Wafer deviation detection method, system, storage medium and electronic device

Abstract

The present invention discloses a wafer shift detection method, system, storage medium, and electronic device, comprising: obtaining a MAP image of a target wafer; wherein the MAP image includes the coordinates and bin values ​​of each die of the target wafer; calculating the edge yield of any preset edge region of the MAP image based on the bin value corresponding to each die in the preset edge region, until the edge yield of each preset edge region of the MAP image is obtained; and determining whether the target wafer has shifted based on each edge yield. By calculating the yield of the wafer edge region, the present invention improves the efficiency of wafer shift detection while avoiding significant quality problems and cost losses caused by wafer shift.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit testing, and in particular to a wafer offset detection method, system, storage medium and electronic equipment. Background Art

[0002] During wafer testing, a MAP of the test results is generated based on the set coordinates. One wafer will generate a MAP that contains the coordinates and test results (Bin values) of all individual chips (die) on the wafer. The MAP is then converted and uploaded to the packaging factory. The packaging factory will retain the die chips with good test results and enter the next process based on the test results of this map, and discard the bad ones to avoid wasting packaging materials. If the wafer is offset during testing, the die adjusted according to the MAP will be wrong. For example, the die that failed the test will be treated as good products and flow into the next process, while the die that passed the test will be discarded as bad products. This will cause major quality problems or cost losses.

[0003] Currently, wafer testers use various methods to detect wafer drift during testing, such as marking specific locations on the wafer with die markers, bare die markers, or specific bin values. These markers are easily detectable in the actual wafer and on a map. However, most wafer products currently lack die markers or specific bin values. Therefore, a technical solution is urgently needed to address these issues. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a wafer offset detection method, system, storage medium and electronic device.

[0005] The technical solution of a wafer deviation detection method of the present invention is as follows:

[0006] Acquire a MAP image of a target wafer; wherein the MAP image includes: coordinates and Bin values ​​of each Die of the target wafer;

[0007] Calculate the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area, until the edge yield of each preset edge area of ​​the MAP image is obtained;

[0008] According to each edge yield, it is determined whether the target wafer is offset.

[0009] The beneficial effects of a wafer offset detection method of the present invention are as follows:

[0010] The method of the present invention calculates the yield of the edge area of ​​the wafer, thereby improving the efficiency of wafer deviation detection and avoiding major quality problems and cost losses caused by wafer deviation.

[0011] Based on the above solution, the wafer offset detection method of the present invention can be further improved as follows.

[0012] Furthermore, the step of calculating the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area includes:

[0013] Based on the preset edge yield calculation formula and the Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated; wherein the preset edge yield calculation formula is: a i is the edge yield of any preset edge area, n i N is the number of Dies with a Bin value of 1 in any preset edge area. i is the number of all Dies in any of the preset edge areas.

[0014] Furthermore, the plurality of preset edge regions include: an upper edge region, a lower edge region, a left edge region, and a right edge region.

[0015] Furthermore, the step of determining whether the target wafer is offset according to each edge yield includes:

[0016] Determine whether a difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within a preset upper and lower offset range, obtaining a first judgment result; and determine whether the edge yield of the left edge area and the edge yield of the right edge area are within a preset left and right offset range, obtaining a second judgment result;

[0017] When the first judgment result is yes and the second judgment result is yes, it is determined that the target wafer has not shifted; when the first judgment result is no and the second judgment result is yes, it is determined that the target wafer has shifted up and down; when the first judgment result is yes and the second judgment result is no, it is determined that the target wafer has shifted left and right; when the first judgment result is no and the second judgment result is no, it is determined that the target wafer has shifted up and down and left and right.

[0018] Furthermore, it also includes:

[0019] When the target wafer is shifted, a prompt message indicating that the target wafer has shifted is provided to the user.

[0020] The technical solution of a wafer deviation detection system of the present invention is as follows:

[0021] Including: acquisition module, calculation module and detection module;

[0022] The acquisition module is used to: acquire a MAP image of a target wafer; wherein the MAP image includes: coordinates and Bin values ​​of each Die of the target wafer;

[0023] The calculation module is configured to calculate the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area, until the edge yield of each preset edge area of ​​the MAP image is obtained;

[0024] The detection module is used to determine whether the target wafer is offset according to each edge yield.

[0025] The beneficial effects of the wafer deviation detection system of the present invention are as follows:

[0026] The system of the present invention calculates the yield of the edge area of ​​the wafer, thereby improving the efficiency of wafer deviation detection and avoiding major quality problems and cost losses caused by wafer deviation.

[0027] Based on the above solution, the wafer offset detection system of the present invention can be further improved as follows.

[0028] Furthermore, the calculation module is specifically used for:

[0029] Based on the preset edge yield calculation formula and the Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated; wherein the preset edge yield calculation formula is: a i is the edge yield of any preset edge area, n i N is the number of Dies with a Bin value of 1 in any preset edge area. i is the number of all Dies in any of the preset edge areas.

[0030] Furthermore, the plurality of preset edge regions include: an upper edge region, a lower edge region, a left edge region, and a right edge region.

[0031] A technical solution of a storage medium of the present invention is as follows:

[0032] The storage medium stores instructions, and when a computer reads the instructions, the computer executes the steps of a wafer offset detection method according to the present invention.

[0033] The technical solution of an electronic device of the present invention is as follows:

[0034] The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the computer is caused to execute the steps of a wafer offset detection method according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of a process of detecting wafer deviation according to an embodiment of the present invention;

[0036] Figure 2 Schematic diagram of a MAP image in a wafer shift detection method according to an embodiment of the present invention;

[0037] Figure 3 1 is a flow chart of step S3 in a wafer deviation detection method according to an embodiment of the present invention;

[0038] Figure 4 A schematic diagram of wafer shift in a wafer shift detection method according to an embodiment of the present invention;

[0039] Figure 5 The figure is a schematic structural diagram of a wafer deviation detection system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] like Figure 1 As shown, a wafer offset detection method according to an embodiment of the present invention includes the following steps:

[0041] S1. Acquire a MAP image of a target wafer.

[0042] Among them, ① the target wafer is: any wafer to be tested. ② The MAP image includes: the coordinates and Bin values ​​of each Die of the target wafer. ③ The MAP image is the MAP image generated when the target wafer is tested. There are two specific ways to generate the MAP image. One is that the probe station used for the test wafer (equipped with a high-end robotic arm used for the test machine) will automatically output the MAP image after the test; the other is to use software to parse the MAP image from the test data after the test machine tests (communicating with the probe station to obtain the coordinates and Bin information). ④ Each wafer is composed of multiple Dies (chips), and a Die (chip) is a small piece of semiconductor material. ⑤ Such as Figure 2 As shown, each die corresponds to a coordinate and a Bin value. The coordinate reflects the location of the die in the target wafer, and the Bin value indicates whether the die has passed the test. In this embodiment, a Bin value of 1 indicates that the corresponding die has passed the test, and other Bin values ​​indicate that the corresponding die has failed the test.

[0043] S2. Calculate the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area, until the edge yield of each preset edge area of ​​the MAP image is obtained.

[0044] ① Any preset edge region is any of the following: the upper edge region, the lower edge region, the left edge region, or the right edge region. ② Edge yield is the pass rate of all dies in a preset edge region after wafer testing. Specifically, the edge yield can be calculated by calculating the ratio of dies with a Bin value of 1 within the preset edge region to the total number of dies within the preset edge region.

[0045] It should be noted that ① the upper edge area includes: each Die in the first row of the upper edge of the MAP image, the two leftmost Dies and the two rightmost Dies in each row from the second row to the middle row. ② the lower edge area includes: each Die in the first row of the lower edge of the MAP image, the two leftmost Dies and the two rightmost Dies in each row from the second row to the middle row. ③ the left edge area includes: each Die in the first column of the left edge of the MAP image, the two topmost Dies and the two bottommost Dies in each column from the second column to the middle column. ④ the right edge area includes: each Die in the first column of the right edge of the MAP image, the two topmost Dies and the two bottommost Dies in each column from the second column to the middle column.

[0046] S3. Determine whether the target wafer is offset according to each edge yield.

[0047] Specifically, whether the target wafer is shifted is determined based on the difference between the edge yields of different preset edge areas.

[0048] Preferably, the step of calculating the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area includes:

[0049] Based on a preset edge yield calculation formula and a Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated.

[0050] Among them, the preset edge yield calculation formula is: a i is the edge yield of any preset edge area, n i N is the number of Dies with a Bin value of 1 in any preset edge area. iis the number of all Dies within any of the preset edge regions. Specifically, i can be 1, 2, 3, or 4. When i is 1, any of the preset edge regions is the upper edge region; when i is 2, any of the preset edge regions is the lower edge region; when i is 3, any of the preset edge regions is the left edge region; and when i is 4, any of the preset edge regions is the right edge region.

[0051] Preferably, if Figure 3 As shown, the S3 includes:

[0052] S31. Determine whether the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within the preset range of upper and lower offsets to obtain a first judgment result, and determine whether the edge yield of the left edge area and the edge yield of the right edge area are within the preset range of left and right offsets to obtain a second judgment result.

[0053] Among them, ① the preset range for vertical offset is used to determine whether the wafer has vertical offset during the wafer test. This preset range can be set according to user needs, and there is no specific value limit. ② the preset range for horizontal offset is used to determine whether the wafer has horizontal offset during the wafer test. This preset range can be set according to user needs, and there is no specific value limit.

[0054] It should be noted that if Figure 4 As shown in the figure, assuming that the target wafer is shifted downward by one row during testing, the upper edge yield will be higher and the lower edge yield will be lower. The reason for the higher upper edge yield is that the upper edge tests all complete dies, and due to the wafer fab's manufacturing process, the DIE yield at the wafer edge is often lower than that in the wafer center. Therefore, the target wafer is shifted downward by one row during testing, resulting in a higher upper edge yield. The reason for the lower edge yield is that the lower edge tests incomplete dies, which cannot pass the test. Therefore, the target wafer is shifted downward by one row during testing, resulting in a lower lower edge yield.

[0055] S32A: When the first judgment result is yes and the second judgment result is yes, determine that the target wafer is not shifted.

[0056] Specifically, when the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within the preset range of upper and lower offsets, and the edge yield of the left edge area and the edge yield of the right edge area are within the preset range of left and right offsets, it is determined that the target wafer has not undergone any offset.

[0057] S32B: When the first judgment result is no and the second judgment result is yes, determine that the target wafer is shifted up and down.

[0058] Specifically, when the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is not within the preset range of upper and lower offsets, but the edge yield of the left edge area and the edge yield of the right edge area are within the preset range of left and right offsets, it is determined that the target wafer has undergone an upper and lower offset.

[0059] S32C: When the first judgment result is yes and the second judgment result is no, determine that the target wafer is offset leftward or rightward.

[0060] Specifically, when the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within the preset range of upper and lower offsets, but the edge yield of the left edge area and the edge yield of the right edge area are not within the preset range of left and right offsets, it is determined that the target wafer has undergone left and right offsets.

[0061] S32D: When the first judgment result is no and the second judgment result is no, determine that the target wafer has an up-down offset and a left-right offset.

[0062] Specifically, when the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is not within the preset range of upper and lower offsets, and the edge yield of the left edge area and the edge yield of the right edge area are not within the preset range of left and right offsets, it is determined that the target wafer has undergone both upper and lower offsets and left and right offsets.

[0063] Preferably, it also includes:

[0064] When the target wafer is shifted, a prompt message indicating that the target wafer has shifted is provided to the user.

[0065] Specifically, when any form of deviation (left-right deviation and / or up-down deviation) of the target wafer is detected, a prompt message indicating that the target wafer has been deviated is sent to the user's terminal via wireless transmission or wired transmission.

[0066] The technical solution of this embodiment calculates the yield of the edge area of ​​the wafer, thereby improving the efficiency of wafer shift detection and avoiding major quality problems and cost losses caused by wafer shift.

[0067] like Figure 5 As shown, a wafer deviation detection system 200 according to an embodiment of the present invention includes: an acquisition module 210, a calculation module 220 and a detection module 230;

[0068] The acquisition module 210 is used to: acquire a MAP image of a target wafer; wherein the MAP image includes: coordinates and Bin values ​​of each Die of the target wafer;

[0069] The calculation module 220 is configured to calculate the edge yield of any preset edge area of ​​the MAP image based on the Bin value corresponding to each Die in the preset edge area, until the edge yield of each preset edge area of ​​the MAP image is obtained;

[0070] The detection module 230 is configured to determine whether the target wafer is offset according to each edge yield.

[0071] Preferably, the calculation module 220 is specifically configured to:

[0072] Based on the preset edge yield calculation formula and the Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated; wherein the preset edge yield calculation formula is: a i is the edge yield of any preset edge area, n i N is the number of Dies with a Bin value of 1 in any preset edge area. i is the number of all Dies in any of the preset edge areas.

[0073] Preferably, the plurality of preset edge regions include: an upper edge region, a lower edge region, a left edge region, and a right edge region.

[0074] The technical solution of this embodiment calculates the yield of the edge area of ​​the wafer, thereby improving the efficiency of wafer shift detection and avoiding major quality problems and cost losses caused by wafer shift.

[0075] The above parameters and steps for each module to implement corresponding functions in the wafer deviation detection system 200 of this embodiment can refer to the parameters and steps in the above embodiment of a wafer deviation detection method, and will not be repeated here.

[0076] A storage medium provided by an embodiment of the present invention includes: instructions stored in the storage medium, and when a computer reads the instructions, the computer executes the steps of a wafer offset detection method. For details, please refer to the parameters and steps in the embodiment of a wafer offset detection method above, which will not be repeated here.

[0077] Computer storage media such as USB flash drives, mobile hard drives, etc.

[0078] An embodiment of the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. The electronic device is characterized in that when the processor executes the computer program, the computer executes steps of a wafer offset detection method. For details, reference may be made to the various parameters and steps in the embodiment of a wafer offset detection method described above, which will not be elaborated here.

[0079] Those skilled in the art will appreciate that the present invention can be implemented as a method, a system, a storage medium, and an electronic device.

[0080] Therefore, the present invention may be embodied in the following forms: entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or in a combination of hardware and software, generally referred to herein as a "circuit," "module," or "system." Furthermore, in some embodiments, the present invention may be embodied in the form of a computer program product embodied in one or more computer-readable media, the computer-readable media containing computer-readable program code. Any combination of one or more computer-readable media may be employed. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. Although embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and are not intended to limit the present invention. Those skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A wafer offset detection method, characterized in that: include: Acquire a MAP image of a target wafer; wherein the MAP image includes: coordinates and Bin values ​​of each Die of the target wafer; Based on the Bin value corresponding to each Die in any preset edge area of ​​the MAP image, the edge yield of the preset edge area is calculated, until the edge yield of each preset edge area of ​​the MAP image is obtained; wherein all the preset edge areas of the MAP image include: an upper edge area, a lower edge area, a left edge area, and a right edge area; Determine whether a difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within a preset upper and lower offset range, obtaining a first judgment result; and determine whether the edge yield of the left edge area and the edge yield of the right edge area are within a preset left and right offset range, obtaining a second judgment result; When the first judgment result is yes and the second judgment result is yes, it is determined that the target wafer has not shifted; when the first judgment result is no and the second judgment result is yes, it is determined that the target wafer has shifted up and down; when the first judgment result is yes and the second judgment result is no, it is determined that the target wafer has shifted left and right; when the first judgment result is no and the second judgment result is no, it is determined that the target wafer has shifted up and down and left and right.

2. The wafer shift detection method according to claim 1, wherein: The step of calculating the edge yield of any preset edge area in the MAP image based on the Bin value corresponding to each Die in the preset edge area includes: Based on the preset edge yield calculation formula and the Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated; wherein the preset edge yield calculation formula is: , is the edge yield of any of the preset edge regions, is the number of Dies with a Bin value of 1 in any of the preset edge areas, is the number of all Dies in any of the preset edge areas.

3. A wafer shift detection method according to claim 1 or 2, characterized in that: Also includes: When the target wafer is shifted, a prompt message indicating that the target wafer has shifted is provided to the user.

4. A wafer shift detection system, characterized in that: include: Acquisition module, calculation module and detection module; The acquisition module is used to: acquire a MAP image of a target wafer; wherein the MAP image includes: coordinates and Bin values ​​of each Die of the target wafer; The calculation module is configured to calculate an edge yield of any preset edge region of the MAP image based on a Bin value corresponding to each Die in the preset edge region, until the edge yield of each preset edge region of the MAP image is obtained; wherein all preset edge regions of the MAP image include an upper edge region, a lower edge region, a left edge region, and a right edge region; The detection module is used to: determine whether the difference between the edge yield of the upper edge area and the edge yield of the lower edge area is within the preset range of upper and lower offsets, and obtain a first judgment result; and determine whether the edge yield of the left edge area and the edge yield of the right edge area are within the preset range of left and right offsets, and obtain a second judgment result; when the first judgment result is yes and the second judgment result is yes, it is determined that the target wafer has not shifted; when the first judgment result is no and the second judgment result is yes, it is determined that the target wafer has shifted up and down; when the first judgment result is yes and the second judgment result is no, it is determined that the target wafer has shifted left and right; when the first judgment result is no and the second judgment result is no, it is determined that the target wafer has shifted up and down and left and right.

5. The wafer shift detection system according to claim 4, wherein: The calculation module is specifically used for: Based on the preset edge yield calculation formula and the Bin value corresponding to each Die in any preset edge area, the edge yield of any preset edge area is calculated; wherein the preset edge yield calculation formula is: , is the edge yield of any of the preset edge regions, is the number of Dies with a Bin value of 1 in any of the preset edge areas, is the number of all Dies in any of the preset edge areas.

6. A storage medium, characterized in that The storage medium stores instructions, and when a computer reads the instructions, the computer is caused to execute a wafer shift detection method according to any one of claims 1 to 3.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the computer is caused to execute the wafer shift detection method according to any one of claims 1 to 3.

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