Optical proximity correction method and computer readable storage medium

Abstract

The application provides an optical proximity correction method and a computer readable storage medium, comprising: performing edge extension processing on a main pattern corresponding to a screened first correction pattern to obtain a second correction pattern, and then performing partial pattern removal on the inside of the second correction pattern; thus, by performing edge extension processing on the main pattern, the lengths of each line edge (for example, the long side that may be elongated) of the main pattern with long and short side ratio related defects after optical proximity correction are similar (or the same), so as to reserve space for subsequent partial pattern removal, and also ensure that the size of a third correction pattern obtained after the partial pattern is removed still meets the design requirements. Then, by using the partial pattern of the pattern obtained after the edge extension processing, the partial line edge of the pattern is cut off / removed along the direction of the line edge that may be elongated, so as to reduce the total length of the line edge, and then to reduce the long and short side ratio of the pattern and increase the photolithography process window.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to an optical proximity correction method and a computer-readable storage medium. Background Technology

[0002] To eliminate the effects of optical proximity, the pattern on the actual manufactured photomask (layout) differs from the desired lithographic pattern. The pattern on the photomask undergoes optical proximity correction. Furthermore, as the critical dimension (CD) shrinks, the linewidth of the pattern on the mask can be as small as one-third of the wavelength of light. In addition to the necessary optical proximity correction, sub-resolution assistant features (SRAFs) are typically added around the exposed pattern. These sub-resolution assistant features (also simply called assistant features) are only placed on the photomask and do not transfer to the semiconductor device after actual exposure. They merely increase the focus depth of the adjacent exposed patterns, improving exposure accuracy.

[0003] For more advanced technology nodes, the hole layer design in the later stages of the process involves very dense spacing and a highly complex structure. To achieve the goal of minimizing edge position errors, many large aspect ratio patterns will be formed on the optically proximity-corrected layout. However, during mask manufacturing, these large aspect ratio patterns exhibit significantly larger feature size errors (negative errors in the length direction and positive errors in the width direction).

[0004] To address the problems caused by the appearance of large aspect ratio graphics, existing technologies generally involve adjusting the shape of auxiliary graphics or limiting the aspect ratio of the corrected graphics. However, for dense graphics, there is insufficient space to insert auxiliary graphics; limiting the aspect ratio, however, forcibly changing the graphic size can lead to non-convergence after OPC, and this method cannot be used for some process layers with strict feature size requirements. Summary of the Invention

[0005] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions that follow.

[0006] One objective of this application is to provide an optical proximity correction method and a computer-readable storage medium to reduce the aspect ratio of large aspect ratio patterns, increase the photolithography process window of the main pattern in the via layer layout, improve the accuracy and efficiency of optical proximity correction, and reduce correction costs.

[0007] In a first aspect, to achieve the above objectives, one embodiment of this application provides an optical proximity correction method, comprising:

[0008] At least one optical proximity correction is performed on each of the main graphics in the initial layout to obtain a first corrected graphic for each of the main graphics.

[0009] Determine the aspect ratio of each of the first corrected graphics, and select the first corrected graphics whose aspect ratio meets the preset range.

[0010] The first corrected graphic or its corresponding main graphic is subjected to edge expansion processing to obtain the second corrected graphic.

[0011] Remove a portion of the second corrected graphic to obtain the third corrected graphic.

[0012] Determine whether the edge position error of the third corrected graphic is within the allowable range. If not, return to the step of expanding the edge of the selected first corrected graphic or its corresponding main graphic. If yes, end the optical proximity correction.

[0013] Furthermore, the preset range can be greater than a set value, and the set value can be greater than or equal to 1.5.

[0014] Further, the main graphic corresponding to the first corrected graphic selected is determined as the target main graphic; the step of obtaining the second corrected graphic includes:

[0015] Move all the edges of the target main graphic outward along the normal direction by a first offset.

[0016] Alternatively, first determine the long side of the first corrected graphic that has been filtered out, and then move the determined long side outward along its normal by a first offset.

[0017] Furthermore, the value range of the first offset is [M1, M2), where M1 is the length difference between the long side and the short side of the first corrected graphic selected, and M2 is the length of the short side of the first corrected graphic selected.

[0018] Furthermore, the portion of the second corrected graphic to be removed includes at least two sub-graphics, the shape of which includes regular polygons, and the regular polygons include rectangles.

[0019] Furthermore, the area of ​​the partial graphic is smaller than the area of ​​the selected first modified graphic or its corresponding main graphic.

[0020] Further, the step of removing a portion of the second corrected image to obtain the third corrected image includes:

[0021] Determine the initial values ​​of the long side and the short side of the sub-figure, and determine the initial value of the spacing between the long side of the sub-figure and the line edge of the second modified figure.

[0022] Based on the initial values ​​of the long side, the short side, and the spacing, the graphics corresponding to the sub-graphics are removed from the second corrected graphic.

[0023] Determine the first edge position error in the horizontal direction of the second corrected graphic after removing the portion of the graphic, and determine the second edge position error in the vertical direction of the second corrected graphic after removing the portion of the graphic.

[0024] Determine whether both the first edge position error and the second edge position error are within the allowable range; if not, adjust the initial value of the long side of the sub-graphic using a preset formula, and return to execute the step of removing the graphic corresponding to the sub-graphic in the second corrected graphic based on the initial value of the long side, the initial value of the short side, and the initial value of the spacing; if yes, use the second corrected graphic after removing the part of the graphic as the third corrected graphic.

[0025] Furthermore, the length of the short side of the sub-pattern does not exceed the resolution limit of the lithography machine.

[0026] Furthermore, the preset formula is:

[0027] C = [(x1 + y1) / 2] * k;

[0028] Where C is the length of the long side of the sub-graphic; x1 is the first edge position error of the second corrected graphic after removing the part of the graphic in the horizontal direction; y1 is the second edge position error of the second corrected graphic after removing the part of the graphic in the vertical direction; and k is the iteration coefficient.

[0029] Secondly, the present invention also provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; the memory is used to store computer programs; and the processor is used to implement the optical proximity correction method steps as described above when executing the program stored in the memory.

[0030] Thirdly, the present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the optical proximity correction method steps as described above.

[0031] Compared with the prior art, the technical solution provided by the present invention has at least one of the following beneficial effects:

[0032] The optical proximity correction method provided in this application includes: performing optical proximity correction on each main graphic in the initial layout at least once to obtain a first corrected graphic for each of the main graphics;

[0033] Determine the aspect ratio of each of the first correction graphics and select the first correction graphics whose aspect ratio meets the preset range; perform edge expansion processing on the selected first correction graphics or their corresponding main graphics to obtain the second correction graphics; remove part of the second correction graphics to obtain the third correction graphics; determine whether the edge position error of the third correction graphics is within the allowable range. If not, return to the step of performing edge expansion processing on the selected first correction graphics or their corresponding main graphics. If yes, end the optical proximity correction.

[0034] In this application, the main pattern corresponding to the first selected corrected pattern is first expanded to obtain the second corrected pattern. Then, part of the pattern is removed from the interior of the second corrected pattern. An unexpected effect is achieved: a new correction method for via layer layout is proposed. By expanding the main pattern, the lengths of the edges of the main pattern that have defects related to large aspect ratios after optical proximity correction (such as long edges that may be elongated) are similar (or the same). This provides space for subsequent removal of part of the pattern and ensures that the size of the third corrected pattern obtained after removing part of the pattern still meets the design requirements. Then, by removing part of the pattern obtained after the expansion process, part of the edge of the pattern is cut / removed along the direction of the edge that may be elongated in the main pattern, so as to reduce the total length of the edge, thereby reducing the aspect ratio of the pattern and increasing the photolithography process window. Since the line width (short side length) of the sub-patterns removed in this application does not exceed the resolution limit of the lithography machine, although multiple holes exist in the final corrected third pattern, the light intensity of other pattern areas adjacent to the sub-pattern will be superimposed during actual exposure, so a continuous exposure pattern can still be obtained. Attached Figure Description

[0035] The accompanying drawings provide a more in-depth understanding of embodiments of this application and are incorporated herein by reference as a whole. These drawings and descriptions are used to illustrate the principles of some embodiments. It should be noted that all drawings are schematic diagrams and are for illustrative and drawing convenience, and relative sizes and proportions have been adjusted. The same symbols represent corresponding or similar features in different embodiments.

[0036] Figure 1 This is a schematic flowchart of an optical proximity correction method in an embodiment of this application.

[0037] Figure 2 is a schematic diagram of the initial layout after conventional optical proximity correction in an embodiment of this application.

[0038] Figure 3 This is a schematic diagram illustrating the process of processing the main graphic corresponding to the first corrected graphic selected in this embodiment of the application to obtain the second corrected graphic.

[0039] Figure 4 This application utilizes the following in its embodiments. Figure 1 The diagram shows a third correction pattern obtained by the optical proximity correction method.

[0040] In the accompanying drawings, the same parts are referred to by the same reference numerals, and the drawings are not drawn to scale. Detailed Implementation

[0041] To make the technical solutions and advantages of the embodiments of this application clearer, the technical solutions of this application will be further described in detail below with reference to the accompanying drawings and embodiments. Although exemplary implementation methods of this application are shown in the accompanying drawings, it should be understood that this application can be implemented in various forms and should not be limited to the implementation methods described herein. Rather, these implementation methods are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art.

[0042] The present application is described in more detail below by way of example with reference to the accompanying drawings. The advantages and features of the present application will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, intended only to facilitate and clarify the illustration of the embodiments of the present application. It is understood that the terms "on," "above," and "over" in this application should be interpreted in the broadest sense, such that "on" means not only "on" something without any intervening feature or layer (i.e., directly on something), but also includes "on" something with an intervening feature or layer.

[0043] Furthermore, for ease of description, regional relative terms such as “on,” “above,” “above,” “upper,” “above,” “upper,” etc., may be used herein to describe the relationship between one element or feature and another element or feature as shown in the figures. In addition to the orientations depicted in the figures, regional relative terms are intended to cover different orientations of the device in use or operation. The device may be oriented in other ways (rotated 90 degrees or in other orientations) and the regional relative descriptive terms used herein may be interpreted accordingly.

[0044] In the embodiments of this application, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be noted that the technical solutions described in the embodiments of this application can be arbitrarily combined without conflict.

[0045] As mentioned above, for more advanced technology nodes, the hole layer design in the back-end processes features very dense spacing and a very complex structure. To achieve the goal of minimizing edge position error, many large aspect ratio patterns will be formed on the optically proximal correction (OPC) layout. During mask manufacturing, these large aspect ratio patterns exhibit significantly larger feature size errors (negative errors in the length direction and positive errors in the width direction). To address the problems caused by these large aspect ratio patterns, existing technologies generally adjust the shape of auxiliary patterns or limit the aspect ratio of the corrected patterns. However, for dense patterns, there is insufficient space to insert auxiliary patterns; limiting the aspect ratio, however, forcibly changing the pattern size, leads to non-convergence after OPC, and this method cannot be used for some process layers with strict feature size requirements.

[0046] To overcome the aforementioned deficiencies in the prior art, this application provides an optical proximity correction method and a computer-readable storage medium to reduce the aspect ratio of large aspect ratio patterns, increase the photolithography process window of the main pattern in the via layer layout, improve the accuracy and efficiency of optical proximity correction, and reduce correction costs.

[0047] The optical proximity correction method of this application will be further described below with reference to the accompanying drawings and embodiments.

[0048] Please refer to Figure 1 The illustration shown is a flowchart of an optical proximity correction method according to an embodiment of this application. Figure 1 As shown, the optical proximity correction method may include at least the following steps:

[0049] Step S101: Perform at least one optical proximity correction on each main graphic in the initial layout to obtain a first corrected graphic for each main graphic.

[0050] Step S102: Determine the aspect ratio of each of the first corrected graphics, and select the first corrected graphics whose aspect ratio meets the preset range.

[0051] Step S103: Expand the edges of the selected first corrected graphic or its corresponding main graphic to obtain the second corrected graphic.

[0052] Step S104: Remove a portion of the second corrected graphic to obtain the third corrected graphic.

[0053] Step S105: Determine whether the edge position error of the third corrected graphic is within the allowable range. If not, return to the step of expanding the edge of the selected first corrected graphic or its corresponding main graphic. If yes, end the optical proximity correction.

[0054] In step S101 above, an initial layout can be provided, which includes multiple main patterns; preferably, the initial layout is a via layer layout; the main patterns are square patterns. In one embodiment, the spacing between at least two adjacent main patterns in the multiple main patterns of the initial layout is less than the spacing required for adding auxiliary patterns, thus preventing the addition of auxiliary patterns during actual optical proximity correction (hereinafter referred to as OPC correction); in other embodiments, since the main patterns in the initial layout have strict feature size requirements, their aspect ratio cannot be limited during actual OPC correction, but this is not a limitation. Next, conventional optical proximity correction can be performed on the multiple main patterns in the initial layout to obtain a first corrected pattern for each main pattern.

[0055] In some examples, each main graphic in the initial layout can undergo at least one optical proximity correction. For instance, auxiliary graphics can be added around each main graphic, and the edges of the main graphics with added auxiliary graphics can be divided into multiple line segments. Then, the edges can be shrunk or expanded along the normal direction of each line segment (the normal direction is perpendicular to the extension direction of each line segment) to obtain the desired result. Figure 2The first revised layout is shown. The first revised layout includes, but is not limited to, the first revised graphic 11 after correcting each main graphic 10 in the initial layout and the auxiliary graphics 20 added to its adjacent areas. Obviously, for via layer / hole layer layouts, in order to minimize edge placement error (EPE) during OPC correction, many graphics with large aspect ratios, such as the first revised graphic 11, are generated based on the surrounding graphic environment. It should be understood that, for ease of observation that the first revised graphic 11 is a graphics with a large aspect ratio, the corresponding figures in this embodiment are all drawn by stacking the first revised graphic 11 and its corresponding main graphic 10 together with their centers overlapping.

[0056] In step S102 above, following step S101 where the first modified graphics 11 of each main graphic are obtained, all the first modified graphics 11 can be traversed, and the aspect ratio of each first modified graphics 11 can be calculated, that is, the ratio of the length of the long side to the length of the short side of the first modified graphics 11 can be calculated. Then, the first modified graphics 11 whose aspect ratio meets the preset range are selected, for example, all the first modified graphics 11 whose aspect ratio is greater than or equal to the set value of 1.5 are selected, and the main graphic corresponding to the selected first modified graphics 11 is used as the target main graphic for subsequent steps S103 to S105. The set value can also be 1.6, 1.7, 2.0, 2.5, etc., and is not limited thereto.

[0057] In steps S103 and S104 above, the first corrected graphic 11 or its corresponding main graphic 10 can be expanded to obtain a second corrected graphic 12; then, a portion of the second corrected graphic 12 is removed to obtain a third corrected graphic 13. The portion of the second corrected graphic to be removed includes at least two sub-graphics, the shape of which includes regular polygons, and the regular polygons include rectangles. The first offset value ranges from [M1, M2), where M1 is the length difference between the long and short sides of the first corrected graphic 11, and M2 is the length of the short side of the first corrected graphic 11. Furthermore, the area of ​​the removed portion of the graphic must be smaller than the area of ​​the main graphic 10 corresponding to the first corrected graphic 11; for example, the area of ​​the removed portion of the graphic can be less than two-fifths of the area of ​​the main graphic 10.

[0058] In a preferred example, all lines of the main graphic 10 (hereinafter referred to as the target main graphic) corresponding to the first corrected graphic 11 can be moved outward by a first offset along the normal direction. For example... Figure 3As shown, all the edges of the main graphic 10 corresponding to the first corrected graphic 11 can be moved outward along the normal direction by a first offset 'a', where the value of 'a' ranges from [M1, M2), where M1 is the length difference between the long and short sides of the selected first corrected graphic 11, and M2 is the length of the short side of the selected first corrected graphic 11. In this embodiment, the first offset 'a' is preferably M1, for example, equal to 20 nm. This results in a second corrected graphic 12 with an enlarged area. Then, a portion of the graphic is removed from the second corrected graphic 12, for example, removing two sub-graphics 121 that are positioned opposite each other along the horizontal direction X, i.e., removing a portion of the graphic from the second corrected graphic 12, to obtain... Figure 4 The third corrected figure 13 is shown. Among them, the width between each sub-figure 121 and the line edge of the second corrected figure 12 along the horizontal direction X is A, the length of the short side of the sub-figure 121 along the horizontal direction X is B, and the length of the long side of the sub-figure 121 along the vertical direction Y is C.

[0059] It should be noted that the length B of the short side of the removed sub-pattern 121 must not exceed the resolution limit of the lithography machine. In this way, although the final corrected third pattern 13 contains multiple holes, the light intensity of other pattern areas adjacent to the sub-pattern will be superimposed during actual exposure, so a continuous exposure pattern can still be obtained. That is, it ensures that the corrected pattern corresponding to the main pattern in the through-hole layer layout meets the design requirements, while reducing the aspect ratio of the pattern and increasing the lithography process window.

[0060] In another example, the long side of the selected first modified pattern 11 can be determined first, and then the line containing the determined long side can be moved outward along its normal by a first offset a. The value of a can also be in the range [M1, M2), where M1 is the length difference between the long and short sides of the selected first modified pattern 11, and M2 is the length of the short side of the selected first modified pattern 11. Furthermore, the first offset a is preferably M1, for example, equal to 20 nm. This results in a second modified pattern 12 with an enlarged area. Then, a portion of the pattern is removed from the second modified pattern 12, for example, removing two sub-patterns 121 that are positioned opposite each other along the horizontal direction X, i.e., removing a portion of the pattern from the second modified pattern 12, to obtain... Figure 4 The third corrected figure 13 is shown. Among them, the width between each sub-figure 121 and the line edge of the second corrected figure 12 along the horizontal direction X is A, the length of the short side of the sub-figure 121 along the horizontal direction X is B, and the length of the long side of the sub-figure 121 along the vertical direction Y is C.

[0061] Obviously, regardless of whether the aforementioned method is used to expand the edges of all lines of the main graphic 10 corresponding to the first corrected graphic 11, or to expand the long edge of the first corrected graphic 11, the final shape of the third corrected graphic 13 is approximately the same, thus achieving the same objective. Furthermore, the multiple sub-graphics 121 in this embodiment can be as follows... Figure 3 The sub-figure 121 can be symmetrically arranged along the horizontal direction X, but it can also be arranged asymmetrically. However, it must meet the following length and spacing requirements: the width between the sub-figure 121 and the line edge of the second modified figure 12 along the horizontal direction X is A, the length of the short side of the sub-figure 121 along the horizontal direction X is B, and the length of the long side of the sub-figure 121 along the vertical direction Y is C.

[0062] In step S105 above, after each execution of step S104, it is necessary to determine whether the edge position error of the third corrected pattern 13 is within the allowable range. If not, the process returns to re-execute the step of expanding the edge of the main pattern 10 corresponding to the selected first corrected pattern 11. If yes, the optical proximity correction ends. For example, after the first execution of steps S101 to S105, if it is determined that the edge position error of the third corrected pattern 13 is not within the allowable range (this process is one iteration, i.e., k=1), then it is necessary to return to re-execute steps S103 to S105, and further determine whether the edge position error of the newly determined third corrected pattern 13 is within the allowable range (this process is the second iteration, i.e., k=2). If not, the process returns to execute steps S103 to S105 again until it is determined that the edge position error of the third corrected pattern 13 is within / within the allowable range. This process is repeated k times.

[0063] In this embodiment of the application, the size of the sub-graphic 121 in the removed portion of the graphic can be determined by iterative calculation to obtain the optimal value. For example, the initial value of the long side C of the sub-graphic 121 (e.g., 38nm) and the initial value of the short side B (e.g., 17nm) can be set first, as well as the initial value of the distance A along the horizontal direction X between the long side C of the sub-graphic 121 and the line edge of the second corrected graphic 12 (e.g., 16nm). Then, the first iteration is performed based on the initial value of the long side C, the initial value of the short side B, and the initial value of the distance A. Specifically, the graphic corresponding to the sub-graphic 121 is removed from the second corrected graphic 12 to form the initial shape of the third corrected graphic. Next, the first edge position error x1 of the second corrected graphic 12 after removing the portion of the graphic is determined / calculated in the horizontal direction X, and the second edge position error y1 of the second corrected graphic 12 after removing the portion of the graphic is determined in the vertical direction Y. Then, the size of the sub-graphic 12 is determined. The first edge position error x1 and the second edge position error y1 are both within the allowable range. If not, it indicates that the initial values ​​of the long side C, short side B, and spacing A set in the previous initial settings are unreasonable and need to be adjusted. The following preset formula can be used to adjust only the initial value of the long side C of the sub-graphic (the initial values ​​of A and B are not adjusted), and return to execute the step of removing the graphic corresponding to the sub-graphic in the second corrected graphic 12 based on the initial values ​​of the long side C, short side B, and spacing A to perform the second iteration. This results in the sub-graphic corresponding to the adjusted initial values ​​of the long side C, short side B, and spacing A being used to re-form the third corrected graphic. The first edge position error x1 and the second edge position error y1 are further calculated and confirmed to be within the allowable range until they are within the allowable range. The iteration can then be stopped, and the second corrected graphic after removing the part of the graphic is taken as the third corrected graphic.

[0064] In one embodiment, the preset formula for adjusting the value of the long side C of the sub-graphic 121 proposed in this application can be specifically as follows:

[0065] C = [(x1 + y1) / 2] * k;

[0066] Wherein, C is the length of the long side of the sub-graphic; x1 is the first edge position error of the second corrected graphic after removing the part of the graphic in the horizontal direction X; y1 is the second edge position error of the second corrected graphic after removing the part of the graphic in the vertical direction Y; k is the iteration coefficient; and, the value range of A is preferably 15 nm to 20 nm, the value range of B is preferably 15 nm to 20 nm, and C > M2 / 3 (the value of C is preferably greater than one-third of the length of the long side of the first corrected graphic selected).

[0067] It should be understood that the determination of the first edge position error x1 and the second edge position error y1 in the embodiments of this application may specifically be as follows: using an optical proximity correction model to determine the simulated image of the second corrected image after removing the part of the image; then comparing the offset between the simulated image and the second corrected image after removing the part of the image; and then substituting the offset into the optical proximity correction model to determine the first edge position error x1 and the second edge position error y1, but not limited thereto.

[0068] In summary, the optical proximity correction method provided in this application includes: performing optical proximity correction on each main graphic in the initial layout at least once to obtain a first corrected graphic for each main graphic; determining the aspect ratio of each first corrected graphic and selecting first corrected graphics whose aspect ratio meets a preset range; performing edge expansion processing on the main graphic corresponding to the selected first corrected graphic to obtain a second corrected graphic; removing part of the graphic in the second corrected graphic to obtain a third corrected graphic; determining whether the edge position error of the third corrected graphic is within the allowable range; if not, returning to the step of performing edge expansion processing on the main graphic corresponding to the selected first corrected graphic; if yes, ending the optical proximity correction. In this application, the main pattern corresponding to the first selected corrected pattern is first expanded to obtain the second corrected pattern. Then, partial pattern removal is performed inside the second corrected pattern, resulting in an unexpected effect: a new correction method for via layer layout is proposed. By expanding the main pattern, the lengths of the edges of the main pattern with large aspect ratio defects (such as long edges that may be elongated) after optical proximity correction are made approximately the same (or identical), reserving space for subsequent partial pattern removal and ensuring that the size of the third corrected pattern obtained after partial pattern removal still meets the design requirements. Then, by removing part of the pattern obtained after the edge expansion process, part of the edge of the pattern is cut / removed along the direction of the edge that may be elongated in the main pattern, thereby reducing the total length of the edge and thus reducing the aspect ratio of the pattern and increasing the photolithography process window. Since the line width (short side length) of the sub-patterns in the removed part of the pattern in this application does not exceed the resolution limit of the lithography machine, although there are multiple holes in the final corrected third pattern, the light intensity of other pattern areas adjacent to the sub-pattern will be superimposed during actual exposure, so a continuous exposure pattern can still be obtained.

[0069] This invention also provides an electronic device, including a processor, a communication interface, a memory, and a communication bus. The processor, communication interface, and memory communicate with each other through the communication bus. The memory is used to store computer programs. When the processor executes the program stored in the memory, it implements an optical proximity correction method provided by this invention.

[0070] In addition, other implementations of the optical proximity correction method implemented by the processor executing the program stored in the memory are the same as those mentioned in the aforementioned method embodiment section, and will not be repeated here.

[0071] The communication bus mentioned in the control terminal above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0072] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0073] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0074] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0075] In another embodiment of the present invention, a computer-readable storage medium is also provided, which stores instructions that, when executed on a computer, cause the computer to perform an optical proximity correction method as described in any of the above embodiments.

[0076] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0077] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0078] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the embodiments of apparatus, electronic devices, and computer-readable storage media are basically similar to the method embodiments, and therefore the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0079] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. An optical proximity correction method, characterized in that, include: At least one optical proximity correction is performed on each of the main graphics in the initial layout to obtain a first corrected graphic for each of the main graphics; Determine the aspect ratio of each of the first corrected graphics, and select the first corrected graphics whose aspect ratio meets the preset range; The first corrected graphic or its corresponding main graphic is subjected to edge expansion processing to obtain the second corrected graphic; Remove a portion of the second corrected graphic to obtain the third corrected graphic; Determine whether the edge position error of the third corrected graphic is within the allowable range. If not, return to the step of expanding the edge of the selected first corrected graphic or its corresponding main graphic. If yes, end the optical proximity correction.

2. The optical proximity correction method as described in claim 1, characterized in that, The preset range is greater than a set value, and the set value is greater than or equal to 1.

5.

3. The optical proximity correction method as described in claim 2, characterized in that, The first corrected graphic selected or its corresponding main graphic is determined as the target main graphic; The step of obtaining the second corrected graphic includes: Move all the edges of the target main graphic outward along the normal direction by a first offset amount; Alternatively, first determine the long side of the first corrected graphic that has been filtered out, and then move the determined long side outward along its normal by a first offset.

4. The optical proximity correction method as described in claim 3, characterized in that, The first offset value ranges from [M1, M2), where M1 is the length difference between the long side and the short side of the first corrected graphic selected, and M2 is the length of the short side of the first corrected graphic selected.

5. The optical proximity correction method as described in claim 1, characterized in that, The portion of the second corrected graphic to be removed includes at least two sub-graphics, the shape of which includes regular polygons, and the regular polygons include rectangles.

6. The optical proximity correction method as described in claim 5, characterized in that, The area of ​​the partial graphic is smaller than the area of ​​the first corrected graphic selected or its corresponding main graphic.

7. The optical proximity correction method as described in claim 5, characterized in that, The step of removing a portion of the second corrected graphic to obtain the third corrected graphic includes: Determine the initial values ​​of the long side and the short side of the sub-figure, and determine the initial value of the spacing between the long side of the sub-figure and the line edge of the second modified figure; Based on the initial values ​​of the long side, the short side, and the spacing, the graphics corresponding to the sub-graphics are removed from the second corrected graphic; Determine the first edge position error in the horizontal direction of the second corrected graphic after removing the portion of the graphic, and determine the second edge position error in the vertical direction of the second corrected graphic after removing the portion of the graphic; Determine whether both the first edge position error and the second edge position error are within the allowable range; if not, adjust the initial value of the long side of the sub-graphic using a preset formula, and return to execute the step of removing the graphic corresponding to the sub-graphic in the second corrected graphic based on the initial value of the long side, the initial value of the short side, and the initial value of the spacing; if yes, use the second corrected graphic after removing the part of the graphic as the third corrected graphic.

8. The optical proximity correction method as described in claim 7, characterized in that, The length of the short side of the sub-pattern does not exceed the resolution limit of the lithography machine.

9. The optical proximity correction method as described in claim 7, characterized in that, The preset formula is: C = [(x1 + y1) / 2] * k; Where C is the length of the long side of the sub-graphic; x1 is the first edge position error of the second corrected graphic after removing the part of the graphic in the horizontal direction; y1 is the second edge position error of the second corrected graphic after removing the part of the graphic in the vertical direction; and k is the iteration coefficient.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the optical proximity correction method as described in any one of claims 1 to 9.

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