CN118050950A

CN118050950A - Lithographic pattern correction method, device and equipment

Info

Publication number: CN118050950A
Application number: CN202211425716.7A
Authority: CN
Inventors: 贺婷; 张迎春; 王占雨
Original assignee: Semiconductor Manufacturing International Shanghai Corp
Current assignee: Semiconductor Manufacturing International Shanghai Corp
Priority date: 2022-11-15
Filing date: 2022-11-15
Publication date: 2024-05-17

Abstract

The embodiment of the application provides a photoetching pattern correction method, device and equipment, wherein the method comprises the following steps: acquiring target reference image information and test image information, wherein the target reference image information is used for indicating a measurement graph and corresponding coordinates of a reference lithography image on a target layer of a mask, and the test image information is test image information of a test lithography graph obtained based on the mask, and the coordinates of the test lithography graph in the test image information have a mapping relation with the coordinates of the measurement graph; obtaining contour information corresponding to the test lithography pattern based on target reference image information and test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography pattern; and constructing a correction model according to the outline information of the test lithography pattern, and correcting the lithography pattern to be corrected on the mask plate by using the correction model. Thus, the technical scheme provided by the embodiment of the application can improve the accuracy of correcting the photoetching pattern by the correction model.

Description

Lithographic pattern correction method, device and equipment

Technical Field

The embodiment of the application relates to the technical field of semiconductors, in particular to a photoetching pattern correction method, device and equipment.

Background

With the continuous progress of integrated circuit design and manufacturing technology, the feature size is already close to or even smaller than the wavelength of light waves used in the photolithography process, so that in the photolithography process, due to diffraction and interference phenomena of light, certain deformation and deviation exist between a photolithography pattern obtained on an actual wafer and a mask pattern, and the error directly affects the circuit performance and the production yield.

The Optical Proximity Correction (OPC) method compensates for the deformation of the lithographic pattern generated in the lithographic process by changing the shape of the pattern on the reticle so that the resulting pattern on the wafer substantially coincides with the intended pattern is an effective method for eliminating such errors, with the most effective being the model-based OPC correction method.

However, in the model-based OPC correction method, the final lithographic pattern correction result obtained by using the correction model is not accurate and the correction effect is not ideal.

Therefore, how to improve the accuracy of correcting the photolithography patterns by the correction model is a technical problem to be solved.

Disclosure of Invention

The technical problem solved by the embodiment of the application is how to improve the accuracy of correcting the photoetching patterns by the correction model.

In order to solve the above problems, an embodiment of the present application provides a method for correcting a lithographic pattern, including:

Acquiring target reference image information and test image information, wherein the target reference image information is used for indicating a measurement graph and corresponding coordinates of a reference lithography image on a target layer of a mask, the test image information is test image information of a test lithography graph obtained based on the mask, and the coordinates of the test lithography graph in the test image information have a mapping relation with the coordinates of the measurement graph;

Obtaining contour information corresponding to the test lithography pattern based on the target reference image information and the test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography pattern;

and constructing a correction model according to the outline information of the test lithography pattern, and correcting the lithography pattern to be corrected on the mask plate by using the correction model.

Optionally, the obtaining contour information corresponding to the test lithography pattern based on the target reference image information and the test image information includes:

extracting the outline of the test lithography pattern in the test image information according to the gray value of the test image information to obtain first test outline information corresponding to the test lithography pattern, wherein the first test outline information comprises two-dimensional characteristic information of the test lithography pattern;

And overlapping the first test contour information with the edge of the measurement graph at the corresponding coordinate to obtain first alignment contour information, and obtaining contour information of the corresponding test lithography graph.

Optionally, the overlapping the first test contour information with the graphic edge of the target reference image information at the corresponding coordinate to obtain first alignment contour information includes:

determining a clipping view of the measurement graph at the corresponding coordinate in the target reference image information according to the coordinate of the test lithography graph to obtain a target clipping view;

and overlapping the first test contour information with the edge of the measurement graph at the corresponding coordinate in the target clipping view to obtain the first alignment contour information.

Optionally, the determining, according to the coordinates of the test lithography pattern, the clipping view of the measurement pattern at the corresponding coordinates in the target reference image information to obtain the target clipping view includes:

acquiring coordinates of the test lithography pattern;

and editing the target reference image information according to a preset size by taking the coordinates of the test photoetching graph as the center to obtain a view containing the measurement graph at the corresponding coordinates, and obtaining the target editing view.

Optionally, the overlapping the first test contour information with an edge of the measurement graph at a corresponding coordinate in the target clip view to obtain the first alignment contour information includes:

Determining a predetermined movement coordinate range of the target clip view;

moving the first test contour information within the preset moving coordinate range, and determining the overlapping rate of the side quantity graph at the corresponding coordinate in the first test contour information and the target clip view;

and when the overlapping rate reaches a preset overlapping value, obtaining the first test contour information.

Optionally, after the step of obtaining the first alignment profile information, before the step of obtaining the profile information corresponding to the test lithography pattern, the method further includes:

acquiring test image information containing the first alignment contour information;

Extracting a target contour intensity signal of the test photoetching pattern according to the intensity signal of the test image information to obtain second test contour information;

and fitting the second test contour information with the edge of the measurement graph at the corresponding coordinate to obtain second alignment contour information.

Optionally, extracting the target contour intensity signal corresponding to the test lithography pattern according to the intensity signal of the test image information to obtain second test contour information, including:

acquiring test image information containing the first test contour information, and determining an intensity signal of the test image information;

Determining an intensity signal meeting a target contour intensity signal threshold value in the intensity signals to obtain target contour intensity signals;

and extracting contour coordinates corresponding to the target contour intensity signal to obtain corresponding second test contour information.

Optionally, the fitting the second test contour information to the edge of the measurement pattern at the corresponding coordinate to obtain second alignment contour information includes:

Determining a measurement graph at a corresponding coordinate in a target clipping view of the target reference image information according to the coordinates of the second test contour information to obtain a target measurement graph;

Acquiring each contour coordinate of the second test contour information and each target contour coordinate of the target measurement graph;

Determining a first edge average error of the contour coordinates and the target contour coordinates in a first direction;

Determining a second edge average error of the contour coordinates and the target contour coordinates in a second direction, wherein the second direction is perpendicular to the first direction;

obtaining a first moving average value according to each first edge average error, and obtaining a second moving average value according to each second edge average error;

and moving the second test contour information in the first direction according to the first moving average value, and moving the second test contour information in the second direction according to the second moving average value so as to fit the second test contour information with the edge of the target measurement graph to obtain the second alignment contour information.

Optionally, the target reference image information includes feature size information of each measurement pattern, and after the step of obtaining the second alignment profile information, the method further includes:

measuring the characteristic dimension of the second alignment contour information to obtain contour characteristic dimension information;

Determining the characteristic dimension information of the measurement graph at the corresponding coordinate position by utilizing the coordinates of the second alignment contour information;

And matching the second alignment contour information by utilizing the contour feature size information and the feature size information.

Optionally, the matching of the second alignment profile information using the profile feature size information and the feature size information includes:

Determining the outline characteristic dimension information and each characteristic error of the characteristic dimension information to obtain a characteristic dimension information error mean value;

And when the characteristic dimension information error mean value is larger than a preset characteristic dimension information error value, adjusting the outline characteristic dimension information until the characteristic dimension information error mean value meets the preset characteristic dimension information error value, and completing the matching of the second alignment outline information.

Optionally, the adjusting the profile feature size information includes:

And reducing the outline characteristic dimension information by half of the characteristic dimension information error mean value.

Optionally, after the step of obtaining the second alignment profile information, the method further includes:

determining other second alignment contour information in the test image information corresponding to the second alignment contour information;

Obtaining the distance between the second alignment contour information and each piece of other second alignment contour information, and the distance between the second alignment contour information and the edge of the measurement graph at the corresponding coordinate in the target reference image information, so as to obtain a distance vector;

And judging the credibility of the second alignment contour information by using the distance vector to obtain a credible contour, and carrying out contour average on the credible contour to obtain the contour information.

Optionally, before the step of obtaining the profile information corresponding to the test lithography pattern based on the target reference image information and the test image information, the method further includes:

and acquiring a coordinate relation, wherein the coordinate relation is a mapping relation established by the coordinates of the measured photoetching pattern and the coordinates of the measured pattern in the test image information.

Optionally, after the step of obtaining the profile information corresponding to the test lithography pattern based on the target reference image information and the test image information, the method further includes:

and editing the contour information to obtain target contour editing information, wherein the target contour editing information comprises independent contour information for effectively correcting the photoetching graph to be corrected.

Optionally, after the step of clipping the profile information to obtain the target profile clipping information, the method further includes:

And carrying out corresponding weight configuration on the target contour clipping information to obtain target clipping contour weight information, wherein the target clipping contour weight information is used for representing the correction effect of each piece of target contour clipping information.

Optionally, the building a correction model according to the outline information of the test lithography pattern includes:

And constructing the correction model according to the contour information of the test photoetching graph, the target contour clipping information, the target clipping contour weight information and the target reference image information on the target layer.

Optionally, the test image information includes feature test image information with feature size information, and after the step of constructing the correction model according to the profile information of the test lithography, the target profile clipping information, the target clipping profile weight information, and the target reference image information on the target layer, the method further includes:

Verifying the correction model by utilizing the characteristic test image information, and obtaining the constructed correction model when the correction expected value is reached;

The correcting the to-be-corrected photoetching pattern on the mask plate by using the correcting model comprises the following steps:

and correcting the to-be-corrected photoetching pattern on the mask plate by using the constructed correction model.

Optionally, the acquiring the target reference image information and the test image information includes:

determining a target layer of the mask;

Performing measurement scanning on the reference photoetching image at the corresponding coordinate on the target layer to obtain a measurement graph on the target layer, and obtaining the target reference image information;

And carrying out measurement scanning on different areas containing the test lithography patterns on the mask plate to obtain the test image information, wherein the coordinates of the test lithography patterns in the test image information correspond to the coordinates of the measurement patterns.

Optionally, the performing measurement scanning on the different areas including the test lithography pattern on the mask plate to obtain the test image information includes:

And filtering the test image information which does not meet the extraction requirement of the image information to obtain filtered test image information, and obtaining the test image information.

The embodiment of the application also provides a photoetching pattern correction device, which comprises:

The image information acquisition module is suitable for acquiring target reference image information and test image information, wherein the target reference image information is used for indicating a measurement graph of a reference photoetching image and corresponding coordinates on a target layer of a mask, the test image information is test image information of a test photoetching graph obtained based on the mask, and the coordinates of the test photoetching graph in the test image information have a mapping relation with the coordinates of the measurement graph;

The contour information acquisition module is used for acquiring contour information corresponding to the test lithography graph based on the target reference image information and the test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography graph;

And the correction module is suitable for constructing a correction model according to the outline information of the test lithography pattern, and correcting the lithography pattern to be corrected on the mask plate by using the correction model.

The embodiment of the application also provides a lithographic pattern correction device, which comprises the lithographic pattern correction device according to the embodiment.

Compared with the prior art, the technical scheme of the embodiment of the application has the following advantages:

The photoetching pattern correction method provided by the embodiment of the application comprises the following steps: acquiring target reference image information and test image information, wherein the target reference image information is used for indicating a measurement pattern and corresponding coordinates of a reference lithography pattern on a target layer of a mask, the test image information is test image information of a test lithography pattern obtained based on the mask, and the coordinates of the test lithography pattern in the test image information have a mapping relation with the coordinates of the measurement pattern; obtaining contour information corresponding to the test lithography pattern based on the target reference image information and the test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography pattern; and constructing a correction model according to the outline information of the test lithography pattern, and correcting the lithography pattern to be corrected on the mask plate by using the correction model.

It can be seen that, according to the method for correcting the lithography pattern provided by the embodiment of the application, by utilizing the target reference image information and the test image information, the profile information containing the two-dimensional characteristic information corresponding to the test lithography pattern is obtained, and the two-dimensional characteristic information can enhance the integrity and reliability of the obtained profile of the test lithography pattern, so that the correction effect of the correction model constructed based on the profile information is ensured, the profile correction precision and accuracy of the correction model are improved, and the precision of correcting the lithography pattern by the OPC model is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic flow chart of a method for correcting a photolithography pattern according to an embodiment of the present application;

FIG. 2 is a schematic diagram of test image information according to an embodiment of the present application;

FIG. 3 is a schematic diagram of an extraction state of first test contour information according to an embodiment of the present application;

FIG. 4 is a schematic view of the alignment state of the first test profile information shown in FIG. 3;

FIG. 5 is a schematic diagram of a test lithography pattern corresponding to first alignment profile information according to an embodiment of the present application;

FIG. 6 is a schematic diagram of the intensity signal of the test pattern of FIG. 5;

FIG. 7 is a schematic diagram of a test lithographic pattern correspondingly obtained at the signal intensities shown in FIG. 6;

FIG. 8 is a diagram of a second test profile information of a lithographic pattern correction method according to an embodiment of the present application;

FIG. 9 is a schematic diagram showing a state of edge errors in the method for correcting a photolithography pattern according to the embodiment of the present application;

FIG. 10 is a schematic diagram showing a state of performing edge fitting on the second test contour information shown in FIG. 8;

FIG. 11 is a schematic diagram of a measurement pattern with feature size information for a lithographic pattern correction method according to an embodiment of the present application;

FIG. 12 is a schematic diagram of feature size information corresponding to one of the measurement patterns shown in FIG. 11;

FIG. 13 is a schematic illustration of profile feature size information of the second alignment profile information shown in FIG. 10;

FIG. 14 is a schematic illustration of a test lithographic pattern of two-dimensional features provided by an embodiment of the present application;

FIG. 15 is a schematic view of a state of the test pattern of FIG. 14 including an unreliable profile;

FIG. 16 is a schematic view of profile information extracted from the test lithographic pattern of FIG. 15;

FIG. 17 is a schematic diagram of averaging the profile information shown in FIG. 16;

FIG. 18 is a schematic diagram showing a result of filtering and contour averaging of unreliable contour information in a photolithography correction method according to embodiments of the present application;

FIG. 19 is a schematic diagram illustrating a process of filtering untrusted profile information in a lithographic pattern correction method according to an embodiment of the present application;

FIG. 20 is a schematic diagram of a process for trusted contour averaging in a lithographic pattern correction method according to an embodiment of the present application;

FIG. 21 is a schematic flow chart of a method for correcting a lithographic pattern according to an embodiment of the present application;

FIG. 22 is a diagram of target profile clip information in a method for lithographic pattern correction according to an embodiment of the present application;

FIG. 23 is a diagram showing the profile weight information of a target clip in a method for correcting a lithography pattern according to an embodiment of the present application;

FIG. 24 is a schematic diagram illustrating the construction and calibration of a correction model in a method for correcting a lithographic pattern according to an embodiment of the present application;

FIG. 25 is a schematic illustration of the corrective effect of a corrective model constructed by a conventional method;

FIG. 26 is a schematic diagram of a lithographic apparatus according to an embodiment of the application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Photolithography is a major process for integrated circuit fabrication, and is mainly used to transfer the photolithographic pattern on a reticle to the material of each layer on the wafer surface. With the continuous decrease of the feature sizes required by the integrated circuit manufacturing design requirements, the deformation and deviation between the photolithography patterns on the wafer and the photolithography patterns on the mask become more and more serious, and become an important factor affecting the wafer performance and the yield. Particularly, in the positions where the lithography patterns are adjacent to each other, due to obvious interference and diffraction effects of light waves, the deviation of the lithography patterns formed on the wafer through the mask plate is relatively large, and the lithography pattern positions are generally places which can play a key role on the electrical performance and circuit function of a circuit, thereby affecting the performance of the wafer and even causing the circuit to fail, and the phenomenon that the lithography patterns on the wafer deviate from the lithography patterns on the mask due to the diffraction and interference of the light waves is called optical proximity effect (OPE, optical proximity effect).

In the photolithography process, the optical proximity effect is unavoidable, so that corresponding measures are required to reduce the deformation and deviation of the photolithography pattern on the reticle to the photolithography pattern on the wafer as much as possible, so as to ensure the performance and yield of the wafer.

At present, a method is generally adopted, namely, yield-driven mask correction is added between traditional physical design and mask manufacturing, and the deformation of the photoetching patterns on the wafer generated in the photoetching process is compensated by changing the shape of the photoetching patterns on the mask, so that the photoetching patterns obtained by photoetching on the wafer basically accord with the photoetching patterns (expected patterns are patterns required by a design layout) on the mask.

The above-mentioned method for correcting the lithography pattern on the reticle is called a lithography enhancement technique, and one effective lithography enhancement technique that is commonly used is an optical proximity correction method (OPC, optical proximity cerrection), wherein the accuracy of the correction result of the model-based OPC correction method is high, so that it is necessary to construct a high-quality correction model.

Conventional methods of constructing high quality correction models require the accumulation of thousands of empirical data obtained by scanning electron microscope (CD-SEM, critical Dimension Scanning Electron Microscope) measurements of developed CDs (feature sizes) on the design layout, followed by extraction and conversion of the data into layout files. Various types of information, such as CD size, SEM scanning image, scanning line, SEM scanning outline, etc., can be output in the layout file obtained according to the CD-SEM measurement conversion. Thus, the CD-SEM can provide reliable one-dimensional feature measurement information with high accuracy and precision.

But when two-dimensional proximity features such as head-to-head, bar-to-bar, and line-to-line are involved, it can only acquire partial information from SEM images. For some asymmetric complex features, measurement data of the current position cannot be acquired. With the shrinking of design rules and the refinement of process windows, the complexity of the required two-dimensional features inevitably increases, and the correction accuracy of the correction model constructed in the prior art cannot meet the design requirements.

Therefore, in order to improve the accuracy of correcting the photoetching pattern by the correction model, the embodiment of the application provides a photoetching pattern correction method which is used for constructing a high-quality correction model so as to improve the correction effect of the photoetching pattern.

Referring to fig. 1, fig. 1 is a flow chart illustrating a photolithography pattern correction method according to an embodiment of the application.

As shown in the figure, the flow may include the steps of:

Step S001: target reference image information and test image information are acquired.

The target reference image information is used for indicating a measurement pattern and corresponding coordinates of a reference lithography pattern on a target layer of a mask, the test image information is test image information of a test lithography pattern obtained based on the mask, and the coordinates of the test lithography pattern in the test image information have a mapping relation with the coordinates of the measurement pattern.

Based on the foregoing, it is understood that in the model-based OPC correction method, the profile of the post-development CD measurement data obtained by the CD-SEM can be converted into a layout file and modeled when the correction model is constructed.

Therefore, the target reference image information may be: and determining that the layout file contains image information capable of effectively correcting the outline of the photoetching pattern on the mask plate according to the layout file converted from the outline of the design layout measured by the CD-SEM. The measurement pattern of the reference lithography pattern on the target layer for indicating the mask is the above.

Because the CD-SEM obtains the graph coordinates of the corresponding reference lithography graph when measuring the design layout, the target reference image information simultaneously comprises the measurement graph of the reference lithography graph and the corresponding coordinates.

The test image information may be: and obtaining image information containing different numbers of photoetching patterns on the mask plates according to different areas in the layout file. The test image information of the test lithography pattern obtained based on the mask is the above.

The layout file can contain measurement patterns of all reference lithography patterns on the target layer, coordinate information of the corresponding measurement patterns and image information of the lithography patterns on the mask plate in the design layout, so that the target reference image information and the test image information can be obtained according to the layout file.

Of course, the test image information and the target reference image information may be obtained using CD-SEM scanning.

For easy understanding of the scanned image obtained by CD-SEM, reference is made to FIG. 2. FIG. 2 is a schematic diagram of test image information provided in an embodiment of the present application.

It can be seen that the test image information 01 includes a plurality of test lithography patterns 02, and the test lithography patterns 02 are contour information to be extracted and calibrated for the construction of a subsequent correction model.

Specifically, in one embodiment, the process of acquiring the target reference image information and the test image information may include:

determining a target layer of the mask; performing measurement scanning on the reference photoetching image at the corresponding coordinate on the target layer to obtain a measurement graph on the target layer, and obtaining the target reference image information; and carrying out measurement scanning on different areas containing the test lithography patterns on the mask plate to obtain the test image information, wherein the coordinates of the test lithography patterns in the test image information correspond to the coordinates of the measurement patterns.

And determining a target layer of the mask, namely determining a layer containing a measurement pattern capable of being used for effectively calibrating the test lithography pattern, so that the test lithography pattern can be calibrated according to the measurement pattern in the target reference image information.

Thus, the image information required to be used is obtained based on the mature CD-SEM of the existing technology, so that the subsequent processing can be facilitated, and the processing efficiency is accelerated.

In order to ensure accuracy of the test image information for subsequent processing, in an embodiment, the process of performing measurement scanning on different areas including the test lithography pattern on the reticle to obtain the test image information may include: and filtering the test image information which does not meet the extraction requirement of the image information to obtain filtered test image information, and obtaining the test image information.

The image information extraction requirement refers to image information capable of effectively correcting a photoetching pattern to be corrected.

Because the CD-SEM scans different areas when scanning the mask, some test lithography patterns contained in the obtained test image information are distorted or some test lithography patterns are invalid to be corrected, and the test lithography patterns can not be effectively corrected and do not meet the image information extraction requirements, therefore, the test image information containing the test lithography patterns is filtered, the accuracy of the subsequent correction model construction can be enhanced, the processing capacity of the test image information is reduced, and the overall processing efficiency is improved.

The coordinates of the test lithography pattern in the test image information and the coordinates of the measurement pattern have a mapping relation, so that the test lithography pattern can be conveniently and rapidly corresponding to the measurement pattern during subsequent contour processing.

The test image information is used for acquiring contour information used for constructing the correction model, and the target reference image information is used for calibrating the contour information acquired based on the test image information so as to improve the reliability of the contour information used for constructing the correction model.

In order to facilitate rapid positioning of the measurement pattern in the target reference image information according to the coordinates of the test lithographic pattern, therefore, in one embodiment, the lithographic pattern correction method may further comprise, prior to the step of based on the target reference image information and the test image information:

Therefore, when a certain measurement lithography figure is obtained from the test image information, the corresponding measurement figure in the target reference image information can be quickly found according to the coordinates of the measurement lithography figure and in combination with the mapping relation in the coordinate relation, so that the processing efficiency of processing the measurement lithography figure is improved.

Step S002: and obtaining contour information corresponding to the test lithography pattern based on the target reference image information and the test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography pattern.

The two-dimensional characteristic information can fully embody the integrity and the correction effect of the extracted contour information, and improves the reliability of the extracted contour information, so that the reliability of the correction result of the correction model can be ensured after the correction model is constructed based on the contour information.

In order to be able to ensure the acquisition of high-precision, high-quality profile information, in one embodiment, step S002 may include:

The test image information is a gray scale image, and specifically reference may be made to fig. 3, and fig. 3 is a schematic diagram of an extraction state of the first test contour information according to an embodiment of the present application.

As can be seen from fig. 2, the test image information is a gray scale, the first test contour information 010 of the extracted test lithography pattern is a white rectangular structure bright area shown in fig. 3, the measurement pattern 10 for calibrating the first test contour information is a white deformed structure bright area shown in fig. 3, and the contour information enclosed by each white rectangular structure bright area needs to be extracted.

In the gray scale map, the pixel values of the black dark area and the white bright area are different, that is, the gray scale values are different, so that the first test contour information 010 can be obtained by extracting the gray scale values corresponding to the white rectangular structure bright area, the first test contour information 010 includes all contour information of the test lithography pattern, such as two-dimensional features (two-dimensional adjacent features) of the strip-to-strip, the head-to-head and the line segment-to-strip, that is, the parts easy to generate the optical adjacent effect are extracted, and the reliability of the extracted first test contour information 010 can be ensured.

Since the target reference image information includes all measurement patterns on the target layer, in order to quickly align with the measurement patterns in the target reference image information, in one embodiment, the process of overlapping the first test contour information with the pattern edges of the target reference image information at the corresponding coordinates to obtain the first alignment contour information may include:

Determining a clipping view of the measurement graph at the corresponding coordinate in the target reference image information according to the coordinate of the test lithography graph to obtain a target clipping view; and overlapping the first test contour information with the edge of the measurement graph at the corresponding coordinate in the target clipping view to obtain the first alignment contour information.

Referring specifically to fig. 4, fig. 4 is a schematic diagram showing an alignment state of the first test profile information shown in fig. 3.

As shown in the figure, it can be seen that after the profile information 010 (first test profile information) is extracted for the first time as shown in fig. 3, in order to ensure that the obtained first test profile information 010 is usable, the first test profile information 010 is overlapped with the corresponding measurement pattern 10 in the target reference image information, so that the reliability and accuracy of the first test profile information 010 can be improved.

In one embodiment, the determining, according to the coordinates of the test lithography pattern, the clip view of the measurement pattern at the corresponding coordinates in the target reference image information, to obtain the target clip view may include:

Acquiring coordinates of the test lithography pattern; and editing the target reference image information according to a preset size by taking the coordinates of the test photoetching graph as the center to obtain a view containing the measurement graph at the corresponding coordinates, and obtaining the target editing view.

The acquired target clip view may refer to the images shown in fig. 3 and 4.

As shown in the figure, the substrate on which the first test contour information is located is a target clip view, and it can be seen that the target clip view includes a white bright area of a measurement graph (a polygonal structure shown in the figure) corresponding to the first test contour information (a quadrilateral structure shown in the figure) and a white bright area of other measurement graphs (areas where two white bright lines are formed), that is, the polygonal structure shown in the figure, and therefore, the target clip view includes only a small amount of other measurement graphs because of being clipped according to a predetermined size. Therefore, the measuring graph can be conveniently and quickly determined, and a foundation is provided for aligning the first test contour information with the corresponding measuring graph.

In order to facilitate the subsequent processing based on the first test contour information, calibration is required according to the corresponding measurement pattern in the target reference image information, so that the integrity and reliability of the first test contour information are ensured.

Therefore, after the first test contour information is obtained, the first test contour information is calibrated, that is, aligned with the edge of the measurement pattern, according to the measurement pattern at the corresponding coordinate in the target reference image information.

In this way, a reliable basis can be provided for the subsequent acquisition of profile information.

In order to accurately align the first test contour information with the edge of the corresponding measurement graph, in an embodiment, the process of overlapping the first test contour information with the edge of the measurement graph at the corresponding coordinate in the target clip view to obtain the first aligned contour information may include:

determining a predetermined movement coordinate range of the target clip view; moving the first test contour information within the preset moving coordinate range, and determining the overlapping rate of the side quantity graph at the corresponding coordinate in the first test contour information and the target clip view; and when the overlapping rate reaches a preset overlapping value, obtaining the first test contour information.

The predetermined moving coordinate range is a predetermined range in which the first test contour information can be moved within a certain range centering on the coordinates of the first test contour information within a predetermined size range.

The predetermined movement coordinate range may be set according to circumstances.

The alignment results thereof may be continued with reference to fig. 4, taking as an example the alignment state of the first test profile information shown in fig. 4.

First, the first test contour information (i.e., the first test contour information just extracted as shown in the drawing) will be extracted, and can be moved in the direction of the upper right corner within a predetermined movement coordinate range. At this time, it can be known that the overlapping ratio of the first test contour information and the measurement pattern is gradually increased, and then the movement is continued along the direction of the upper right corner until the overlapping ratio reaches a sufficient value, that is, a preset overlapping value is reached, for example, the preset overlapping value is 95%, 98%, 99%, 100% (in an ideal state), which indicates that the first test contour information and the measurement pattern completely overlap, and the first alignment contour information is obtained.

Thus, when the contour information is extracted and obtained based on the first alignment contour information later, the reference is accurate and meets the design requirement.

In order to be able to maximize that the finally obtained profile information meets the design requirements, in one embodiment the first alignment profile information may be extracted and aligned again.

Specifically, after the step of obtaining the first alignment profile information, before the step of obtaining the profile information corresponding to the test lithography pattern, the method may further include the following steps:

acquiring test image information containing the first alignment contour information; extracting a target contour intensity signal of the test photoetching pattern according to the intensity signal of the test image information to obtain second test contour information; and fitting the second test contour information with the edge of the measurement graph at the corresponding coordinate to obtain second alignment contour information.

The test image information containing the first alignment contour information is the test image information used for extracting the first test contour information, namely, when the contour information is extracted for the second time, the test image information is carried out on the basis that the contour information is extracted for the first time and is aligned with the edge of the test pattern at the corresponding coordinate.

In this way, the integrity and reliability of the profile information extraction can be further ensured.

The second profile information is extracted based on the intensity signal of the test lithography pattern in the test image information, and reference may be made to fig. 5 and 6, where fig. 5 is a schematic diagram of the test lithography pattern corresponding to the first alignment profile information provided in the embodiment of the present application, and fig. 6 is a schematic diagram of the intensity signal of the test lithography pattern shown in fig. 5.

As shown, the abscissa is the contour coordinate and the ordinate is the intensity signal.

When the intensity signals meeting the threshold value of the target profile intensity signal are extracted, the corresponding profile coordinates can be obtained, and second test profile information is obtained according to the area surrounded by the profile coordinates.

Based on the above, in the CD-SEM image, the gray scale image is mainly used, the white bright area represents the contour information of each test lithography pattern, and the black dark area represents the area of the non-contour information, so that the intensity signal corresponding to the white bright area is higher than the intensity signal corresponding to the black dark area, and the contour information of the test lithography pattern to be obtained can be extracted according to the intensity signal.

In order to ensure that the profile information extracted for the second time is complete based on the second test profile information, the missing or inexpensive profile parts in the second test profile information can be supplemented and adjusted according to the edges of the test pattern at the corresponding coordinates in the target reference image information.

Specifically, in one embodiment, the process of extracting the target profile intensity signal corresponding to the test lithography pattern according to the intensity signal of the test image information to obtain the second test profile information may include:

acquiring test image information containing the first test contour information, and determining an intensity signal of the test image information; determining an intensity signal meeting a target contour intensity signal threshold value in the intensity signals to obtain target contour intensity signals; and extracting contour coordinates corresponding to the target contour intensity signal to obtain corresponding second test contour information.

The target profile intensity signal threshold is an intensity signal corresponding to profile information of a test lithography pattern to be extracted, and specific values can be set according to the profile information of different test lithography patterns, for example, 50%, 75%, 80% and 100%.

The purpose of setting the target contour intensity signal threshold value can be convenient, rapid and accurate to extract the second test contour information on the one hand, and can filter the intensity information of the contour information of other test lithography patterns on the other hand, so that the obtained second test contour information and the first test contour information are both obtained based on the same test lithography pattern, and the accuracy of the extracted contour information is ensured.

For ease of understanding, reference may be made to fig. 7, in which fig. 7 is a schematic diagram of a test pattern obtained correspondingly under the signal intensity shown in fig. 6, and fig. 8 is a schematic diagram of second test profile information of the method for correcting a pattern according to an embodiment of the present application.

As shown in the figure, the test image information obtained from the intensity signal includes a region of contour information corresponding to the intensity signal having a high value and a region of background, i.e., non-contour information, corresponding to the intensity signal having a low value. The larger white bright area is the second test contour information, and it can be seen that a smaller white bright area is arranged at a position far away from the second test contour information at the lower left corner in the figure, and the white bright area is the contour information of other test photoetching patterns and does not accord with the target contour intensity signal threshold value, and is the area needing filtering.

The result of extraction of the profile information after filtering is shown in fig. 8. And filtering out the contour information corresponding to the intensity signal which does not accord with the target contour intensity signal threshold value, wherein the extracted final contour information is the second test contour information which needs to be obtained, and the second test contour information is the same test photoetching pattern corresponding to the first test contour information.

According to fig. 8, it can be seen that the edge of the second test profile information obtained based on the intensity signal is incomplete, so that in order to further improve the integrity and accuracy of the finally obtained profile information, the accuracy of the profile information is optimized, and in one embodiment, the process of fitting the second test profile information to the edge of the measurement pattern at the corresponding coordinates to obtain second aligned profile information may include:

Determining a measurement graph at a corresponding coordinate in a target clipping view of the target reference image information according to the coordinates of the second test contour information to obtain a target measurement graph; acquiring each contour coordinate of the second test contour information and each target contour coordinate of the target measurement graph; determining a first edge average error of the contour coordinates and the target contour coordinates in a first direction; determining a second edge average error of the contour coordinates and the target contour coordinates in a second direction, wherein the second direction is perpendicular to the first direction; obtaining a first moving average value according to each first edge average error, and obtaining a second moving average value according to each second edge average error; and moving the second test contour information in the first direction according to the first moving average value, and moving the second test contour information in the second direction according to the second moving average value so as to fit the second test contour information with the edge of the target measurement graph to obtain the second alignment contour information.

In this step, first, the second test contour information extracted for the second time is overlapped with the test image information (i.e., the target clip view) aligned based on the first extraction. Then, edge errors EPE between the second test contour information and the target measurement patterns (i.e., polygonal structures as shown) are measured in a first direction (i.e., left and right edges of the target clip view) and a second direction (i.e., top and bottom edges of the target clip view) on a plane in which the overlapped target clip views are located, and then corresponding edge average errors (first edge average error and second edge average error) are obtained based on the respective edge errors EPE. Finally, a moving average (a first moving average and a second moving average) of the edge average error in each direction is calculated, and the extracted second test contour information is moved according to the first moving average and the second moving average, so that the second test contour information is horizontally moved in the first direction X and vertically moved in the second direction Y to realize second alignment, namely edge fitting.

Referring to fig. 9 and fig. 10, fig. 9 is a schematic diagram illustrating a state of edge error in the photolithography pattern correction method according to the embodiment of the present application, and fig. 10 is a schematic diagram illustrating a state of edge fitting of the second test profile information shown in fig. 8.

As shown in fig. 9, the solid portion G in the drawing represents each measurement figure in the target clip view, and the solid line box C represents the extracted second test contour information, and since the coordinates of each second test contour information and the coordinates of each measurement figure can be determined from the coordinate relationship, each edge error EPE can be obtained quickly.

As can be seen from the foregoing discussion, the edges of the second test profile information are defined by respective profile coordinates, and two edge errors EPEs are obtained in one moving direction, for example, in the first direction, corresponding edge errors EPEs are obtained in the second direction according to the left edge and the right edge of the second test profile information, corresponding edge errors EPEs are obtained in the second direction according to the top edge and the bottom edge of the second test profile information, in order to be able to improve the accuracy of the second test profile information, the obtained edge errors EPEs are first taken as edge average values (first edge average error and second edge average error), and then corresponding moving average values (first moving average value and second moving average value) are obtained according to the edge average error in each direction, and the corresponding moving average values are moved in the respective directions so that the second test profile information can be aligned with the measurement pattern in the target clip view.

Specifically, the first moving average X _shift and the second moving average Y _shift may be calculated by the following formulas:

Where EPE _right represents the right edge error, EPE _left represents the left edge error, EPE _top represents the edge position error of the top edge, EPE _bottom represents the edge position error of the bottom edge, n represents the number of coordinates (contour coordinates and target contour coordinates), and i represents the current coordinates.

The target contour coordinates and contour coordinates are corresponding and are therefore represented in coordinates.

In the first direction, the left edge and the right edge respectively correspond to a plurality of coordinates, so that the left edge error and the right edge error can be subjected to mean value processing, the top edge error and the bottom edge error can be subjected to mean value processing in the same second direction, then a first edge average error and a second edge average error are obtained, further, the two first edge average errors are averaged to obtain a first moving mean value, the two second edge average errors are averaged to obtain a second moving mean value, and therefore the second test contour information can be smoothly and stably moved to obtain second alignment contour information.

In order to enable the extracted profile information to conform to the profile of a real test lithography pattern, in an implementation manner, when the CD-SEM scanning is used for the test lithography pattern of the mask, the lithography pattern correction method provided by the embodiment of the application obtains the test image information without feature size information and the feature test image information with feature size information at the same time, wherein the test image information without feature size information is the image information for extracting the profile information, and the feature test image information with feature size information is used for performing profile matching on the profile information extracted based on the test image information so as to improve the reliability of the profile information.

Specifically, the target reference image information includes feature size information of each measurement pattern, and after the step of obtaining the second alignment profile information, the method may further include:

Measuring the characteristic dimension of the second alignment contour information to obtain contour characteristic dimension information; determining the characteristic dimension information of the measurement graph at the corresponding coordinate position by utilizing the coordinates of the second alignment contour information; and matching the second alignment contour information by utilizing the contour feature size information and the feature size information.

Specifically, reference may be made to fig. 11 to fig. 13, fig. 11 is a schematic diagram of measurement patterns with feature size information according to the method for correcting a lithographic pattern provided in the embodiment of the present application, fig. 12 is a schematic diagram of feature size information corresponding to one measurement pattern in the measurement patterns shown in fig. 11, and fig. 13 is a schematic diagram of profile feature size information of second alignment profile information shown in fig. 10.

As shown in fig. 12, the bright light rays on both sides of the measurement pattern are corresponding feature size information, and as shown in fig. 13, the range defined by the bright rectangular frame is the outline feature size information of the second alignment outline information.

In this way, feature size information of a measurement pattern that can be used as a reference is obtained by the CD-SEM, and the extracted profile information (second alignment profile information) is matched, thereby further ensuring the reliability of the profile information (second profile information).

For each piece of test image information, corresponding target reference image information is provided, and correspondingly, the test lithography patterns contained in each piece of test image information are provided with corresponding measurement patterns with characteristic size information in the target reference image information.

As shown in fig. 12 and 13, it can be seen that the measurement of the feature size information of the measurement pattern in the extracted second alignment profile information and the measurement of the feature size information of the measurement pattern in the target alignment image information remain consistent, and the reliability of the obtained second alignment profile information is improved.

In order to ensure the matching effect of the profile information, in one embodiment, the matching process of the second alignment profile information using the profile feature size information and the feature size information may include:

Determining the outline characteristic dimension information and each characteristic error of the characteristic dimension information to obtain a characteristic dimension information error mean value; and when the characteristic dimension information error mean value is larger than a preset characteristic dimension information error value, adjusting the outline characteristic dimension information until the characteristic dimension information error mean value meets the preset characteristic dimension information error value, and completing the matching of the second alignment outline information.

In the process of matching the second alignment profile information, a characteristic dimension information error mean value is defined and used for representing errors existing between the second alignment profile information and a corresponding measurement graph serving as a reference, and a corresponding expression formula can be:

ΔCD_difference＝∑(CD_contour-CD_sem)/n

In the above formula, Δcd _difference represents the mean value of the feature size information error, CD _contour represents the outline feature size information, CD _sem represents the feature size information, and n represents the number of feature size information.

When the characteristic dimension information error mean value is larger than the preset characteristic dimension information error value, the fact that the difference between the extracted second alignment contour information and the measurement graph required by design is large is that the second alignment contour information cannot be used for subsequent correction model construction is indicated, and therefore the second alignment contour information needs to be readjusted to ensure the accuracy and the reliability of the second alignment contour information.

In one embodiment, the adjusting the profile feature size information may include:

Since the profile information extraction and alignment have been performed twice at this time, the gap between the second alignment profile information and the corresponding measurement pattern at this time is normally small, so that the adjustment of the feature size information error mean is selected to adjust the second alignment profile information in general, so as to achieve accurate matching.

Of course, when the mean value of the characteristic dimension information error is still larger than the predetermined characteristic dimension information error value after adjustment, the first and second extraction and alignment of the profile information are required to be performed again.

Step S003: and constructing a correction model according to the outline information of the test lithography pattern, and correcting the lithography pattern to be corrected on the mask plate by using the correction model.

To reduce measurement errors in the CD-SEM that exist in obtaining profile feature size information, it is common to average a plurality of profile feature size information from the same test lithography pattern, second alignment profile information, for processing common profile feature size information.

Specifically, after the second alignment profile information is obtained, the method may further include the following steps:

Determining other second alignment contour information in the test image information corresponding to the second alignment contour information; obtaining the distance between the second alignment contour information and each piece of other second alignment contour information, and the distance between the second alignment contour information and the edge of the measurement graph at the corresponding coordinate in the target reference image information, so as to obtain a distance vector; and judging the credibility of the second alignment contour information by using the distance vector to obtain a credible contour, and carrying out contour average on the credible contour to obtain the contour information.

Because the test image information obtained by the CD-SEM scanning is large in noise, the contrast ratio of edge detection is poor, and the edge roughness of each test photoetching pattern in single test image information is uneven (namely, the roughness of the second alignment outline information is uneven).

Contour averaging is a necessary but more complex task. For complex features (two-dimensional features), it is difficult to distinguish between the good and bad parts of the single second alignment profile information (such as corners), refer to fig. 14-18, fig. 14 is a schematic diagram of a test lithography pattern of the two-dimensional features provided by the embodiment of the present application, fig. 15 is a schematic diagram of a state in which the test lithography pattern shown in fig. 14 includes an unreliable profile, fig. 16 is a schematic diagram of profile information extracted from the test lithography pattern shown in fig. 15, fig. 17 is a schematic diagram of averaging the profile information shown in fig. 16, and fig. 18 is a schematic diagram of a result of filtering and profile averaging the unreliable profile information in the lithography pattern correction method provided by the embodiment of the present application.

Fig. 14 shows two-dimensional features included in a test pattern, fig. 15 shows test image information including an unreliable contour, and the contour extraction is performed on the test image information shown in fig. 15 by using the method for correcting a pattern of lithography provided by the present application, so as to obtain contour information including an unreliable contour. The contour information shown by the oval in fig. 16 is the unreliable contour in the unreliable contour map 15.

It can be seen that the profile information indicated by arrow F is the second alignment profile information corresponding to the two-dimensional feature, which is very disadvantageous for the subsequent correction model construction, and if the profile averaging is directly performed on these second alignment profile information, the resulting average profile is unsatisfactory, i.e. as shown in fig. 17.

Therefore, in order to ensure the reliability and accuracy of the final profile information, the second alignment profile information that is not reliable (can not be used for modeling correction) may be filtered out and then profile averaged to obtain reliable profile information, and specifically, reference may be made to fig. 18.

Contour averaging is very sensitive to any part of the contour information that is not trusted. Thus, the distance between the individual average contour information and the distance between the average contour information and the edge of the measurement pattern at the corresponding coordinates in the target reference image information can be further clarified by the distance vector.

The distance vector is used for judging the credibility of the second alignment outline information, and the unreliable part is filtered out. Then, for performing contour averaging on the trusted contours, reference may be made to fig. 19 and 20, where fig. 19 is a schematic process diagram of filtering the untrusted contour information in the photolithography pattern correction method according to the embodiment of the present application, and fig. 20 is a schematic process diagram of performing contour averaging on the trusted contours in the photolithography pattern correction method according to the embodiment of the present application.

The reliability can be preset, the second alignment contour information higher than the reliability is discharged and filtered, and the remaining second alignment contour information is final contour information which meets the requirement of constructing the correction model, so that the reliability of the finally constructed correction model can be ensured.

It can be seen that, according to the method for correcting the lithography pattern provided by the embodiment of the application, by utilizing the target reference image information and the test image information, the profile information containing the two-dimensional characteristic information corresponding to the test lithography pattern is obtained, and the two-dimensional characteristic information can enhance the integrity and reliability of the obtained profile of the test lithography pattern, so that the correction effect of the correction model constructed based on the profile information is ensured, the profile correction precision and accuracy of the correction model are improved, and the precision of correcting the lithography pattern by the correction model is improved.

In order to ensure the correction accuracy of the finally constructed correction model, the profile information may be further processed, and specifically, please refer to fig. 21, fig. 21 is another flow chart of the photolithography graphic correction method according to the embodiment of the present application.

As shown in the figure, the flow may include the steps of:

step S100: target reference image information and test image information are acquired.

Step S101: and obtaining contour information corresponding to the test lithography pattern based on the target reference image information and the test image information, wherein the contour information comprises two-dimensional characteristic information of the test lithography pattern.

The contents of step S100 to step S101 may refer to the contents of step S001 to step S002, and will not be described herein.

Step S102: and editing the contour information to obtain target contour editing information, wherein the target contour editing information comprises independent contour information for correcting the photoetching graph to be corrected.

When the correction model is used for correcting the to-be-corrected photoetching patterns on the mask, the single to-be-corrected photoetching patterns to be corrected are corrected, so that the correction effect of each to-be-corrected photoetching pattern can be improved, each piece of extracted contour information is independently clipped, and independent target contour clipping information is obtained, so that the to-be-corrected photoetching patterns can be corrected in a targeted manner, and the correction effect of the correction model is enhanced.

Target profile clip information reference is made to fig. 22. Fig. 22 is a schematic diagram of target profile clip information in a method for lithographically correcting an embodiment of the present application.

Since there are many pieces of acquired target profile clip information, and different types of target profile clip information have different correction effects when correcting the to-be-corrected photolithography graphic, the weights of the respective target profile clip information may be configured according to the correction importance, i.e., the correction effect, of the respective target profile clip information, and, in detail, please continue to refer to fig. 21.

As shown in the figure, the lithographic pattern correction method may further include:

Step S103: and carrying out corresponding weight configuration on the target contour clipping information to obtain target clipping contour weight information, wherein the target clipping contour weight information is used for representing the correction effect of each piece of target contour clipping information.

By carrying out weight configuration on the target contour clipping information with different correction effects, the target contour clipping information with good correction effects can be determined, and the target contour clipping information with high weight can be preferentially selected when the correction model is constructed, so that the correction effect of the correction model is improved.

When the target contour clipping information with high weight is selected, a manual or semi-automatic mode can be selected, and the target contour clipping information with good correction effect can be obtained.

Configuration weights referring to fig. 23, fig. 23 is a schematic diagram of target clip profile weight information in a photolithography graphic correction method according to an embodiment of the present application.

As shown, the corresponding Weight (Weight) in each target profile clip information represents the importance and effectiveness of each target profile clip information in correcting the lithography to be corrected.

Since the correction model can be constructed in order to construct a high-quality correction model, it can be constructed based on the information obtained in the above steps, please continue to refer to fig. 21.

As shown in the figure, i.e., step S003 may include:

Step S104: and constructing the correction model according to the contour information of the test photoetching graph, the target contour clipping information, the target clipping contour weight information and the measurement graph on the target layer.

In this way, the correction model is constructed based on the profile information including the two-dimensional feature information, the target profile clipping information obtained by clipping the profile information, the target clipping profile weight information corresponding to each target profile clipping information, and the target reference image information on the target layer for calibrating the profile information, the correction capability of the correction model is enhanced, and the correction reliability and accuracy of the correction model are improved.

After the correction model is built, in order to ensure that the correction effect of the correction model is satisfactory, the correction effect of the correction model may be verified after the correction model is obtained, specifically, please continue to refer to fig. 21.

As shown in fig. 2, the process may further include the steps of:

Step S105: the test image information is acquired including feature test image information with feature size information.

Based on the foregoing, it can be appreciated that the layout file converted from the CD-SEM measurement data may include feature size information, and thus the correction model may be further calibrated based on the actually measured feature size information.

And step S106, verifying the correction model by using the characteristic test image information, determining whether the correction effect reaches the correction expected value, if so, executing step S107, and if not, executing step S108.

When the correction effect reaches the correction expected value, it indicates that the correction model is successfully constructed and can be normally used, i.e. step S107.

Step S107: and obtaining the constructed correction model.

When the correction effect of the correction model does not reach the correction expected value, it is indicated that the constructed correction model cannot be used normally, and further, it is indicated that the used test image information is unsuitable, and at this time, the test image information needs to be updated, that is, step S108.

Step S108: and updating the test image information to obtain new test image information.

After updating the test image information, the contour extraction and calibration are continuously performed according to the target reference image information, so as to obtain contour information capable of constructing a high-quality correction model, namely, the step S100 is continuously performed.

In this way, by means of the multi-type construction model data (contour information, target contour clipping information, target clipping contour weight information, and target reference image information on a target layer), the correction effect of the constructed correction model and the reliability of the correction result are enhanced, the correction effect of the correction model is further verified, the correction effect of the correction model is ensured to be stable and meet the correction requirement, and therefore the correction accuracy of the finally obtained and constructed correction model is ensured.

In order to embody the correction effect of the photolithography pattern correction method provided by the embodiment of the present application, reference may be made to fig. 24 and 25, fig. 24 is a schematic diagram of the construction and calibration of a correction model in the photolithography pattern correction method provided by the embodiment of the present application, and fig. 25 is a schematic diagram of the correction effect of the correction model constructed by the conventional method.

In the figure, C1 is the correction effect of the correction model constructed by the conventional method, and C2 is the correction effect of the correction model constructed by the photolithography pattern correction method provided by the embodiment of the application. It can be seen that, in the photolithography pattern correction method provided by the embodiment of the present application, the correction effect (model error) C2 of the correction model constructed based on the profile is better than the correction effect (model error) C1 of the correction model constructed by the conventional method.

An embodiment of the present application further provides a lithographic apparatus, and fig. 26 is a schematic frame diagram of the lithographic apparatus according to the embodiment of the present application.

As shown, the apparatus may include:

The image information obtaining module 260 is adapted to obtain target reference image information and test image information, where the target reference image information is used to indicate a measurement pattern of a reference lithography image and corresponding coordinates on a target layer of a mask, the test image information is test image information of a test lithography pattern obtained based on the mask, and the coordinates of the test lithography pattern in the test image information have a mapping relationship with the coordinates of the measurement pattern;

the profile information acquisition module 261 is used for acquiring profile information corresponding to the test lithography pattern based on the target reference image information and the test image information, wherein the profile information comprises two-dimensional characteristic information of the test lithography pattern;

And the correction module 262 is adapted to construct a correction model according to the outline information of the test lithography pattern, and correct the lithography pattern to be corrected on the mask plate by using the correction model.

It can be seen that, according to the lithographic pattern correction device provided by the embodiment of the application, by utilizing the target reference image information and the test image information, the outline information containing the two-dimensional characteristic information corresponding to the test lithographic pattern is obtained, and the two-dimensional characteristic information can enhance the outline integrity and reliability of the obtained test lithographic pattern, so that the correction effect of the correction model constructed based on the outline information is ensured, the outline correction precision and accuracy of the correction model are improved, and the precision of correcting the lithographic pattern by the OPC model is improved.

Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the application, and the scope of the application should be assessed accordingly to that of the appended claims.

Claims

1. A method of lithographic patterning comprising:

2. The method of lithographic pattern correction according to claim 1, wherein said obtaining profile information corresponding to said test lithographic pattern based on said target reference image information and said test image information comprises:

3. The method of lithographic pattern correction according to claim 2, wherein said overlapping the first test profile information with the pattern edge of the target reference image information at the corresponding coordinates to obtain first alignment profile information, comprises:

4. A method for correcting a lithography pattern as claimed in claim 3, wherein said determining, based on the coordinates of the test lithography pattern, a clip view of the measurement pattern at the corresponding coordinates contained in the target reference image information to obtain a target clip view comprises:

acquiring coordinates of the test lithography pattern;

5. A method of lithographically correcting according to claim 3, wherein the overlapping the first test contour information with edges of the measurement pattern at corresponding coordinates in the target clip view to obtain the first alignment contour information includes:

Determining a predetermined movement coordinate range of the target clip view;

6. The method of lithographic pattern correction according to claim 2, wherein after said step of obtaining first alignment profile information, before said step of obtaining profile information corresponding to said test lithographic pattern, further comprising:

7. The method for correcting a lithography pattern as claimed in claim 6, wherein extracting a target profile intensity signal corresponding to the test lithography pattern based on the intensity signal of the test image information to obtain second test profile information comprises:

8. The method of claim 6, wherein fitting the second test profile information to the edges of the measurement pattern at the corresponding coordinates to obtain second alignment profile information comprises:

9. A method of lithographically correcting according to claim 3 wherein the target reference image information includes feature size information for each measurement pattern, and wherein the step of obtaining second alignment profile information further comprises, after the step of obtaining second alignment profile information:

measuring the characteristic dimension of the second alignment contour information to obtain contour characteristic dimension information; determining the characteristic dimension information of the measurement graph at the corresponding coordinate position by utilizing the coordinates of the second alignment contour information;

10. The lithographic pattern correction method according to claim 9, wherein said matching of said second alignment profile information using said profile feature size information and said feature size information comprises:

11. The lithographic pattern correction method according to claim 10, wherein said adjusting said profile feature size information comprises:

12. The lithographic pattern correction method according to claim 6, wherein after said step of obtaining second alignment profile information, further comprising:

13. The lithographic pattern correction method according to any one of claims 1 to 12, wherein before said step of obtaining profile information corresponding to said test lithographic pattern based on said target reference image information and said test image information, further comprising:

14. The lithographic pattern correction method according to any one of claims 1 to 12, further comprising, after said step of obtaining profile information corresponding to said test lithographic pattern based on said target reference image information and said test image information:

15. The lithographic pattern correction method of claim 14, wherein said step of clipping said profile information to obtain target profile clipping information further comprises, after said step of:

16. The lithographic pattern correction method according to claim 15, wherein said constructing a correction model from profile information of said test lithographic pattern comprises:

17. The lithographic pattern correction method according to claim 16, wherein said test image information includes feature test image information with feature size information, and said step of constructing said correction model from said test lithographic pattern profile information, said target profile clip information, said target clip profile weight information, and target reference image information on said target layer further comprises, after said step of:

18. The lithographic pattern correction method according to any one of claims 1 to 12, wherein said acquiring target reference image information and test image information comprises:

determining a target layer of the mask;

19. The method of claim 18, wherein performing a survey scan of different areas of the reticle containing the test pattern to obtain the test image information comprises:

20. A lithographic apparatus, comprising:

21. A lithographic patterning device according to claim 20, comprising a lithographic patterning device.