Algorithm, system and device for obtaining key size of pattern, storage medium and computer program product

Abstract

An algorithm, system and device for obtaining a pattern critical dimension, a storage medium, and a computer program product, the algorithm comprising: providing a to-be-measured pattern, the to-be-measured pattern comprising a to-be-measured pattern having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the to-be-measured pattern; in the line width direction of the to-be-measured pattern, a measurement frame crossing the to-be-measured pattern is arranged, and the reference measurement position is located in the measurement frame; setting a plurality of measurement points along the boundary of the to-be-measured graph in the measurement frame; obtaining a first key size of the to-be-measured graph under the corresponding measurement point; acquiring a critical dimension curve graph of the to-be-measured graph based on the first critical dimension; acquiring a distribution mode of the critical dimension curve graph; and acquiring a second critical dimension of the reference measurement position based on the distribution mode and a rule for acquiring the critical dimension of the reference measurement position in the distribution mode. And the accuracy of obtaining the second key size of the reference measurement position is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to an algorithm and system, device and storage medium, and computer program product for obtaining key dimensions of a pattern. Background Technology

[0002] The core idea of ​​current algorithms for obtaining key dimensions of patterns is to acquire multiple measurement values ​​at corresponding measurement points within the measurement frame and measurement points. Then, based on these multiple measurement values ​​within the measurement height range, algorithms such as taking the maximum (Max), minimum (Min), or average (Mean) value are used to obtain the key dimensions of the specific graphic. The reference measurement position is located at the center of the measured pattern. By measuring key dimensions at multiple measurement points and obtaining values ​​through testing algorithms, the key dimensions corresponding to the reference measurement position are obtained.

[0003] As semiconductor process nodes become smaller and the pattern density increases significantly, the critical dimensions output by taking Max / Min / Mean will always deviate from the actual critical dimensions at the reference measurement location.

[0004] Currently, the accuracy of the actual critical dimensions at the location of the benchmark measurement position still needs to be improved. Summary of the Invention

[0005] The problem solved by the embodiments of the present invention is to provide an algorithm, system, device, storage medium, and computer program product for obtaining key dimensions of a pattern, which is beneficial to further improve the accuracy of obtaining the second key dimension of the reference measurement position.

[0006] To address the aforementioned problems, this invention provides an algorithm for obtaining key dimensions of a pattern, comprising: providing a pattern to be measured, the pattern to be measured including a graphic to be measured, the graphic to be measured having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the graphic to be measured; setting a measurement frame spanning the graphic to be measured in the line width direction of the graphic to be measured, the reference measurement position being located within the measurement frame; setting multiple measurement points along the boundary of the graphic to be measured within the measurement frame; obtaining a first key dimension of the graphic to be measured at the corresponding measurement points; obtaining a key dimension curve of the graphic to be measured based on the first key dimension; obtaining a distribution pattern of the key dimension curve; and obtaining a second key dimension of the reference measurement position based on the distribution pattern and the rules for obtaining the key dimension of the reference measurement position under the distribution pattern.

[0007] Optionally, in the step of providing the pattern to be tested, the reference measurement position extends along the line width direction of the pattern to be tested, and the reference measurement position passes through the center point of the pattern to be tested.

[0008] Optionally, in the step of providing the test pattern, the test pattern has a first boundary and a second boundary opposite to it in a direction perpendicular to the line width direction of the test pattern; the step of setting multiple measurement points along the boundary of the test pattern in the measurement frame includes: setting multiple first measurement points on the first boundary; extending a line from the first measurement point to the second boundary in a direction parallel to the line width direction of the test pattern, taking the first measurement point as a reference point, and taking the intersection of the extension line and the second boundary as the second measurement point, wherein the first measurement point and the second measurement point constitute the measurement point.

[0009] Optionally, the distance between adjacent measurement points is equal in a direction perpendicular to the line width direction of the graphic to be measured.

[0010] Optionally, the first critical dimension of the pattern under test at the corresponding measurement point can be obtained by scanning electron microscopy.

[0011] Optionally, in the step of setting multiple measurement points, in a direction perpendicular to the line width direction, the measurement point located on one side of the reference measurement position has a first spacing with the reference measurement position, and the measurement point located on the other side of the reference measurement position has a second spacing with the reference measurement position; the step of obtaining the key dimension curve of the graphic to be measured based on the first key dimension includes: taking the reference measurement position as the origin of the coordinate system, taking the extension direction of the reference measurement position as the Y-axis, and along a direction perpendicular to the extension direction of the reference measurement position, using the measurement frame... The edge line is used as the X-axis to form a curved coordinate line; the first spacing corresponding to each measurement point is used as the abscissa on the positive X-axis, and the first key dimension corresponding to each measurement point is used as the ordinate to form multiple first coordinate points on the coordinate system; the second spacing corresponding to each measurement point is used as the abscissa on the negative X-axis, and the first key dimension corresponding to each measurement point is used as the ordinate to form multiple second coordinate points on the coordinate system; a line is formed on the coordinate system that passes through the first coordinate points and the second coordinate points in sequence, and the line is used as the key dimension curve of the graphic to be measured.

[0012] Optionally, the step of obtaining the key dimensions of the reference measurement position based on the distribution pattern and the rules for obtaining the key dimensions of the reference measurement position under the distribution pattern includes: obtaining the first key dimensions corresponding to the measurement points within the ideal range values ​​on both sides of the reference measurement position; calculating the average value of multiple first key dimensions; and obtaining the second key dimension of the reference measurement position includes: using the average value of the dimensions obtained in the average value calculation as the second key dimension of the reference measurement position; or, the step of obtaining the key dimensions of the reference measurement position based on the distribution pattern and the rules for obtaining the key dimensions of the reference measurement position under the distribution pattern includes: obtaining the first key dimensions corresponding to the measurement points within the ideal range values ​​on both sides of the reference measurement position; selecting the maximum value among multiple first key dimensions; and obtaining the second key dimension of the reference measurement position includes: using the selected maximum value as the second key dimension of the reference measurement position.

[0013] Optionally, in the step of obtaining the first key dimension corresponding to the measurement points within the ideal range on both sides of the reference measurement position, the number of measurement points within the ideal range on both sides of the reference measurement position is equal.

[0014] Optionally, the step of obtaining the distribution pattern of the key dimension curve includes: obtaining the number of peaks in the key dimension curve based on the key dimension curve, and obtaining the distribution pattern of the key dimension curve based on the number of peaks.

[0015] Optionally, the step of obtaining the distribution pattern of the critical dimension curve based on the number of peaks includes: when the number of peaks is one, the distribution pattern of the critical dimension curve is a single-peak distribution pattern; when the number of peaks is multiple, the distribution pattern of the critical dimension curve is a multi-peak distribution pattern; and when the number of peaks is zero, the distribution pattern of the critical dimension curve is a zero-peak distribution pattern.

[0016] Optionally, when the distribution mode is a single-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: obtaining the first key dimensions corresponding to the measurement points within a first ideal range value on both sides of the reference measurement position; selecting the maximum value among multiple first key dimensions; or, when the distribution mode is a multi-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: obtaining the first key dimensions corresponding to the measurement points within a second ideal range value on both sides of the reference measurement position; calculating the average value of multiple first key dimensions; or, when the distribution mode is a zero-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: obtaining the first key dimensions corresponding to the measurement points within a third ideal range value on both sides of the reference measurement position; calculating the average value of multiple first key dimensions.

[0017] Optionally, both the first and third ideal range values ​​are 25%; the second ideal range value is 35%.

[0018] Accordingly, embodiments of the present invention also provide a system for obtaining key dimensions of a pattern, comprising: a providing module for providing a pattern to be measured, the pattern to be measured including a graphic to be measured, the graphic to be measured having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the graphic to be measured; a first setting module for setting a measurement frame spanning the graphic to be measured in the line width direction of the graphic to be measured, the reference measurement position being located within the measurement frame; a second setting module for setting multiple measurement points along the boundary of the graphic to be measured within the measurement frame; a first obtaining module for obtaining a first key dimension of the graphic to be measured at the corresponding measurement points; a second obtaining module for obtaining a key dimension curve of the graphic to be measured based on the first key dimension; a third obtaining module for obtaining a distribution pattern of the key dimension curve; and a fourth obtaining module for obtaining a second key dimension of the reference measurement position based on the distribution pattern and the rules for obtaining the key dimension of the reference measurement position under the distribution pattern.

[0019] Accordingly, embodiments of the present invention also provide a device including at least one memory and at least one processor, wherein the memory stores one or more computer instructions, and the one or more computer instructions are executed by the processor to implement the algorithm for obtaining key dimensions of a pattern provided in embodiments of the present invention.

[0020] Accordingly, embodiments of the present invention also provide a storage medium storing one or more computer instructions, which are used to implement the algorithm for obtaining key dimensions of a pattern provided in embodiments of the present invention.

[0021] Accordingly, embodiments of the present invention also provide a computer program product, including computer instructions, which, when executed by a processor, are used to implement the algorithm for obtaining key dimensions of a pattern provided in embodiments of the present invention.

[0022] Compared with the prior art, the technical solution of the embodiments of the present invention has the following advantages:

[0023] This invention provides an algorithm for obtaining key dimensions of a pattern. A measurement frame is set across the linewidth direction of the pattern to be measured. A reference measurement position is located within the measurement frame. Multiple measurement points are set along the boundary of the pattern to be measured within the measurement frame. A first key dimension of the pattern to be measured is obtained at the corresponding measurement point. Based on the first key dimension, a key dimension curve of the pattern to be measured is obtained. The distribution pattern of the key dimension curve is obtained. Based on the distribution pattern and the rules for obtaining the key dimension of the reference measurement position under the distribution pattern, a second key dimension of the reference measurement position is obtained. In other words, by using the distribution pattern of the key dimension curve, supplemented by the rules for obtaining the key dimension of the reference measurement position under the distribution pattern, the accuracy of obtaining the second key dimension of the reference measurement position is improved. Attached Figure Description

[0024] Figure 1 This is a flowchart of an embodiment of the algorithm for obtaining key dimensions of a pattern according to the present invention;

[0025] Figures 2 to 5 This is a schematic diagram of each step in one embodiment of the algorithm for obtaining key dimensions of a pattern according to the present invention;

[0026] Figure 6 This is a functional block diagram of an embodiment of the system for obtaining key dimensions of a pattern according to the present invention;

[0027] Figure 7 This is a hardware structure diagram of an embodiment of the device provided by the present invention. Detailed Implementation

[0028] As can be seen from the background technology, the accuracy of the actual critical dimensions at the location of the reference measurement position still needs to be improved.

[0029] To address the technical problem, embodiments of the present invention provide an algorithm for obtaining key dimensions of a pattern. (See reference...) Figure 1 The flowchart illustrates an embodiment of the algorithm for obtaining key dimensions of a pattern according to the present invention.

[0030] In this embodiment, the algorithm for obtaining the key dimensions of the pattern includes the following basic steps:

[0031] Step S1: Provide a pattern to be tested, the pattern to be tested includes a graphic to be tested, the graphic to be tested has a reference measurement position, and the extension direction of the reference measurement position is parallel to the line width direction of the graphic to be tested;

[0032] Step S2: In the line width direction of the graphic to be measured, a measurement frame spanning the graphic to be measured is set, and the reference measurement position is located in the measurement frame;

[0033] Step S3: In the measurement frame, set multiple measurement points along the boundary of the figure to be measured;

[0034] Step S4: Obtain the first key dimension of the graphic to be measured at the corresponding measurement point;

[0035] Step S5: Based on the first key dimension, obtain the key dimension curve of the graphic to be tested;

[0036] Step S6: Obtain the distribution pattern of the key dimension curve;

[0037] Step S7: Based on the distribution pattern and the rules for obtaining the key dimensions of the reference measurement position under the distribution pattern, obtain the second key dimension of the reference measurement position.

[0038] This invention provides an algorithm for obtaining key dimensions of a pattern. A measurement frame is set across the linewidth direction of the pattern to be measured. A reference measurement position is located within the measurement frame. Multiple measurement points are set along the boundary of the pattern to be measured within the measurement frame. A first key dimension of the pattern to be measured is obtained at the corresponding measurement point. Based on the first key dimension, a key dimension curve of the pattern to be measured is obtained. The distribution pattern of the key dimension curve is obtained. Based on the distribution pattern and the rules for obtaining the key dimension of the reference measurement position under the distribution pattern, a second key dimension of the reference measurement position is obtained. In other words, by using the distribution pattern of the key dimension curve, supplemented by the rules for obtaining the key dimension of the reference measurement position under the distribution pattern, the accuracy of obtaining the second key dimension of the reference measurement position can be improved.

[0039] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0040] Figures 2 to 5 This is a schematic diagram of each step in one embodiment of the algorithm for obtaining key dimensions of a pattern according to the present invention.

[0041] refer to Figure 2 Step S1: Provide a pattern to be tested, the pattern to be tested includes a graphic to be tested 101, the graphic to be tested 101 has a reference measurement position A, and the extension direction of the reference measurement position A is parallel to the line width direction of the graphic to be tested 101.

[0042] Specifically, the pattern to be measured 101 is used to provide a basis for subsequently obtaining the key dimensions of the reference measurement position A.

[0043] The reference measurement position A is used as the location for obtaining the second critical dimension, and is used to verify whether the dimensions obtained in the design phase are consistent with the second critical dimension obtained from the actual measurement.

[0044] It should be noted that the reference measurement position A is used as the position for obtaining the second key dimension. Therefore, the extension direction of the reference measurement position A is parallel to the line width direction of the measured pattern 101.

[0045] In this embodiment, in the step of providing the pattern to be tested, the reference measurement position A extends along the line width direction of the pattern to be tested 101, and the reference measurement position A passes through the center point of the pattern to be tested 101.

[0046] Specifically, the reference measurement position A passes through the center point of the measured pattern 101, so that the key dimension data obtained through the center point can represent the characteristics of the entire measured pattern 101.

[0047] In this embodiment, in the step of providing the test pattern 100, the test pattern 101 has a first boundary and a second boundary opposite to it in a direction perpendicular to the line width direction of the test pattern 101.

[0048] Specifically, the first boundary and the second boundary opposite it are used as the area for setting measurement points later.

[0049] refer to Figure 3 Step S2: In the line width direction of the graphic to be measured 101, a measurement frame 130 is set across the graphic to be measured 101, and the reference measurement position A is located in the measurement frame 130.

[0050] Specifically, the measurement frame 130 provides a standardized area for measurement. By setting the measurement frame 130 across the figure to be measured 101, random errors can be reduced and the accuracy of measurement can be improved.

[0051] Continue to refer to Figure 3 Step S3: In the measurement frame 130, multiple measurement points 150 are set along the boundary of the graphic to be measured 101.

[0052] Specifically, by setting measurement points 150, the first key dimension of the graphic 101 to be measured is facilitated. At the same time, by setting multiple measurement points 150 along the boundary of the graphic 101 to be measured, the automated measurement equipment can perform efficient measurement according to the predetermined path.

[0053] In this embodiment, the step of setting multiple measurement points 150 along the boundary of the graphic to be measured 101 in the measurement frame 130 includes: setting multiple first measurement points 150 on the first boundary; extending a line from the first measurement point 150 to the second boundary along a direction parallel to the line width direction of the graphic to be measured 101, taking the first measurement point 150 as a reference point, and taking the intersection of the extension line and the second boundary as the second measurement point 150, wherein the first measurement point 150 and the second measurement point 150 constitute the measurement point 150.

[0054] In this embodiment, the distance between adjacent measurement points 150 is equal in a direction perpendicular to the line width direction of the measured pattern 101.

[0055] Specifically, the distance between adjacent measurement points 150 is equal, so that the first and second boundaries of the measured pattern 101 are uniformly covered. At the same time, the equal distance between adjacent measurement points 150 helps to reduce deviations caused by improper selection of measurement points 150.

[0056] In this embodiment, in the step of setting multiple measurement points 150, in a direction perpendicular to the line width direction, the measurement point 150 located on one side of the reference measurement position A has a first distance from the reference measurement position A, and the measurement point 150 located on the other side of the reference measurement position A has a second distance from the reference measurement position A.

[0057] Specifically, the first and second spacings are used as the horizontal coordinates in the subsequent critical dimension curve.

[0058] Continue to refer to Figure 3 Step S4: Obtain the first key dimension of the graphic to be measured 101 at the corresponding measurement point 150.

[0059] Specifically, by obtaining the first key dimension of the graphic to be measured 101 at the corresponding measurement point 150, it is beneficial to obtain the second key dimension of the reference measurement position A through the acquisition rules of the key dimension of the reference measurement position A.

[0060] As an example, the first critical dimension of the pattern 101 under test at the corresponding measurement point 150 is obtained by scanning electron microscopy.

[0061] refer to Figure 4 Step S5: Based on the first key dimension, obtain the key dimension curve of the graphic to be tested 101.

[0062] It should be noted that by obtaining the key dimension curve of the graphic to be measured 101, it is beneficial to obtain the distribution pattern of the key dimension curve in the subsequent process, and to obtain the rule of the key dimension of the reference measurement position A according to the distribution pattern, and to obtain the second key dimension of the reference measurement position A, the accuracy of obtaining the second key dimension of the reference measurement position A can be improved.

[0063] In this embodiment, the step of obtaining the key dimension curve of the graphic to be measured 101 based on the first key dimension includes: forming a curve coordinate system with the reference measurement position A as the origin, the extension direction of the reference measurement position A as the Y-axis, and the edge line of the measurement frame 130 as the X-axis along a direction perpendicular to the extension direction of the reference measurement position A; forming a plurality of first coordinate points on the coordinate system with the first spacing corresponding to each measurement point 150 as the abscissa on the positive X-axis and the first key dimension corresponding to each measurement point 150 as the ordinate; forming a plurality of second coordinate points on the coordinate system with the second spacing corresponding to each measurement point 150 as the abscissa on the negative X-axis and the first key dimension corresponding to each measurement point 150 as the ordinate; forming a line on the coordinate system that passes through the first coordinate points and the second coordinate points in sequence, and using the line as the key dimension curve of the graphic to be measured 101.

[0064] Continue to refer to Figure 4 Step S6: Obtain the distribution pattern of the key dimension curve.

[0065] Specifically, by obtaining the distribution pattern of the key dimension curve, it is possible to select the rule of the key dimension of the reference measurement position A under different distribution patterns, thereby obtaining the second key dimension of the reference measurement position A.

[0066] In this embodiment, the step of obtaining the distribution pattern of the key dimension curve includes: obtaining the number of peaks in the key dimension curve based on the key dimension curve, and obtaining the distribution pattern of the key dimension curve based on the number of peaks.

[0067] As an example, the step of obtaining the distribution pattern of the critical dimension curve based on the number of peaks includes: when the number of peaks is one, the distribution pattern of the critical dimension curve is a single-peak distribution pattern; when the number of peaks is multiple, the distribution pattern of the critical dimension curve is a multi-peak distribution pattern; and when the number of peaks is zero, the distribution pattern of the critical dimension curve is a zero-peak distribution pattern.

[0068] It should be noted that the rules for the critical dimensions of the reference measurement position A are as follows for the single-wave distribution mode, multi-wave distribution mode, and zero-wave distribution mode.

[0069] It should also be noted that the zero-wave distribution pattern means there are no peaks, and the key dimension curve shows an increasing or decreasing trend on the X-axis.

[0070] refer to Figure 5 Step S7: Based on the distribution pattern and the rules of the key dimensions of the reference measurement position A under the distribution pattern, obtain the second key dimension of the reference measurement position A.

[0071] Specifically, based on different distribution patterns, selecting the rules for the key dimensions of the reference measurement location A under that distribution pattern can improve the accuracy of obtaining the second key dimension of the reference measurement location A and reduce the variance (σ) of the key dimensions of the reference measurement location A. 2 CD This reduces the root mean square (RMS) in the OPC model, thereby improving the accuracy of the OPC model.

[0072] In this embodiment, the rules based on the distribution pattern and the key dimensions of the reference measurement position A under the distribution pattern include: obtaining the first key dimensions corresponding to the measurement points 150 within the ideal range value B on both sides of the reference measurement position A; and calculating the average value of multiple first key dimensions.

[0073] Specifically, the ideal range value B on both sides of the reference measurement position A refers to the percentage of the number of ideal coordinate points on both sides of the origin in the positive and negative X-axis directions of the coordinate system, relative to the total number of coordinate points on the same side.

[0074] As an example, the step of obtaining the second critical dimension of the reference measurement position A includes: taking the average dimension obtained in the average value calculation as the second critical dimension of the reference measurement position A.

[0075] In other embodiments, the rules based on the distribution pattern and the key dimensions of the reference measurement position under the distribution pattern include: obtaining the first key dimension corresponding to the measurement point within the ideal range value on both sides of the reference measurement position; and selecting the maximum value among multiple first key dimensions.

[0076] Accordingly, the step of obtaining the second critical dimension of the reference measurement position includes: taking the selected maximum value as the second critical dimension of the reference measurement position.

[0077] In this embodiment, in the step of obtaining the first key dimension corresponding to the measurement point 150 within the ideal range on both sides of the reference measurement position A, the number of measurement points 150 within the ideal range on both sides of the reference measurement position A is equal.

[0078] Specifically, the number of measurement points 150 within the ideal range on both sides of the reference measurement position A is equal, which makes the accuracy of the second critical dimension of the reference measurement position A the highest.

[0079] As an example, such as Figure 5 As shown in (a), when the distribution mode is a single-wave distribution mode, the rules for the key dimensions of the reference measurement position A include: obtaining the first key dimensions corresponding to the measurement points 150 within the first ideal range on both sides of the reference measurement position A; and selecting the maximum value among multiple first key dimensions.

[0080] As an example, such as Figure 5 As shown in (b), when the distribution mode is a multi-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position A include: the first key dimensions corresponding to the measurement points 150 within the second ideal range values ​​on both sides of the reference measurement position A; and calculating the average value of multiple first key dimensions.

[0081] As an example, such as Figure 5 As shown in (c), when the distribution mode is the zero-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position A include: the first key dimensions corresponding to the measurement points 150 within the third ideal range value on both sides of the reference measurement position A; and calculating the average value of multiple first key dimensions.

[0082] It should be noted that in this embodiment, both the first ideal range value and the third ideal range value are 25%; the second ideal range value is 35%.

[0083] Accordingly, the present invention also provides a system for obtaining key dimensions of a pattern. Figure 6 This is a functional block diagram of the system for obtaining key dimensions of a pattern according to the present invention.

[0084] A system 200 for acquiring key dimensions of a pattern includes: a providing module 201 for providing a pattern to be measured, the pattern including a graphic to be measured, the graphic having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the graphic to be measured; a first setting module 202 for setting a measurement frame across the graphic to be measured in the line width direction, the reference measurement position being located within the measurement frame; a second setting module 203 for setting multiple measurement points along the boundary of the graphic to be measured within the measurement frame; a first acquisition module 204 for acquiring a first key dimension of the graphic to be measured at the corresponding measurement points; a second acquisition module 205 for acquiring a key dimension curve of the graphic to be measured based on the first key dimension; a third acquisition module 206 for acquiring a distribution pattern of the key dimension curve; and a fourth acquisition module 207 for acquiring a second key dimension of the reference measurement position based on the distribution pattern and the rules for acquiring the key dimension of the reference measurement position under the distribution pattern.

[0085] It should be noted that, based on the distribution pattern and the rules for obtaining the key dimensions of the reference measurement position under the distribution pattern, the second key dimension of the reference measurement position can be obtained. In other words, by using the distribution pattern of the key dimension curve and the rules for obtaining the key dimensions of the reference measurement position under the distribution pattern, the accuracy of obtaining the second key dimension of the reference measurement position can be improved.

[0086] Specifically, the pattern to be measured is used to provide a basis for obtaining key dimensions of the reference measurement position in the subsequent process.

[0087] The baseline measurement location serves as the location for subsequently obtaining the second critical dimension, and is used to verify whether the dimensions obtained during the design phase are consistent with the second critical dimension obtained from the actual measurements.

[0088] It should be noted that the reference measurement position is used to obtain the second key dimension, therefore, the extension direction of the reference measurement position is parallel to the line width direction of the graphic to be measured.

[0089] In this embodiment, in the step of providing the pattern to be tested, the reference measurement position extends along the line width direction of the pattern to be tested, and the reference measurement position passes through the center point of the pattern to be tested.

[0090] Specifically, the reference measurement position passes through the center point of the graphic to be measured, so that the key dimension data obtained through the center point can represent the characteristics of the entire graphic to be measured.

[0091] In this embodiment, during the step of providing the test pattern, the test pattern has a first boundary and a second boundary opposite to it in a direction perpendicular to the line width direction of the test pattern.

[0092] Specifically, the first boundary and the second boundary opposite it are used as the area for setting measurement points later.

[0093] The first setting module 202 is used to set the measurement frame. The measurement frame provides a standardized area for measurement. By setting the measurement frame that spans the figure to be measured, random errors can be reduced and the accuracy of measurement can be improved.

[0094] The second setting module 203 is used to set measurement points, which is beneficial for the first key dimension of the graphic to be measured. At the same time, multiple measurement points are set along the boundary of the graphic to be measured, which makes it easier for automated measurement equipment to perform efficient measurement according to a predetermined path.

[0095] In this embodiment, the step of setting multiple measurement points along the boundary of the graphic to be measured in the measurement frame includes: setting multiple first measurement points on the first boundary; extending a line from the first measurement point to the second boundary along a direction parallel to the line width direction of the graphic to be measured, taking the first measurement point as a reference point, and taking the intersection of the extension line and the second boundary as the second measurement point, wherein the first measurement point and the second measurement point constitute the measurement point.

[0096] In this embodiment, the distance between adjacent measurement points is equal in a direction perpendicular to the line width direction of the graphic to be measured.

[0097] Specifically, the distance between adjacent measurement points is equal, so that the first and second boundaries of the measured shape are uniformly covered. At the same time, the equal distance between adjacent measurement points helps to reduce deviations caused by improper selection of measurement points.

[0098] In this embodiment, in the step of setting multiple measurement points, in a direction perpendicular to the line width direction, the measurement point located on one side of the reference measurement position has a first distance from the reference measurement position, and the measurement point located on the other side of the reference measurement position has a second distance from the reference measurement position.

[0099] Specifically, the first and second spacings are used as the horizontal coordinates in the subsequent critical dimension curve.

[0100] The first acquisition module 204 is used to acquire the first key dimension of the graphic to be measured at the corresponding measurement point, which is beneficial to obtain the second key dimension of the reference measurement position through the acquisition rules of the key dimension of the reference measurement position.

[0101] As an example, the first critical dimension of the pattern under test at the corresponding measurement point is obtained by scanning electron microscopy.

[0102] The second acquisition module 205 is used to acquire the key dimension curve of the graphic to be measured, which is beneficial for subsequently acquiring the distribution pattern of the key dimension curve and the rule of acquiring the key dimension of the reference measurement position according to the distribution pattern, and to acquire the second key dimension of the reference measurement position, which can improve the accuracy of acquiring the second key dimension of the reference measurement position.

[0103] In this embodiment, the step of obtaining the key dimension curve of the graphic to be measured based on the first key dimension includes: forming a curve coordinate system with the reference measurement position as the origin, the extension direction of the reference measurement position as the Y-axis, and the edge line of the measurement frame as the X-axis along a direction perpendicular to the extension direction of the reference measurement position; forming multiple first coordinate points on the coordinate system with the first spacing corresponding to each measurement point as the abscissa on the positive X-axis and the first key dimension corresponding to each measurement point as the ordinate; forming multiple second coordinate points on the coordinate system with the second spacing corresponding to each measurement point as the abscissa on the negative X-axis and the first key dimension corresponding to each measurement point as the ordinate; forming a line on the coordinate system that passes sequentially through the first coordinate points and the second coordinate points, and using the line as the key dimension curve of the graphic to be measured.

[0104] The third acquisition module 206 is used to acquire the distribution pattern of the key dimension curve. Based on different distribution patterns, it can select the rule of the key dimension of the reference measurement position under the distribution pattern, thereby acquiring the second key dimension of the reference measurement position.

[0105] In this embodiment, the step of obtaining the distribution pattern of the key dimension curve includes: obtaining the number of peaks in the key dimension curve based on the key dimension curve, and obtaining the distribution pattern of the key dimension curve based on the number of peaks.

[0106] As an example, the step of obtaining the distribution pattern of the critical dimension curve based on the number of peaks includes: when the number of peaks is one, the distribution pattern of the critical dimension curve is a single-peak distribution pattern; when the number of peaks is multiple, the distribution pattern of the critical dimension curve is a multi-peak distribution pattern; and when the number of peaks is zero, the distribution pattern of the critical dimension curve is a zero-peak distribution pattern.

[0107] It should be noted that the rules for the critical dimensions of the reference measurement positions for the single-wave distribution mode, multi-wave distribution mode, and zero-wave distribution mode are as follows.

[0108] It should also be noted that the zero-wave distribution pattern means there are no peaks, and the key dimension curve shows an increasing or decreasing trend on the X-axis.

[0109] The fourth acquisition module 207 is used to acquire the second key dimension of the reference measurement position based on the distribution pattern and the rules of the key dimension of the reference measurement position under the distribution pattern.

[0110] Specifically, selecting the rules for the key dimensions of the reference measurement position based on different distribution patterns can improve the accuracy of obtaining the second key dimension of the reference measurement position and reduce the variance (σ) of the key dimensions of the reference measurement position. 2 CD This reduces the root mean square (RMS) in the OPC model, thereby improving the accuracy of the OPC model.

[0111] In this embodiment, the rules based on the distribution pattern and the key dimensions of the reference measurement position under the distribution pattern include: obtaining the first key dimensions corresponding to the measurement points within the ideal range values ​​on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions.

[0112] Specifically, the ideal range value on both sides of the reference measurement position refers to the percentage of the number of ideal coordinate points on both sides of the origin in the positive and negative X-axis directions of the coordinate system, relative to the total number of coordinate points on the same side.

[0113] As an example, the step of obtaining the second critical dimension of the reference measurement position includes: using the average dimension obtained in the average value calculation as the second critical dimension of the reference measurement position.

[0114] In other embodiments, the rules based on the distribution pattern and the key dimensions of the reference measurement position under the distribution pattern include: obtaining the first key dimension corresponding to the measurement point within the ideal range value on both sides of the reference measurement position; and selecting the maximum value among multiple first key dimensions.

[0115] Accordingly, the step of obtaining the second critical dimension of the reference measurement position includes: taking the selected maximum value as the second critical dimension of the reference measurement position.

[0116] In this embodiment, in the step of obtaining the first key dimension corresponding to the measurement points within the ideal range on both sides of the reference measurement position, the number of measurement points within the ideal range on both sides of the reference measurement position is equal.

[0117] Specifically, the number of measurement points within the ideal range on both sides of the reference measurement position is equal, which makes the accuracy of the second critical dimension of the reference measurement position the highest.

[0118] As an example, when the distribution mode is a single-wave distribution mode, the rules for the key dimensions of the reference measurement position include: obtaining the first key dimension corresponding to the measurement point within the first ideal range value on both sides of the reference measurement position; and selecting the maximum value among multiple first key dimensions.

[0119] As an example, when the distribution mode is a multi-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: the first key dimensions corresponding to the measurement points within the second ideal range values ​​on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions.

[0120] As an example, when the distribution mode is a zero-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: the first key dimension corresponding to the measurement point within the third ideal range value on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions.

[0121] It should be noted that in this embodiment, both the first ideal range value and the third ideal range value are 25%; the second ideal range value is 35%.

[0122] This invention also provides a device that can implement the algorithm for obtaining key dimensions of a pattern provided in this invention by loading a program, and an optional hardware structure of the terminal device provided in this invention can be as follows: Figure 7 As shown, it includes: at least one processor 01, at least one communication interface 02, at least one memory 03, and at least one communication bus 04.

[0123] In this embodiment, the number of processor 01, communication interface 02, memory 03, and communication bus 04 is at least one, and processor 01, communication interface 02, and memory 03 communicate with each other through communication bus 04. Communication interface 02 can be an interface of a communication module for network communication, such as the interface of a GSM module. Processor 01 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. Memory 03 may include high-speed RAM and may also include non-volatile memory (NVM), such as at least one disk storage device. Memory 03 stores one or more computer instructions, which are executed by processor 01 to implement the algorithm for obtaining key dimensions of a pattern provided in this embodiment of the present invention.

[0124] It should be noted that the aforementioned terminal device may also include other devices (not shown) that may not be essential to understanding the content disclosed in the embodiments of the present invention; given that these other devices may not be essential for understanding the content disclosed in the embodiments of the present invention, the embodiments of the present invention will not describe them one by one.

[0125] This invention also provides a storage medium storing one or more computer instructions for implementing the algorithm for obtaining key dimensions of a pattern provided in this invention.

[0126] Embodiments of the present invention can be implemented by various means, such as hardware, firmware, software, or combinations thereof. In a hardware configuration, the method according to an exemplary embodiment of the present invention can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, etc. In a firmware or software configuration, embodiments of the present invention can be implemented in the form of modules, processes, functions, etc. Software code can be stored in memory units and executed by a processor. The memory units are located inside or outside the processor and can send data to and receive data from the processor via various known means.

[0127] Accordingly, a computer program product includes computer instructions, which, when executed by a processor, are used to implement the algorithm for obtaining key dimensions of a pattern provided in the embodiments of the present invention.

[0128] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An algorithm for obtaining key dimensions of a pattern, characterized in that, include: A test pattern is provided, the test pattern including a test graphic, the test graphic having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the test graphic; A measurement frame spanning the graphic to be measured is set in the line width direction of the graphic to be measured, and the reference measurement position is located in the measurement frame; In the measurement frame, multiple measurement points are set along the boundary of the figure to be measured; Obtain the first key dimension of the graphic under test at the corresponding measurement point; Based on the first key dimension, obtain the key dimension curve of the graphic to be tested; Obtain the distribution pattern of the key dimension curve; Based on the distribution pattern and the rules governing the key dimensions of the reference measurement position under that distribution pattern, the second key dimension of the reference measurement position is obtained.

2. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, In the step of providing the pattern to be tested, the reference measurement position extends along the line width direction of the pattern to be tested, and the reference measurement position passes through the center point of the pattern to be tested.

3. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, In the step of providing the test pattern, the test pattern has a first boundary and a second boundary opposite to it in a direction perpendicular to the line width direction of the test pattern; The step of setting multiple measurement points along the boundary of the graphic to be measured in the measurement frame includes: setting multiple first measurement points on the first boundary; Along a direction parallel to the line width direction of the graphic to be measured, with the first measurement point as the reference point, an extension line is drawn towards the second boundary, and the intersection of the extension line and the second boundary is taken as the second measurement point. The first measurement point and the second measurement point constitute the measurement point.

4. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, In a direction perpendicular to the line width direction of the measured shape, the distance between adjacent measurement points is equal.

5. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, The first critical dimension of the pattern under test at the corresponding measurement point is obtained by scanning electron microscopy.

6. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, In the step of setting multiple measurement points, in a direction perpendicular to the line width direction, the measurement point located on one side of the reference measurement position has a first distance from the reference measurement position, and the measurement point located on the other side of the reference measurement position has a second distance from the reference measurement position. The step of obtaining the key dimension curve of the graphic to be measured based on the first key dimension includes: taking the reference measurement position as the origin of the coordinate system, taking the extension direction of the reference measurement position as the Y-axis, and taking the edge line of the measurement frame as the X-axis along the direction perpendicular to the extension direction of the reference measurement position; taking the first spacing corresponding to each measurement point as the abscissa on the positive X-axis, and taking the first key dimension corresponding to each measurement point as the ordinate, forming a plurality of first coordinate points on the coordinate system; Using the second spacing corresponding to each measurement point as the abscissa on the negative X-axis and the first key dimension corresponding to each measurement point as the ordinate, a plurality of second coordinate points are formed on the coordinate system; a line is formed on the coordinate system that passes through the first coordinate point and the second coordinate point in sequence, and the line is used as the key dimension curve of the graphic to be measured.

7. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, The rules based on the distribution pattern and the key dimensions of the reference measurement position under the distribution pattern include: obtaining the first key dimensions corresponding to the measurement points within the ideal range values ​​on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions. The step of obtaining the second critical dimension of the reference measurement position includes: using the average dimension obtained in the average value calculation as the second critical dimension of the reference measurement position; or, The rules based on the distribution pattern and the key dimensions of the reference measurement position under the distribution pattern include: obtaining the first key dimension corresponding to the measurement point within the ideal range value on both sides of the reference measurement position; and selecting the maximum value among multiple first key dimensions. The step of obtaining the second critical dimension of the reference measurement position includes: taking the selected maximum value as the second critical dimension of the reference measurement position.

8. The algorithm for obtaining key dimensions of a pattern as described in claim 7, characterized in that, In the step of obtaining the first key dimension corresponding to the measurement points within the ideal range on both sides of the reference measurement position, the number of measurement points within the ideal range on both sides of the reference measurement position is equal.

9. The algorithm for obtaining key dimensions of a pattern as described in claim 1, characterized in that, The steps for obtaining the distribution pattern of the key dimension curve include: obtaining the number of peaks in the key dimension curve based on the key dimension curve, and obtaining the distribution pattern of the key dimension curve based on the number of peaks.

10. The algorithm for obtaining key dimensions of a pattern as described in claim 9, characterized in that, The step of obtaining the distribution pattern of the critical dimension curve based on the number of peaks includes: when the number of peaks is one, the distribution pattern of the critical dimension curve is a single-peak distribution pattern; when the number of peaks is multiple, the distribution pattern of the critical dimension curve is a multi-peak distribution pattern; and when the number of peaks is zero, the distribution pattern of the critical dimension curve is a zero-peak distribution pattern.

11. The algorithm for obtaining key dimensions of a pattern as described in claim 10, characterized in that, When the distribution mode is a single-wave distribution mode, the rules for the key dimensions of the reference measurement position include: obtaining the first key dimension corresponding to the measurement point within the first ideal range value on both sides of the reference measurement position; and selecting the maximum value among multiple first key dimensions. or, When the distribution mode is a multi-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: the first key dimensions corresponding to the measurement points within the second ideal range values ​​on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions. or, When the distribution mode is a zero-wave distribution mode, the rules for obtaining the key dimensions of the reference measurement position include: the first key dimension corresponding to the measurement point within the third ideal range value on both sides of the reference measurement position; and calculating the average value of multiple first key dimensions.

12. The algorithm for obtaining key dimensions of a pattern as described in claim 10, characterized in that, The first and third ideal range values ​​are both 25%; the second ideal range value is 35%.

13. A system for obtaining key dimensions of a pattern, characterized in that, include: A module is provided for providing a pattern to be tested, the pattern to be tested including a graphic to be tested, the graphic to be tested having a reference measurement position, the extension direction of the reference measurement position being parallel to the line width direction of the graphic to be tested; The first setting module is used to set a measurement frame that spans the graphic to be measured in the line width direction, and the reference measurement position is located in the measurement frame. The second setting module is used to set multiple measurement points along the boundary of the graphic to be measured in the measurement frame; The first acquisition module is used to acquire the first key dimension of the graphic to be measured at the corresponding measurement point; The second acquisition module is used to acquire a key dimension curve of the graphic to be tested based on the first key dimension; The third acquisition module is used to acquire the distribution pattern of the key dimension curve; The fourth acquisition module is used to acquire the second key dimension of the reference measurement position based on the distribution pattern and the rules of the key dimensions of the reference measurement position under the distribution pattern.

14. A device, characterized in that, It includes at least one memory and at least one processor, the memory storing one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the algorithm for obtaining key dimensions of a pattern as described in any one of claims 1 to 12.

15. A storage medium, characterized in that, The storage medium stores one or more computer instructions, which are used to implement the algorithm for obtaining key dimensions of a pattern as described in any one of claims 1 to 12.

16. A computer program product, characterized in that, It includes computer instructions, which, when executed by a processor, are used to implement the algorithm for obtaining key dimensions of a pattern as described in any one of claims 1 to 12.

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