CN117855039B

CN117855039B - OPC correction method

Info

Publication number: CN117855039B
Application number: CN202410259334.4A
Authority: CN
Inventors: 赵广; 罗招龙
Original assignee: Nexchip Semiconductor Corp
Current assignee: Nexchip Semiconductor Corp
Priority date: 2024-03-07
Filing date: 2024-03-07
Publication date: 2024-05-28
Anticipated expiration: 2044-03-07
Also published as: CN117855039A

Abstract

The invention provides an OPC correction method, and particularly provides a novel corner structure for improving the line pattern correction result of a metal layer on a mask plate in the OPC correction method, and provides an OPC correction method for directly adjusting the shape of the corner of the line pattern on the mask plate from a right angle which is easy to generate a corner rounding effect to other shapes which are difficult to generate the corner rounding effect in the OPC correction process of the line pattern with the corner on the metal layer based on the novel corner structure, thereby realizing the effect of effectively reducing the probability of generating the corner rounding effect of the line pattern with the corner on the metal layer, namely ensuring that the metal line structure formed on an actual silicon wafer by utilizing the corrected mask plate meets the design requirement, and simultaneously increasing the overlapping area of the metal layer structure and the through hole layer structure on the upper layer and the lower layer and improving the product yield of a semiconductor device.

Description

OPC correction method

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to an OPC correction method.

Background

In the integrated circuit manufacturing process, the connection of the rear metal layer and the through hole layer plays a critical role in the performance of the device, if the coverage rate of the metal layer and the through hole layer does not reach the standard, poor conduction performance and even failure among different metal layers can be caused, and finally the yield of the product is reduced.

Along with the advancement of photolithography process nodes, the pattern size is smaller and smaller, the influence of light diffraction on exposure imaging is larger and larger, and the corner rounding effect (corner rounding) of the pattern is also more obvious, especially in the application of the later metal layer layout and the through hole layer layout in the integrated circuit manufacturing process.

At present, the coverage rate of the metal layer layout design line end and the through hole layer is reduced due to the influence of the corner rounding effect at the corner position of the metal layer layout design line end, and the problem that the through hole layer is directly exposed is also caused when the coverage rate is serious.

Disclosure of Invention

The invention aims to provide an OPC correction method, which is used for correcting the shape of a convex corner of a line pattern on a metal layer on a mask plate, so that the shape of the convex corner is adjusted from a right angle which is easy to generate a corner rounding effect to other shapes with low probability of generating the corner rounding effect, the distortion of the line pattern with the convex corner is effectively reduced, and the problems of process hot spots such as errors, insufficient coverage area and the like of a metal layer and a through hole lamination layer caused by severe rounding of the convex corner are solved.

In order to solve the above technical problems, the present invention provides an OPC correction method, which may include the following steps:

And obtaining a plurality of original patterns on the mask, wherein the original patterns are line patterns with convex corners for forming a metal layer on the wafer.

And performing first OPC correction and photoetching simulation on the plurality of original patterns on the mask plate to obtain a first simulation pattern of each original pattern.

And determining a distance difference R between each original graph and the salient angle corners contained in the corresponding first simulation graph, and performing corner processing on the original graph with the distance difference R larger than a preset threshold value so as to modify the shape of the salient angle corners of the original graph into a target shape.

Further, the lobe corner may specifically be an angle equal to a first angle between two adjacent line edges in the line pattern, and the first angle may be 90 °.

Furthermore, before the first OPC correction is performed on the plurality of original patterns on the mask, at least one auxiliary pattern may be added in the peripheral area of the line pattern according to a preset auxiliary pattern adding rule.

Further, the step of determining the distance difference R between the lobe corners included in each original pattern and the first simulation pattern corresponding to the original pattern may specifically include:

And overlapping the original graph and the corresponding first simulation graph.

And taking the center of the overlapped original graph and the corresponding first simulation graph as a starting point, making a line segment in the corner direction of the convex angle of the original graph or the first simulation graph, and enabling the line segment and the line edges on the original graph and the corresponding first simulation graph forming the corner of the respective convex angle to form an intersection point respectively.

And taking the distance between the two intersection points as the distance difference R.

Further, an included angle between the line segment and a vertical line of one line edge of the lobe corner of the original graph or the first simulation graph corresponding to the original graph is a second angle, and the range of the second angle may be 30 ° to 60 °.

Further, the step of performing corner processing on the original graph with the distance difference R greater than the preset threshold may specifically include:

And carrying out corner cutting treatment on the lobe corners of the original graph to obtain a corner cutting opening.

And adding a rectangular correction pattern at the corner cutting opening so as to adjust the shape of the corner of the convex angle from a right angle to a convex shape.

The midpoint of the outer side edge of the rectangular correction pattern or the convex shape coincides with the vertex of the convex corner of the original pattern, and the outer side edge of the rectangular correction pattern or the convex shape is parallel to the corner cut opening side edge of the original pattern.

and (3) carrying out outward edge expansion treatment on the vertex of the convex corner of the original graph so as to adjust the shape of the convex corner from a right angle to a convex shape.

The midpoint of the outer side edge of the convex shape coincides with the vertex of the convex corner of the original graph, and the outer side edge of the convex shape is perpendicular to a line segment passing through the center of the original graph and the vertex of the convex corner before adjustment.

Further, the value range of the outer side edge of the "convex" shape or the outer side edge of the rectangular correction pattern may specifically be: 1/2R to 5R.

Further, the step of performing the first OPC correction on the plurality of original patterns on the mask plate may specifically include: and carrying out outward edge expansion treatment or inward edge contraction treatment on each line edge of the original graph along the direction perpendicular to the line edge.

Further, after adjusting the shape of the lobe corner of the original pattern from a right angle to a "convex" shape, the OPC correction method provided by the present invention may further include the following steps:

performing a second OPC correction on the original graph to obtain a second simulation graph of the original graph;

determining a distance difference R' between the convex corners of the convex shapes, which are adjusted to be the convex shapes, of the original patterns and the corresponding second simulation patterns;

And if the distance difference R 'is larger than the preset threshold value, adjusting the outer side edge of the convex shape or the outer side edge of the rectangular correction pattern, and returning to execute the step of performing the second OPC correction on the original pattern to obtain a second simulation pattern of the original pattern until the distance difference R' is smaller than the preset threshold value.

In a second aspect, based on the same inventive concept as the OPC correction method described above, the embodiment of the present invention further provides a mask, where the mask may specifically be manufactured by using the mask plate making pattern obtained by the OPC correction method described above.

In a third aspect, based on the OPC correction method as described above, the present invention further provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, where the processor, the communication interface, and the memory complete communication with each other through the communication bus.

And a memory for storing a computer program.

And a processor for implementing the steps of the OPC correction method as described above when executing the program stored in the memory.

Compared with the prior art, the technical scheme provided by the invention has at least one of the following beneficial effects:

In the OPC correction method provided by the present invention, after obtaining a plurality of line patterns with lobe corners for forming a metal layer on a wafer on a mask, performing conventional OPC correction and lithography simulation on the line patterns, determining a distance difference R between each of the original patterns and the lobe corners included in the corresponding first simulation pattern, and performing corner processing on the original pattern with the distance difference R greater than a preset threshold value, so as to modify the shape of the lobe corner of the original pattern into a target shape, thereby obtaining unexpected effects that: the novel corner structure is used for improving the line pattern correction result of the metal layer on the mask plate in the OPC correction method, and the novel corner structure is used for directly adjusting the shape of the lobe corner of the line pattern on the mask plate from a right angle which is easy to generate a corner rounding effect to other shapes (novel corner structure) which are difficult to generate the corner rounding effect in the OPC correction process of the line pattern with the lobe corner on the metal layer, so that the probability of generating the corner rounding effect of the line pattern with the lobe corner on the metal layer is effectively reduced, namely the metal line structure formed on an actual silicon wafer by utilizing the corrected mask plate is ensured to meet the design requirement, the overlapping area of the formed metal layer structure and the through hole layer structure on the upper layer and the lower layer is increased, and the aim of improving the product yield of a semiconductor device is finally realized.

Drawings

Fig. 1 is a schematic diagram of a structure in which a corner rounding effect occurs in a lobe corner obtained by performing OPC correction on a line pattern having the lobe corner on a metal line layer by using a conventional OPC correction method in the prior art.

FIG. 2 is a flowchart of an OPC correction method according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a line pattern with a lobe corner according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of a local enlarged structure of a distance difference R between the original pattern and the corresponding first simulation pattern by using the OPC correction method provided in the present embodiment to solve the distance difference R between the included lobe corners.

FIG. 5 is a comparison diagram of partial layouts before and after chamfering the corners of the line pattern shown in FIG. 3 by using the OPC correction method shown in FIG. 2 according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of a partial layout of a line pattern obtained by chamfering the lobe corners of the line pattern shown in fig. 3 by using the OPC correction method shown in fig. 2 according to an embodiment of the present invention.

Detailed Description

In order to make the technical scheme and advantages of the embodiments of the present invention more clear, the technical scheme of the present invention will be further described in detail below with reference to the accompanying drawings and the embodiments. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The invention is more particularly described by way of example in the following paragraphs with reference to the drawings. Advantages and features of the invention will become more apparent from the following description and from the claims. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for convenience and clarity in aiding in the description of embodiments of the invention. It is to be understood that the meaning of "on … …", "over … …" and "over … …" in this disclosure should be read in the broadest manner so that "on … …" means not only that it is "on" something with no intervening features or layers therebetween (i.e., directly on something), but also that it is "on" something with intervening features or layers therebetween.

Further, spatially relative terms such as "on … …," "over … …," "above … …," "upper" and the like may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated. In addition to the orientations depicted in the drawings, the spatially relative terms are intended to encompass different orientations of the device in use or operation. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In embodiments of the present invention, the terms "first," "second," and the like are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. The technical schemes described in the embodiments of the present invention may be arbitrarily combined without any collision.

According to the related art, in the optical proximity correction field, for a line pattern with a lobe corner, a common OPC correction method is, for example, model-based OPC correction, specifically, the edge of a mask design pattern can be first identified by OPC software, and then the edge of the mask design pattern is cut into a plurality of small correction line segments, so that the edge of each line segment can move freely. The OPC software then simulates the pattern after lithography exposure, and compares it with the design target pattern of the reticle, the difference between them being called edge placement Error (EPE, edge Placement Error), which is an indicator for measuring the correction quality. And the OPC software moves the edge position of the mask design graph when running, and calculates the corresponding edge placement error. This process is repeated until the calculated edge placement error reaches an acceptable value.

However, the coverage rate of the metal layer on the mask plate with the through hole layer is reduced due to the effect of corner rounding effect at the corner (lobe corner) of the line pattern on the metal layer, and the problem of directly exposing the through hole layer is also caused in severe cases, as shown in fig. 1.

In view of this problem, the present inventors found that, no matter how many times the conventional OPC correction such as stretching or retracting of the line pattern corner (lobe corner) on the metal layer on the mask is performed, the probability of occurrence of the corner rounding effect is still high, and the corner pattern distortion is serious.

In other words, the OPC correction method provided by the invention corrects the shape of the convex corner of the line pattern on the metal layer on the mask plate, so that the shape of the convex corner is adjusted from a right angle which is easy to generate the corner rounding effect to other shapes which have low probability of generating the corner rounding effect or are difficult to generate the corner rounding effect, the distortion of the line pattern with the convex corner can be effectively reduced, and the problems of process hot spots such as errors of the metal layer and the through hole lamination layer, insufficient coverage area and the like caused by severe rounding of the convex corner are solved.

An OPC correction method provided in the embodiment of the present invention will be specifically described with reference to fig. 2 to 6.

Referring to fig. 2, fig. 2 is a flowchart of an OPC correction method according to an embodiment of the present invention, the method includes the following steps:

Step S201, obtaining a plurality of original patterns on a mask, wherein the original patterns are line patterns with convex corners for forming a metal layer on a wafer.

As an example, the line graph with the lobe corner provided in the embodiment of the present invention is specifically configured to form a corresponding metal line structure on a metal layer on a wafer, and the lobe corner may be specifically located at an angle equal to a first set angle between two adjacent line edges in the line graph, where the first angle is 90 °, as shown in fig. 3. In the schematic layout diagram of the line graph with the lobe corners shown in fig. 3, the right-angle area encircled by the schematic layout diagram is the lobe corner of the line graph.

Step S202, performing first OPC correction and lithography simulation on the plurality of original patterns on the mask plate to obtain a first simulation pattern of each original pattern.

In this embodiment, after the plurality of original patterns on the mask are obtained, at least one auxiliary pattern is added in the peripheral area of the line pattern according to a preset auxiliary pattern adding rule, so as to adjust the influence of different patterns and densities on the correction result of the line pattern, and then the first OPC correction and the lithography simulation are performed on the plurality of original patterns on the mask.

As a preferable example, the step of performing the first OPC correction on the plurality of original patterns on the mask plate is a process of performing, for each line edge of the original patterns, an outward edge expansion process or an inward edge contraction process along a direction perpendicular to the line edge.

Step S203, determining a distance difference R between each of the original patterns and the lobe corners included in the corresponding first simulation pattern, and performing corner processing on the original pattern with the distance difference R greater than a preset threshold value, so as to modify the shape of the lobe corner of the original pattern into a target shape.

As a preferred example, the step of determining the distance difference R between the lobe corners of each original graphic and the corresponding first simulation graphic in the embodiment of the present invention may specifically include:

And step 203.1, overlapping the original graph and the corresponding first simulation graph.

Step S203.2, taking the center of the overlapped original pattern (the line pattern with the lobe corner for forming the metal layer on the wafer) and the corresponding first simulation pattern (the actual pattern formed by exposing on the test wafer based on the mask) as a starting point, making a line segment in the lobe corner direction of the original pattern or the first simulation pattern, and making the line segment and the line edges on the original pattern and the corresponding first simulation pattern forming the respective lobe corners thereof form an intersection point respectively.

And step S203.3, taking the distance between the two intersection points as the distance difference R.

In this embodiment, in order to quantify the corner rounding effect of the line patterns with the lobe corners of the metal layer on the mask, a distance difference parameter R (distance difference R for short) is introduced, where the distance difference R represents the pattern difference between the line patterns on the mask and the first simulation patterns corresponding to the line patterns at the lobe corners, so that the greater the distance difference R, the more serious the corner rounding effect occurs in the line patterns with the lobe corners of the metal layer on the mask.

Referring to fig. 4, fig. 4 is a schematic diagram of a local enlarged structure of a distance difference R between the original pattern and the corresponding first simulation pattern by using the OPC correction method provided in the present embodiment to solve the distance difference R between the included lobe corners.

As shown in fig. 4, in order to determine the distance difference R introduced in this embodiment, the original pattern, that is, the line pattern S1 with the lobe corner and the first simulation pattern S2 corresponding thereto are overlapped, then a line segment passing through the center point 0 of the overlapped pattern is made in the lobe corner area of the two overlapped patterns, and the line segment, the line pattern S1 and the first simulation pattern S2 corresponding thereto have an intersection point, such as an intersection point a and an intersection point b, respectively, in the lobe corner area, and the distance between the intersection point a and the intersection point b is the distance difference R.

As an example, the included angle between the line segment and the line pattern S1 with the lobe angle and the vertical line Y of the corresponding first simulation pattern S2 forming one line edge of the lobe angle may be specifically a second angle, where the range of the second angle is 30 ° to 60 °, and the value of the second angle is preferably 45 °, that is, the line segment coincides with the angular bisector of the right-angle lobe angle of the line pattern S1 as shown in fig. 4, and then the intersection point a of the line segment and the line pattern S1 coincides with the vertex of the right-angle corner thereof.

After determining the distance difference R between each of the line patterns with the lobe corners and the lobe corners included in the first simulation pattern corresponding to the line patterns, the line patterns (original patterns) with the distance difference R greater than the preset threshold value may be screened out, and then the lobe corners with the distance difference R greater than the preset threshold value (because one line pattern may include a plurality of lobe corners) may be found out from the screened line patterns, and corner processing may be performed on the lobe corners, so as to modify the shape of the lobe corner from a right angle to a target shape, where the target shape is other corner shapes with low probability of corner rounding effect and even difficult occurrence of corner rounding effect.

In the embodiment of the present invention, two methods of performing the rotation angle processing on the lobe rotation angle screened based on the determined distance difference R are specifically provided, and the description thereof will be provided below.

In a first mode, the embodiment of the present invention provides a specific implementation manner of performing corner processing on a lobe corner of a line graph (original graph) with a distance difference R greater than a preset threshold, where the method includes the following steps:

And S203.4a, carrying out corner cutting treatment on the convex corner of the original graph to obtain a corner cutting opening.

And step S203.5a, adding a rectangular correction pattern at the corner cutting opening so as to enable the shape of the corner of the convex angle to be adjusted from a right angle to a convex shape, wherein the middle point of the outer side edge of the rectangular correction pattern or the convex shape coincides with the vertex of the corner of the convex angle of the original pattern, and the outer side edge of the rectangular correction pattern or the convex shape is parallel to the corner cutting opening side edge of the original pattern.

In a second mode, another specific implementation manner of performing corner processing on the lobe corners of the line graph (original graph) with the distance difference R greater than a preset threshold is provided in the embodiment of the present invention, including the following steps:

And step S203.4b, performing outward edge expansion treatment on the vertex of the convex corner of the original graph so as to adjust the shape of the convex corner from a right angle to a convex shape, wherein the middle point of the outer side edge of the convex shape coincides with the vertex of the convex corner of the original graph, and the outer side edge of the convex shape is perpendicular to a line segment passing through the center of the original graph and the vertex of the convex corner before adjustment.

The value range of the outer side edge of the "convex" shape or the outer side edge of the rectangular correction pattern obtained after the adjustment can be either: 1/2R-5R, namely the length or the width of the rectangular structure with the protruding upper half part of the 'convex' structure can be 1/2R-5R, and the value ranges of the two can be different or the same.

Further, in the embodiment of the present invention, after adjusting the shape of the lobe corner of the original graphic from a right angle to a "convex" shape in step S203 of the OPC correction method shown in fig. 2, the OPC correction method may further include:

And S204, performing a second OPC correction on the original graph to obtain a second simulation graph of the original graph.

Step S205, determining a distance difference R 'between the convex corners of the original pattern and the second simulation pattern corresponding to the original pattern, where the distance difference R' represents a pattern difference between the plurality of line patterns on the mask and the second simulation pattern corresponding to the line patterns at the convex corners.

Step S206, if the distance difference R 'is greater than the preset threshold, adjusting the outer side edge of the "convex" shape or the outer side edge of the rectangular correction pattern, and returning to the step of executing the step S204 to perform the second OPC correction on the original pattern, so as to obtain a second simulation pattern of the original pattern, until the distance difference R' is less than the preset threshold.

In this embodiment, after the shape of the lobe corner on the line pattern is adjusted from the right angle to the "convex" shape by using the above steps S201 to S203, the steps of OPC correction, determining the distance difference R' and the like are performed again on the mask including the lobe corner shape and the adjusted line pattern, and then the distance difference R of each lobe corner on the mask is further made smaller than the preset threshold value by adjusting the length or width of the outer side of the "convex" shape of the lobe corner after the shape change or the outer side of the rectangular correction pattern multiple times, so as to meet the design requirement.

The specific process of the corner processing according to the present invention will be described below by taking the line graph with the lobe corners shown in fig. 3 as an example with reference to fig. 4 to 6.

For example, assuming that the line pattern on the mask plate to be subjected to the corner processing is an inverted "L" shape pattern as shown in fig. 3, the corner of the lobe corner of the line pattern is a right angle, and the process of performing the corner processing on the line pattern may specifically be: firstly cutting off a part of the right angle along the direction perpendicular to the angular bisector of the right angle to obtain a corner cutting opening, and then adding a rectangular correction pattern of W1 x W2 at the corner cutting opening, wherein one side (W2) of the rectangular correction pattern of W1 x W2 is the same as the width of the corner cutting opening, so that the shape of the corner of the convex angle added with the rectangular correction pattern is changed into a convex shape from the right angle, as shown in fig. 5.

Fig. 5 is a partial layout contrast diagram before and after the corner cutting process is performed on the lobe corner of the line pattern shown in fig. 3 by using the OPC correction method shown in fig. 2, that is, the pattern S1 in fig. 5 is an original shape of the line pattern on the mask, and the pattern S3 in fig. 5 is a layout pattern obtained by processing the right-angle corner of S1. For visual observation, the graph S3 in fig. 5 is shown separately in fig. 6 in the embodiment of the present invention.

Obviously, when the midpoint of the edge W1 of the convex shape, which is the same as the width of the corner cut opening, is overlapped with the right-angle vertex before the line pattern on the mask plate is re-corrected, the probability of corner rounding effect of the corner of the line pattern after corner processing is the lowest.

Therefore, after the OPC correction method provided by the embodiment of the invention is used for correcting the metal line layer or the line pattern with the lobe corner, the corner pattern of the line pattern is not a right angle, but is a convex shape protruding outwards, so that the probability of corner rounding effect of the line pattern with the lobe corner on the metal layer is effectively reduced by using the realization of other convex shapes with low probability of corner rounding effect, namely, the metal line structure formed on an actual silicon wafer by using the corrected mask meets the design requirement, the overlapping area of the formed metal layer structure and the formed through hole layer structure on the upper layer and the lower layer is increased, and the aim of improving the product yield of a semiconductor device is finally realized.

Based on the OPC correction method as described above, there is also provided an OPC correction system in this embodiment, which may include:

the original pattern acquisition module is used for acquiring a plurality of original patterns on the mask, wherein the original patterns are line patterns with convex corners for forming a metal layer on a wafer.

And the OPC correction module is used for carrying out first OPC correction and photoetching simulation on the plurality of original patterns on the mask plate so as to obtain a first simulation pattern of each original pattern.

The corner processing module is used for determining a distance difference R between each original graph and the lobe corners contained in the corresponding first simulation graph, and performing corner processing on the original graph with the distance difference R larger than a preset threshold value so as to modify the shape of the lobe corners of the original graph into a target shape.

The lobe corner is an angle equal to a first angle between two adjacent line edges in the line graph, and the first angle is 90 degrees.

Further, the corner processing module further includes:

And the overlapping unit is used for overlapping the original graph and the corresponding first simulation graph.

And the distance difference R determining unit is used for taking the center of the overlapped original graph and the corresponding first simulation graph as a starting point, making a line segment in the corner direction of the convex angle of the original graph or the first simulation graph, enabling the line segment and the line edges on the original graph and the corresponding first simulation graph forming the corner of the respective convex angle to form an intersection point respectively, and taking the distance between the two intersection points as the distance difference R.

The included angle between the line segment and the vertical line of one line edge of the lobe corner of the original graph or the corresponding first simulation graph is a second angle, and the range of the second angle is 30-60 degrees.

Further, the corner processing module further includes:

And the cutting unit is used for carrying out corner cutting treatment on the lobe corners of the original graph to obtain a corner cutting opening.

The first shape adjusting unit is used for adding a rectangular correction pattern at the corner cutting opening so as to adjust the shape of the corner of the convex angle from a right angle to a convex shape, wherein the middle point of the outer side edge of the rectangular correction pattern or the convex shape coincides with the vertex of the corner of the convex angle of the original pattern, and the outer side edge of the rectangular correction pattern or the convex shape is parallel to the corner cutting opening side edge of the original pattern.

Or the rotation angle processing module may further include:

And the second shape adjusting unit is used for carrying out outward edge expansion treatment on the top of the convex corner of the original graph so as to adjust the shape of the convex corner from a right angle to a convex shape, wherein the middle point of the outer side edge of the convex shape coincides with the top of the convex corner of the original graph, and the outer side edge of the convex shape is perpendicular to a line segment passing through the center of the original graph and the top of the convex corner of the original graph before adjustment.

The value range of the outer side edge of the convex shape or the outer side edge of the rectangular correction graph is as follows: 1/2R to 5R.

Based on the OPC correction method described above, the embodiment of the present invention further provides a mask, where the mask is specifically manufactured by using the mask plate making pattern obtained by the OPC correction method described above, that is, the mask provided in the embodiment of the present invention may include a line pattern for forming a metal layer on a wafer, where the corner of the lobe of the line pattern is not a right angle, but is a "convex" shape as shown in fig. 5.

In summary, in the OPC correction method provided by the present invention, after obtaining a plurality of line patterns with lobe corners for forming a metal layer on a wafer on a mask, conventional OPC correction and lithography simulation are performed on the line patterns, and then a distance difference R between each of the original patterns and the lobe corners included in the corresponding first simulation pattern is determined, and corner processing is performed on the original pattern with the distance difference R greater than a preset threshold value, so as to modify the shape of the lobe corner of the original pattern into a target shape, so as to obtain unexpected effects: the novel corner structure is used for improving the line pattern correction result of the metal layer on the mask plate in the OPC correction method, and the novel corner structure is used for directly adjusting the shape of the salient corner of the line pattern on the mask plate from a right angle which is easy to generate a corner rounding effect to other shapes (novel corner structure) which are difficult to generate the corner rounding effect in the OPC correction process of the line pattern with the salient corner on the metal layer or the through hole layer, so that the probability of generating the corner rounding effect of the line pattern with the salient corner on the metal layer is effectively reduced, namely the metal line structure formed on an actual silicon wafer by utilizing the corrected mask plate is ensured to meet the design requirement, the overlapping area of the formed metal layer structure and the formed through hole layer structure on the upper layer and the lower layer is increased, and the aim of improving the product yield of a semiconductor device is finally realized.

The embodiment of the invention also provides an electronic device, which comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory are communicated with each other through the communication bus,

A memory for storing a computer program;

And the processor is used for realizing the OPC correction method provided by the embodiment of the invention when executing the program stored in the memory.

In addition, other implementations of the OPC correction method implemented by the processor executing the program stored in the memory are the same as those mentioned in the foregoing method embodiment, and will not be described herein again.

The communication bus mentioned by the control terminal may be a peripheral component interconnect standard (PERIPHERAL COMPONENT INTERCONNECT, PCI) bus or an extended industry standard architecture (Extended Industry Standard Architecture, EISA) bus, etc. The communication bus may be classified as an address bus, a data bus, a control bus, or the like. For ease of illustration, the figures are shown with only one bold line, but not with only one bus or one type of bus.

The communication interface is used for communication between the electronic device and other devices.

The Memory may include random access Memory (Random Access Memory, RAM) or may include Non-Volatile Memory (NVM), such as at least one disk Memory. Optionally, the memory may also be at least one memory device located remotely from the aforementioned processor.

The processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; but may also be a digital signal processor (DIGITAL SIGNAL Processing, DSP), application SPECIFIC INTEGRATED Circuit (ASIC), field-Programmable gate array (Field-Programmable GATE ARRAY, FPGA) or other Programmable logic device, discrete gate or transistor logic device, discrete hardware components.

In yet another embodiment of the present invention, a computer readable storage medium is provided, in which instructions are stored, which when run on a computer, cause the computer to perform the OPC correction method of any of the above embodiments.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present invention, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk Solid STATE DISK (SSD)), etc.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

In this specification, each embodiment is described in a related manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for apparatus, electronic devices, and computer-readable storage medium embodiments, the description is relatively simple, as it is substantially similar to method embodiments, with reference to portions of the description of method embodiments being relevant.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. An OPC correction method, comprising:

Obtaining a plurality of original patterns on a mask, wherein the original patterns are line patterns with convex corners for forming a metal layer on a wafer;

performing first OPC correction and photoetching simulation on the plurality of original patterns on the mask plate to obtain a first simulation pattern of each original pattern;

Determining a distance difference R between each original pattern and a convex corner included in a first simulation pattern corresponding to the original pattern, performing corner cutting treatment on the convex corner of the original pattern with the distance difference R larger than a preset threshold value to obtain a corner cutting opening, and adding a rectangular correction pattern at the corner cutting opening to enable the shape of the convex corner to be adjusted from a right angle to a convex shape; the midpoint of the outer side edge of the rectangular correction pattern or the convex shape coincides with the vertex of the convex corner of the original pattern, and the outer side edge of the rectangular correction pattern or the convex shape is parallel to the corner cut opening side edge of the original pattern.

2. The OPC correction method of claim 1 wherein the lobe rotation angle is an angle equal to a first angle between two adjacent line edges in the line pattern, the first angle being 90 °.

3. The OPC correction method of claim 1 wherein at least one auxiliary pattern is added in the peripheral area of the line pattern according to a predetermined auxiliary pattern addition rule before performing the first OPC correction on the plurality of original patterns on the reticle.

4. The OPC correction method of claim 1 wherein the step of determining the distance difference R between the lobe corners contained in each of the original patterns and the corresponding first dummy patterns comprises:

overlapping the original graph and the corresponding first simulation graph;

Taking the center of the overlapped original graph and the corresponding first simulation graph as a starting point, making a line segment in the corner direction of the convex angle of the original graph or the first simulation graph, and enabling the line segment and the line edges on the original graph and the corresponding first simulation graph forming the corner of the respective convex angle to form an intersection point respectively;

5. The OPC correction method of claim 4 wherein the angle between the line segment and a vertical line of one line side of the lobe corner of the original pattern or the corresponding first dummy pattern is a second angle, and the second angle ranges from 30 ° to 60 °.

6. The OPC correction method of claim 1 wherein the outer side of the "convex" shape or the outer side of the rectangular correction pattern has a range of values: 1/2R to 5R.

7. The OPC correction method of claim 1 wherein the step of performing a first OPC correction on the plurality of original patterns on the reticle comprises:

And carrying out outward edge expansion treatment or inward edge contraction treatment on each line edge of the original graph along the direction perpendicular to the line edge.

8. The OPC correction method of claim 1 wherein after adjusting the shape of the lobe corners of the original pattern from right angles to "convex" shapes, the OPC correction method further comprises:

9. An OPC correction method, comprising:

Determining a distance difference R between each original graph and a convex corner included in a first simulation graph corresponding to the original graph, and performing outward edge expansion treatment on the vertex of the convex corner of the original graph, where the distance difference R is larger than a preset threshold value, so that the shape of the convex corner is adjusted from a right angle to a convex shape; the midpoint of the outer side edge of the convex shape coincides with the vertex of the convex corner of the original graph, and the outer side edge of the convex shape is perpendicular to a line segment passing through the center of the original graph and the vertex of the convex corner before adjustment.