Wafer edge defect detection device

Abstract

The utility model belongs to the technical field of semiconductor equipment, and provides a wafer edge defect detection device which is used for wafer edge defect detection and comprises a bearing table top, a first camera shooting part, a rotating shaft and an image processing part, a wafer is placed on the upper surface of the bearing table top, and the first camera shooting part is located above the bearing table top and aligned with the wafer edge; the rotating shaft is connected to the lower surface of the bearing table top and can drive the bearing table top to rotate, and the image processing part is connected to the first camera shooting part and processes the received wafer edge image to generate a wafer profile diagram, and the obtained wafer profile diagram is compared with a wafer template diagram; according to the invention, the edge defect position of the wafer can be obtained, and the edge defect position is marked and stored, so that the detection efficiency and the detection accuracy of the wafer defect are effectively improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor equipment technology, and in particular to a wafer edge defect detection device. Background Art

[0002] Wafers are commonly used in the manufacture of integrated circuits and various semiconductor devices in semiconductor manufacturing. The wafer manufacturing process involves multiple processes, such as purification, growth, cutting, polishing, etc. During the processing of wafers, errors such as improper cutting operations, collisions, excessive wear, scratches, etc. may occur, resulting in the occurrence of various defects such as chipping. Among them, wafer chipping defects refer to unexpected missing or concave edges or surfaces of wafers. Wafer chipping defects can seriously affect the performance and reliability of devices. For example, chipping may make the device more susceptible to mechanical stress in the subsequent manufacturing process, thereby generating cracks. The presence of chipping will also affect the flatness of the wafer, thereby affecting subsequent semiconductor processing operations.

[0003] Currently, manual visual inspection is often used to detect chipped corners on wafer edges. However, manual inspection is inefficient and often leads to missed inspections due to factors such as visual errors, which affects the production process and can even cause wafer breakage. A large amount of manpower and material resources are required for cleaning and maintenance, which not only increases manufacturing costs and wastes human resources, but also reduces production efficiency. Utility Model Content

[0004] The purpose of this application is to provide a wafer edge defect detection device to solve the problems of low efficiency and low accuracy of wafer corner chipping detection in the prior art, and to improve the efficiency and accuracy of wafer corner chipping detection.

[0005] To achieve the above-mentioned and other related purposes, the present application provides a wafer edge defect detection device for wafer edge defect detection, comprising:

[0006] A carrying table having an upper surface and a lower surface opposite to each other, a wafer is placed on the upper surface of the carrying table, the wafer having a front surface and a back surface opposite to each other, the back surface being in contact with the carrying table;

[0007] A first camera unit is located above the carrying table, and the first camera unit is aligned with the edge of the wafer to obtain a wafer edge image of the front side of the wafer;

[0008] A rotating shaft connected to the lower surface of the carrying table to drive the carrying table to rotate around the axis of the rotating shaft;

[0009] The image processing unit is connected to the first camera unit to receive the wafer edge image and process the wafer edge image to generate a wafer contour image.

[0010] Optionally, the wafer, the carrying table and the rotation axis are coaxially arranged.

[0011] Optionally, the rotating shaft has a vacuum passage connected to the vacuum pumping pipeline, and the supporting table is provided with a plurality of first vacuum holes spaced apart from each other. The first vacuum holes are connected to the vacuum passage and have a first opening on the upper surface of the supporting table. The vacuum pumping pipeline allows the supporting table to adsorb the wafer through the first opening.

[0012] Optionally, in a top view of the supporting platform along its axial direction, the plurality of first openings are evenly distributed around the center of the supporting platform.

[0013] Optionally, a first groove is formed on the lower surface of the supporting table, the first groove is connected to the vacuum passage, and the first vacuum hole is connected to the first groove, so that the first vacuum hole is connected to the vacuum passage.

[0014] Optionally, the vacuum passage, the first groove and the rotating shaft are coaxially arranged, and the surface of the rotating shaft close to the supporting table completely covers the first groove.

[0015] Optionally, a second camera unit is further included, which is located below the supporting table and is aligned with the edge of the wafer to obtain a wafer edge image on the back side of the wafer.

[0016] Optionally, a cavity is further included, wherein a working chamber is formed in the cavity, and the first camera part, the second camera part and the supporting platform are all located in the working chamber.

[0017] Optionally, a supporting portion is further included, wherein the supporting portion includes a first support and a second support, wherein opposite ends of the first support are respectively connected to the side wall of the working chamber and the first camera portion to support the first camera portion, and opposite ends of the second support are respectively connected to the bottom surface of the working chamber and the second camera portion to support the second camera portion.

[0018] Optionally, a driving part is further included, which is located outside the working chamber, and one end of the rotating shaft away from the carrying table is connected to the driving part, so that the driving part drives the rotating shaft to rotate.

[0019] The wafer edge defect detection device provided in this application has at least the following beneficial effects:

[0020] The wafer is placed on the supporting table, and the supporting table is driven to rotate by the rotating shaft. The wafer edge image can be obtained by the first camera unit, and the wafer edge image is processed by the image processing unit to form a wafer contour map. By detecting and retaining the wafer contour map, the efficiency and accuracy of wafer defect detection are effectively improved; the upper surface of the supporting table has multiple first openings, and the multiple first openings are evenly arranged around the center of the supporting table, which can achieve effective adsorption of wafers of different thicknesses, thereby improving the applicability of the device; the supporting table is a transparent table, and the wafer contour map of the back of the wafer can be simultaneously formed by the second camera unit, further improving the detection efficiency and accuracy of wafer edge defects, and improving the detection effect of wafer edge defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 Shown is a structural schematic diagram of the wafer edge defect detection device provided in Example 1 of the present application.

[0023] Figure 2 Display as Figure 1 A top view of the rotation axis in the wafer edge defect inspection device is shown.

[0024] Figure 3 Display as Figure 1 The figure shows a schematic diagram of the structure of the vacuum passage in the wafer edge defect detection device.

[0025] Figure 4 Shown is a schematic structural diagram of the first opening on the upper surface of the supporting table provided in an optional embodiment of the first embodiment of the present application.

[0026] Figure 5 Shown is a structural schematic diagram of a first opening provided in another optional embodiment of the first embodiment of the present application.

[0027] Figure 6 Shown is a bottom view of the supporting table in the wafer edge defect detection device provided in Example 1 of the present application.

[0028] Figure 7 Display as Figure 6 The specific structural diagram of area M in the supporting platform is shown.

[0029] Figure 8Shown is a structural schematic diagram of a wafer edge defect detection device provided in an optional embodiment of the first embodiment of the present application.

[0030] Figure 9 Shown is a structural schematic diagram of the wafer edge defect detection device provided in Example 2 of the present application.

[0031] Reference numerals:

[0032] 1. Wafer; 2. Carrying table; 21. First vacuum hole; 211. First opening; 212. Second opening; 22. First groove; 3. Rotation axis; 31. Vacuum passage; 41. First camera unit; 42. Second camera unit; 5. Image processing unit; 6. Drive unit; 7. Support unit; 71. First support; 72. Second support; 8. Cavity; 81. Working chamber. DETAILED DESCRIPTION

[0033] To make the technical objectives, technical solutions, and technical effects of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Generally, the components of the embodiments of this application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but rather merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in this application without creative effort are within the scope of protection of this application. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance.

[0035] In the description of this application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0036] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. In addition, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in combination with the implementation or example are included in at least one implementation or example of this application. In this specification, the schematic representation of the above terms does not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more implementations or examples in a suitable scheme.

[0037] Example 1

[0038] This embodiment provides a wafer edge defect detection device for wafer edge defect detection, such as wafer edge chipping defect detection, referring to Figure 1 The wafer edge defect detection device of this embodiment includes a carrying table 2 , a rotating shaft 3 , a first camera unit 41 and an image processing unit 5 .

[0039] The carrying table 2 has an upper surface and a lower surface that are relatively set. The wafer 1 is placed on the upper surface of the carrying table 2. The wafer 1 has a front and a back surface that are relatively set. The back of the wafer 1 is in contact with the carrying table 2. Optionally, a membrane is applied to the front of the wafer 1 to protect the wafer 1 during the inspection process. The first camera unit 41 is located above the carrying table 2, and the first camera unit 41 is aligned with the edge of the wafer to obtain an image of the wafer edge on the front of the wafer 1. Optionally, the first camera unit 41 is an industrial camera. The rotating shaft 3 is connected to the lower surface of the carrying table 2 to drive the carrying table 2 to rotate around the axis of the rotating shaft 3. The image processing unit 5 is connected to the first camera unit 41 and can receive the image obtained by the first camera unit 41 and process the image to generate a wafer contour map. Optionally, the image processing unit 5 is communicatively connected to the first camera unit 41.

[0040] During use, the wafer 1 is placed on the supporting table 2, and the rotating shaft 3 drives the supporting table 2 to rotate around the axis of the rotating shaft 3. Every time the supporting table 2 rotates by a first angle, the first camera unit 41 obtains an image of the edge of the wafer. After the supporting table 2 rotates one circle, the first camera unit 41 transmits at least one image obtained to the image processing unit 5. The image processing unit 5 performs image stitching processing on the image obtained by the first camera unit 41 to form a wafer contour map, compares the wafer contour map with the wafer template map to obtain the edge defect position, marks the edge defect position and saves the wafer contour map with the marking. Optionally, after obtaining the wafer contour map of the front side of the wafer 1, the wafer 1 is turned upside down, and the above operation is repeated to obtain the wafer contour map of the back side of the wafer 1. The wafer contour map of the back side of the wafer 1 is compared with the wafer template map to obtain the edge defect position on the back side of the wafer 1, mark it and save the wafer contour map of the back side of the wafer 1 with the marking.

[0041] In an optional embodiment, the first angle can be, for example, 20°, 30°, 45°, 60° or 90°, etc. Optionally, the first angle is taken as 30°, and the first camera unit 41 obtains an image of the wafer edge every time the supporting table 2 rotates 30°. After the supporting table 2 rotates one circle, the first camera unit 41 obtains a total of 12 edge images of the front side of the wafer 1. The image processing unit 5 splices the 12 edge images to obtain a wafer contour image of the front side of the wafer 1.

[0042] In this embodiment, the supporting table 2, the wafer 1 placed on the supporting table 2 and the rotating axis 3 are arranged coaxially. When the supporting table 2 rotates, it can ensure that the first camera part 41 is always aligned with the edge of the wafer, thereby ensuring that the first camera part 41 can always obtain a clear image of the edge of the wafer, thereby improving the accuracy and efficiency of wafer defect detection.

[0043] In this embodiment, refer to Figure 2 A vacuum passage 31 is provided in the rotating shaft 3. The vacuum passage 31 extends along the axial direction of the rotating shaft 3 from the end of the rotating shaft 3 away from the supporting table 2 to the upper surface of the rotating shaft 3 and exposes the supporting table 2. The end of the vacuum passage 31 away from the rotating table is connected to the vacuum pumping line, wherein the upper surface of the rotating shaft 3 is the surface where the rotating shaft 3 contacts the supporting table 2. Figure 3 and Figure 4A plurality of first vacuum holes 21 are provided in the carrying table 2, and the plurality of first vacuum holes 21 are spaced apart from each other. The plurality of first vacuum holes 21 are interconnected with the vacuum passage 31, and the first vacuum hole 21 has a first opening 211 on the upper surface of the carrying table 2. After the wafer 1 is placed on the carrying table 2, it can completely cover the first opening 211, so that the vacuum pipeline can adsorb the wafer 1 through the first opening 211, thereby fixing the wafer 1 on the carrying table 2, ensuring that when the wafer edge defects are detected, the relative position of the wafer 1 and the carrying table 2 remains unchanged, thereby improving the working reliability of the wafer edge defect detection device and the accuracy of the detection results.

[0044] In an alternative embodiment, reference Figure 4 and Figure 5 In a top view of the support table 2 along its axial direction, the first openings 211 of the plurality of first vacuum holes 21 are evenly distributed around the center of the support table 2. The number of first openings 211 can be set accordingly based on actual needs, for example, it can be 3, 4, 6, or other suitable numbers. Optionally, the number of first openings 211 can be 3, and the three first openings 211 are evenly distributed circumferentially around the center of the support table 2; or the number of first openings 211 can be 9, wherein the three first openings 211 form a first group of openings, and the other six first openings 211 form a second group of openings, wherein the first group of openings are evenly distributed circumferentially around the center of the support table 2, and the second group of openings are located outside the first group of openings along the radial direction of the support table 2 and are evenly distributed circumferentially around the center of the support table 2.

[0045] By opening a plurality of first openings 211 spaced apart from each other on the upper surface of the supporting table 2 , thicker wafers and thinner wafers can be adsorbed simultaneously, thereby improving the applicability of the wafer edge defect detection device and ensuring the adsorption and fixing effect of the wafer 1 .

[0046] In this embodiment, refer to Figure 6 and Figure 7 A first groove 22 is provided in the lower surface of the supporting table 2, and the first groove 22 is connected to the vacuum passage 31 in the rotating shaft 3. A plurality of first vacuum holes 21 are connected to the first groove 22, so that the first vacuum holes 21 are connected to the vacuum passage 31 through the first groove 22.

[0047] In an alternative embodiment, the vacuum passage 31 and the first groove 22 are coaxially arranged with the rotating shaft 3, and the surface of the rotating shaft 3 on the side closest to the support table 2 completely covers the first groove 22, so that the rotating shaft 3 can support the support table 2 while the first groove 22 is connected to the vacuum passage 31. Optionally, the first vacuum hole 21 has a second opening 212 at one end away from the first opening 211. The second opening 212 is located on the sidewall of the first groove 22, and the first vacuum hole 21 is connected to the first groove 22 through the second opening 212.

[0048] In this embodiment, refer to Figure 8 The wafer edge defect detection device also includes a cavity 8, in which a working chamber 81 is formed. The first camera unit 41, the supporting table 2 and the wafer 1 placed on the supporting table 2 are all located in the working chamber 81. The working chamber 81 can provide a clean measurement space for the wafer 1 to prevent impurities in the air from contaminating the wafer 1.

[0049] In this embodiment, the wafer edge defect detection device also includes a driving unit 6, which is located outside the working chamber 81. The rotating shaft 3 extends to the outside of the working chamber 81 away from one end of the supporting table 2 and is connected to the driving unit 6. The driving unit 6 can drive the rotating shaft 3 to rotate. Optionally, the driving unit is a driving motor.

[0050] In this embodiment, the wafer edge defect detection device also includes a support part 7, which includes a first support 71. The opposite ends of the first support 71 are respectively connected to the side wall of the working chamber 81 and the first camera part 41. The first support 71 can support the first camera part 41 so that the relative position of the first camera part 41 and the cavity 8 remains unchanged. Optionally, the first support 71 is a support rod, one end of the support rod is connected to the side wall of the cavity 8, and the other opposite end is connected to the first camera part 41 to fix the first camera part 41 to the cavity 8.

[0051] In the wafer edge defect detection device of this embodiment, the wafer 1 is placed on the supporting table 2, and the supporting table 2 is rotated by the rotating shaft 3. The first camera unit 41 can obtain multiple wafer edge images, and the image processing unit 5 is used to splice the wafer edge images to form a wafer contour map. By comparing and detecting the wafer contour map, the efficiency and accuracy of wafer defect detection are effectively improved, and the detection cost is relatively low; the first vacuum hole 21 is connected to the vacuum passage 31 and connected to the vacuum pumping pipeline, thereby realizing the adsorption of the wafer 1, ensuring that the relative position of the wafer 1 and the supporting table 2 remains unchanged during the detection process; multiple first openings 211 are evenly arranged around the center of the supporting table 2, which can simultaneously realize the adsorption of wafers 1 of different thicknesses, thereby improving the applicability of the device and ensuring the adsorption effect of the wafer 1.

[0052] Example 2

[0053] This embodiment provides another wafer edge defect detection device, referring to Figure 9 The same points as those in Example 1 are not described in detail. The differences are as follows:

[0054] Compared to the wafer edge defect detection device of the first embodiment, the wafer edge defect detection device of this embodiment further includes a second camera unit 42. The second camera unit 42 is located below the supporting table 2. The supporting table 2 is a transparent table. The second camera unit 42 is aligned with the wafer edge on the back side of the wafer 1 to obtain an image of the wafer edge on the back side of the wafer 1. The second camera unit 42 is connected to the image processing unit 5, thereby transmitting the obtained wafer edge image on the back side of the wafer 1 to the image processing unit 5 for image processing. Optionally, the second camera unit 42 is an industrial camera. The second camera unit 42 is coaxially arranged with the first camera unit 41, so that the first camera unit 41 and the second camera unit 42 can simultaneously obtain an image of the front side and an image of the back side of the wafer edge, so as to facilitate subsequent processing and comparison of the wafer contour image on the front side of the wafer 1 and the wafer contour image on the back side of the wafer 1.

[0055] In this embodiment, the supporting table 2 is made of a transparent material, such as quartz, polyetheretherketone, etc. The supporting table 2 has a plate-like structure as a whole, and the upper and lower surfaces of the supporting table 2 are both smooth planes, so that the second camera unit 42 can obtain a clear image of the back of the wafer 1 through the supporting table 2.

[0056] In this embodiment, the support part 7 of the wafer edge defect detection device also includes a second support 72, and the two ends of the second support 72 are respectively connected to the bottom surface of the working chamber 81 and the second camera part 42, so that the second support 72 can support the second camera part 42. Optionally, the second support 72 is a support rod, and the opposite ends of the support rod are respectively fixedly connected to the second camera part 42 and the bottom surface of the working chamber 81, so that the second camera part 42 is fixedly connected to the cavity 8.

[0057] In some specific embodiments, when used, for example, the first angle can be set to 30°. Every time the supporting table 2 rotates 30°, the first camera unit 41 and the second camera unit 42 each obtain a wafer edge image, and a total of 24 wafer edge images are obtained, of which 12 are wafer edge images of the front side of the wafer 1, and the other 12 are wafer edge images of the back side of the wafer 1. The image processing unit 5 is used to splice the wafer edge image of the front side of the wafer 1 and the wafer edge image of the back side of the wafer 1 respectively to generate a wafer contour map of the front side of the wafer 1 and a wafer contour map of the back side of the wafer 1 respectively. The wafer contour map of the front side of the wafer 1 and the wafer contour map of the back side of the wafer 1 are respectively compared with the wafer template map to obtain the position of the chipping defects on the front and back sides of the wafer, mark the position of the chipping defects, and save the marked wafer contour map, thereby effectively improving the detection effect of wafer defects.

[0058] The wafer edge defect detection device of this embodiment also includes the supporting table 2, rotating axis 3, first camera unit 41 and image processing unit 5 in the first embodiment, and therefore also has the beneficial effects of the first embodiment; and by utilizing the first camera unit 41 and the second camera unit 42, the wafer contour images of the front side and the back side of the wafer can be obtained at the same time. By simultaneously detecting the wafer contour images of the front side and the back side of the wafer, the detection efficiency and detection accuracy are further improved, and the detection effect of wafer defects is improved.

[0059] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify, alter, or combine the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or variations accomplished by a person of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A wafer edge defect detection device, used for wafer edge defect detection, characterized in that: include: A carrying table having an upper surface and a lower surface opposite to each other, a wafer is placed on the upper surface of the carrying table, the wafer having a front surface and a back surface opposite to each other, the back surface being in contact with the carrying table; A first camera unit is located above the carrying table, and the first camera unit is aligned with the edge of the wafer to obtain a wafer edge image of the front side of the wafer; A rotating shaft connected to the lower surface of the carrying table to drive the carrying table to rotate around the axis of the rotating shaft; The image processing unit is connected to the first camera unit to receive the wafer edge image and process the wafer edge image to generate a wafer contour image.

2. The wafer edge defect detection device according to claim 1, characterized in that: The wafer, the carrying table and the rotating axis are coaxially arranged.

3. The wafer edge defect detection device according to claim 1, wherein: The rotating shaft has a vacuum passage connected to the vacuum pumping pipeline, and the supporting table is provided with a plurality of first vacuum holes spaced apart from each other. The first vacuum holes are connected to the vacuum passage and have a first opening on the upper surface of the supporting table. The vacuum pumping pipeline passes through the first opening to enable the supporting table to adsorb the wafer.

4. The wafer edge defect detection device according to claim 3, characterized in that: In a top view of the supporting platform along its axial direction, the plurality of first openings are evenly distributed around the center of the supporting platform.

5. The wafer edge defect detection device according to claim 3, wherein: A first groove is formed on the lower surface of the supporting table. The first groove is connected to the vacuum passage. The first vacuum hole is connected to the first groove, so that the first vacuum hole is connected to the vacuum passage.

6. The wafer edge defect detection device according to claim 5, characterized in that: The vacuum passage, the first groove and the rotating shaft are coaxially arranged, and the surface of the rotating shaft close to the carrying table completely covers the first groove.

7. The wafer edge defect detection device according to claim 1, wherein: It also includes a second camera unit, which is located below the supporting table. The supporting table is a transparent table. The second camera unit is aligned with the edge of the wafer to obtain the wafer edge image on the back of the wafer.

8. The wafer edge defect detection device according to claim 7, characterized in that: It also includes a cavity, in which a working chamber is formed, and the first camera part, the second camera part and the supporting platform are all located in the working chamber.

9. The wafer edge defect detection device according to claim 8, characterized in that: It also includes a supporting portion, which includes a first support and a second support, wherein opposite ends of the first support are respectively connected to the side wall of the working chamber and the first camera portion to support the first camera portion, and opposite ends of the second support are respectively connected to the bottom surface of the working chamber and the second camera portion to support the second camera portion.

10. The wafer edge defect detection device according to claim 7, wherein: The system further includes a driving portion, which is located outside the working chamber. One end of the rotating shaft away from the carrying table is connected to the driving portion, so that the driving portion drives the rotating shaft to rotate.

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