Curve mask pattern inspection method and related product

Abstract

The invention provides an inspection method of a curve mask pattern and a related product. The inspection method of the curve mask pattern comprises the following steps: respectively acquiring an original pattern and an optimized pattern of the mask pattern, wherein the optimized pattern is obtained by performing curve optical proximity correction on the original pattern; under the condition that the original graph has the symmetric structure, judging whether the symmetric structure is still kept symmetric in the optimized graph; and obtaining an inspection result of the optimized graph according to a judgment result of the symmetry of the symmetric structure. According to the testing method, effective testing of the symmetry of the curve layout after curve optical proximity correction is achieved, the curve mask pattern with asymmetric deformation can be effectively prevented from entering a chip manufacturing link, and the manufacturing yield of chips is improved.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit technology, and in particular to a method for inspecting curve mask layouts, a computer-readable storage medium, a computer program product, and a computer device. Background Technology

[0002] With the continuous development of integrated circuit technology, curve mask technology has become a key technology for breaking through the resolution bottleneck. Traditionally, mask layouts based on Manhattan structures (Manhattan Mask) are being replaced by curve layouts based on spline curves to meet the need for accurate representation of complex device contours at nodes of 5nm and below.

[0003] While curve masking technology improves node resolution and design flexibility, it introduces many new challenges, especially during the optimization stage of Curvilinear Optical Proximity Correction (Curvilinear OPC). Specifically, when existing Curvilinear OPC algorithms perform local optimization on control points of the curve in a pattern, gradient differences in physical parameters such as proximity effects and etching load can lead to nonlinear displacement of the control points. This results in heterogeneous displacement of control points at symmetrical positions, causing asymmetric deformation of the curve and disrupting the geometric symmetry of the pattern. Even if the amount of such asymmetric deformation is small (typically less than 1 nm), it can still cause deeper problems such as device current imbalance and timing offset, ultimately leading to a significant yield loss. Summary of the Invention

[0004] One object of the present invention is to provide a method for inspecting curve mask layouts, a computer-readable storage medium, a computer program product, and a computer device to perform symmetry inspection on curve layouts after optical proximity correction, and to prevent asymmetric deformation caused by optical proximity correction from affecting chip manufacturing yield.

[0005] A further objective of this invention is to improve the accuracy and efficiency of symmetry testing of curve layouts.

[0006] Specifically, according to one aspect of the present invention, the present invention provides a method for inspecting a curve mask layout, comprising: The original and optimized images of the mask pattern are obtained separately, wherein the optimized image is obtained by performing curve optical proximity correction on the original image; If the original graphic has a symmetrical structure, determine whether the symmetrical structure remains symmetrical in the optimized graphic; wherein, the symmetrical structure includes two parts that are symmetrical about one axis of symmetry of the original graphic; The verification result of the optimized graphic is obtained based on the judgment result of the symmetry of the symmetrical structure.

[0007] Optionally, determining whether the symmetrical structure remains symmetrical in the optimized graphic when the original graphic has a symmetrical structure includes: Obtain multiple control points of the original graphic, and the original graphic coordinates of each control point; the multiple control points determine the shape of the original graphic; Construct multiple control point groups, each control point group including multiple control points symmetrical about a horizontal or vertical axis of symmetry relative to the original graphic; Obtain the optimized graphic coordinates of each control point in the optimized graphic; Based on the optimized graphic coordinates and the original graphic coordinates of each control point, determine whether each control point in each control point group still maintains symmetry in the optimized graphic. If each control point in each control point group remains symmetrical in the optimized graph, then the symmetrical structure is determined to remain symmetrical in the optimized graph.

[0008] Optionally, constructing multiple control point groups includes: Based on the relative positional relationship between each control point and other control points within a preset range around it, an identifier number is generated for each control point, so that a pair of control points that are symmetrical about any horizontal or vertical axis of symmetry of the original graphic use the same identifier number. Each of the control points using the same identifier number is considered as a group of control points.

[0009] Optionally, determining the identifier of each control point based on its relative position to other control points within a preset range, so that a pair of control points symmetrical to any horizontal or vertical axis of symmetry of the original graphic uses the same identifier, includes: Traverse all the control points and obtain the surrounding preset range centered on the traversed control point; Using the surrounding preset range as the calculation window, and using all the control points within the calculation window as each pixel point, the image hash value of the calculation window is calculated; The image hash value of the calculation window is used as the identifier of the control point being traversed.

[0010] Optionally, after the step of constructing multiple control point groups, the method further includes: Determine whether the number of control points in each control point group is even. If so, then it is determined that the original graphic has the symmetrical structure.

[0011] Optionally, determining whether each control point in each control point group remains symmetrical in the optimized graphic based on the optimized graphic coordinates and the original graphic coordinates of each control point includes: Calculate the displacement vector of each control point based on the optimized graphic coordinates and the original graphic coordinates of each control point; Traverse all the control point groups and determine whether the magnitudes of the displacement vectors of all the control points in the traversed control point groups are equal; If they are all equal, then calculate the sum of the X-axis component vectors and the sum of the Y-axis component vectors of the displacement vectors of all the control points in the traversed control point group. Based on the calculated sum of the X-axis component vectors and the sum of the Y-axis component vectors, it is determined that each control point in the traversed control point group remains symmetrical in the optimized graph.

[0012] Optionally, the original graphic is a Manhattan structure graphic.

[0013] Optionally, the original graphic is a graphic obtained by rounding the corners of the Manhattan structure graphic.

[0014] Optionally, the original graphic is a polygon composed of curves.

[0015] According to another aspect of the present invention, a computer-readable storage medium is also provided, on which a computer program is stored, wherein the computer program, when executed by a processor, implements the steps of the curve mask layout inspection method described above.

[0016] According to another aspect of the present invention, a computer program product is also provided, comprising a computer program that, when executed by a processor, implements the steps of the method for verifying the curve mask layout described above.

[0017] According to another aspect of the present invention, a computer device is also provided, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the curve mask pattern inspection method described above.

[0018] The method for inspecting curve mask layouts of the present invention identifies symmetrical structures present in the original pattern and determines whether these symmetrical structures remain symmetrical in the optimized pattern. Based on the symmetry results of the symmetrical structures in the optimized pattern, the mask defect inspection results are obtained. This method enables the inspection of the symmetry of curve layouts after optical proximity correction, effectively preventing curve mask layouts with asymmetrical deformations from entering the chip manufacturing process and improving the chip manufacturing yield.

[0019] Furthermore, the curve mask layout verification method of the present invention improves the efficiency of calculating the identification number of each control point in the original graphic by using the image hash value as the identification number of the control point, ensuring that control points with different relative positional relationships use different identification numbers, and effectively preventing control points that do not have a symmetrical relationship from being placed in the same control point group.

[0020] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0021] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings: Figure 1 This is a flowchart illustrating a method for inspecting a curve mask layout according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the original pattern in the mask layout of an inspection method according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the original pattern in the mask layout of the inspection method according to another embodiment of the present invention; Figure 4 This is a schematic diagram of the original pattern in the mask layout of the inspection method according to another embodiment of the present invention; Figure 5 This is a flowchart illustrating the process of determining whether a symmetrical structure remains symmetrical in an optimized graphic according to an embodiment of the present invention. Figure 6 Yes Figure 4 A schematic diagram showing the optimized image obtained after curve optical proximity correction of the original image; Figure 7 This is a schematic flowchart of a test method for obtaining a control point set according to an embodiment of the present invention; Figure 8 This is a flowchart illustrating the process of determining whether an original graphic has a symmetrical structure according to an embodiment of the present invention. Figure 9 This is a flowchart illustrating the calculation of an identifier number using an inspection method according to an embodiment of the present invention; Figure 10 This is a flowchart illustrating the process of determining whether a symmetrical structure remains symmetrical in an optimized graphic based on displacement vectors according to an embodiment of the present invention. Figure 11 This is a schematic flowchart of an inspection method according to another embodiment of the present invention; Figure 12 This is a schematic diagram of a computer program product according to an embodiment of the present invention; Figure 13 This is a schematic diagram of a computer-readable storage medium according to an embodiment of the present invention; and Figure 14 This is a schematic diagram of a computer device according to an embodiment of the present invention. Detailed Implementation

[0022] The purpose of the curve mask layout inspection method in this embodiment is to prevent asymmetric deformation caused by curve optical proximity correction from affecting chip manufacturing yield.

[0023] Figure 1 This is a flowchart illustrating a method for inspecting a curve mask layout according to an embodiment of the present invention. The method generally includes: S100, acquire the original and optimized images of the mask pattern respectively. The optimized image is obtained from the original image after curve optical proximity correction. S200, if the original graphic has a symmetrical structure, determine whether the symmetrical structure is still symmetrical in the optimized graphic; wherein, the symmetrical structure includes two parts that are symmetrical about one axis of symmetry of the original graphic; S300: Based on the judgment result of the symmetry of the symmetrical structure, the test result of the optimized graphic is obtained.

[0024] In this embodiment, the original graphic of the mask pattern can be a geometric polygon. The original graphic can be a Manhattan structure graphic (such as...). Figure 2-3 As shown), a Manhattan structure graphic is a polygon composed of multiple horizontal and vertical line segments, and it typically has a rectangular bounding box. The original graphic can also be a graphic obtained by rounding the corners of a Manhattan structure graphic using a preset script (such as...). Figure 4As shown in the diagram, this involves converting some or all right angles in the Manhattan structure graphic into rounded corners of a preset type. The original graphic can also be a polygon composed of curves, such as multiple spline curves connected end to end. The spline curves constituting the original graphic can be Bézier curves, B-spline curves, etc., and the shape of each spline curve segment can be determined by several control points. In particular, the original graphic can also be a polygon composed of curves obtained after one or more Curvilinear Optical Proximity Correction (Curvilinear OPC) operations, which is then used for further Curvilinear Optical Proximity Correction.

[0025] Curve optical proximity correction is the process of using spline curves to perform optical proximity correction on the original pattern, resulting in an optimized pattern composed of spline curves. The spline curves constituting the optimized pattern can also be Bézier curves, B-spline curves, etc., and the shape of each spline curve segment can be determined by several control points. Curve optical proximity correction can be used to optimize a Manhattan mask into a curvilinear mask, or to optimize an existing curvilinear mask to obtain a more accurate mask pattern.

[0026] Compared to Manhattan layout, curve layout can greatly improve the flexibility of layout design and meet the need for accurate expression of complex device contours. In particular, for process nodes at 5nm and below, curve layout technology has become a key path to break through the resolution bottleneck.

[0027] However, the inventors discovered that while curved optical proximity correction improves lithography resolution, its design flexibility can easily lead to nonlinear displacement of control points, thereby disrupting the geometric symmetry of the layout. Even if the amount of such asymmetric deformation is small (typically less than 1 nm), it can still cause deeper problems such as device current imbalance and timing offset, ultimately resulting in a significant yield loss. Existing mask defect inspection methods are all designed for the rectangular bounding box of the Manhattan layout, which cannot effectively capture the local curvature characteristics of the curve and lacks sensitivity to gradual symmetry deviations. Currently, no mask defect inspection method has been proposed specifically for the symmetry of curved layouts.

[0028] In this embodiment, after obtaining the original and optimized patterns of the mask layout, it can be first determined whether the original pattern contains a symmetrical structure. For example, it can be determined whether the original pattern itself contains a horizontal axis of symmetry and / or a vertical axis of symmetry, thereby determining whether the original pattern contains a symmetrical structure. The original pattern may only contain a horizontal axis of symmetry (e.g., ...). Figure 3 (As shown). It can also exist with only a vertical axis of symmetry (such as...). Figure 2 As shown). It is also possible for both a horizontal axis of symmetry and a vertical axis of symmetry to exist simultaneously (e.g., Figure 4 (As shown).

[0029] When the original graph does not have a symmetrical structure, it is generally not necessary to consider the symmetry check of the optimized graph. When the original graph has a symmetrical structure, it is necessary to determine whether the symmetrical structure is still maintained in the optimized graph.

[0030] For example, a coordinate offset method can be used to determine whether the symmetrical structures of the original graphic remain symmetrical in the optimized graphic. Specifically, the coordinates of each control point pair of the lines of each symmetrical structure in the original graphic (the shape of a straight line segment can also be determined by a set of control points, each control point pair consisting of two control points symmetrical about the axis of symmetry) can be determined. Then, the new coordinates of each control point pair in the optimized graphic are determined, and then it is determined whether the offset between the new and old coordinates of each control point pair is symmetrical about its axis of symmetry. If both are symmetrical, it indicates that the symmetrical structure of the original graphic remains symmetrical in the optimized graphic. If not, it indicates that the symmetrical structure of the original graphic does not remain symmetrical in the optimized graphic.

[0031] For example, a mirroring method can also be used to determine whether the symmetrical structures of the original pattern remain symmetrical in the optimized pattern. Specifically, one or two axes of symmetry corresponding to each symmetrical structure in the original pattern can be determined, and then the position of the axis of symmetry in the optimized pattern can be determined. Then, half of the pattern on one side of the axis of symmetry in the optimized pattern is mirrored to the other side. Finally, it is determined whether the mirrored half completely covers the half of the pattern in the optimized pattern. If it completely covers the other half, it indicates that the symmetrical structure of the original pattern remains symmetrical in the optimized pattern. If it does not completely cover the other half, it indicates that the symmetrical structure of the original pattern does not remain symmetrical in the optimized pattern, which may cause deeper problems such as device current imbalance and timing offset, ultimately resulting in a significant yield loss. Of course, in the case of incomplete coverage, the coverage rate can be further calculated to determine whether the coverage rate meets the preset requirements. If it does not meet the requirements, it indicates that the symmetrical structure of the original pattern does not remain symmetrical in the optimized pattern.

[0032] After determining whether the symmetrical structure remains symmetrical in the optimized pattern, the symmetry result can be used to determine whether the optimized pattern passes the mask defect inspection. In some preferred embodiments, for optimized patterns that fail the mask defect inspection, the positions of the symmetrical structures that do not maintain symmetry can be noted in the mask defect inspection results, so as to facilitate targeted modification and optimization of the optimized pattern and improve optimization efficiency.

[0033] The method for inspecting curve mask layouts of the present invention identifies symmetrical structures present in the original pattern and determines whether these symmetrical structures remain symmetrical in the optimized pattern. Based on the symmetry results of the symmetrical structures in the optimized pattern, the mask defect inspection results are obtained. This method effectively inspects the symmetry of curve layouts after optical proximity correction, effectively preventing curve mask layouts with asymmetrical deformations from entering the chip manufacturing process and improving chip manufacturing yield.

[0034] In some embodiments of the testing method of the present invention, such as Figure 5 As shown, when the original graphic has a symmetrical structure, determining whether the symmetrical structure remains symmetrical in the optimized graphic includes: S211, Obtain multiple control points of the original graphic, as well as the original graphic coordinates of each control point; the multiple control points determine the shape of the original graphic; S213, construct multiple control point groups, each control point group including multiple control points symmetrical to a horizontal or vertical axis of symmetry relative to the original figure; S215, Obtain the coordinates of each control point in the optimized graph; S217, Based on the optimized graphic coordinates and original graphic coordinates of each control point, determine whether each control point in each control point group still maintains symmetry in the optimized graphic; S219, if each control point in each control point group remains symmetrical in the optimized graph, then it is determined that the symmetrical structure remains symmetrical in the optimized graph.

[0035] In this embodiment, the mask pattern before curve optical proximity correction has an original graphic coordinate system, and the mask pattern after curve optical proximity correction has an optimized graphic coordinate system. The original graphic coordinate system and the optimized graphic coordinate system can usually use the same coordinate system.

[0036] In this embodiment, the original graphic coordinates of all control points in the original graphic are first determined, or only the original graphic coordinates of the control points used to form the symmetrical structure in the original graphic can be determined. Next, for an original graphic that only has a horizontal axis of symmetry, a pair of control points symmetrical to that axis of symmetry are grouped into a control point group, i.e., each control point group may include 2 control points (e.g., ...). Figure 3 (Two control points labeled h1). For the original figure that only has a vertical axis of symmetry, the pair of control points symmetrical about that axis of symmetry are also grouped into a control point group, that is, each control point group may include two control points (e.g., Figure 2 (Two control points labeled h1). For an original figure that has both a horizontal axis of symmetry and a vertical axis of symmetry, each group of control points may include two (e.g., ...). Figure 4 Two control points with the identifier h3), and four (e.g., Figure 4(The four control points with the Chinese identifier h1) and an even number of control points.

[0037] The following explanation uses the original image as an example, showing the Manhattan structure image after rounding off its right angles. Please refer to [link / reference]. Figure 4 and Figure 6 As shown, Figure 4 The diagram illustrates an original graphic with a symmetrical structure. This graphic is the result of rounding the corners of a rectangle. h1-h5 are the identification numbers of the control points, and control points with the same identification number belong to the same control point group. Figure 6 It indicated that Figure 4 The optimized image is obtained after curve optical proximity correction is performed on the original image. To distinguish between the original control points and the new control points, Figure 6 In this context, 'k' replaces 'h' in the original control point's identifier. It's important to understand that in practice, the original control point and the new control point can use the same identifier.

[0038] After identifying multiple control point groups and the original graphic coordinates of each control point within each group, the optimized graphic coordinates of each control point in each control point group can be found in the optimized graphic. Next, the original and optimized graphic coordinates of the control points can be used to determine whether any two control points in each control point group remain symmetrical in the optimized graphic. For example, symmetry axes corresponding to the axes of symmetry in the original graphic can be constructed in the optimized graphic to determine whether the optimized graphic coordinates of corresponding two control points in each control point group are symmetrical relative to the corresponding axes of symmetry. For example, the displacement vector of each control point can be calculated, and the symmetry of corresponding two control points in the same control point group can be used to determine whether they remain symmetrical. If both corresponding control points in each control point group remain symmetrical in the optimized graphic, then the optimized graphic is determined to remain symmetrical.

[0039] In some embodiments of the testing method of the present invention, such as Figure 7 As shown, multiple control point groups are constructed, including: S221, Based on the relative positional relationship between each control point and other control points within a preset range around it, generate an identifier for each control point, so that a pair of control points symmetrical to any horizontal or vertical axis of symmetry of the original graphic use the same identifier. S223, control points using the same identifier number are grouped as a control point group.

[0040] The surrounding preset range can be a square frame, a circular frame, etc., and is not required here. When the surrounding preset range can be a square frame, the side length of the frame can be determined according to the range of optical imaging influence to ensure that a pair of symmetrical control points have the same relative positional relationship with each other control point within the surrounding preset range. For example, the side length of the frame can be proportional to the wavelength of the lithographic light wave, proportional to the pupil grid of the lithographic imaging system, and inversely proportional to the numerical aperture (NA) of the lithographic imaging system. For symmetrical structures in the original pattern, the relative positions of two symmetrical control points and each other control point within the surrounding preset range must be the same. In this embodiment, an image recognition method can be used to generate the same identifier for two or more control points with the same image recognition result.

[0041] Control points within the same control point group share the same identifier, allowing for direct analysis and processing of control points with the same identifier. This facilitates subsequent assessment of whether corresponding control points within the group maintain symmetry in the optimized graphic. Especially when the mask layout contains a massive number of original / optimized graphics, this significantly reduces the number of identifiers, substantially decreases runtime memory usage, and improves processing efficiency.

[0042] In some embodiments of the testing method of the present invention, such as Figure 8 As shown, after the step of constructing multiple control point groups, the following steps are also included: S231, Determine whether the number of control points in each control point group is even; S233, if so, then the original figure is determined to have a symmetrical structure.

[0043] In this embodiment, after generating an identifier for each control point based on its relative position to other control points within a preset range, and grouping control points with the same identifier into a control point group, it is further determined whether the number of control points in each control point group is even. Specifically, each control point group can be traversed, and the number of control points in each traversed control point group can be calculated to see if it is even. This allows for two purposes: firstly, determining whether the original graphic has a symmetrical structure, and if so, verifying whether the symmetrical structure remains symmetrical in the optimized graphic; secondly, if a control point group contains an odd number greater than or equal to 3, it indicates an error in the program generating the identifiers for that group of control points, requiring a correction.

[0044] In some embodiments of the testing method of the present invention, such as Figure 9 As shown, based on the relative positional relationship between each control point and other control points within a preset range around it, an identification number is determined for each control point, so that a pair of control points symmetrical to any horizontal or vertical axis of symmetry of the original graphic uses the same identification number, including: S241, Traverse all control points and obtain the preset range around the traversed control point as the center; S243, using the surrounding preset range as the calculation window, and using all control points within the calculation window as each pixel point, calculate the image hash value of the calculation window; S245, use the image hash value of the calculation window as the identifier of the control point being traversed.

[0045] In this embodiment, an image hashing algorithm is used to calculate the identifier of each control point. The image hashing algorithm can quickly identify the relative positional relationships of all control points within the calculation window and calculate a unique hash value for each relative positional relationship. On the one hand, it can efficiently calculate the hash value of each control point in the original graphic, ensuring that mutually symmetrical control points in a symmetrical structure have the same hash value. On the other hand, it ensures that control points with different relative positional relationships use different hash values, preventing control points that are not mutually symmetrical from being placed in the same control point group. In particular, the image hashing algorithm is especially suitable for cases where the original graphic is a polygon composed of curves. The image hashing algorithm can accurately calculate the relative positional relationships of control points of multiple curve segments within the calculation window, determine control points with the same relative positional relationship, and thus accurately determine the symmetrical structure existing in the original graphic.

[0046] In some embodiments of the testing method of the present invention, such as Figure 10 As shown, based on the optimized and original graphic coordinates of each control point, it is determined whether each control point in each control point group still maintains symmetry in the optimized graphic, including: S271, Calculate the displacement vector of each control point based on the optimized and original graphic coordinates of each control point; S273, traverse all control point groups and determine whether the magnitudes of the displacement vectors of all control points in the traversed control point groups are equal; S275, if all are equal, then calculate the sum of the X-axis and Y-axis components of the displacement vectors of all control points in the traversed control point group; S277. Based on the calculated sum of X-axis and Y-axis component vectors, determine whether each control point in the traversed control point group remains symmetrical in the optimized graph.

[0047] In this embodiment, by calculating the magnitude of the displacement vector of each control point in the same control point group, it can be determined whether the displacement distance of each control point in the same control point group is the same.

[0048] If the magnitudes of the displacement vectors of all control points within the same control point group are the same, then the direction of the displacement vectors needs to be further determined. Specifically, first, the sum of the X-axis and Y-axis components of the displacement vectors of all control points within the same control point group is calculated. Next, based on the control point group, it can be determined whether each control point in the traversed control point group still maintains symmetry in the optimized graph. Specifically, when there are 4 control points in the control point group, it indicates that the original graph has both a horizontal and a vertical axis of symmetry. If the sum of the X-axis and Y-axis components of the displacement vectors of these 4 control points is 0, then it can be determined that each control point still maintains symmetry in the optimized graph. When there are 2 control points in the control point group, it indicates that the original graph has only a horizontal axis of symmetry or only a vertical axis of symmetry. When only a horizontal axis of symmetry exists, if the sum of the Y-axis components of the displacement vectors of these 2 control points is 0, and the sum of the X-axis components is not 0, then it can be determined that each control point still maintains symmetry in the optimized graph. When only a vertical axis of symmetry exists, if the sum of the X-axis component vectors of the displacement vectors of the two control points is 0 and the sum of the Y-axis component vectors is not 0, then it can be determined that each control point remains symmetrical in the optimized graph.

[0049] In some embodiments of the method for inspecting the curve mask layout of the present invention, such as Figure 11 As shown, the testing methods include: S411, obtain the original coordinates of each control point of each graphic in the mask pattern before curve optical proximity correction, and the image hash value of the preset range around each control point, and use the image hash value as the identifier of each control point; S413, obtain the new coordinates of each control point in each pattern of the mask pattern after curve optical proximity correction, and obtain the displacement vector of each control point; S415, Construct an analysis framework. The analysis framework is used to analyze and process the data obtained in steps S411 and S413. S417, using the analysis framework, determines whether each pattern in the mask layout before curve optical proximity correction has a symmetrical structure; S419 uses an analytical framework to determine whether each symmetrical structure remains symmetrical after curve optical proximity correction.

[0050] In step S417, the presence of symmetrical structures in the mask pattern before curve optical proximity correction is determined by checking whether the number of control points with the same identifier is even. In step S419, the magnitude, sum of X-axis components, and sum of Y-axis components of the displacement vectors of control points with the same identifier are analyzed to determine whether the symmetrical structures remain symmetrical after curve optical proximity correction.

[0051] The flowchart provided in this embodiment is not intended to indicate that the operations of the method will be performed in any particular order, or that all operations of the method are included in every case. Furthermore, the method may include additional operations. Within the scope of the technical concept provided by the method in this embodiment, additional variations can be made to the above method.

[0052] It should be understood that in some embodiments, the components may be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods may be implemented using software or firmware stored in memory and executed by a suitable instruction execution system.

[0053] This invention also provides a computer program product 10, a computer-readable storage medium 20, and a computer device 30. Figure 12 This is a schematic diagram of a computer program product 10 according to an embodiment of the present invention. Figure 13 This is a schematic diagram of a computer-readable storage medium 20 according to an embodiment of the present invention. Figure 14 This is a schematic diagram of a computer device 30 according to an embodiment of the present invention. The computer program product 10 includes a computer program 11, which, when executed by the processor 32, implements the steps of the curve mask layout verification method described above. A computer-readable storage medium 20 stores the computer program 11 thereon, which, when executed by the processor 32, implements the steps of the curve mask layout verification method described above. The computer device 30 may include a memory 31, a processor 32, and the computer program 11 stored in the memory 31 and running on the processor 32.

[0054] The computer program 11 used to perform the operations of this invention may be assembly instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, integrated circuit configuration data, or source code or object code written in any combination of one or more programming languages ​​and procedural programming languages. The computer program 11 may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network, including a Local Area Network (LAN) or Wide Area Network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, to perform aspects of this invention, electronic circuits, including, for example, programmable logic circuits, Field-Programmable Gate Arrays (FPGAs), or Programmable Logic Arrays (PLAs), may execute computer-readable program instructions to personalize the electronic circuits by utilizing state information from computer-readable program instructions.

[0055] For the purposes of this embodiment, computer program product 10 is a related product that includes computer program 11.

[0056] For the purposes of this embodiment, the computer-readable storage medium 20 is a tangible device capable of holding and storing a computer program 11. It can be any device capable of containing, storing, communicating, propagating, or transmitting the computer program 11 for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable storage medium 20 include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable optical disc read-only memory (CD-ROM), digital versatile disc (DVD), memory stick, floppy disk, mechanical encoding device, and any suitable combination thereof.

[0057] Computer device 30 can be, for example, a server, desktop computer, laptop computer, tablet computer, or smartphone. In some examples, computer device 30 can be a cloud computing node. Computer device 30 can be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, program modules can include routines, programs, object programs, components, logic, data structures, etc., that perform specific tasks or implement specific abstract data types. Computer device 30 can be implemented in a distributed cloud computing environment where tasks are performed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules can reside on local or remote computing system storage media, including storage devices.

[0058] Computer device 30 may include a processor 32 adapted to execute stored instructions and a memory 31 that provides temporary storage space for the operation of said instructions during operation. The processor 32 may be a single-core processor, a multi-core processor, a computing cluster, or any other configuration. The memory 31 may include random access memory (RAM), read-only memory, flash memory, or any other suitable storage system.

[0059] Computer device 30 may also include a network adapter / interface and an input / output (I / O) interface. The I / O interface allows external devices that can be connected to the computer device to input and output data. The network adapter / interface provides communication between the computer device and a network, typically represented as a communication network.

[0060] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A method for inspecting a curve mask layout, characterized in that, include: The original and optimized images of the mask pattern are obtained separately, wherein the optimized image is obtained by performing curve optical proximity correction on the original image; If the original graphic has a symmetrical structure, determine whether the symmetrical structure remains symmetrical in the optimized graphic; wherein, the symmetrical structure includes two parts that are symmetrical about one axis of symmetry of the original graphic; The verification result of the optimized graphic is obtained based on the judgment result of the symmetry of the symmetrical structure.

2. The testing method according to claim 1, characterized in that, The step of determining whether the symmetrical structure remains symmetrical in the optimized graphic when the original graphic has a symmetrical structure includes: Obtain multiple control points of the original graphic, and the original graphic coordinates of each control point; the multiple control points determine the shape of the original graphic; Construct multiple control point groups, each control point group including multiple control points symmetrical about a horizontal or vertical axis of symmetry relative to the original graphic; Obtain the optimized graphic coordinates of each control point in the optimized graphic; Based on the optimized graphic coordinates and the original graphic coordinates of each control point, determine whether each control point in each control point group still maintains symmetry in the optimized graphic. If each control point in each control point group remains symmetrical in the optimized graph, then the symmetrical structure is determined to remain symmetrical in the optimized graph.

3. The testing method according to claim 2, characterized in that, The construction of multiple control point groups includes: Based on the relative positional relationship between each control point and other control points within a preset range around it, an identifier number is generated for each control point, so that a pair of control points that are symmetrical about any horizontal or vertical axis of symmetry of the original graphic use the same identifier number. Each of the control points using the same identifier number is considered as a group of control points.

4. The testing method according to claim 3, characterized in that, The step of determining the identifier of each control point based on its relative position to other control points within a preset range, so that a pair of control points symmetrical to any horizontal or vertical axis of symmetry of the original graphic uses the same identifier, includes: Traverse all the control points and obtain the surrounding preset range centered on the traversed control point; Using the surrounding preset range as the calculation window, and using all the control points within the calculation window as each pixel point, the image hash value of the calculation window is calculated; The image hash value of the calculation window is used as the identifier of the control point being traversed.

5. The testing method according to claim 3, characterized in that, Following the step of constructing multiple control point groups, the method further includes: Determine whether the number of control points in each control point group is even. If so, then it is determined that the original graphic has the symmetrical structure.

6. The testing method according to claim 2, characterized in that, The step of determining whether each control point in each control point group still maintains symmetry in the optimized graphic based on the optimized graphic coordinates and the original graphic coordinates of each control point includes: Calculate the displacement vector of each control point based on the optimized graphic coordinates and the original graphic coordinates of each control point; Traverse all the control point groups and determine whether the magnitudes of the displacement vectors of all the control points in the traversed control point groups are equal; If they are all equal, then calculate the sum of the X-axis component vectors and the sum of the Y-axis component vectors of the displacement vectors of all the control points in the traversed control point group. Based on the calculated sum of the X-axis component vectors and the sum of the Y-axis component vectors, it is determined that each control point in the traversed control point group remains symmetrical in the optimized graph.

7. The testing method according to claim 1, characterized in that, The original graphic is a Manhattan structure graphic; or The original graphic is a graphic obtained by rounding the corners of the Manhattan structure; or The original graphic is a polygon composed of curves.

8. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the steps of the method for inspecting a curve mask layout as described in any one of claims 1 to 7.

9. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the method for verifying a curve mask layout as described in any one of claims 1 to 7.

10. A computer device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method for inspecting a curve mask pattern according to any one of claims 1 to 7.

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