Wafer processing method and thinning machine

Abstract

The application discloses a wafer processing method and a thinning machine. The wafer processing method comprises the following steps: extracting a contour graph reflecting the edge contour shape of a grinding wheel from acquired image information of the grinding wheel; calculating the diameter of the grinding wheel through the contour graph; and driving the grinding wheel to move to a grinding position along a predetermined direction by using a driving mechanism to drive a main shaft of the thinning machine after determining the grinding position of the grinding wheel on the wafer based on the diameter, so as to grind and thin the wafer. The application solves the problem that the Taiko ring width is different due to the different sizes of different types of grinding wheels installed on the main shaft, and the requirement of the Taiko ring width cannot be met.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and more specifically, to a wafer processing method and a thinning machine. Background Technology

[0002] With technological advancements, the demand for ultra-thin wafers has been increasing in recent years, leading to the emergence of a new wafer back-side grinding technology—the Taiko thinning process. The Taiko thinning process is a wafer back-side masking technology that preserves a certain width (approximately 3mm) of the wafer's outer edge during grinding (this edge is commonly referred to as the Taiko ring), thinning only the center of the wafer to reduce warpage. This significantly reduces the transfer requirements of subsequent processing equipment and the risk of breakage, meeting the processing needs of ultra-thin wafers with a thickness of less than 100µm. Currently, the spindle of thinning machines cannot move laterally, only vertically. Because different types of grinding wheels have different sizes, the width of the thinned Taiko ring varies, failing to meet the required width of the wafer Taiko ring.

[0003] Currently, the spindle of the thinning machine using the Taiko thinning process cannot move horizontally, but can only move vertically. Because different types of grinding wheels installed on the spindle have different sizes, the width of the thinned Taiko ring will also be different, which cannot meet the Taiko ring width requirements. Summary of the Invention

[0004] The main objective of this application is to provide a wafer processing method and a thinning machine to solve the problem mentioned in the background art that the width of the thinned Taiko ring is different due to the different sizes of the grinding wheels mounted on the spindle, which makes it impossible to meet the Taiko ring width requirements.

[0005] According to one aspect of this application, a wafer fabrication method is provided, comprising:

[0006] Step S1: Extract the contour graphic that represents the edge contour shape of the grinding wheel from the acquired image information of the grinding wheel;

[0007] Step S2: Calculate the diameter of the grinding wheel using the outline diagram;

[0008] Step S3: After determining the grinding position of the grinding wheel on the wafer based on the diameter, the main shaft on the thinning machine is driven by the drive mechanism to move the grinding wheel along the predetermined direction to the grinding position to grind and thin the wafer.

[0009] Furthermore, the image information includes multiple images, and step S1 includes:

[0010] Step S11: During the process of the spindle driving the grinding wheel to rotate, multiple images are acquired by the image acquisition device, and any one of the images is the image acquired when any contour area of ​​the grinding wheel enters the image acquisition range of the image acquisition device;

[0011] Step S12: Extract contour segments from the image, whereby the contour segments are graphic line segments that represent the shape of the edge contour of the contour region;

[0012] Step S13: Combine multiple contour segments corresponding to multiple images to form the contour graphic.

[0013] Further, step S12 includes:

[0014] Step S121: Extract multiple sampling points from the image, wherein the sampling points are located at the edge of the contour region;

[0015] Step S122: Determine the spatial coordinate values ​​of the multiple sampling points respectively, so as to draw the contour segment according to the spatial coordinate values.

[0016] Further, step S2 includes:

[0017] Obtain the spatial coordinate values ​​of any two sampling points in the contour graphic, and calculate the distance between any two sampling points based on the spatial coordinate values, so that the distance value with the largest value is used as the diameter value.

[0018] Further, the grinding wheel includes a first grinding wheel and a second grinding wheel, wherein the first grinding wheel is the grinding wheel used before the spindle is replaced and the second grinding wheel is used, and the step S3, which determines the grinding position of the grinding wheel on the wafer based on the diameter, includes:

[0019] Step S31: Obtain the first diameter of the first grinding wheel and the second diameter of the second grinding wheel, wherein the first diameter and the second diameter are calculated by the method described in steps S1 to S2;

[0020] Step S32: Determine the compensation amount for the spindle to move along the predetermined direction based on the first diameter and the second diameter, so as to determine the grinding position of the second grinding wheel based on the compensation amount, wherein the absolute value of the difference between the first diameter and the second diameter is a first difference value, and the compensation amount is half of the first difference value.

[0021] According to another aspect of this application, a thinning machine is provided, comprising:

[0022] Mounting base;

[0023] A spindle is mounted on the mounting base and a grinding wheel is mounted on the spindle.

[0024] A drive mechanism is provided on the mounting base and connected to the spindle. The drive mechanism is used to drive the spindle to move the grinding wheel in a predetermined direction.

[0025] A detection component, the detection component being used to perform the wafer processing method.

[0026] Furthermore, the detection component includes:

[0027] The controller is electrically connected to the drive mechanism;

[0028] An image acquisition device is disposed on the mounting base near the spindle and electrically connected to the controller.

[0029] Furthermore, the drive mechanism includes:

[0030] An electric motor, which is mounted on the mounting base, includes a rotating shaft;

[0031] A lead screw, which is mounted on the mounting base and extends along the predetermined direction, is connected to the rotating shaft via a transmission connector to rotate about its own axis under the drive of the motor.

[0032] A screw connector is provided, through which the main shaft is screwed to the lead screw to reciprocate along the predetermined direction under the drive of the lead screw.

[0033] Furthermore, the drive mechanism also includes:

[0034] A sliding connection assembly, comprising at least two sets, wherein the at least two sets of the sliding connection assemblies are disposed on the mounting base and respectively located on opposite sides of the lead screw along its own radial direction, the sliding connection assembly being connected to the spindle, and the sliding connection assembly being used to enhance the stability of the spindle during movement.

[0035] Furthermore, the sliding connection component includes:

[0036] A guide rail is mounted on the mounting base, and the length of the guide rail extends along the predetermined direction and is parallel to the lead screw;

[0037] A slider is connected to the guide rail and can slide relative to the guide rail in the predetermined direction. The main shaft is connected to the slider on the side near the lead screw.

[0038] This application extracts the contour of the grinding wheel by acquiring its image information, and then uses this contour to determine the diameter of the grinding wheel currently installed on the spindle of the thinning machine. Based on the grinding wheel diameter, the grinding position of the grinding wheel on the wafer is determined. A drive mechanism then drives the spindle to move the grinding wheel to this grinding position to perform grinding and thinning of the wafer. This achieves the goal of automatically adjusting the grinding position for different sized grinding wheels during wafer thinning. Therefore, even when using grinding wheels of different sizes to thin the wafer, the width of the Taiko ring processed on the wafer can meet the processing requirements, improving the wafer thinning accuracy. Attached Figure Description

[0039] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0040] Figure 1 This is a schematic flowchart of a wafer fabrication method provided in an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of the process for obtaining a contour graphic according to an embodiment of the present invention;

[0042] Figure 3 for Figure 2 A schematic diagram illustrating the process of extracting contour segments from an image;

[0043] Figure 4 This is a schematic diagram of the process for determining the grinding position in one embodiment of the present invention;

[0044] Figure 5 A schematic diagram illustrating the principle of an image acquisition device for capturing images of a rotating grinding wheel;

[0045] Figure 6 This is a schematic diagram illustrating the principle of calculating the compensation amount;

[0046] Figure 7 This is a schematic diagram of the structure of a thinning machine provided in an embodiment of the present invention;

[0047] Figure 8 for Figure 7 A schematic diagram of the assembly structure of the drive mechanism.

[0048] The above figures include the following reference numerals:

[0049] 10. Mounting base; 20. Spindle; 21. Grinding wheel; 30. Drive mechanism; 31. Motor; 32. Lead screw; 33. Threaded connector; 34. Guide rail; 35. Slider; 36. Bearing housing; 37. Coupling. Detailed Implementation

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0053] Currently, the spindle 20 of the wafer thinning machine can only move up and down. When different types and sizes of grinding wheels 21 are installed on the spindle 20, the width of the Taiko rings thinned using different sized grinding wheels 21 will vary, resulting in some grinding wheels 21 producing Taiko rings with varying widths, failing to meet the width requirements of wafer Taiko rings. To address this problem, the first embodiment of this invention provides a wafer processing method based on a detection component of a wafer thinning machine. This thinning machine also includes a mounting base 10, a spindle 20, and a drive mechanism 30 detection component. The spindle 20 is mounted on the mounting base 10, and the grinding wheel 21 is mounted on the spindle 20. The drive mechanism 30 is mounted on the mounting base 10 and connected to the spindle 20, and is used to drive the spindle 20 to move the grinding wheel 21 in a predetermined direction. Please refer to [link to relevant documentation]. Figure 1 The specific steps involved in the wafer fabrication process for the testing components are as follows:

[0054] Step S1: Extract the contour graphic that represents the edge contour shape of the grinding wheel 21 from the acquired image information of the grinding wheel 21.

[0055] Step S2: Calculate the diameter of the grinding wheel 21 using the contour graphic.

[0056] Step S3: After determining the grinding position of the grinding wheel 21 on the wafer based on the diameter, the main spindle 20 on the thinning machine is driven by the drive mechanism 30 to move the grinding wheel 21 along the predetermined direction to the grinding position to grind and thin the wafer.

[0057] As can be seen, in this embodiment of the invention, after obtaining the image information of the grinding wheel 21 to extract its contour pattern, the diameter of the grinding wheel 21 currently installed on the spindle 20 of the thinning machine is obtained from the contour pattern. Based on the diameter of the grinding wheel 21, the grinding position of the grinding wheel 21 on the wafer is determined, and the drive mechanism 30 drives the spindle 20 to move the grinding wheel 21 to that grinding position to perform grinding and thinning of the wafer. This achieves the purpose of automatically adjusting the grinding position of the grinding wheel 21 for different sizes of grinding wheels 21 when grinding and thinning the wafer. Therefore, after grinding and thinning the wafer using grinding wheels 21 of different sizes, the width of the Taiko ring processed on the wafer can meet the processing requirements, improving the processing and thinning accuracy of the wafer using grinding wheels 21 of different sizes.

[0058] like Figure 2 As shown, the image information includes multiple images. Step S1, which involves extracting the contour graphic representing the edge outline shape of the grinding wheel 21 from the acquired image information, includes:

[0059] Step S11: During the rotation of the grinding wheel 21 driven by the spindle 20, multiple images are acquired by the image acquisition device. Any one of these images is the image captured when any contour area of ​​the grinding wheel 21 enters the image acquisition range of the image acquisition device. The image acquisition device in this embodiment may include a camera, camcorder, scanner, other devices with photo-taking functions (mobile phones, tablets, etc.), and video capture cards, etc.

[0060] Step S12: Extract contour segments from the image. A contour segment is a graphic line segment that represents the shape of the edge of the contour region. For example, the arc segment AB of the grinding wheel 21 extracted from any image.

[0061] Step S13: Combine multiple contour segments corresponding to multiple images to form a contour graphic.

[0062] To facilitate the acquisition of image information of the grinding wheel 21 mounted on the spindle 20, and thereby extract the contour image of the grinding wheel 21 from the image information, this embodiment of the invention utilizes the characteristic that the spindle 20 can drive the grinding wheel 21 to rotate and grind around its own axis. While the spindle 20 is started to drive the grinding wheel 21 to rotate, images of the rotating grinding wheel 21 are continuously acquired by an image acquisition device. In other words, this embodiment can continuously acquire images of any contour area of ​​the grinding wheel 21 within its image acquisition range using an image acquisition device. Images of multiple consecutive contour areas constitute the image information needed to extract the contour graphic, making the image acquisition operation convenient and fast. Figure 5 As shown, when the image acquisition device is a camera, when the contour area containing the arc segment AB of the rotating grinding wheel 21 enters the camera's field of view, the camera acquires an image of the contour area containing the arc segment AB. When the contour area containing the arc segment BC of the grinding wheel 21 enters the camera's field of view, the camera acquires an image of the contour area containing the arc segment BC, and so on, until multiple images of the contour areas containing all the arc segments of the entire grinding wheel 21 are acquired. Then, the acquired multiple images are sent to a controller electrically connected to the camera. The contour extraction program set in the controller extracts and stitches each contour segment (such as arc segment AB, arc segment BC, etc.). Executing the contour extraction program stitches the multiple contour segments corresponding to multiple images to form the complete contour graphic of the grinding wheel 21.

[0063] like Figure 3 As shown, step S12, the step of extracting the contour segment from the image, may specifically include:

[0064] Step S121: Extract multiple sampling points from the image. The sampling points are located at the edges of the contour regions. For example, the contour region containing arc segment AB is the first region, and the contour region containing arc segment BC is the second region. Multiple sampling points can be extracted from the edges of the first region, such as extracting forty sampling points from a1 to a40. Then, multiple sampling points can be extracted from the edges of the second region, such as extracting forty sampling points from b1 to b40. The specific number of sampling points sampled from each image and the specific positions of each sampling point on the edges of the contour regions can be determined according to actual calculation needs. This embodiment of the invention does not impose a unique limitation here.

[0065] Step S122: Determine the spatial coordinate values ​​of multiple sampling points to draw a contour segment based on the spatial coordinate values. For example, obtain the spatial coordinate values ​​of forty sampling points, from a1 to a40. The spatial coordinate values ​​can be represented by the values ​​of the corresponding sampling points on the X-axis and Y-axis of the coordinate system. Then, draw the corresponding contour segment based on the spatial coordinate values ​​of each sampling point (e.g., draw the arc segment AB). Subsequently, multiple contour segments can be spliced ​​together to form a complete contour graphic that reflects the shape of the grinding wheel 21, i.e., a circular contour. That is, this embodiment of the invention is based on a visual edge extraction algorithm to extract multiple sampling points from the edge of the contour area in the image. The main shaft 20 drives the grinding wheel 21 to rotate slowly and continuously, identify the images continuously acquired by the image acquisition device and extract the corresponding sampling points in the images. Finally, a circular contour graphic is fitted based on the multiple contour segments determined by the obtained sampling points, and the diameter of the grinding wheel 21 is finally obtained through the contour graphic.

[0066] After obtaining the outline pattern of the grinding wheel 21, step S2 of this embodiment, which involves calculating the diameter of the grinding wheel 21 based on the outline pattern, includes: obtaining the spatial coordinate values ​​of any two sampling points in the outline pattern, and calculating the distance between any two sampling points based on the spatial coordinate values, with the largest distance value being used as the diameter value. Alternatively, based on the spatial coordinate values ​​of each sampling point constituting the outline pattern, the spatial coordinate values ​​of the center of the circular outline pattern can be determined, and the distance from the center to any sampling point can be calculated based on the spatial coordinate values ​​of the center and any sampling point to obtain the diameter of the grinding wheel 21.

[0067] Based on this embodiment, the grinding position of the grinding wheel 21 on the wafer can be determined according to the actual diameter of the grinding wheel 21. This avoids the inconvenience and waste of resources caused by having to move the grinding wheel 21 significantly laterally in a predetermined direction each time it is obtained. In this embodiment, after obtaining the diameter of the newly replaced grinding wheel 21, and knowing the grinding position of the previous grinding wheel 21 during wafer thinning, the current grinding wheel 21 can be adjusted slightly based on the grinding position of the previous wheel 21 and the diameter of the current wheel 21 to achieve precise wafer processing. Therefore, the grinding wheel 21 in this embodiment includes a first grinding wheel and a second grinding wheel. The first grinding wheel is the grinding wheel 21 used before the spindle 20 is replaced and the second grinding wheel is used. Figure 4 As shown, step S3, which involves determining the grinding position of the grinding wheel 21 on the wafer based on its diameter, includes:

[0068] Step S31: Obtain the first diameter of the first grinding wheel and the second diameter of the second grinding wheel. Both the first and second diameters are calculated using the methods in steps S1 to S2.

[0069] Step S32: Determine the compensation amount for the spindle 20 to move in a predetermined direction based on the first diameter and the second diameter, so as to determine the grinding position of the second grinding wheel based on the compensation amount, wherein the absolute value of the difference between the first diameter and the second diameter is a first difference value, and the compensation amount is half of the first difference value. Figure 6 As shown, if the diameter of the first grinding wheel is D2 and the diameter of the second grinding wheel is D1, the compensation amount = radius of the first grinding wheel - radius of the second grinding wheel = (D2 - D1) / 2. The compensation amount can then be calculated (the magnitude of this compensation amount is as follows). Figure 6 The length of the D3 indicator shown is used to automatically adjust the spindle 20 to move laterally in a predetermined direction using the drive mechanism 30 to a grinding position that can thin the wafer to meet the Taiko ring width requirement. This position can be the distance corresponding to the value of the radial movement compensation of the second grinding wheel along the wafer. After adjusting the lateral position of the second grinding wheel, the spindle 20 moves downward to bring the grinding wheel 21 closer to the wafer and grind and thin the wafer.

[0070] The second embodiment of the present invention provides a thinning machine, such as Figure 7 As shown, the thinning machine includes a mounting base 10, a spindle 20, a drive mechanism 30, and a detection assembly. The spindle 20 is mounted on the mounting base 10, and a grinding wheel 21 for grinding wafers is mounted on the spindle 20. The drive mechanism 30 is mounted on the mounting base 10 and connected to the spindle 20. The drive mechanism 30 drives the spindle 20 to drive the grinding wheel 21 along a predetermined direction (such as...). Figure 8 The movement is indicated by the arrow Z. The detection component is used to execute the wafer fabrication method provided in the first embodiment of the present invention, which is detailed in the first embodiment of the present invention.

[0071] The detection components include a controller and an image acquisition device. The controller is electrically connected to the drive mechanism 30, and the image acquisition device is positioned on the mounting base 10 near the spindle 20 and electrically connected to the controller. The image acquisition device is used to continuously acquire images of the rotating grinding wheel 21 as the spindle 20 drives it to rotate. In this embodiment, the image acquisition device can continuously acquire images of any contour area of ​​the grinding wheel 21 that enters its image acquisition range. Images of multiple consecutive contour areas constitute the image information required to extract the contour graphic, making the image acquisition operation convenient and fast. For example, when the contour area containing the arc segment AB of the rotating grinding wheel 21 enters the image acquisition range of the image acquisition device, the image acquisition device acquires an image of the contour area containing the arc segment AB. When the contour area containing the arc segment BC of the grinding wheel 21 enters the image acquisition range, the image acquisition device acquires an image of the contour area containing the arc segment BC. This process continues until multiple images of all the contour areas containing the arc segments of the entire grinding wheel 21 have been acquired. Then, the obtained multiple images are sent to the controller. The contour extraction program set in the controller is used to extract and stitch together each contour segment (such as arc segment AB, arc segment BC, etc.). Executing the contour extraction program will stitch together the multiple contour segments corresponding to multiple images to form the complete contour graphic of the grinding wheel 21.

[0072] like Figure 8 As shown, in this embodiment, after determining the grinding position of the grinding wheel 21 on the wafer, in order for the drive mechanism 30 to drive the spindle 20 to move the grinding wheel 21 laterally in a predetermined direction to the grinding position, the drive mechanism 30 in this embodiment includes a motor 31, a lead screw 32, and a screw connector 33. The screw connector 33 can be a nut seat adapted to the lead screw 32. The motor 31 is mounted on the mounting base 10 and includes a rotating shaft. The lead screw 32 is mounted on the mounting base 10, and the length of the lead screw 32 extends in a predetermined direction (i.e., the predetermined direction is the axial direction of the lead screw 32). The lead screw 32 is connected to the rotating shaft through a transmission connector to rotate around its own axis under the drive of the motor 31. The transmission connector may include a coupling 37, that is, the lead screw 32 is connected to the rotating shaft of the motor 31 through the coupling 37 to transmit the rotational kinetic energy of the rotating shaft to the lead screw 32. The spindle 20 is screwed to the lead screw 32 via the screw connector 33 so that it can reciprocate in a predetermined direction under the drive of the lead screw 32, thereby moving the grinding wheel 21 to the determined grinding position.

[0073] The drive mechanism 30 in this embodiment of the invention further includes a sliding connection assembly. The sliding connection assembly comprises at least two sets, which are disposed on the mounting base 10 and located on opposite sides of the lead screw 32 along its radial direction. The sliding connection assembly is connected to the main shaft 20 and is used to enhance the stability of the main shaft 20 during movement. Specifically, the sliding connection assembly includes a guide rail 34 and a slider 35. The guide rail 34 is mounted on the mounting base 10, and its length extends along a predetermined direction and is parallel to the lead screw 32. The slider 35 is connected to the guide rail 34 and can slide relative to the guide rail 34 along a predetermined direction. The side of the main shaft 20 closest to the lead screw 32 is connected to the slider 35. Thus, during the movement of the main shaft 20, the slider 35 moves with the main shaft 20 relative to the guide rail 34 along a predetermined direction, thereby enhancing the stability of the main shaft 20 during movement. At least two sliders 35 can be disposed on each guide rail 34, thereby further improving the structural stability of the main shaft 20 during movement.

[0074] Specifically, in this embodiment, the mounting base 10 is provided with at least two bearing seats 36. These bearing seats 36 are spaced apart along the axial direction of the motor 31's rotation shaft on the mounting base 10. A lead screw 32 is mounted on the bearing seats 36 and connected to the motor 31's rotation shaft via a coupling 37. After the motor 31 starts, as the rotation shaft drives the lead screw 32 to rotate, the spindle 20, under the rotational engagement of the nut seat and the lead screw 32, drives the slider 35 to move relative to the slide rail. This moves the grinding wheel 21 on the spindle 20 to a predetermined grinding position to grind and thin the wafer placed on the wafer thinning machine's substrate. The thinning machine in this embodiment may include two spindles 20, a worktable, and three substrates, as well as material handling components (such as a wafer loading hand, wafer unloading hand, cleaning table, positioning table, and center hand). Each spindle 20 can be configured with a corresponding drive mechanism 30 to achieve transverse linear motion of the spindle 20 along a predetermined direction.

[0075] The third embodiment of the present invention is based on the above two embodiments, and in conjunction with the appendix. Figures 1 to 8 This paper provides an application example of a wafer processing method using a tube thinning machine.

[0076] This application embodiment adds a drive mechanism 30 and an image acquisition device to the thinning machine, which can drive the spindle 20 to move laterally in a predetermined direction. The image acquisition device is used to acquire images of the grinding wheel 21 mounted on the spindle 20. Based on a visual edge extraction algorithm, this embodiment extracts multiple sampling points from the edges of the contour regions in the image. The spindle 20 drives the grinding wheel 21 to rotate slowly and continuously, recognizing and extracting the corresponding sampling points from the images continuously acquired by the image acquisition device. Finally, based on the multiple contour segments determined by the obtained sampling points, a circular contour graphic is fitted, and the diameter of the grinding wheel 21 is obtained from the contour graphic.

[0077] After collecting and identifying the diameter of the grinding wheel 21 installed on the spindle 20, the system automatically calculates and adjusts the transverse position of the spindle 20. Through the transverse movement of the spindle 20, the grinding wheel 21 is moved to the grinding position that meets the processing requirements, so that the wafers ground by installing grinding wheels 21 of different sizes can meet the width requirements of the Taiko ring.

[0078] In this application embodiment, a grinding wheel 21 is mounted on the spindle 20. The wafer is adsorbed onto the wafer support table of the thinning machine. Before grinding, the diameter of the mounted grinding wheel 21 is calculated and derived by a detection component. After determining the grinding position of the grinding wheel 21 on the wafer based on its diameter, the drive mechanism 30 adjusts the lateral movement distance of the spindle 20 in a predetermined direction. Then, the back side of the wafer is ground by high-speed rotation of the grinding wheel 21, leaving a Taiko ring of approximately 3mm width on the outer edge of the ground wafer. The wafer processing grinding method in this application embodiment can significantly reduce wafer warpage and lower the risk of damage to thin wafers during handling.

[0079] Before actively controlling the grinding wheel 21 to perform wafer grinding, the steps for automatically adjusting the transverse movement of the spindle 20 in this application embodiment are as follows:

[0080] Image acquisition is performed using a camera to capture images of the grinding wheel 21 on the spindle 20 and its edges. A visual edge extraction algorithm is then used to remove potential errors (such as extra pixels captured during rotation or pixels on objects other than the grinding wheel 21 in the image). Multiple sampling points are extracted from the edges of each contour region of the grinding wheel 21. During extraction, pixels at the beginning and end of the contour region are removed, and 40 sampling points are uniformly sampled. The spatial coordinates of each sampling point are determined, thus completing the acquisition of the corresponding contour segment (e.g., sampling of the arc segment AB). As the spindle 20 continues to rotate, images are continuously acquired and recognized using the same method, ultimately fitting a circular contour shape to obtain the diameter of the grinding wheel 21.

[0081] This application embodiment can also calculate the compensation amount required for the spindle 20 to laterally move through the currently installed grinding wheel 21 (such as the second grinding wheel) based on the diameters of the two different grinding wheels 21. For example, if the diameter of the first grinding wheel before the spindle 20 uses the second grinding wheel is D2 and the diameter of the second grinding wheel is D1, the compensation amount = radius of the first grinding wheel - radius of the second grinding wheel = (D2 - D1) / 2. Based on the calculated compensation amount, the drive mechanism 30 can automatically adjust the spindle 20 to laterally move in a predetermined direction to a grinding position that can thin the wafer to meet the Taiko ring width requirement. For example, the distance corresponding to the value of the compensation amount for the second grinding wheel moving radially along the wafer is sufficient. After adjusting the lateral position of the second grinding wheel, the spindle 20 moves downwards to bring the grinding wheel 21 closer to the wafer and grinds and thins the wafer.

[0082] For different wafer processing materials, the thinning machine spindle 20 uses different types of grinding wheels 21. Since the size of the grinding wheel 21 varies, in order to meet the 3mm width requirement of the Taiko ring, this application embodiment adds a drive mechanism 30 that can drive the spindle 20 to move laterally in a predetermined direction, so as to move the grinding wheels 21 of different sizes to the grinding position that meets the requirements of the processed Taiko ring. It can be compatible with multiple types of grinding wheels 21, and the grinding process is efficient and precise.

[0083] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0084] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0085] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A wafer fabrication method, characterized in that, include: Step S1: Extract the contour graphic that represents the edge contour shape of the grinding wheel (21) from the acquired image information of the grinding wheel (21); Step S2: Calculate the diameter of the grinding wheel (21) using the outline pattern; Step S3: After determining the grinding position of the grinding wheel (21) on the wafer based on the diameter, the main shaft (20) on the thinning machine is driven by the drive mechanism (30) to move the grinding wheel (21) along the predetermined direction to the grinding position to grind and thin the wafer.

2. The wafer fabrication method according to claim 1, characterized in that, The image information includes multiple images, and step S1 includes: Step S11: During the process of the spindle (20) driving the grinding wheel (21) to rotate, multiple images are acquired by the image acquisition device, and any one of the images is the image acquired when any contour area of ​​the grinding wheel (21) enters the image acquisition range of the image acquisition device; Step S12: Extract contour segments from the image, whereby the contour segments are graphic line segments that represent the shape of the edge contour of the contour region; Step S13: Combine multiple contour segments corresponding to multiple images to form the contour graphic.

3. The wafer fabrication method according to claim 2, characterized in that, Step S12 includes: Step S121: Extract multiple sampling points from the image, wherein the sampling points are located at the edge of the contour region; Step S122: Determine the spatial coordinate values ​​of the multiple sampling points respectively, so as to draw the contour segment according to the spatial coordinate values.

4. The wafer fabrication method according to claim 3, characterized in that, Step S2 includes: Obtain the spatial coordinate values ​​of any two sampling points in the contour graphic, and calculate the distance between any two sampling points based on the spatial coordinate values, so that the distance value with the largest value is used as the diameter value.

5. The wafer fabrication method according to any one of claims 1 to 4, characterized in that, The grinding wheel (21) includes a first grinding wheel and a second grinding wheel. The first grinding wheel is the grinding wheel (21) used before the spindle (20) is replaced and the second grinding wheel is used. In step S3, the step of determining the grinding position of the grinding wheel (21) on the wafer based on the diameter includes: Step S31: Obtain the first diameter of the first grinding wheel and the second diameter of the second grinding wheel, wherein the first diameter and the second diameter are calculated by the method described in steps S1 to S2; Step S32: Determine the compensation amount for the spindle (20) to move along the predetermined direction based on the first diameter and the second diameter, so as to determine the grinding position of the second grinding wheel based on the compensation amount, wherein the absolute value of the difference between the first diameter and the second diameter is a first difference value, and the compensation amount is half of the first difference value.

6. A thinning machine, characterized in that, include: Mounting base (10); A spindle (20) is mounted on the mounting base (10), and a grinding wheel (21) is mounted on the spindle (20); A drive mechanism (30) is disposed on the mounting base (10) and connected to the spindle (20). The drive mechanism (30) is used to drive the spindle (20) to drive the grinding wheel (21) to move in a predetermined direction. A detection component, the detection component being used to perform the wafer processing method according to any one of claims 1 to 5.

7. The thinning machine according to claim 6, characterized in that, The detection component includes: A controller, which is electrically connected to the drive mechanism (30); An image acquisition device is disposed on the mounting base (10) near the main shaft (20) and electrically connected to the controller.

8. The thinning machine according to claim 6, characterized in that, The drive mechanism (30) includes: A motor (31) is mounted on the mounting base (10), and the motor (31) includes a rotating shaft; A lead screw (32) is mounted on the mounting base (10), and the length of the lead screw (32) extends along the predetermined direction. The lead screw (32) is connected to the rotating shaft through a transmission connector to rotate around its own axis under the drive of the motor (31). A screw connector (33) is used to connect the main shaft (20) to the lead screw (32) so that the main shaft (20) can reciprocate along the predetermined direction under the drive of the lead screw (32).

9. The thinning machine according to claim 8, characterized in that, The drive mechanism (30) further includes: The sliding connection assembly includes at least two sets, which are disposed on the mounting base (10) and located on opposite sides of the lead screw (32) along its own radial direction. The sliding connection assembly is connected to the spindle (20) and is used to enhance the stability of the spindle (20) during movement.

10. The thinning machine according to claim 9, characterized in that, The sliding connection component includes: A guide rail (34) is mounted on the mounting base (10), and the length of the guide rail (34) extends along the predetermined direction and is parallel to the lead screw (32); A slider (35) is connected to the guide rail (34) and can slide relative to the guide rail (34) in the predetermined direction. The main shaft (20) is connected to the slider (35) on the side near the lead screw (32).

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