be a magnifying glass, for example, a rectangular magnifying glass (see Figure 4 ).

[0053] like Figure 3As shown, it shows the shape of the scribe line detection area 20 appearing in the camera's shooting field of view 30. The shooting field of view 30 shows two crisscrossing scribe lines 101 located in one scribe line detection area 20, cross marks 104 set on the scribe lines 101, and the relative shapes of the chips 105 separated by the scribe lines 101.

[0054] like Figure 4 As shown in FIG. 4 , it shows the shape of the cutting road detection area 20 appearing in the shooting field 30 of the camera after placing an optical magnifying element 40, such as a rectangular magnifying glass 401 (represented by a gray area). Figure 3 In comparison, after the cutting road 101 located below the magnifying glass 401 is magnified, the magnified image is displayed through the magnifying glass 401 (the cross mark 104 on the cutting road 101 located below the magnifying glass 401, and the part of the chip 105 located below the magnifying glass 401, are also displayed as magnified images through the magnifying glass 401), and are displayed in the front photographic image before cutting (the fourth photographic image) at the same time as the non-magnified area around the magnifying glass 401.

[0055] By taking pictures and recording the front side of the cutting path 101 before cutting, the purpose is to detect whether there are defects caused by the previous process before cutting, that is, pre-cutting defects, and it can be used as a basis for evaluating the impact on cutting.

[0056] After that, after the wafer 100 is cut by the cutting road 101, the front side of the cut cutting road 101 can be photographed for detection. Similarly, according to the mark of the cutting road detection area 20, the scanning path of the camera is set, and it is consistent with the scanning path when taking pictures before cutting, so as to facilitate subsequent image comparison. A rectangular magnifying glass 401 is also set above the front side of the cut cutting road 101 facing the camera, and then pictures are taken, so that the front side of the cut cutting road 101 after cutting is magnified by the magnifying glass 401 to form an enlarged image, and the area around the magnifying glass 401 that has not been magnified is simultaneously displayed in the front side photographed image after cutting (the first photographed image).

[0057] Before and after the magnifying glass 401 is placed, the different sizes and shapes of the cut cutting road 101 appearing in the cutting road detection area 20 in the shooting field of view 30 of the camera can be referred to Figure 3-Figure 4 And the above description of the situation before cutting should be understood.

[0058] Therefore, compared with the conventional method of performing image detection by photographing, under the condition that the shooting field of view 30 (detection area) has the same area, the method of the present invention can be used to set a magnifying glass 401 in the shooting field of view 30 to obtain an enlarged image of the cutting road 101 (detection object) that is locally and specifically magnified, so that the area of ​​the cutting road 101 that needs to be observed is highlighted and clearer, thereby saving the detection area when taking pictures, improving the detection speed, facilitating intuitive detection of the cutting status, and quickly judging and marking abnormal images, thereby improving detection efficiency.

[0059] The purpose of taking photos and recording the front side of the dicing road 101 after dicing is to detect whether the dicing process causes defects on the front side of the wafer 100 and the extent (size) of the defects.

[0060] Step S3: In the same order as step S2, the back side of the wafer 100 corresponding to each cutting line detection area 20 is scanned and photographed to obtain a back side photographic image, and when photographing, an optical magnifying element 40 is preset above the back side of the cutting line 101 to be photographed.

[0061] According to the same scanning and photographing sequence as that for photographing the front side of the cut scribe line 101, the back side of the wafer 100 corresponding to the positions of the cut scribe line detection areas 20 on the front side is scanned and photographed to obtain a back side photographed image (a second photographed image) for subsequent image comparison. Similarly, a rectangular magnifying glass 401 is set above the back side of the cut scribe line 101 facing the camera, and then photographing is performed, so that the back side of the cut scribe line 101 after cutting is magnified by the magnifying glass 401 to form an enlarged image, and the area around the magnifying glass 401 that has not been magnified is simultaneously displayed in the back side photographed image (the second photographed image) after cutting.

[0062] Before and after the magnifying glass 401 is placed, the different size and shape features of the back of the cut cutting road 101 appearing in the camera's shooting field of view 30 can be referred to Figure 3-Figure 4 As well as the above description of the front side of the cutting road 101 after cutting, it is understood and no longer shown in the form of diagrams.

[0063] By taking photos and recording the back side of the dicing road 101 after dicing, the purpose is to detect whether the dicing process causes defects on the back side of the wafer 100 and the extent (size) of the defects.

[0064] Step S4: Confirm the front photographic image and the back photographic image, and when it is determined that a cutting abnormality occurs, take a photograph of the cutting surface of the cutting path 101 at the abnormal location to obtain a photographic image of the cutting surface for further confirmation, and when taking pictures, preset an optical magnifying element 40 above the cutting surface to be photographed.

[0065] After obtaining the front and back photographic images, the front and back photographic images can be confirmed and compared to determine whether the cutting is qualified. The position of the found cutting defect (such as a crack or a fissure) on the wafer 100 can also be determined according to the number of the cross mark 104.

[0066] In some embodiments, by comparing the size of the post-cutting defect appearing in the front photographic image and the back photographic image (for example, the width of a crack or fissure) with a threshold, when the size of the post-cutting defect appearing in the front photographic image or the back photographic image exceeds the threshold, it is determined that a cutting abnormality has occurred.

[0067] In some embodiments, the threshold is 10 micrometers. When the size of the defect after cutting exceeds 10 micrometers, it is determined that cutting abnormality occurs.

[0068] When it is determined that a cutting abnormality occurs, it is necessary to further take a photo of the cutting surface of the cutting path 101 at the abnormal location to obtain a photo image of the cutting surface (the third photo image) for further confirmation to determine whether there are hidden defects caused by stress on the cutting surface. When taking photos, a rectangular magnifying glass 401 is also preset above the cutting surface to be photographed.

[0069] When photographing the cut surface, the position of the cut surface to be photographed is determined based on the mark of the cut path detection area 20 where the abnormality is located and the structure of the chip. The cut surface of the wafer 100 is rotated after cutting and a magnifying glass 401 is placed above the cut surface, and the cut surface where the abnormality is located is photographed and the abnormal image is recorded.

[0070] In some embodiments, the front side photographic image, the back side photographic image and the cut side photographic image are confirmed and compared by manual visual inspection.

[0071] In some other embodiments, the front side photographic image, the back side photographic image and the cut side photographic image are automatically confirmed and compared through machine vision technology.

[0072] In some embodiments, the wafer 100 is divided into two semicircular areas according to the numbering of the cross mark 104, and the front side of the two semicircular areas are scanned and photographed simultaneously, and the back side of the two semicircular areas are scanned and photographed simultaneously along the same path.

[0073] Furthermore, when scanning and photographing, each cutting road detection area 20 on each semicircular area is photographed one by one. That is, a camera is set on each of the two semicircular areas, and the two cameras are used to simultaneously photograph each cutting road detection area 20 on the respective semicircular areas, so as to improve the detection efficiency.

[0074] Alternatively, when scanning and photographing, multiple cutting lane detection areas 20 on each semicircular area are photographed in parallel under different photographing fields of view 30. That is, a camera array consisting of multiple cameras is respectively set on the two semicircular areas, and the corresponding number of cutting lane detection areas 20 on the respective semicircular areas are photographed simultaneously through the two camera arrays, so as to further improve the detection efficiency.

[0075] In some embodiments, according to the size of the cutting road 101, a magnifying glass 401 (optical magnifying element 40) with a suitable magnification is selected to take pictures, so as to save the detection surface, improve the detection speed, and make the image clearer.

[0076] In some embodiments, before taking pictures, the rectangular magnifying glass 401 is arranged along the direction of the cutting road 101, and the length direction of the magnifying glass 401 corresponds to the direction of the cutting road 101 in the shooting field of view 30, such as Figure 4 And, the magnifying glass 401 completely covers the cutting road 101 in the shooting field of view 30. The width of the magnifying glass 401 is one quarter to one half of the length of the cutting road detection area 20 in the vertical direction.

[0077] In some embodiments, by establishing an image library, the front side photographic images, back side photographic images and cutting surface photographic images taken for the same cutting road detection area 20 are merged and stored, so as to store all photographic images corresponding to each cutting road detection area 20. And by querying the image library and retrieving images, the defects of the cutting road 101 before and after cutting are compared and confirmed, and the structural layer where the abnormality is located is marked and determined, so as to guide the process optimization on the line, optimize the product cutting method, and improve the product yield.

[0078] The following is a further detailed description of a wafer sawing line defect detection device of the present invention through specific implementation modes and in combination with the accompanying drawings.

[0079] refer to Figure 5 Combined with reference Figure 2-Figure 4 The wafer dicing line defect detection device of the present invention can be used to implement the wafer dicing line defect detection method of the present invention. The wafer dicing line defect detection device of the present invention includes a stage 10 , a camera 50 , an optical amplifying element 40 and a control module 80 .

[0080] The stage 10 is used to place the wafer 100 . The camera 50 is disposed above the stage 10 , and is used to take pictures of the wafer 100 . The camera 50 can move above the wafer 100 to scan and take pictures of the surface of the wafer 100 .

[0081] The control module 80 is connected to the camera 50 by signal, and is used to control the camera 50 to take pictures of the front and back sides of the cut road 101 on the wafer 100 placed on the stage 10, and obtain a first front photographic image and a second back photographic image, so as to detect whether there are post-cutting defects in the first front photographic image and the second back photographic image. When it is determined that a cutting abnormality occurs, the control module 80 is also used to control the camera 50 to take pictures of the cut surface of the cut road 101 at the abnormal location, and obtain a third cut surface photographic image, so as to further confirm the impact of the abnormality on the third cut surface photographic image.

[0082] Among them, by respectively setting optical magnifying elements 40 (such as magnifying glasses 401) on the front side, back side and above the cutting surface of the cutting road 101 before photographing, and then controlling the camera 50 to take pictures through the control module 80, the front side, back side and cutting surface of the cutting road 101 are magnified by the optical magnifying element 40 and are correspondingly displayed in the first photographed image to the third photographed image.

[0083] Furthermore, the control module 80 is also used to control the camera 50 to take a picture of the front of the cutting road 101 before cutting, and obtain a fourth front photographic image for detecting whether there are pre-cutting defects in the fourth photographic image. Among them, by arranging an optical magnifying element 40 (such as a magnifying glass 401) above the front of the cutting road 101 before taking a picture, and then controlling the camera 50 to take a picture through the control module 80, the front of the cutting road 101 before cutting is displayed in the fourth photographic image through the magnified image formed by the optical magnifying element 40.

[0084] In some embodiments, before taking pictures of the front side of the cutting road 101, the control module 80 controls the camera 50 to scan and take pictures of each cutting road detection area 20 along the direction of the cutting road 101 according to a certain marking order, based on a plurality of adjacent and marked cutting road detection areas 20 divided on the front side of the wafer 100 according to the orthogonal direction of the cutting road 101.

[0085] When photographing the back side of the dicing lane 101 , the control module 80 controls the camera 50 to scan and photograph the back side of the wafer 100 corresponding to the position of each dicing lane detection area 20 in the same order as when photographing the front side.

[0086] When taking a photo of the cutting surface, the control module 80 determines the position of the cutting surface to be photographed according to the mark of the cutting path detection area 20 where the abnormality is located.

[0087] In some embodiments, the optical magnifying element 40 includes a rectangular magnifying glass 401. Moreover, the magnifying glass 401 is disposed on the camera 50 and is located in the shooting field of view 30 of the camera 50.

[0088] In some embodiments, the magnifying glass 401 is mounted on the camera 50 via a bracket 60 , so that the mounted magnifying glass 401 is located directly below the shooting field of view 30 of the camera 50 .

[0089] When scanning and photographing, the magnifying glass 401 is placed close to the surface of the wafer 100 so that the magnified image of the cutting path 101 through the magnifying glass 401 is clearly reflected in the photographed image of the camera 50. In addition, the magnifying glass 401 moves and stops synchronously with the change of the photographing position of the camera 50.

[0090] In some embodiments, the wafer 100 is divided into two semicircular areas, and one or more cameras 50 are respectively arranged above the two semicircular areas, so as to simultaneously scan and photograph the front side of the two semicircular areas and simultaneously scan and photograph the back side of the two semicircular areas under the control of the control module 80. When one camera 50 is respectively arranged above the two semicircular areas, each cutting road detection area 20 on each semicircular area is photographed one by one during scanning and photographing. When multiple cameras 50 are respectively arranged above the two semicircular areas to form two camera 50 arrays, when scanning and photographing, the corresponding multiple cutting road detection areas 20 on each semicircular area are photographed in parallel under different shooting fields of view 30 corresponding to different cameras 50.

[0091] In some embodiments, the magnification of the magnifying glass 401 is selected according to the size of the cutting street 101 .

[0092] In some embodiments, the magnifying glass 401 is arranged along the direction of the cutting road 101, and the length direction of the rectangular magnifying glass 401 is arranged to correspond to the length direction of the cutting road 101 located in the shooting field of view 30 (cutting road detection area 20). Figure 4 As shown. Moreover, the magnifying glass 401 completely covers the cutting road 101 in the shooting field of view 30. The width of the magnifying glass 401 is one quarter to one half of the length of the cutting road detection area 20 in the vertical direction.

[0093] In some embodiments, the device further includes an image library module 90. The image library module 90 establishes an image library for merging and storing the first to fourth photographic images taken for the same cutting road detection area 20. The images stored in the image library are retrieved by the control module 80 for comparison and confirmation of defects of the cutting road 101 before and after cutting.

[0094] In some embodiments, the camera 50 is disposed on the transfer mechanism 70. The control module 80 controls the transfer mechanism 70 to enable the camera 50 to scan and take pictures along a set path.

[0095] In summary, the present invention detects whether there are cutting defects by taking photos of the front side, back side and cutting surface of the cutting road 101 after cutting, and based on the principle of a magnifying glass, before taking photos, an optical magnifying element 40 (magnifying glass 401) is respectively arranged on the front side, back side and cutting surface of the cutting road 101, and then taking photos, so that the magnified images formed by the optical magnifying element 40 on the front side, back side and cutting surface of the cutting road 101 are displayed in the corresponding photographed image, which can not only effectively reflect the clear magnified image of the cutting road 101 to be inspected, but also can save the detection area during taking photos and improve the detection speed by setting the magnification of the optical magnifying element 40, and also make the image clearer, which is convenient for intuitive detection of the cutting status, can quickly judge and mark abnormal images, improve detection efficiency, and can provide guidance for optimizing the cutting method and improving the yield.

[0096] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A wafer sawing line defect detection method, characterized in that: include: Taking photos of the front and back sides of the cutting path after cutting, detecting whether there are post-cutting defects in the obtained first front photographic image and the second back photographic image, and taking photos of the cutting surface of the cutting path at the abnormality when it is determined that a cutting abnormality occurs, so as to further confirm the influence of the abnormality in the obtained third photographic image of the cutting surface; Before taking photos, optical magnifying elements are respectively arranged on the front side, the back side and the cutting surface of the cutting path, and then photos are taken, so that the magnified images of the front side, the back side and the cutting surface of the cutting path formed by the optical magnifying elements are correspondingly displayed in the first to third photographed images.

2. The wafer dicing defect detection method according to claim 1, characterized in that: Also includes: The front side of the cutting path before cutting is photographed, and the fourth photographed image of the front side obtained is inspected for pre-cutting defects; wherein, before photographing, the optical magnifying element is firstly arranged above the front side of the cutting path, and then photographing is performed, so that the front side of the cutting path before cutting is displayed in the fourth photographed image through the magnified image formed by the optical magnifying element.

3. The wafer dicing defect detection method according to claim 2, characterized in that: Before photographing the front side of the cutting path, first divide a plurality of sequentially adjacent cutting path detection areas on the front side of the wafer according to the orthogonal direction of the cutting path, and mark each of the cutting path detection areas, and then scan and photograph each of the cutting path detection areas along the direction of the cutting path and in a certain marking order; when photographing the back side of the cutting path, scan and photograph the back side of the wafer corresponding to the position of each of the cutting path detection areas in the same order as when photographing the front side; And / or, when photographing the cutting surface, the position of the cutting surface to be photographed is determined based on the mark of the cutting path detection area where the abnormality is located; and / or, when scanning and photographing, the optical magnifying element is moved and set to a corresponding position as the photographing position changes.

4. The wafer dicing defect detection method according to claim 3, characterized in that: The dicing lane detection area is divided and marked according to basic information of the wafer.

5. The wafer dicing defect detection method according to claim 4, characterized in that: The basic information includes the size of the exposure unit and the position and number of cross marks. When the cutting path detection area is divided, the size of the cutting path detection area is made consistent with the size of the exposure unit, and the position of each cross mark on the cutting path is numbered according to the wafer notch position to mark each cutting path detection area.

6. The wafer dicing defect detection method according to claim 5, characterized in that: According to the cross mark number, the wafer is divided into two semicircular areas, and the front and back sides of the two semicircular areas are scanned and photographed simultaneously. When scanning and photographing, each cutting path detection area on each semicircular area is photographed one by one, or multiple cutting path detection areas on each semicircular area are photographed in parallel under different shooting fields of view.

7. The wafer dicing defect detection method according to claim 1, characterized in that: According to the size of the cutting road, the optical magnification element with the corresponding magnification is selected.

8. The wafer dicing defect detection method according to claim 3, characterized in that: The optical magnifying element comprises a rectangular magnifying glass. Before taking pictures, the magnifying glass is arranged along the direction of the cutting road and completely covers the cutting road in the shooting field of view, wherein the width of the magnifying glass in the vertical direction of the cutting road direction is one quarter to one half of the length of the cutting road detection area in this direction.

9. The wafer dicing defect detection method according to claim 3, characterized in that: By establishing an image library, the first to fourth photographic images taken for the same cutting road detection area are merged and stored, and by retrieving the images, the cutting road defects before and after cutting are compared and confirmed.

10. The wafer dicing defect detection method according to claim 1, characterized in that: By comparing the size of the post-cutting defect appearing in the first photographed image and the second photographed image with a threshold, when the size of the post-cutting defect exceeds the threshold, it is determined that a cutting abnormality occurs.

11. A wafer sawing line defect detection device, characterized in that: include: A stage for placing wafers; A camera is arranged above the platform; Optical magnification element; A control module, used to control the camera to take photos of the front and back sides of the cut lanes on the wafer placed on the stage after cutting, so as to detect whether there are post-cutting defects in the obtained first front photographic image and the second back photographic image, and when it is determined that a cutting abnormality occurs, to control the camera to take photos of the cut surface of the cut lane at the abnormality, so as to further confirm the impact of the abnormality on the obtained third photographic image of the cut surface; Among them, by respectively arranging the optical magnifying elements on the front side, the back side and the top of the cutting surface of the cutting path before taking pictures, and then controlling the camera to take pictures through the control module, the magnified images of the front side, the back side and the cutting surface of the cutting path formed by the optical magnifying elements are correspondingly displayed in the first to third photographed images.

12. The wafer dicing line defect detection device according to claim 11, characterized in that: The control module is also used to control the camera to take a picture of the front side of the cutting path before cutting, so as to detect whether the fourth front photographed image obtained has pre-cutting defects; wherein, by setting the optical magnifying element above the front side of the cutting path before taking the picture, and then controlling the camera to take the picture through the control module, the front side of the cutting path before cutting is displayed in the fourth photographed image through the enlarged image formed by the optical magnifying element.

13. The wafer dicing line defect detection device according to claim 12, characterized in that: Before taking a picture of the front side of the cutting path, the control module controls the camera to scan and take a picture of each cutting path detection area along the direction of the cutting path according to a certain marking sequence, based on a plurality of cutting path detection areas that are sequentially adjacent and marked and divided on the front side of the wafer according to the orthogonal direction of the cutting path; when taking a picture of the back side of the cutting path, the control module controls the camera to scan and take a picture of the back side of the wafer corresponding to the position of each cutting path detection area in the same sequence as when taking a picture of the front side; And / or, when taking a picture of the cutting surface, the control module determines the position of the cutting surface to be photographed based on the mark of the cutting path detection area where the abnormality is located; and / or, the optical magnifying element is arranged on the camera and is located in the shooting field of view of the camera. When scanning and taking pictures, the optical magnifying element moves and sets its position accordingly as the shooting position of the camera changes.

14. The wafer dicing line defect detection device according to claim 13, characterized in that: The wafer is divided into two semicircular areas, and one or more cameras are respectively arranged above the two semicircular areas, so as to scan and photograph the front and back sides of the two semicircular areas at the same time under the control of the control module; wherein, when one camera is respectively arranged above the two semicircular areas, each cutting road detection area on each semicircular area is photographed one by one during scanning and photographing, and when multiple cameras are respectively arranged above the two semicircular areas, multiple cutting road detection areas on each semicircular area are photographed in parallel under different shooting fields of view during scanning and photographing.

15. The wafer dicing line defect detection device according to claim 11, characterized in that: The magnification of the optical magnifying element is selected according to the size of the cutting street.

16. The wafer dicing line defect detection device according to claim 13, characterized in that: The optical magnifying element comprises a rectangular magnifying glass, which is arranged along the direction of the cutting road before photographing, and the magnifying glass completely covers the cutting road in the photographing field of view, wherein the width of the magnifying glass in the vertical direction of the cutting road direction is one quarter to one half of the length of the cutting road detection area in this direction.

17. The wafer dicing line defect detection device according to claim 13, characterized in that: Also includes: An image library module is provided with an image library for merging and storing the first to fourth photographic images taken for the same cutting road detection area, and the images stored in the image library are retrieved through the control module for comparison and confirmation of cutting road defects before and after cutting.

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