Coordinate calibration method and related product
By establishing the correspondence between the original coordinates and the absolute coordinates, and using the absolute coordinates of neighboring points to determine the calibration absolute coordinates of the object under test without a graphic, the problem of low efficiency in coordinate calibration of the object under test without a graphic is solved, and efficient and simplified coordinate calibration is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-04
- Publication Date
- 2026-03-10
AI Technical Summary
In existing technologies, the coordinate calibration of objects without graphics is inefficient, and traditional methods rely on high-precision equipment such as SEM, which leads to complex processes and high costs.
By pre-establishing the correspondence between the original coordinates and the absolute coordinates, the absolute coordinates of the calibration point are determined using the absolute coordinates of the neighboring points of the coordinate point to be calibrated, thus avoiding the repeated use of high-precision equipment.
It improves the efficiency of coordinate calibration for objects without graphical representations, simplifies the process, and reduces costs.
Smart Images
Figure CN121639798A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor technology, and in particular to a coordinate calibration method and related products. Background Technology
[0002] In the semiconductor manufacturing process, coordinate alignment and position calibration of the test object are crucial for accurately detecting the location of defects.
[0003] Absolute coordinates refer to positional coordinates determined with a fixed origin as a reference, without relying on a reference object. Therefore, absolute coordinates can be used to ensure the consistency of defect location detection results between different devices. Traditional calibration methods often rely on patterns (alignment marks) on the test object (DUT) for coordinate matching, but for DUTs without patterns, the lack of identifiable features leads to calibration difficulties. For DUTs without patterns, existing technologies typically require high-precision equipment, such as a scanning electron microscope (SEM), to obtain absolute coordinates. However, this method is complex, resulting in low coordinate calibration efficiency for DUTs without patterns.
[0004] Therefore, how to improve the coordinate calibration efficiency of the object under test is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention
[0005] To address the aforementioned issues, this application provides a coordinate calibration method and related products. The method pre-establishes the correspondence between the original coordinates and the absolute coordinates, and determines the absolute coordinates of the point to be calibrated by using the absolute coordinates of the neighboring points of the point to be calibrated. This achieves coordinate calibration of the object under test, avoids repeated reliance on high-precision equipment, and improves the efficiency of coordinate calibration of the object under test.
[0006] In a first aspect, embodiments of this application provide a coordinate calibration method, including:
[0007] Determine the coordinate points to be calibrated on the test object;
[0008] Determine the target neighborhood points corresponding to the coordinate points to be calibrated in the original coordinate set;
[0009] The absolute coordinates of the target corresponding to the neighborhood points of the target are determined based on the calibration parameters; the calibration parameters record the correspondence between each original coordinate and the absolute coordinate in the original coordinate set;
[0010] The calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated are determined based on the target absolute coordinates.
[0011] Optionally, the coordinate calibration method further includes:
[0012] Determine the calibration material; the calibration material is the test object whose surface particle points meet preset requirements;
[0013] Based on the calibration object, construct the original coordinate set and the absolute coordinate set;
[0014] Calibration parameters are constructed based on the original coordinate set and the absolute coordinate set.
[0015] Optionally, constructing the original coordinate set and the absolute coordinate set based on the calibration object includes:
[0016] The absolute coordinates of each particle point on the calibration material are obtained using a scanning electron microscope, and an absolute coordinate set is constructed based on the absolute coordinates.
[0017] The original coordinates of each particle point on the calibration object are measured based on the calibration machine, and an original coordinate set is constructed based on the original coordinates.
[0018] Optionally, constructing calibration parameters based on the original coordinate set and the absolute coordinate set includes:
[0019] The correspondence between each original coordinate in the original coordinate set and each absolute coordinate in the absolute coordinate set is determined based on the feature matching algorithm.
[0020] Calibration parameters are constructed based on the aforementioned correspondence.
[0021] Optionally, determining the target neighborhood point corresponding to the coordinate point to be calibrated in the original coordinate set includes:
[0022] Determine the distance between each original coordinate in the original coordinate set and the coordinate point to be calibrated;
[0023] Based on the distance, at least four target original coordinates corresponding to the coordinate point to be calibrated are selected from the original coordinate set according to a preset selection rule;
[0024] The original coordinates of the target are determined as the target neighborhood points corresponding to the coordinate points to be calibrated.
[0025] Optionally, the step of selecting at least four target original coordinates corresponding to the coordinate point to be calibrated from the original coordinate set based on the distance and a preset selection rule includes:
[0026] Based on the distance, the original coordinates in the original coordinate set are sorted from nearest to farthest to obtain the target sequence;
[0027] The first four original coordinates in the target sequence are designated as the target original coordinates corresponding to the coordinate points to be calibrated.
[0028] Optionally, determining the calibration absolute coordinates corresponding to the coordinate point of the target to be calibrated based on the target absolute coordinates includes:
[0029] By combining the bilinear mapping formula, the target solution coefficients corresponding to the bilinear mapping formula are determined based on the target neighborhood points and the target absolute coordinates;
[0030] The calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated are determined based on the target solution coefficients.
[0031] Optionally, the expression for the bilinear mapping formula is:
[0032] ;
[0033] ;
[0034] X is the abscissa of the calibration absolute coordinates, and Y is the ordinate of the calibration absolute coordinates. Solve for the coefficients for the first objective. Solve for the coefficients for the second objective. Solve for the coefficients for the third objective. Solve for the coefficients for the fourth objective. Solve for the coefficients for the fifth objective. Solve for the coefficients of the sixth objective. Solve for the coefficients of the seventh objective. Solve for the coefficients of the eighth objective. The original x-coordinate of the target coordinate point to be calibrated. The original ordinate of the target coordinate point to be calibrated is given.
[0035] Secondly, embodiments of this application provide a coordinate calibration device, comprising:
[0036] The first determining module is used to determine the coordinate points to be calibrated on the test object to be calibrated.
[0037] The second determining module is used to determine the target neighborhood point corresponding to the coordinate point to be calibrated in the original coordinate set;
[0038] The third determining module is used to determine the target absolute coordinates corresponding to the target neighborhood points based on calibration parameters; the calibration parameters record the correspondence between each original coordinate and absolute coordinate in the original coordinate set;
[0039] The fourth determining module is used to determine the calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated based on the target absolute coordinates.
[0040] Thirdly, embodiments of this application provide a coordinate calibration device, including:
[0041] Memory, used to store computer programs;
[0042] A processor for implementing the coordinate calibration method as described above when executing the computer program.
[0043] Fourthly, embodiments of this application provide a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the coordinate calibration method described above.
[0044] As can be seen from the above technical solutions, compared with the prior art, this application has the following advantages:
[0045] This application provides a coordinate calibration method that first determines the coordinate points to be calibrated on the object under test. Then, it identifies target neighborhood points corresponding to the coordinate points to be calibrated within the original coordinate set, and determines the target absolute coordinates corresponding to these neighborhood points based on calibration parameters. The calibration parameters record the correspondence between each original coordinate and its absolute coordinate in the original coordinate set. Finally, it determines the calibration absolute coordinates corresponding to the target coordinate point based on the target absolute coordinates. In this way, by pre-establishing the correspondence between original coordinates and absolute coordinates, and determining the absolute coordinates of the coordinate points to be calibrated using the absolute coordinates of their neighborhood points, the coordinate calibration of the object under test is achieved. This avoids repeated reliance on high-precision equipment and improves the efficiency of coordinate calibration. Attached Figure Description
[0046] Figure 1 A flowchart illustrating a coordinate calibration method provided in this application embodiment;
[0047] Figure 2 A schematic diagram of a particle provided in an embodiment of this application;
[0048] Figure 3 A schematic diagram showing the comparison between original coordinates and absolute coordinates provided in an embodiment of this application;
[0049] Figure 4 This is a schematic diagram of the structure of a coordinate calibration device provided in an embodiment of this application. Detailed Implementation
[0050] As mentioned earlier, existing coordinate calibration methods suffer from low calibration efficiency. Specifically, for objects under test without graphic representations, the lack of identifiable features makes traditional methods relying on graphic representations on the object difficult to implement. Furthermore, methods using high-precision equipment, such as SEM, to obtain absolute coordinates are complex and costly, further contributing to the low efficiency of coordinate calibration for objects without graphic representations.
[0051] To address the aforementioned problems, this application provides a coordinate calibration method. First, the coordinate points to be calibrated on the object to be calibrated are determined. Then, target neighborhood points corresponding to the coordinate points to be calibrated are determined from the original coordinate set, and target absolute coordinates corresponding to the target neighborhood points are determined based on calibration parameters. The calibration parameters record the correspondence between each original coordinate and its absolute coordinate in the original coordinate set. Finally, calibration absolute coordinates corresponding to the target coordinate points to be calibrated are determined based on the target absolute coordinates.
[0052] In this way, the correspondence between the original coordinates and the absolute coordinates is pre-established, and the absolute coordinates of the coordinate point to be calibrated are determined by the absolute coordinates of the neighboring points of the coordinate point to be calibrated, so as to realize the coordinate calibration of the object under test, avoid repeated reliance on high-precision equipment, and improve the coordinate calibration efficiency of the object under test.
[0053] It should be noted that the coordinate calibration method and related products provided in this application can be applied to the field of semiconductor technology. The above are merely examples and do not limit the application areas of the coordinate calibration method and related products provided in this application.
[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0055] Figure 1 This is a flowchart illustrating a coordinate calibration method provided in an embodiment of this application. (In conjunction with...) Figure 1 As shown in the embodiments of this application, a coordinate calibration method may include:
[0056] S101: Determine the coordinate points to be calibrated on the test object.
[0057] In practical applications, the object under test (DUT) can be an object without alignment marks. Taking a wafer as an example, the DUT can be a bare die or a wafer with special processes. The coordinate point to be calibrated can be any pixel on the DUT. In the embodiments of this application, when performing coordinate calibration on a patternless DUT, it is first necessary to determine the DUT to be calibrated, such as a patternless wafer, and the coordinate point to be calibrated on the patternless wafer.
[0058] S102: Determine the target neighborhood point corresponding to the coordinate point to be calibrated in the original coordinate set.
[0059] In practical applications, continuing with the example of a patternless wafer as the test object, the original coordinate set records the measurement coordinates of all particle points on the calibration wafer (calibration object) obtained by the testing equipment during measurement; these are the original coordinates. Due to measurement errors and trigger delays in the equipment, there will be a certain offset between the original coordinates and the absolute coordinates. The coordinate points to be calibrated are usually not in the original coordinate set because the original coordinates in the original coordinate set can be directly determined to their corresponding absolute coordinates through preset calibration parameters, thereby achieving coordinate calibration. For the coordinate points to be calibrated that are not in the original coordinate set, this embodiment can use the idea of "estimating the unknown point (the calibration absolute coordinate corresponding to the coordinate point to be calibrated) based on the known point (the absolute coordinate corresponding to the known original coordinate)" to achieve coordinate calibration of the patternless wafer. Furthermore, to improve calibration accuracy, the selected known point can be a nearby neighbor point corresponding to the coordinate point to be calibrated in the original coordinate set, i.e., the target neighbor point.
[0060] Furthermore, since there are different ways to determine the target neighborhood points, this application embodiment can describe one possible determination method.
[0061] In one case, S102: Determine the target neighborhood point corresponding to the coordinate point to be calibrated in the original coordinate set, which may specifically include:
[0062] Determine the distance between each original coordinate in the original coordinate set and the coordinate point to be calibrated;
[0063] Based on the distance, at least four target original coordinates corresponding to the coordinate point to be calibrated are selected from the original coordinate set according to a preset selection rule;
[0064] The original coordinates of the target are determined as the target neighborhood points corresponding to the coordinate points to be calibrated.
[0065] In practical applications, the calibration absolute coordinates corresponding to the coordinate point to be calibrated can be calculated based on interpolation algorithms (e.g., bilinear interpolation). This requires at least four original coordinates and at least eight equations to solve for the corresponding eight target coefficients. Specifically, the distances between each original coordinate in the original coordinate set and the coordinate point to be calibrated can be determined first. Then, according to a preset selection rule, four original coordinates are selected from the original coordinate set as the target original coordinates corresponding to the coordinate point to be calibrated, i.e., target neighborhood points. The preset selection rule can be "select from original coordinates with a distance less than a certain threshold," "select from the original coordinates with the smallest distance," etc., and can be specifically set as needed. Taking the preset selection rule "select from original coordinates with a distance less than a certain threshold" as an example, assuming the threshold is 1.5, if there are 10 original coordinates in the original coordinate set whose distance to the coordinate point to be calibrated is less than 1.5, then any four original coordinates can be selected from these 10 original coordinates as target neighborhood points.
[0066] Furthermore, since the methods for selecting the original coordinates of the target are not entirely the same, this application embodiment can describe one possible selection method.
[0067] In one scenario, the step of selecting at least four target original coordinates corresponding to the coordinate point to be calibrated from the original coordinate set based on the distance and a preset selection rule includes:
[0068] Based on the distance, the original coordinates in the original coordinate set are sorted from nearest to farthest to obtain the target sequence;
[0069] The first four original coordinates in the target sequence are designated as the target original coordinates corresponding to the coordinate points to be calibrated.
[0070] In practical applications, to maximize calibration accuracy, target neighborhood points can be the nearest neighbors to the coordinate point to be calibrated in the original coordinate set. When selecting, the original coordinates in the original coordinate set can be sorted from nearest to farthest, resulting in a target sequence. Then, based on the required number (e.g., 4), the first 4 sorted original coordinates are selected as the target original coordinates corresponding to the coordinate point to be calibrated; that is, the selected 4 target original coordinates are the target neighborhood points corresponding to the coordinate point to be calibrated.
[0071] S103: Determine the absolute coordinates of the target corresponding to the target's neighborhood points based on the calibration parameters; the calibration parameters record the correspondence between each original coordinate and absolute coordinate in the original coordinate set.
[0072] In practical applications, calibration parameters are pre-set and contain the mapping relationship (correspondence) between each original coordinate and absolute coordinate in the original coordinate set. Therefore, the absolute coordinates of the target corresponding to the target's neighborhood points can be directly determined through the calibration parameters.
[0073] Furthermore, since the methods for constructing the correspondence between coordinates are not entirely the same, this application embodiment can describe one possible construction method.
[0074] In one case, the coordinate calibration method further includes:
[0075] Determine the calibration material; the calibration material is the test object whose surface particle points meet preset requirements;
[0076] Based on the calibration object, construct the original coordinate set and the absolute coordinate set;
[0077] Calibration parameters are constructed based on the original coordinate set and the absolute coordinate set.
[0078] Figure 2 This is a schematic diagram of a particle provided in an embodiment of this application, combined with... Figure 2 As shown, the calibration object is a non-graphical test object used to construct calibration parameters. Its surface needs to have uniform and densely packed particles, and these particles need to meet the characteristics of high contrast, uniform size, and a distribution density that covers the entire area of the test object. Furthermore, the calibration object is measured on both an actual testing machine and a high-precision device to obtain the corresponding original coordinate set and absolute coordinate set. Moreover, due to the measurement error of the actual testing machine, the same particle point on the calibration object will have two different coordinate values in the original coordinate set and the absolute coordinate set. Therefore, there is a one-to-one correspondence between the original coordinates in the original coordinate set and the absolute coordinates in the absolute coordinate set. Based on this, a one-to-one correspondence is established between the coordinate points in the original coordinate set and the absolute coordinate set, thereby generating the calibration parameters.
[0079] Furthermore, since the methods for constructing the original coordinate set and the absolute coordinate set are not entirely the same, this application embodiment can describe one possible construction method.
[0080] In one instance, constructing the original coordinate set and the absolute coordinate set based on the calibration object includes:
[0081] The absolute coordinates of each particle point on the calibration material are obtained using a scanning electron microscope, and an absolute coordinate set is constructed based on the absolute coordinates.
[0082] The original coordinates of each particle point on the calibration object are measured based on the calibration machine, and an original coordinate set is constructed based on the original coordinates.
[0083] In practical applications, the calibration object can first be placed under a scanning electron microscope to obtain the absolute coordinates of each particle on the calibration object through high-resolution imaging. These absolute coordinates are then compiled into a set, denoted as the absolute coordinate set. Next, the calibration object is placed on the calibration instrument (e.g., an optical inspection instrument) to measure the original coordinates of each particle on the calibration object. These original coordinates are then compiled into a set, denoted as the original coordinate set. It is understandable that due to measurement errors and trigger delays inherent in optical inspection instruments, the original coordinates and absolute coordinates of the same particle on the calibration wafer are usually different.
[0084] Furthermore, since the methods for constructing calibration parameters are not entirely the same, this application embodiment can describe one possible construction method.
[0085] In one case, constructing calibration parameters based on the original coordinate set and the absolute coordinate set includes:
[0086] The correspondence between each original coordinate in the original coordinate set and each absolute coordinate in the absolute coordinate set is determined based on the feature matching algorithm.
[0087] Calibration parameters are constructed based on the aforementioned correspondence.
[0088] Figure 3 This is a schematic diagram comparing raw coordinates and absolute coordinates provided in an embodiment of this application. (In conjunction with...) Figure 3 As shown, the blue circles represent the original coordinates, and the red dots represent the absolute coordinates. When zoomed in locally, each original coordinate has a unique corresponding absolute coordinate, but there are coordinate differences between the two. When constructing calibration parameters, since the triggering of the moving platform (stage) in the calibration equipment is relatively precise, the deviation between the original coordinates and absolute coordinates of the same particle point in the calibration object will not be too large. To this end, this application introduces a nearest neighbor matching algorithm to find a one-to-one matching relationship between the original coordinate set and the absolute coordinate set. For example, A1(1,1)→B1(1,2), A2(2,2)→B2(2,3), and A2(3,3)→B2(3,4), etc. Here, A1, A2, and A3 are any three different original coordinates in the original coordinate set, and B1, B2, and B3 are three different absolute coordinates in the absolute coordinate set that correspond to A1, A2, and A3, respectively. It can be understood that there are usually as many such one-to-one correspondences as there are particles on the calibration object.
[0089] S104: Determine the calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated based on the target absolute coordinates.
[0090] In practical applications, interpolation algorithms are used to estimate unknown points based on known points. In this embodiment, an interpolation algorithm can be introduced to determine unknown points (the calibration absolute coordinates corresponding to the target coordinates to be calibrated) based on known points (the target absolute coordinates corresponding to the original target coordinates).
[0091] Furthermore, since the methods for determining the absolute coordinates of calibration are not entirely the same, this application embodiment can describe one possible determination method.
[0092] In one scenario, S104: Determine the calibration absolute coordinates corresponding to the coordinate point of the target to be calibrated based on the target absolute coordinates, which may specifically include:
[0093] By combining the bilinear mapping formula, the target solution coefficients corresponding to the bilinear mapping formula are determined based on the target neighborhood points and the target absolute coordinates;
[0094] The calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated are determined based on the target solution coefficients.
[0095] Furthermore, the expression for the bilinear mapping formula is:
[0096] ;
[0097] ;
[0098] X is the abscissa of the calibration absolute coordinates, and Y is the ordinate of the calibration absolute coordinates. Solve for the coefficients for the first objective. Solve for the coefficients for the second objective. Solve for the coefficients for the third objective. Solve for the coefficients for the fourth objective. Solve for the coefficients for the fifth objective. Solve for the coefficients of the sixth objective. Solve for the coefficients of the seventh objective. Solve for the coefficients of the eighth objective. The original x-coordinate of the target coordinate point to be calibrated. The original ordinate of the target coordinate point to be calibrated is given.
[0099] In practical applications, the bilinear interpolation algorithm can be used to calculate the calibration absolute coordinates corresponding to the target coordinate points. Specifically, the coordinates of the target's neighboring points and the target's absolute coordinates are first substituted into the bilinear mapping formula to solve for the target's coefficients. The corresponding bilinear mapping formula can be expressed as: and Where X is the x-coordinate in the calibration absolute coordinate system, and Y is the y-coordinate in the calibration absolute coordinate system. Solve for the coefficients for the first objective. Solve for the coefficients for the second objective. Solve for the coefficients for the third objective. Solve for the coefficients for the fourth objective. Solve for the coefficients for the fifth objective. Solve for the coefficients of the sixth objective. Solve for the coefficients of the seventh objective. Solve for the coefficients of the eighth objective. The original x-coordinate of the target point to be calibrated. Here are the original ordinates of the target point to be calibrated. Therefore, at least four neighboring points of the target need to be selected, and eight equations need to be constructed based on their corresponding absolute target coordinates to solve the problem. , , , , , , ,as well as These are the eight target solution parameters. Based on these parameters, the coordinates of the target to be calibrated are substituted into the bilinear mapping formula to obtain the calibration absolute coordinates. For example, suppose the coordinates of four selected target neighborhood points are (1,1), (2,3), (3,3), and (4,4), with corresponding absolute coordinates of (1,2), (2,3), (3,4), and (4,5). Then, the calibration absolute coordinates can be obtained using the bilinear mapping formula. , , , , , , ,as well as The values are 0, 1, 0, 0, 1, 1, 0, and 0, respectively. Furthermore, if the coordinate point to be calibrated is (7,7), then substituting it into the bilinear mapping formula yields the corresponding absolute calibration coordinates as (7,8).
[0100] In summary, the coordinate calibration method provided in this application first determines the coordinate point to be calibrated on the object to be calibrated. Then, it determines the target neighborhood points corresponding to the coordinate points to be calibrated within the original coordinate set, and determines the target absolute coordinates corresponding to the target neighborhood points based on calibration parameters. The calibration parameters record the correspondence between each original coordinate and absolute coordinate in the original coordinate set. Finally, it determines the calibration absolute coordinates corresponding to the target coordinate point to be calibrated based on the target absolute coordinates. In this way, by pre-establishing the correspondence between original coordinates and absolute coordinates, and determining the absolute coordinates corresponding to the coordinate points to be calibrated using the absolute coordinates corresponding to the neighborhood points of the coordinate points to be calibrated, the coordinate calibration of the object to be calibrated is achieved, avoiding repeated reliance on high-precision equipment and improving the efficiency of coordinate calibration.
[0101] Figure 4 This is a schematic diagram of a coordinate calibration device provided in an embodiment of this application. (In conjunction with...) Figure 4 As shown in the embodiment of this application, a coordinate calibration device 400 includes:
[0102] The first determining module 401 is used to determine the coordinate points to be calibrated on the test object to be calibrated;
[0103] The second determining module 402 is used to determine the target neighborhood point corresponding to the coordinate point to be calibrated in the original coordinate set;
[0104] The third determining module 403 is used to determine the target absolute coordinates corresponding to the target neighborhood points based on calibration parameters; the calibration parameters record the correspondence between each original coordinate and absolute coordinate in the original coordinate set;
[0105] The fourth determining module 404 is used to determine the calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated based on the target absolute coordinates.
[0106] As one implementation method, regarding how to construct calibration parameters, the coordinate calibration device 400 further includes:
[0107] The first determination submodule is used to determine the calibration object; the calibration object is the test object whose surface particle points meet preset requirements;
[0108] The first construction module is used to construct an original coordinate set and an absolute coordinate set based on the calibration object;
[0109] The second construction module is used to construct calibration parameters based on the original coordinate set and the absolute coordinate set.
[0110] As one implementation method, regarding how to construct the original coordinate set and the absolute coordinate set based on the calibration object, the first construction module mentioned above is specifically used for:
[0111] The absolute coordinates of each particle point on the calibration material are obtained using a scanning electron microscope, and an absolute coordinate set is constructed based on the absolute coordinates.
[0112] The original coordinates of each particle point on the calibration object are measured based on the calibration machine, and an original coordinate set is constructed based on the original coordinates.
[0113] As one implementation method, regarding how to construct calibration parameters based on the original coordinate set and the absolute coordinate set, the second construction module mentioned above is specifically used for:
[0114] The correspondence between each original coordinate in the original coordinate set and each absolute coordinate in the absolute coordinate set is determined based on the feature matching algorithm.
[0115] Calibration parameters are constructed based on the aforementioned correspondence.
[0116] As one implementation method, regarding how to determine the target neighborhood points corresponding to the coordinate points to be calibrated in the original coordinate set, the second determining module 402 is specifically used for:
[0117] Determine the distance between each original coordinate in the original coordinate set and the coordinate point to be calibrated;
[0118] Based on the distance, at least four target original coordinates corresponding to the coordinate point to be calibrated are selected from the original coordinate set according to a preset selection rule;
[0119] The original coordinates of the target are determined as the target neighborhood points corresponding to the coordinate points to be calibrated.
[0120] Furthermore, the step of combining the distance and selecting at least four target original coordinates corresponding to the coordinate point to be calibrated from the original coordinate set based on a preset selection rule may specifically include:
[0121] Based on the distance, the original coordinates in the original coordinate set are sorted from nearest to farthest to obtain the target sequence;
[0122] The first four original coordinates in the target sequence are designated as the target original coordinates corresponding to the coordinate points to be calibrated.
[0123] As one implementation method, regarding how to determine the calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated based on the target absolute coordinates, the aforementioned fourth determining module 404 is specifically used for:
[0124] By combining the bilinear mapping formula, the target solution coefficients corresponding to the bilinear mapping formula are determined based on the target neighborhood points and the target absolute coordinates;
[0125] The calibration absolute coordinates corresponding to the coordinate points of the target to be calibrated are determined based on the target solution coefficients.
[0126] Furthermore, the expression for the bilinear mapping formula is:
[0127] ;
[0128] ;
[0129] X is the abscissa of the calibration absolute coordinates, and Y is the ordinate of the calibration absolute coordinates. Solve for the coefficients for the first objective. Solve for the coefficients for the second objective. Solve for the coefficients for the third objective. Solve for the coefficients for the fourth objective. Solve for the coefficients for the fifth objective. Solve for the coefficients of the sixth objective. Solve for the coefficients of the seventh objective. Solve for the coefficients of the eighth objective. The original x-coordinate of the target coordinate point to be calibrated. The original ordinate of the target coordinate point to be calibrated is given.
[0130] In summary, this application first determines the coordinate points to be calibrated on the test object. Then, it identifies target neighborhood points corresponding to the coordinate points to be calibrated within the original coordinate set, and determines the target absolute coordinates corresponding to these neighborhood points based on calibration parameters. The calibration parameters record the correspondence between each original coordinate and its absolute coordinate in the original coordinate set. Finally, it determines the calibration absolute coordinates corresponding to the target coordinate point to be calibrated based on the target absolute coordinates. In this way, by pre-establishing the correspondence between original coordinates and absolute coordinates, and determining the absolute coordinates of the coordinate points to be calibrated using the absolute coordinates of their neighborhood points, the coordinate calibration of the test object is achieved, avoiding repeated reliance on high-precision equipment and improving the efficiency of coordinate calibration.
[0131] In addition, this application also provides a coordinate calibration device, including: a memory for storing a computer program; and a processor for executing the computer program to implement the coordinate calibration method described above.
[0132] In addition, this application also provides a readable storage medium storing a computer program that, when executed by a processor, implements the steps of the coordinate calibration method described above.
[0133] This application can also be used to detect contamination defects in glass covers and back panels in mobile phones, to detect contamination defects in glass substrates, polarizers, and touch screen surfaces in displays, to detect contaminants and damage on the surfaces of substrates and molding compounds in semiconductor packages, to detect contamination on the surfaces of solar cells, and to detect contamination on the surfaces of optical components.
[0134] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A coordinate calibration method characterized by, The coordinate calibration method comprises: determining a to-be-calibrated coordinate point on a to-be-measured object to be calibrated; determining a target neighborhood point corresponding to the to-be-calibrated coordinate point in an original coordinate set; determining a target absolute coordinate corresponding to the target neighborhood point based on a calibration parameter; the calibration parameter records a corresponding relationship between each original coordinate in the original coordinate set and an absolute coordinate; determining a calibration absolute coordinate corresponding to the to-be-calibrated coordinate point based on the target absolute coordinate.
2. The coordinate calibration method of claim 1, wherein, The coordinate calibration method further comprises: determining a calibration object; the calibration object is a to-be-measured object whose surface particle points meet preset requirements; constructing an original coordinate set and an absolute coordinate set based on the calibration object; constructing a calibration parameter based on the original coordinate set and the absolute coordinate set.
3. The coordinate calibration method of claim 2, wherein, The construction of the original coordinate set and the absolute coordinate set based on the calibration object comprises: obtaining absolute coordinates of each particle point on the calibration object based on a scanning electron microscope, and constructing an absolute coordinate set based on the absolute coordinates; measuring original coordinates of each particle point on the calibration object based on a to-be-calibrated machine, and constructing an original coordinate set based on the original coordinates.
4. The coordinate calibration method of claim 2, wherein, The construction of the calibration parameter based on the original coordinate set and the absolute coordinate set comprises: determining a corresponding relationship between each original coordinate in the original coordinate set and each absolute coordinate in the absolute coordinate set based on a feature matching algorithm; constructing a calibration parameter based on the corresponding relationship.
5. The coordinate calibration method of claim 1, wherein, The determination of the target neighborhood point corresponding to the to-be-calibrated coordinate point in the original coordinate set comprises: determining distances between each original coordinate in the original coordinate set and the to-be-calibrated coordinate point; selecting at least four target original coordinates corresponding to the to-be-calibrated coordinate point from the original coordinate set based on a preset selection rule in combination with the distances; determining the target original coordinates as the target neighborhood point corresponding to the to-be-calibrated coordinate point.
6. The coordinate calibration method of claim 1, wherein, The selection of the at least four target original coordinates corresponding to the to-be-calibrated coordinate point from the original coordinate set based on the preset selection rule in combination with the distances comprises: sorting each original coordinate in the original coordinate set based on the distances from near to far, and obtaining a target sequence; marking the first four original coordinates in the target sequence as the target original coordinates corresponding to the to-be-calibrated coordinate point.
7. The coordinate calibration method of claim 1, wherein, The determination of the calibration absolute coordinate corresponding to the to-be-calibrated coordinate point based on the target absolute coordinate comprises: determining a target solving coefficient corresponding to a bilinear mapping formula based on the target neighborhood point and the target absolute coordinate in combination with the bilinear mapping formula; determining the calibration absolute coordinate corresponding to the to-be-calibrated coordinate point based on the target solving coefficient.
8. The coordinate calibration method of claim 7, wherein, The expression of the bilinear mapping formula is: ； ； X is the horizontal coordinate in the calibration absolute coordinate, Y is the vertical coordinate in the calibration absolute coordinate, solving the coefficients for the first target, solving the coefficients for the second target, solving the coefficients for the third target, solving the coefficients for the fourth target, solving the coefficients for the fifth target, solving the coefficients for the sixth target, solving the coefficients for the seventh target, solving the coefficients for the eighth target, is the original horizontal coordinate of the target coordinate point to be calibrated, is the original vertical coordinate of the target coordinate point to be calibrated.
9. A coordinate calibration apparatus characterized by comprising: comprises: a first determining module configured to determine a to-be-calibrated coordinate point on a to-be-measured object to be calibrated; a second determining module configured to determine a target neighborhood point corresponding to the to-be-calibrated coordinate point in an original coordinate set; a third determining module configured to determine a target absolute coordinate corresponding to the target neighborhood point based on a calibration parameter; the calibration parameter records a corresponding relationship between each original coordinate in the original coordinate set and an absolute coordinate; A fourth determining module is configured to determine a calibration absolute coordinate corresponding to the target coordinate point to be calibrated based on the target absolute coordinate.
10. A coordinate calibration apparatus, characterized by comprising: The application further provides a computer readable storage medium having stored thereon a computer program. The application further provides a computer readable storage medium having stored thereon a computer program. The application further provides a computer readable storage medium having stored thereon a computer program.
11. A readable storage medium, characterized by,