Wafer inspection method, device and application thereof

Abstract

The application discloses a wafer detection method and device and application thereof. The wafer detection method comprises the following steps: acquiring first reference data to construct a first coordinate system, acquiring the position relationship between a template wafer and a wafer to be detected, and acquiring the reference coordinates of the wafer to be detected based on the first reference data and the position relationship; calculating the number of complete wafers under the maximum scanning field of view based on the maximum scanning field of view of image acquisition and the first reference data; setting the scanning field of view and the minimum moving step of image acquisition based on the number of complete wafers; acquiring the starting position of image acquisition based on the reference coordinates of the wafer to be detected; and planning the scanning path of wafer detection in combination with the scanning field of view and the minimum moving step. The application obtains the distribution of all wafers to be detected on the wafer based on the coordinate information of the template wafer and the adjacent wafers, and then determines the scanning field of view and the minimum moving step of image acquisition based on the proportional relationship between the wafer size and the maximum size of the scanning field of view, so that the scanning path is accurately planned to improve the detection efficiency.

Description

Technical Field

[0001] This invention belongs to the field of wafer inspection technology, specifically relating to a wafer inspection method, apparatus and its application. Background Technology

[0002] Wafers are the basic substrate material for manufacturing semiconductor chips. Through processes such as photolithography, etching, doping, and thin film deposition, tiny transistors and interconnects are built on the surface of the wafer, which is then cut into individual dies. Wafer defect detection is a critical step throughout the entire manufacturing process in order to monitor process stability, identify the source of problems, evaluate wafer quality, and predict final yield.

[0003] Common inspection methods include full inspection and sampling inspection. Full inspection generates massive amounts of image data, placing enormous pressure on storage, transmission, and analysis systems in terms of time costs. Existing sampling inspection methods have fixed scanning fields and chaotic planning paths, resulting in excessively long equipment movement paths and frequent changes in movement direction, which greatly reduces inspection efficiency.

[0004] Therefore, in order to address the above-mentioned technical problems, it is necessary to provide a wafer inspection method, apparatus, and its application. Summary of the Invention

[0005] The purpose of this invention is to provide a wafer inspection method, apparatus and its application, which can obtain the distribution of all the test dies on the wafer based on the coordinate information of the template die and the adjacent dies, and then accurately plan the scanning path based on the ratio of the die size to the maximum size of the scanning field of view, thereby improving the inspection efficiency.

[0006] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0007] A wafer inspection method, comprising:

[0008] Obtain first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain.

[0009] The position coordinates of the test grain and the template grain in a first coordinate system are obtained to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data;

[0010] The reference coordinates of the die to be tested on the wafer are obtained based on the first reference data and the positional relationship.

[0011] The number of complete grains under the maximum scanning field of view, the first spacing and the second spacing of the image acquisition are calculated, and the scanning field of view and the minimum moving step size of the image acquisition are set based on the number of complete grains.

[0012] The starting position for image acquisition is obtained based on the reference coordinates of a die to be tested, and the scanning path for wafer inspection is planned by combining the scanning field of view and the minimum moving step size.

[0013] In one or more embodiments of the present invention, the wafer inspection method includes:

[0014] First reference data is obtained based on the coordinate information of the template grain and the coordinate information of its adjacent grains. The adjacent grains are located in the extension direction of the diagonal of the template grain. The coordinate information of the template grain includes at least one pair of diagonal coordinates of the template grain. The coordinate information of the adjacent grains includes at least one angular coordinate of the adjacent grains, and the angular coordinates of the adjacent grains are located next to the diagonal coordinates.

[0015] In one or more embodiments of the present invention, the position coordinates of the test grain and the template grain in a first coordinate system are obtained to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data and includes:

[0016] Based on the wafer size, wafer center coordinates, and first reference data, calculate the maximum number of grains in the four directions of the template grains, as well as the maximum number of grains in the wafer width direction and the maximum number of grains in the height direction.

[0017] Construct a first coordinate system with the width direction as the x-axis and the height direction as the y-axis;

[0018] The position coordinates of the template grain in the first coordinate system are obtained based on the maximum number of grains in the four directions of the template grain, and the grain at at least one position coordinate in the first coordinate system is taken as the grain to be tested. The positional relationship between the grain to be tested and the template grain is determined based on the position coordinates of the grain to be tested and the template grain in the first coordinate system.

[0019] In one or more embodiments of the present invention, the number of complete grains under the maximum scanning field of view is calculated based on the maximum scanning field of view of image acquisition, the first spacing, and the second spacing, and the scanning field of view and the minimum moving step size of image acquisition are set based on the number of complete grains, including:

[0020] The maximum scanning field of view includes a maximum scanning width and a maximum scanning height. When the maximum scanning width is greater than or equal to a first spacing and the maximum scanning height is greater than or equal to a second spacing grain, the width of the scanning field of view is set based on the ratio of the maximum scanning width to the first spacing, and the height of the scanning field of view is set based on the ratio of the maximum scanning height to the second spacing; and / or,

[0021] When the maximum scan width is less than the first spacing and / or the maximum scan height is less than the second spacing, the width and / or height of the scanning field of view are set based on the ratio of the maximum scan width to the first spacing, the ratio of the maximum scan height to the second spacing, the ratio of the first spacing to the maximum scan width, and / or the ratio of the second spacing to the maximum scan height.

[0022] In one or more embodiments of the present invention, the wafer inspection method includes:

[0023] Based on maximum scan width Maximum scan height First spacing Second spacing Construct a parameter set, the parameter set including: a first parameter Second parameter Third parameter The fourth parameter ;

[0024] The number of grains that can be captured by the maximum scanning field of view is determined based on the first parameter and the second parameter;

[0025] When the maximum scanning field of view can acquire an image of at least one complete grain, the width of the scanning field of view is set to the third parameter and the first spacing. The product of the second and third parameters sets the height of the scanning field of view to the fourth parameter and the second spacing. The product;

[0026] When the maximum scanning field of view cannot capture a complete grain, the width and height of the scanning field of view are set based on the first parameter, the second parameter, the third parameter and / or the fourth parameter.

[0027] In one or more embodiments of the present invention, when FovX=1 and FovY=1, the width of the scanning field of view is... Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is ; and / or,

[0028] When FovX=1 and FovY>1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: Set the minimum step size of the scanning field of view in the height direction as follows: ; and / or,

[0029] When FovX > 1 and FovY = 1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is ; and / or,

[0030] When FovX>1 and FovY>1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is .

[0031] In one or more embodiments of the present invention, when FovX>1, the width of the scanning field of view will be... Set as The sum of the horizontally overlapping areas; and / or,

[0032] When FovY > 1, the height of the scanned field of view will be... Set as The sum of the areas overlapping vertically.

[0033] In one or more embodiments of the present invention, when FovX=1 and FovY=1, if the distance between two adjacent test grains in the width direction is less than or equal to the minimum moving step size of the scanning field in the width direction, and / or the distance between two adjacent test grains in the height direction is less than or equal to the minimum moving step size of the scanning field in the height direction, then complete images of at least two test grains are acquired simultaneously in one scanning field.

[0034] In one or more embodiments of the present invention, the starting position of image acquisition is obtained based on the reference coordinates of a grain under test, and the scanning path is planned in combination with the scanning field of view and the minimum movement step size, including:

[0035] The scanning path includes scanning rows and scanning columns, and controls the scanning field of view to move along the height direction to scan at least a portion of the image of all the grains to be tested within the current scanning column;

[0036] Control the scanning field of view to move along the width direction to switch the scanning column of the scanning field of view, and then control the scanning field of view to move along the height direction, and scan all the grains to be tested column by column.

[0037] In one or more embodiments of the present invention, the wafer inspection method further includes:

[0038] Obtain the position coordinates of all dies on the wafer, including the number of dies along the wafer width direction. The number of grains in the height direction;

[0039] Obtain the reference coordinates of two dies located at the edge of the wafer in the width direction, and calculate the x-coordinate difference between the reference coordinates of these two wafer edge dies. Use the ratio between the x-coordinate difference and the number of dies in the width direction of the wafer as the corrected first spacing.

[0040] Obtain the reference coordinates of two dies located at the edge of the wafer in the height direction, and calculate the y-coordinate difference between the reference coordinates of the two wafer edge dies. Use the ratio between the y-coordinate difference and the number of dies in the height direction of the wafer as the corrected second spacing.

[0041] Another specific embodiment of the present invention provides a wafer inspection device, the device comprising:

[0042] The data acquisition module is used to acquire first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain.

[0043] A coordinate construction module is used to obtain the position coordinates of the test grain and the template grain in a first coordinate system to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data;

[0044] The data processing module is used to obtain the reference coordinates of the die to be tested on the wafer based on the first reference data and the positional relationship;

[0045] The configuration module is used to calculate the number of complete grains under the maximum scanning field of view based on the maximum scanning field of view, the first spacing and the second spacing of the image acquisition, and to set the scanning field of view and the minimum moving step size of the image acquisition based on the number of complete grains.

[0046] The path planning module is used to obtain the starting position of image acquisition based on the reference coordinates of a die to be tested, and to plan the scanning path in combination with the scanning field of view and the minimum movement step size.

[0047] A specific embodiment of the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the wafer inspection method.

[0048] A specific embodiment of the present invention provides a computer-readable medium carrying computer-executable instructions, which, when executed by a processor, are used to implement the wafer inspection method.

[0049] Compared with the prior art, the wafer inspection method, apparatus and application of the present invention construct a first coordinate system based on the coordinate information of the template grain and adjacent grains to characterize the position coordinates of all grains to be tested on the wafer, thereby obtaining the reference coordinates of the grains to be tested, providing a route planning basis for subsequent path planning, and ensuring the accuracy of the scanning position.

[0050] Based on the proportional relationship between the first spacing, the second spacing and the maximum scanning field of view, the number of complete grain images that can be acquired is determined, and then the scanning field of view and minimum moving step size for image acquisition are determined.

[0051] Based on the scanning field of view and minimum movement step size of image acquisition, the scanning path is precisely planned to improve detection efficiency. At the same time, this invention can detect the die to be tested at any position on the wafer, and can also detect the die to be tested of any size, which greatly improves the compatibility of image acquisition equipment. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a flowchart of a wafer inspection method in one embodiment of the present invention;

[0054] Figure 2 This is a schematic diagram of the grain distribution of a wafer in one embodiment of the present invention;

[0055] Figure 3 This is a schematic diagram of the template grains and adjacent grains in one embodiment of the present invention;

[0056] Figure 4 This is a schematic diagram of the scanning field of view and path of a wafer inspection method according to an embodiment of the present invention;

[0057] Figure 5 This is a schematic diagram of the scanning field of view and path of the wafer inspection method in another embodiment of the present invention;

[0058] Figure 6 This is a schematic diagram of the scanning field of view and path of the wafer inspection method in another embodiment of the present invention;

[0059] Figure 7 This is a schematic diagram of the scanning field of view and path of the wafer inspection method in another embodiment of the present invention;

[0060] Figure 8 This is a structural diagram of a wafer inspection device according to an embodiment of the present invention;

[0061] Figure 9 This is a structural diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0062] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0063] As mentioned in the background section, semiconductor integrated circuits are the cornerstone of the modern electronics industry, widely used in almost all fields such as computers, communications, consumer electronics, automobiles, and industrial control. Wafers are the basic substrate material for manufacturing semiconductor chips, typically made of high-purity single-crystal silicon. Through hundreds of complex processes such as photolithography, etching, doping, and thin-film deposition, hundreds of millions of tiny transistors and interconnects are built layer by layer on their surface, ultimately dicing them into individual chips.

[0064] The yield of wafer manufacturing, which is the proportion of qualified chips out of the total number of chips, is one of the most critical factors determining the cost and efficiency of semiconductor production. Various surface defects are inevitably introduced during the wafer manufacturing process. To monitor process stability, identify the source of problems, assess wafer quality, and predict final yield, wafer defect detection is a crucial step throughout the entire manufacturing process.

[0065] Automated optical inspection is currently the most widely used surface defect detection technology. It utilizes high-resolution optical imaging systems (such as bright-field, dark-field, and laser scattering) to rapidly scan the wafer surface, capture images, and compare them with reference images (such as comparisons with adjacent chips or with design rules) to automatically identify and locate anomalies. The core objective of defect detection is to discover as many true defects as possible within acceptable time and equipment resources, while minimizing false positives and false negatives.

[0066] The limitations of full inspection include: excessively high time costs. With the increase in wafer size (e.g., the mainstream 300mm wafer size) and the surge in chip density (advanced processes), high-resolution, blind-spot-free automated optical inspection (AOI) of the entire wafer is extremely time-consuming, severely restricting production cycle time. In addition, full inspection has a heavy data processing burden; the massive amount of image data generated by full inspection puts enormous pressure on storage, transmission, and analysis systems.

[0067] To balance inspection efficiency, cost, and risk control, sampling inspection strategies are widely used in actual production. This involves performing detailed inspections only on a pre-selected subset of locations (points or small areas) on the wafer. By analyzing defect information from these limited sampling points, the defect distribution characteristics and overall quality status of the entire wafer can be effectively inferred, providing timely warnings of process drift or equipment malfunctions.

[0068] The effectiveness of sampling inspection is highly dependent on the selection of sampling points and the planning of the inspection path. Existing scanning fields of view are mostly fixed rectangles, which cannot be adapted to arbitrarily distributed sampling points. Engineers need to manually mark the inspection order of the sampled grains, which is time-consuming and prone to errors. The planned path may be chaotic, and there may be invalid areas in the acquisition route, resulting in excessively long equipment movement paths, frequent changes in movement direction, low acquisition efficiency, and a large number of images that need to be processed.

[0069] Based on an in-depth analysis of the aforementioned technical problems, this invention provides a wafer inspection method applicable to wafer defect inspection equipment (such as automated optical inspection (AOI) equipment and electron beam inspection equipment). It obtains the positional relationship between the die to be inspected and the template die by constructing a first coordinate system, thereby acquiring the absolute coordinate information of each die to be inspected, ensuring the accuracy of the scanning position. Based on the number of complete dies that can be acquired under the maximum scanning field of view, the scanning field of view and the minimum movement step size are set to acquire images of any die to be inspected. Specifically, it includes:

[0070] Obtain first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain.

[0071] The position coordinates of the test grain and the template grain in the first coordinate system are obtained to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data;

[0072] The reference coordinates of the die to be tested on the wafer are obtained based on the first reference data and the positional relationship;

[0073] The number of complete grains under the maximum scanning field of view, the first spacing and the second spacing of the image acquisition are calculated, and the scanning field of view and the minimum moving step size of the image acquisition are set based on the number of complete grains.

[0074] The starting position for image acquisition is obtained based on the reference coordinates of a die to be tested, and the scanning path for wafer inspection is planned by combining the scanning field of view and the minimum moving step size.

[0075] This invention constructs a first coordinate system based on the coordinate information of the template grain and its adjacent grains. Based on the position coordinates of the grain to be tested and the template grain in the first coordinate system, the reference coordinates of the grain to be tested are calculated, providing a route planning basis for subsequent path planning and ensuring the accuracy of the scanning position.

[0076] Based on the proportional relationship between the first spacing, the second spacing and the maximum scanning field of view, the number of complete grain images that can be acquired is determined, and then the scanning field of view and minimum moving step size for image acquisition are determined.

[0077] Based on the scanning field of view and minimum movement step size of image acquisition, the scanning path is precisely planned to improve detection efficiency. At the same time, this invention can detect the test die at any position on the wafer, and can also detect the test die of any size, thus improving the compatibility of image acquisition equipment.

[0078] The present invention will be further described below with reference to specific embodiments.

[0079] Example 1:

[0080] like Figure 1 As shown, the wafer inspection method of this embodiment includes:

[0081] S101, Obtain first reference data. The first reference data includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain.

[0082] Step S101 in this embodiment specifically includes:

[0083] First reference data is obtained based on the coordinate information of the template grain and the coordinate information of its adjacent grains. The adjacent grains are located in the extension direction of the diagonal of the template grain. The coordinate information of the template grain includes at least one pair of diagonal coordinates of the template grain. The coordinate information of the adjacent grains includes at least one angular coordinate of the adjacent grains, and the angular coordinates of the adjacent grains are located next to the diagonal coordinates.

[0084] like Figure 2 As shown, for example, a die at any location on the wafer is selected as the template die, and the template die is defined as... The coordinates of the upper left corner of the template grain were determined through image acquisition. lower right corner coordinates And the coordinates of the upper left corner of the adjacent grain. .

[0085] It should be noted that the coordinates of the top left and bottom right corners of the template grain and the top left corner of the adjacent grain are all absolute coordinates, that is, the coordinates of the top left and bottom right corners of the template grain and the top left corner of the adjacent grain in the mechanical coordinate system of the wafer defect inspection machine.

[0086] From this, the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain can be calculated, which is the first spacing. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain. Then, the reference coordinates of the template grains are calculated.

[0087] In this embodiment, the reference coordinates of the template grain are the center coordinates of the template grain. Then the x-axis coordinate value of the center coordinate of the template grain The y-axis coordinate of the center of the template grain Furthermore, in subsequent steps, the reference coordinates of the grain to be tested are the center coordinates of the grain. It should be noted that both the reference coordinates of the template grain and the reference coordinates of the grain to be tested are coordinates in the mechanical coordinate system.

[0088] In other alternative embodiments, the reference coordinates of the template grain can be set to other coordinates adjacent to the center coordinates of the template grain, or directly set to the coordinates of a corner of the template grain (e.g., the upper left corner coordinates or the lower right corner coordinates), and the selection of the reference coordinates of the grain to be tested adaptively follows the change of the reference coordinates of the template grain.

[0089] S102, obtain the position coordinates of the test grain and the template grain in the first coordinate system to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data;

[0090] In this embodiment, step S102 specifically includes:

[0091] Based on the wafer size, wafer center coordinates, and first reference data, calculate the maximum number of grains in the four directions of the template grains, as well as the maximum number of grains in the wafer width direction and the maximum number of grains in the height direction.

[0092] Taking the reference coordinates as the center coordinates as an example:

[0093] Calculate the maximum number of grains located to the left of the template grain. Then, round down to the nearest integer to calculate the maximum number of grains located to the right of the template grain. Round down to the nearest integer, where... For wafer size, This is the first spacing. The x-axis coordinates are the center coordinates of the template grain. The x-axis coordinate of the wafer center is given. Adding the values ​​on both sides yields the maximum number of grains along the wafer width. .

[0094] Calculate the maximum number of grains located below the template grains. Then, round down to the nearest integer to calculate the maximum number of grains located above the template grains. And round down, where This is the second spacing. The y-axis coordinates are the center coordinates of the template grains. The y-coordinate value of the wafer center is given. Adding the values ​​on both sides yields the maximum number of grains along the wafer height direction. Understandably, the wafer center coordinates These are coordinates in a mechanical coordinate system, suitable for calibrating fixed parameters to characterize the physical location of the wafer center. In this embodiment, the wafer size refers to the wafer radius; taking a 300mm wafer as an example... The value is 150.

[0095] A first coordinate system is constructed with the width direction as the x-axis and the height direction as the y-axis. In this embodiment, the center of the wafer is taken as the origin of the first coordinate system.

[0096] The position coordinates of the template grain in the first coordinate system are obtained based on the maximum number of grains in the four directions of the template grain, and the grain at at least one position coordinate in the first coordinate system is taken as the grain to be tested. The positional relationship between the grain to be tested and the template grain is determined based on the position coordinates of the grain to be tested and the template grain in the first coordinate system.

[0097] For example, if the maximum number of grains in the wafer width direction is calculated to be 14, and the maximum number of grains in the wafer height direction is also 14, then the grain layout parameters on the wafer are... Figure 3 As shown. In this embodiment, the wafer center is defined as... The position of the template grain on the wafer can be obtained based on the maximum number of grains in the four directions of the template grain. Figure 3 The coordinates of the template grains shown are: .

[0098] It is understood that in this embodiment, the area covered by the wafer is divided into several grids through the above calculation. The grids are arranged in a row and column structure. The width of each grid is the first spacing and the height is the second spacing. Each grid is used to represent a grain on the wafer (each grid actually covers a grain itself and the spacing between it and its adjacent grains). That is, the number of grids is the number of grains on the wafer.

[0099] By constructing a first coordinate system to match the position coordinates of each die on the wafer, and characterizing the positional relationship between dies based on these coordinates, the position coordinates on the same wafer remain fixed in the first coordinate system regardless of how the defect inspection equipment moves. Therefore, the position coordinates are used to quickly locate the approximate position of the die on the wafer. For example, position coordinates. The grains on the template grains are located on the template grains. The relative positions of the two remain unchanged, located to the lower left. Furthermore, their positions can be determined using coordinates. and It can obtain the number of grains that are separated by the width and height directions of two grains.

[0100] Furthermore, during the sampling inspection process, it is necessary to clearly define the sampling points. At least one grain at a specific coordinate in the first coordinate system is designated as the grain to be tested. The coordinates of the grain to be tested can provide a reference for image scanning path planning. For example, when sampling and inspecting grains located at the edge of a wafer, the coordinates of the first coordinate system... , The grain at a given location is defined as the grain to be tested.

[0101] S103, obtain the reference coordinates of the die to be tested on the wafer based on the first reference data and positional relationship;

[0102] Step S103 in this embodiment specifically includes:

[0103] Based on the difference in x-coordinates between the position coordinates of the grain under test and the template grain, the first spacing, and the reference coordinates of the template grain, the x-coordinate of the reference coordinates of the grain under test is obtained.

[0104] Based on the difference in y-coordinate between the position coordinates of the test grain and the template grain, the second spacing, and the reference coordinates of the template grain, the x-coordinate of the reference coordinates of the test grain is obtained.

[0105] For example, using the center coordinates of the template die as the reference coordinates of the template die, that is, obtaining the center coordinates of the die to be tested on the wafer based on the first reference data and positional relationship includes:

[0106] The center coordinates of the template grain are The position coordinates of the template grain are The coordinates of the position of the grain to be tested are The center coordinates of the grain to be tested are: ;

[0107] in, , .

[0108] It is understandable that acquiring the reference coordinates (i.e., coordinates in the mechanical coordinate system) of all the test dies on the wafer through image acquisition would result in a large image processing burden. In this embodiment, it is only necessary to acquire the reference coordinates of the template die. The first coordinate system constructed in step S102 can obtain the positional relationship between the test die and the template die. Based on the reference coordinates of the template die, the reference coordinates of the test die can be calculated, which reduces the difficulty of data processing.

[0109] S104 calculates the number of complete grains within the maximum scanning field of view based on the maximum scanning field of view, the first spacing, and the second spacing, and sets the scanning field of view and minimum movement step size for image acquisition based on the number of complete grains. Specifically, this includes:

[0110] The maximum scanning field of view includes the maximum scanning width and the maximum scanning height. When the maximum scanning width is greater than or equal to the first spacing and the maximum scanning height is greater than or equal to the second spacing, the width of the scanning field of view is set based on the ratio of the maximum scanning width to the first spacing, and the height of the scanning field of view is set based on the ratio of the maximum scanning height to the second spacing.

[0111] When the maximum scan width is less than the first spacing, or the maximum scan height is less than the second spacing, the width or height of the scanning field of view is set based on the ratio of the maximum scan width to the first spacing, the ratio of the maximum scan height to the second spacing, the ratio of the first spacing to the maximum scan width, or the ratio of the second spacing to the maximum scan height.

[0112] Specifically, based on the maximum scan width Maximum scan height First spacing Second spacing Construct a parameter set, which includes:

[0113] First parameter ;

[0114] Second parameter ;

[0115] Third parameter ;

[0116] Fourth parameter ,in , Indicates rounding up. and This indicates rounding down to the nearest integer.

[0117] Understandably, based on the first parameter Second parameter Determine the number of complete grains that can be captured by the maximum scanning field of view. When the maximum scanning field of view can acquire an image of at least one complete grain, set the width of the scanning field of view as the third parameter. With the first spacing The product of these parameters sets the height of the scanning field of view as the fourth parameter. With the second spacing The product of . When the maximum scanning field of view cannot acquire a complete grain, based on the first parameter. Second parameter Third parameter Or the fourth parameter Set the width and height of the scanning field of view.

[0118] Specifically, when FovX=1 and FovY=1, the scanning field of view can acquire an image of at least one complete grain. At this time, the width of the scanning field of view... Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is .

[0119] In other alternative embodiments, when FovX=1 and FovY=1, the scanning field of view can acquire an image of at least one complete grain. In this case, the width of the scanning field of view... Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is .

[0120] When FovX=1 and FovY>1, the maximum scanning field of view in the height direction cannot capture a complete grain, thus reducing the width of the scanning field of view. Set as: The height of the scanned field of view Set as: For each grain to be tested, the minimum step size of the scanning field of view in the height direction is set to... The minimum step size in the width direction is Furthermore, for each grain to be tested, at least [number] samples need to be collected in the height direction. The images are captured and stitched together to obtain a complete image of the grain under test.

[0121] When FovX > 1 and FovY = 1, the maximum scanning field of view in the width direction cannot capture a complete grain, thus reducing the width of the scanning field of view. Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: Set the minimum step size of the scanning field of view in the height direction as follows. Furthermore, for each grain to be tested, at least [number] samples need to be taken in the width direction. The images are captured and stitched together to obtain a complete image of the grain under test.

[0122] When FovX>1 and FovY>1, a complete grain cannot be captured in either the width or height direction of the maximum scanning field of view. Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is Furthermore, for each grain to be tested, at least [number] samples need to be taken in the width direction. At least [number] images were acquired in the height direction. The acquired images are stitched together to obtain a complete image of the grain under test.

[0123] It is understandable that this is used to achieve the maximum scanning width of the image acquisition device. Maximum scan height Resolution is and To calibrate fixed parameters. It is understandable that in order to detect smaller defects, higher resolution is required while sacrificing the maximum scanning field of view. If the maximum scanning field of view is used directly for image acquisition for any size of grain, defects may be missed. However, if the maximum resolution is used directly for image acquisition with the minimum scanning field of view, it may be impossible to acquire a complete grain image and cause the acquisition path to be chaotic.

[0124] Therefore, this embodiment adaptively adjusts the width and height of the scanning field of view based on the maximum scanning field of view and the grain size (i.e., the first spacing and the second spacing), and combines the planned scanning path to balance the quality and efficiency of image acquisition.

[0125] S105: Based on the reference coordinates of a die under test, the starting position of image acquisition is obtained, and the scanning path for wafer inspection is planned by combining the scanning field of view and the minimum movement step size. Specifically, this includes:

[0126] The scanning path includes scanning rows and scanning columns, controlling the movement of the scanning field of view along the height direction to scan at least a portion of the image of all the grains under test within the current scanning column;

[0127] Control the scanning field of view to move along the width direction to switch the scanning column of the scanning field of view, and control the scanning field of view to move along the height direction again to scan at least a portion of the image of all the test grains in the current scanning column;

[0128] Repeat the above operation to scan all the grains to be tested column by column.

[0129] The scanning path in this embodiment can be generally understood as an "S" shape. The first scanning column is set based on the reference coordinates of the die under test: the die closest to the wafer edge is used as the starting position for image acquisition (e.g., selecting the die closest to the left and top sides of the wafer), and the column containing this die is used as the first scanning column. It can be understood that when the maximum scanning field of view can acquire an image of at least one complete die, the first scanning column covers at least one complete die under test. When the maximum scanning field of view cannot acquire an image of a complete die in the width direction, the first scanning column covers a portion of the image of the die under test. That is, each die under test needs to pass through at least two scanning columns to achieve image acquisition.

[0130] Specifically, when FovX=1 and FovY=1, the scanning field of view can acquire an image of at least one complete grain. At this time, the width of the scanning field of view... Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is .

[0131] by Figure 4 For example, the width of the scanning field of view ,high The scanning field of view for image acquisition is shown in Figure 401. The minimum step size of the scanning field of view in the width direction is... The minimum step size for scanning the field of view in the height direction is .

[0132] Based on the layout of all the test dies on the wafer, the starting position of the scanning path and the first scanning column are determined based on the reference coordinates of the test die B1. The scanning field of view is controlled to move along the height direction to acquire images of all the test dies in the current scanning column.

[0133] Control the scanning field of view to move along the width direction to switch the scanning column of the scanning field of view, and then control the scanning field of view to move along the height direction, and scan all the grains to be tested column by column.

[0134] Furthermore, if the distance between two adjacent test grains in the width direction is less than or equal to the minimum moving step size of the scanning field of view in the width direction, or the distance between two adjacent test grains in the height direction is less than or equal to the minimum moving step size of the scanning field of view in the height direction, then images of at least two test grains can be acquired simultaneously in one scanning field of view.

[0135] for Figure 4 The wafer shown has B1-B6 as the test grains, and the scanning field width is... ,high Since die B1 is located closest to the left side of the wafer, the starting position for image acquisition is obtained based on the reference coordinates of die B1. Furthermore, the spacing between die B1 and die B2 in the width direction is less than the minimum step size of the scanning field of view in the width direction. Furthermore, the distance between grain B1 and grain B2 in the height direction is less than the minimum step size of the scanning field of view in the height direction. Therefore, image acquisition can be performed under the same scanning field of view. Similarly, it can be seen that grain B4 can also be acquired under the same scanning field of view.

[0136] Therefore, in the scanning path planned in this embodiment, the first image (i.e., the first scanning field of view) is as follows: Figure 4 As shown in image 41, image 41 contains grains B1, B2, and B4. During subsequent image processing, the image can be cropped based on the grain positions, and only the image of the grain to be tested will be processed.

[0137] Furthermore, in the scanning path planned in this embodiment, the second image is shown in image 43, which contains grain B3. Since images of all grains to be tested in the first scanning column have been acquired, the scanning field of view is controlled to move along the width direction to switch scanning columns. Then, the scanning field of view continues to move along the height direction to acquire images of grains B5 and B6 respectively. It can be understood that in this embodiment, the scanning path is divided into two columns. Because the image acquisition direction is flipped when switching scanning columns, the images of even-numbered scanning columns need to be flipped in subsequent image processing to obtain the target image of the grain to be tested.

[0138] It should be noted that image 42 is only used to represent the minimum moving step size of image acquisition (moving from image 41 to image 41). In this embodiment, the position shown in image 42 does not contain the grain to be tested, so image acquisition is not required at this position.

[0139] Furthermore, in other alternative embodiments, when FovX=1 and FovY=1, the scanning field of view can acquire an image of at least one complete grain. In this case, the width of the scanning field of view is directly set. Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is That is, each scanning field only acquires an image of one grain under test, further reducing the difficulty of image processing.

[0140] When FovX=1 and FovY>1, the maximum scanning field of view in the height direction cannot capture a complete grain, thus reducing the width of the scanning field of view. Set as: The height of the scanned field of view Set as: For each grain to be tested, the minimum step size of the scanning field of view in the height direction is set to... The minimum step size in the width direction is Furthermore, for each grain to be tested, at least [number] samples need to be collected in the height direction. The images are captured and stitched together to obtain a complete image of the grain under test.

[0141] like Figure 5 As shown, exemplarily, the width of the scanning field of view is... Set as: = The height of the scanned field of view Set as: (i.e., the scanning field of view for image acquisition) Figure 5 As shown in 501), the minimum step size of the scanning field of view in the height direction is set to... The minimum step size in the width direction is .

[0142] for Figure 5 In this embodiment, the spacing between grains B1 and B4 in the width direction is equal to the minimum step size of the scanning field of view in the width direction, thus allowing for acquisition under a unified scanning field of view. The calculation is 2, therefore, for grains B1 and B4, at least two images (i.e., image 51 and image 52) need to be acquired in the height direction. The scan path planned in this embodiment (e.g.) Figure 5 As indicated by the middle arrow, the scanning field of view controlling image acquisition moves along the height direction, and sequentially acquires images 51, 52, 53, 54, 55, and 56. Combined with... Figure 5 As shown, images of all the test grains in the current scanning column have been acquired. Then, the scanning field of view is controlled to move along the width direction to switch the scanning column. The scanning field of view is then controlled to move along the height direction to acquire the image corresponding to grain B5 (images 57 and 58).

[0143] It is understandable that by stitching together images 51 and 52, images of the test grains B1 and B4 can be obtained, and by cropping the stitched images, images of grains B1 and B4 can be obtained separately.

[0144] Furthermore, in other alternative embodiments, when the maximum scanning field of view in the height direction cannot capture a complete grain, the height of the scanning field of view is adjusted. Set as Overlapping area with longitudinal direction The sum of And keep the minimum movement step size unchanged. With this setting, for grain B1, images 51 and 52 will have overlapping parts. In subsequent image processing, when stitching in the height direction, the overlapping areas will be merged and stitched together.

[0145] It is understandable that when multiple images are stitched together to form a complete image of a single grain, errors such as motion errors in the image acquisition device, uniformity errors in the light source, or distortion errors in the camera may cause significant differences in grayscale and misalignment at the stitching point, resulting in obvious stitching marks. In the alternative embodiment of this invention, by setting an overlapping area and combining it with an image fusion processing algorithm (finding the stitching point based on feature point matching and then performing grayscale fusion at the stitching point), stitching marks are avoided.

[0146] It is understood that image fusion processing algorithms are well known in the prior art, and therefore will not be described in detail here. Any known or unknown image fusion processing algorithm may be used without restriction.

[0147] When FovX > 1 and FovY = 1, the maximum scanning field of view in the width direction cannot capture a complete grain, thus reducing the width of the scanning field of view. Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: Set the minimum step size of the scanning field of view in the height direction as follows. Furthermore, for each grain to be tested, at least [number] samples need to be taken in the width direction. The images are captured and stitched together to obtain a complete image of the grain under test.

[0148] like Figure 6 As shown, exemplarily, the width of the scanning field of view is... Set as: The height of the scanned field of view Set as: (i.e., the scanning field of view parameter for image acquisition) Figure 6 (As shown in 601). The minimum step size for the scanning field of view in the height direction is set to... The minimum step size in the width direction is .

[0149] In this embodiment The calculation is 2, therefore for grain B1, at least 2 images need to be acquired in the width direction (i.e., image 61 and image 64).

[0150] In the scanning path planned in this embodiment, the scanning field of view for image acquisition is controlled to move along the height direction, and images 61 and 62 are acquired sequentially. The scanning field of view is controlled to move along the height direction to acquire partial images of all the test dies located in the current scanning column. Then, the scanning field of view is controlled to move along the width direction to switch scanning columns. The scanning field of view is then controlled to move along the height direction again to acquire the remaining images of dies B2 and B1 (i.e., images 63 and 64). In summary, the scanning path for image acquisition in this embodiment is: image 61-image 62-image 63-image 64-image 65-image 66-image 67-image 68. The images located in even-numbered scanning columns are flipped (e.g., images 63, 64, 67, and 68). Then, the partial images corresponding to each test die are stitched together and cropped to obtain the complete images of the test dies.

[0151] Furthermore, in other alternative embodiments, when the maximum scanning field of view in the width direction cannot capture a complete grain, the width of the scanning field of view is reduced. Set as Horizontal overlapping area The sum of And keep the minimum movement step size unchanged. With this setting, for grain B1, images 61 and 64 will have overlapping parts. In subsequent image processing, when stitching in the height direction, the overlapping areas will be merged and stitched together to obtain the complete image of grain B1.

[0152] When FovX>1 and FovY>1, a complete grain cannot be captured in either the width or height direction of the maximum scanning field of view. Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is Furthermore, for each grain to be tested, at least [number] samples need to be taken in the width direction. At least [number] images were acquired in the height direction. The acquired images are stitched together to obtain a complete image of the grain under test.

[0153] In this embodiment The calculation is 2. The calculation is 2, meaning that at least 2 images need to be acquired in the width direction and at least 2 images need to be acquired in the height direction. Therefore, for a single grain to be tested, four images need to be acquired and stitched together to obtain a complete image of the grain to be tested.

[0154] like Figure 7 As shown, exemplarily, the width of the scanning field of view is... Set as: The height of the scanned field of view Set as: (i.e., the scanning field of view parameters for image acquisition) Figure 7 (As shown in 701). The minimum step size for the scanning field of view in the height direction is set to... The minimum step size in the width direction is .

[0155] Combination Figure 7As shown, the planned scanning path in this embodiment is: Image 71-Image 72-Image 73-Image 74-Image 75-Image 76-Image 77-Image 78-Image 79-Image 80-Image 81-Image 82. The images located in even-numbered scan columns are flipped (e.g., Image 75-Image 76-Image 77-Image 78, Image 81, and Image 82). Then, the partial images corresponding to each grain under test are stitched together and cropped to obtain the complete images of the grains under test.

[0156] Furthermore, in other alternative embodiments, when the maximum scanning field of view in the width direction cannot capture a complete grain, the width of the scanning field of view is reduced. Set as Horizontal overlapping area The sum of The height of the scanned field of view Set as Overlapping area with longitudinal direction The sum of The minimum movement step size remains constant. During subsequent image processing, when stitching in the height direction, overlapping areas are merged and stitched together to obtain a complete image of the grain under test.

[0157] It is understood that the scanning path of this embodiment can detect the die under test at any location on the wafer. Based on the die's position coordinates and reference coordinates, it provides an accurate basis for moving the scanning field of view. The scanning path is regular and does not need to traverse all locations on the wafer, avoiding the massive amount of data caused by full inspection. Furthermore, this embodiment can detect the die under test of any size. By constructing a parameter set to adjust the width and height of the scanning field of view, it can also obtain complete images of large-sized dies through image stitching, greatly improving the compatibility of the image acquisition equipment.

[0158] Furthermore, this embodiment further includes, after step S103, the following step: correcting the first spacing and the second spacing. It is understood that the first spacing is the sum of the distance between two adjacent dies on the wafer in the width direction and the width of the template die, and the second spacing is the sum of the distance between two adjacent dies on the wafer in the height direction and the height of the template die. In the above steps, this embodiment uses a grid with a width of the first spacing and a height of the second spacing to represent the dies. However, the first and second spacings are obtained based on the template die and its adjacent dies. The distances or dimensions between the remaining dies on the wafer may have certain deviations. Therefore, this embodiment corrects the first and second spacings to make them more adaptable to representing all dies on the wafer, improving the accuracy of image acquisition and path planning in subsequent steps.

[0159] The specific modifications to the first and second spacings include:

[0160] Obtain the position coordinates of all grains on the wafer, including the maximum number of grains in the wafer width direction. Maximum number of grains in the height direction;

[0161] Obtain the reference coordinates of two dies located at the edge of the wafer in the width direction, and calculate the difference in the x-coordinates of the reference coordinates of these two wafer edge dies. Use the ratio between the difference in the x-coordinates and the number of dies in the width direction of the wafer as the corrected first spacing.

[0162] Obtain the reference coordinates of two dies located at the edge of the wafer in the height direction, and calculate the difference in y-coordinates between the actual reference coordinates of the two wafer edge dies. Use the ratio between the difference in y-coordinates and the number of dies in the height direction of the wafer as the corrected second spacing.

[0163] For example, based on the theoretical leftmost grain of the wafer ( Reference coordinates The approximate movement position of the image scanning field of view is determined, and the image scanning field of view is moved to above the leftmost die on the wafer. Then, based on the image acquisition results, the actual center coordinates of this die are obtained and updated. ;

[0164] Based on the theory of the rightmost grain of the wafer ( Reference coordinates The approximate movement position of the image scanning field of view is determined, and the image scanning field of view is moved to above the rightmost die on the wafer. Then, based on the image acquisition results, the actual center coordinates of this die are obtained and updated. Based on the updated Correct the first spacing ;

[0165] Similarly, based on the theory, the bottommost grain of the wafer ( Reference coordinates The approximate movement position of the image scanning field of view is determined, and the image scanning field of view is moved to above the bottommost die on the wafer. Then, based on the image acquisition results, the actual center coordinates of this die are obtained and updated. ;

[0166] Based on the theory of the topmost grain of the wafer ( Reference coordinates The approximate movement position of the image scanning field of view is determined, and the image scanning field of view is moved to above the topmost die on the wafer. Then, based on the image acquisition results, the actual center coordinates of this die are obtained and updated. Based on the updated Correct the second spacing .

[0167] In this embodiment, the layout of all the grains on the wafer can be calculated using the first spacing and the second spacing. Based on the grain layout on the wafer, the approximate position of the grains located at the edge of the wafer can be obtained. Based on the scanning field of view, the center coordinates of the grains at the edge of the wafer can be obtained, and the first spacing and the second spacing can be corrected to improve the detection accuracy.

[0168] like Figure 8 As shown in the embodiments of this disclosure, a wafer inspection apparatus is also provided, including:

[0169] The data acquisition module 801 is used to acquire first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain, and the second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain.

[0170] The coordinate construction module 802 is used to obtain the position coordinates of the test grain and the template grain in the first coordinate system to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data;

[0171] The data processing module 803 is used to obtain the reference coordinates of the die to be tested on the wafer based on the first reference data and the positional relationship;

[0172] The configuration module 804 is used to calculate the number of complete grains under the maximum scanning field of view based on the maximum scanning field of view, the first spacing and the second spacing of the image acquisition, and to set the scanning field of view and the minimum moving step size of the image acquisition based on the number of complete grains.

[0173] The path planning module 805 is used to obtain the starting position of image acquisition based on the reference coordinates of a die under test, and to plan the scanning path by combining the scanning field of view and the minimum moving step size.

[0174] This disclosure also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the sampling methods for wafer inspection described in the various embodiments of this specification.

[0175] Figure 9 A hardware structure diagram of an electronic device according to an embodiment of this specification is shown. Figure 9 As shown, the electronic device 90 may include at least one processor 91, a memory 92 (e.g., non-volatile memory), a main memory 93, and a communication interface 94, and the at least one processor 91, memory 92, main memory 93, and communication interface 94 are connected together via an internal bus 95. The at least one processor 91 executes at least one computer-readable instruction stored or encoded in the memory 92.

[0176] It should be understood that the computer-executable instructions stored in memory 92, when executed, cause at least one processor 91 to perform the above-described combinations in the various embodiments of this specification. Figure 1 The description includes various operations and functions.

[0177] In the embodiments of this specification, electronic device 90 may include, but is not limited to: personal computer, server computer, workstation, desktop computer, laptop computer, notebook computer, mobile electronic device, smartphone, tablet computer, cellular phone, personal digital assistant (PDA), handheld device, messaging device, wearable electronic device, consumer electronic device, etc.

[0178] This disclosure also provides a computer-readable medium carrying computer-executable instructions that, when executed by a processor, can be used to implement various operations and functions of the sampling methods for wafer inspection described in the various embodiments of this specification.

[0179] The computer-readable medium in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can 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 of a computer-readable storage medium may include, but are not limited to: 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, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0180] In this disclosure, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can transmit, propagate, or transfer a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless, wireline, optical fiber, RF, etc., or any suitable combination thereof.

[0181] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0182] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus, systems, and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0183] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0184] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A wafer inspection method, characterized in that, include: Obtain first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain. The position coordinates of the test grain and the template grain in a first coordinate system are obtained to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data; The reference coordinates of the die to be tested on the wafer are obtained based on the first reference data and the positional relationship. The number of complete chips under the maximum scanning field of view is calculated based on the maximum scanning field of view, the first spacing, and the second spacing of the image acquisition. The scanning field of view and the minimum moving step size of the image acquisition are set based on the number of complete chips. The maximum scanning field of view includes the maximum scanning width and the maximum scanning height. When the maximum scanning width is greater than or equal to the first spacing and the maximum scanning height is greater than or equal to the second spacing of the chips, the width of the scanning field of view is set based on the ratio of the maximum scanning width to the first spacing and the height of the scanning field of view is set based on the ratio of the maximum scanning height to the second spacing. When the maximum scanning width is less than the first spacing and / or the maximum scanning height is less than the second spacing, the width and / or height of the scanning field of view are set based on the ratio of the maximum scanning width to the first spacing, the ratio of the maximum scanning height to the second spacing, the ratio of the first spacing to the maximum scanning width, and / or the ratio of the second spacing to the maximum scanning height. The starting position for image acquisition is obtained based on the reference coordinates of a die to be tested, and the scanning path for wafer inspection is planned by combining the scanning field of view and the minimum moving step size.

2. The wafer inspection method according to claim 1, characterized in that, The wafer inspection method includes: First reference data is obtained based on the coordinate information of the template grain and the coordinate information of its adjacent grains. The adjacent grains are located in the extension direction of the diagonal of the template grain. The coordinate information of the template grain includes at least one pair of diagonal coordinates of the template grain. The coordinate information of the adjacent grains includes at least one angular coordinate of the adjacent grains, and the angular coordinates of the adjacent grains are located next to the diagonal coordinates.

3. The wafer inspection method according to claim 1, characterized in that, Obtain the position coordinates of the test grain and the template grain in a first coordinate system to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data, including: Based on the wafer size, wafer center coordinates, and first reference data, calculate the maximum number of grains in the four directions of the template grains, as well as the maximum number of grains in the wafer width direction and the maximum number of grains in the height direction. Construct a first coordinate system with the width direction as the x-axis and the height direction as the y-axis; The position coordinates of the template grain in the first coordinate system are obtained based on the maximum number of grains in the four directions of the template grain, and the grain at at least one position coordinate in the first coordinate system is taken as the grain to be tested. The positional relationship between the grain to be tested and the template grain is determined based on the position coordinates of the grain to be tested and the template grain in the first coordinate system.

4. The wafer inspection method according to claim 1, characterized in that, The wafer inspection method includes: Based on maximum scan width Maximum scan height First spacing Second spacing Construct a parameter set, the parameter set including: a first parameter Second parameter Third parameter The fourth parameter ; The number of grains that can be captured by the maximum scanning field of view is determined based on the first parameter and the second parameter; When the maximum scanning field of view can acquire an image of at least one complete grain, the width of the scanning field of view is set to the third parameter and the first spacing. The product of the second and third parameters sets the height of the scanning field of view to the product of the fourth parameter and the second spacing. The product; When the maximum scanning field of view cannot capture a complete grain, the width and height of the scanning field of view are set based on the first parameter, the second parameter, the third parameter and / or the fourth parameter.

5. The wafer inspection method according to claim 4, characterized in that, When FovX=1 and FovY=1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: The minimum step size for scanning the field of view in the width direction is The minimum step size for scanning the field of view in the height direction is ; and / or, When FovX=1 and FovY>1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: Set the minimum step size of the scanning field of view in the height direction as follows: ; and / or, When FovX > 1 and FovY = 1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is ; and / or, When FovX>1 and FovY>1, the width of the scanning field of view will be... Set as: The height of the scanned field of view Set as: Set the minimum step size of the scanning field of view in the width direction as follows: The minimum step size for scanning the field of view in the height direction is .

6. The wafer inspection method according to claim 4, characterized in that, When FovX > 1, the width of the scanning field of view will be increased. Set as The sum of the horizontally overlapping areas; and / or, When FovY > 1, the height of the scanned field of view will be... Set as The sum of the areas overlapping vertically.

7. The wafer inspection method according to claim 5, characterized in that, When FovX=1 and FovY=1, if the distance between two adjacent test grains in the width direction is less than or equal to the minimum moving step size of the scanning field in the width direction, and / or the distance between two adjacent test grains in the height direction is less than or equal to the minimum moving step size of the scanning field in the height direction, then complete images of at least two test grains are acquired simultaneously in one scanning field.

8. The wafer inspection method according to claim 1, characterized in that, The starting position for image acquisition is obtained based on the reference coordinates of a grain under test. The scanning path is then planned using the scanning field of view and the minimum step size, including: The scanning path includes scanning rows and scanning columns, and controls the scanning field of view to move along the height direction to scan at least a portion of the image of all the grains to be tested within the current scanning column; Control the scanning field of view to move along the width direction to switch the scanning column of the scanning field of view, and then control the scanning field of view to move along the height direction, and scan all the grains to be tested column by column.

9. The wafer inspection method according to claim 1, characterized in that, The wafer inspection method further includes: Obtain the position coordinates of all dies on the wafer, including the number of dies in the width direction and the number of dies in the height direction; Obtain the reference coordinates of two dies located at the edge of the wafer in the width direction, and calculate the x-coordinate difference between the reference coordinates of these two wafer edge dies. Use the ratio between the x-coordinate difference and the number of dies in the width direction of the wafer as the corrected first spacing. Obtain the reference coordinates of two dies located at the edge of the wafer in the height direction, and calculate the y-coordinate difference between the reference coordinates of the two wafer edge dies. Use the ratio between the y-coordinate difference and the number of dies in the height direction of the wafer as the corrected second spacing.

10. A wafer inspection apparatus, based on the wafer inspection method according to any one of claims 1 to 9, characterized in that, The device includes: The data acquisition module is used to acquire first reference data, which includes a first spacing, a second spacing, and reference coordinates of the template grain. The first spacing is the sum of the distance between two adjacent grains on the wafer in the width direction and the width of the template grain. The second spacing is the sum of the distance between two adjacent grains on the wafer in the height direction and the height of the template grain. A coordinate construction module is used to obtain the position coordinates of the test grain and the template grain in a first coordinate system to determine the positional relationship between the test grain and the template grain, wherein the first coordinate system is constructed based on the first reference data; The data processing module is used to obtain the reference coordinates of the die to be tested on the wafer based on the first reference data and the positional relationship; The configuration module is used to calculate the number of complete grains under the maximum scanning field of view based on the maximum scanning field of view, the first spacing and the second spacing of the image acquisition, and to set the scanning field of view and the minimum moving step size of the image acquisition based on the number of complete grains. The path planning module is used to obtain the starting position of image acquisition based on the reference coordinates of a die to be tested, and to plan the scanning path in combination with the scanning field of view and the minimum movement step size.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the wafer inspection method as described in any one of claims 1 to 9.

12. A computer-readable medium, characterized in that, The computer-readable medium carries computer-executable instructions, which, when executed by a processor, are used to implement the wafer inspection method as described in any one of claims 1 to 9.

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