A sub-resolution assist pattern layout method in OPC correction

Abstract

The application discloses an OPC correction sub-resolution auxiliary pattern layout method. A data acquisition module acquires a layout to be corrected by OPC; process windows of isolated patterns and dense patterns in the layout are calculated; SRAF initial rules are acquired, and SRAFs are inserted into the isolated patterns, and the SRAFs are exposed by a lithography model; SRAF widths are set according to SRAF exposure results; distances between the SRAFs and the isolated patterns are updated; and the SRAFs are inserted into the isolated patterns according to updated process parameters. According to a difference between a center position of a process window of the isolated patterns after the SRAFs are inserted and a center position of a process window of the dense patterns, adjustment of SRAF insertion parameters is realized, the SRAF insertion is suitable for isolated patterns of different sizes, is universal, can improve process windows of isolated patterns of various sizes, and finally improves product yield.

Description

A method for OPC-corrected sub-resolution auxiliary graphics layout Technical Field

[0001] This invention belongs to the field of integrated circuit lithography technology and relates to a sub-resolution auxiliary pattern layout method for OPC correction. Background Technology

[0002] In integrated circuit photolithography, only one photolithography condition is used to expose the photomask. However, the process windows (PW) differ for dense patterns and isolated patterns. If the same exposure conditions are used, it will be difficult for the photoresist dimensions of both dense and isolated patterns to meet expectations after exposure. During integrated circuit manufacturing, engineers primarily focus on the exposure results of dense patterns, therefore considering the optimal energy and depth of focus during exposure. To achieve good results for both dense and isolated patterns under the same exposure conditions, the current approach is to add sub-resolution auxiliary patterns (SRAFs) around the isolated patterns. These SRAFs are not displayed on the silicon wafer during exposure, but their addition increases the PW of the isolated patterns, resulting in a greater overlap between the PW of the isolated and dense patterns. This allows both dense and isolated patterns to achieve the target dimensions under the same exposure conditions.

[0003] Existing methods for inserting SRAFs are rule-based, primarily determining the number of SRAFs to insert based on the spacing between isolated figures. If the spacing between isolated figures is small, one SRAF is inserted; if the spacing is large, two SRAFs are inserted. This method can improve the power loss (PW) of isolated figures to some extent. However, since the spacing between SRAFs and figures, the width of the SRAFs, and the distance between SRAFs are all fixed, it cannot optimize the PW for all types of isolated figures.

[0004] Therefore, this invention provides a method for solving sub-resolution auxiliary pattern insertion rules by combining a lithography model with isolated patterns of different sizes to improve the lithography process window. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing an OPC-corrected sub-resolution auxiliary graphics layout method.

[0006] In a first aspect, the present invention provides a method for OPC-corrected sub-resolution auxiliary graphics layout, the method comprising the following steps:

[0007] S1: Obtain the layout to be corrected by OPC, expose the layout, and calculate the process window PW for isolated and dense graphics in the layout;

[0008] S2: Initialize the width d of the first-layer sub-resolution auxiliary graphic SRAF according to formulas (1) and (2). BW =d BW0 The position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM =d BtM0 And the position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM Satisfying the constraint MinSBWidth <d BW <1.2*MaxSBWidth; where MinSBWidth represents the minimum width specified during mask manufacturing, and MinSBWidth represents the minimum width of the sub-resolution auxiliary pattern SRAF that is exposed and developed.

[0009] d BW0 =MinSBWidth+10nm Equation (1)

[0010]

[0011] Where λ is the wavelength of the lithography machine, and k1 is a preset value, which is related to multiple physical parameters such as the numerical aperture, focal length, and energy threshold of the photoresist of the lithography machine.

[0012] According to the width d of the first-layer sub-resolution auxiliary graphic SRAF BW and position d BtM Insert the first-layer sub-resolution auxiliary graphic SRAF into the isolated graphic;

[0013] S3: Import the isolated pattern after inserting the sub-resolution auxiliary pattern SRAF into the photolithography model, simulate the exposure result of the isolated pattern on the wafer through the photolithography model, and check whether the inserted sub-resolution auxiliary pattern SRAF has been developed.

[0014] S4: If the sub-resolution auxiliary pattern SRAF develops, then update the width d of the sub-resolution auxiliary pattern SRAF according to formula (3). BW And according to the updated d BW Reinsert the sub-resolution auxiliary pattern SRAF into the isolated pattern and return to step S3, whereby the sub-resolution auxiliary pattern SRAF is again checked for development using the lithography model.

[0015] d BW =d BW -D1 Equation (3)

[0016] Where D1 represents the correction parameter.

[0017] S5: If the sub-resolution auxiliary pattern SRAF is not developed, continue to determine whether the center points of the dense pattern process window PW and the isolated pattern process window PW after inserting the sub-resolution auxiliary pattern SRAF coincide.

[0018] ISO PW ENERGY∈[DESEN PW ENERGY*α1,DENSE PW ENERGY*α2] Formula (4)

[0019] ISO PW FOCUS∈[DESEN PW FOCUS*β1,DESEN PW FOCUS*β2] Formula (5)

[0020] ISO PW ENERGY and ISO PW FOCUS refer to the energy and depth of focus corresponding to the center point of the isolated pattern process window after inserting the sub-resolution auxiliary pattern SRAF, respectively.

[0021] DESEN PW ENERGY and DENSE PW FOCUS refer to the energy and depth of focus corresponding to the center point of the dense graphics process window, respectively. β1 < α2, β1 < β2, and α1, α2, β1, and β2 are all preset weights.

[0022] S6: If the center points of the PW of the isolated graphic and the PW of the dense graphic coincide after inserting the sub-resolution auxiliary graphic SRAF, then the current sub-resolution auxiliary graphic SRAF layout scheme is considered to be the optimal scheme.

[0023] S7: If the center points of the PW of the isolated graphic and the PW of the dense graphic do not coincide after inserting the sub-resolution auxiliary graphic SRAF, then update the width d of the sub-resolution auxiliary graphic SRAF according to formula (6). BW Proceed to step S8;

[0024] d BW =d BW +ΔE*c Equation (6)

[0025] Where c represents the linear relationship between exposure energy and sub-resolution auxiliary pattern SRAF linewidth, and ΔE represents the difference between the center energy of isolated pattern process window PW and the center energy of dense pattern process window PW.

[0026] S8: Determine the width d of the updated subresolution auxiliary graphic SRAF. BW Does it satisfy the constraint condition of equation (7)?

[0027] MinSBWidth <d BW <1.2*MaxSBWidth Equation (7)

[0028] If satisfied, proceed to step S10;

[0029] If it is less than or equal to MinSBWidth, then the sub-resolution auxiliary graphic SRAF width d will be updated. BW =MaxSBWidth, then execute step S10;

[0030] If it is greater than or equal to 1.2*MaxSBWidth, then add a second sub-resolution auxiliary graphic SRAF, and calculate the distance d between the second sub-resolution auxiliary graphic SRAF and the first sub-resolution auxiliary graphic SRAF according to formula (8). BtB Since the second-layer sub-resolution auxiliary graphic SRAF and the first-layer sub-resolution auxiliary graphic SRAF have the same width, the width of the sub-resolution auxiliary graphic SRAF is updated according to formula (9), and the constraint condition of the width of the sub-resolution auxiliary graphic SRAF is updated to formula (10), and then step S9 is executed.

[0031] d BtB =d BtM -D2 Equation (8)

[0032] Where D2 represents the correction parameter;

[0033] d BW =d BW +θ*ΔE*c Equation (9)

[0034] Where θ is the preset correction value;

[0035] S9: Determine the width d of the updated subresolution auxiliary graphic SRAF. BW Does it satisfy the constraint condition formula (10)?

[0036] MinSBWidth <d BW <0.72*MaxSBWidth Equation (10)

[0037] If yes, proceed to step S10; otherwise, update the width of the sub-resolution auxiliary graphic SRAF according to formula (11).

[0038] d BW =m*0.72*MaxSBWidth Equation (11)

[0039] m represents a preset value, 0 < m < 1, and then step S10 is executed;

[0040] S10: Update the distance d between the first-layer sub-resolution auxiliary graphic SRAF and the isolated graphic according to formula (12). BtM Then proceed to step S11;

[0041] d BtM =ΔF 2*a+ΔF*b+d BtM Equation (12)

[0042] Where ΔF represents the difference between the center focal depth of the isolated graphic process window PW and the center focal depth of the dense graphic process window PW after inserting the sub-resolution auxiliary graphic SRAF; a and b both represent the correction preset values.

[0043] S11: Based on the updated process parameters d BW d BtB d BtM Insert the sub-resolution auxiliary graphic SRAF into the isolated graphic, and then return to step S3.

[0044] Secondly, the present invention provides a mask, which is obtained by using the method to perform sub-resolution auxiliary graphic layout and then modifying it.

[0045] Thirdly, the present invention provides a device for correcting a photomask pattern, comprising:

[0046] The data acquisition module acquires the layout to be corrected by OPC.

[0047] The calculation module is used to calculate the process windows (PW) of isolated and dense graphics in the layout.

[0048] The lithography exposure detection module is used to obtain the initial rules of SRAF, insert SRAF into isolated patterns, and expose SRAF through the lithography model;

[0049] The SRAF width update module sets the SRAF width based on the SRAF exposure results.

[0050] The SRAF position update module updates the distance between the sub-resolution auxiliary graphic SRAF and the isolated graphic.

[0051] The OPC correction module performs OPC corrections on the layout processed by the SRAF position update module in all directions where the manufacturability rules of each mask are not restricted.

[0052] Fourthly, the present invention provides a computer device including a memory, a modifier, and a computer program stored in the memory and executable on the modifier, wherein the modifier implements the steps of the method when executing the computer program.

[0053] Fifthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a modifier, implements the steps of the method.

[0054] The beneficial effects of this invention are:

[0055] This invention proposes adjusting the insertion parameters of the sub-resolution auxiliary pattern SRAF based on the difference between the center positions of the isolated pattern process window and the dense pattern process window after inserting the sub-resolution auxiliary pattern SRAF. This method is applicable to the insertion of sub-resolution auxiliary pattern SRAF for isolated patterns of different sizes, possessing universality and improving the process window for isolated patterns of various sizes, ultimately increasing product yield. Simultaneously, the sub-resolution auxiliary pattern SRAF can improve the overlap between the process windows of various sizes of isolated patterns and the dense pattern process windows, facilitating the determination of optimal energy and optimal depth of focus during photolithography, thereby improving chip yield and device performance. Attached Figure Description

[0056] Figure 1. Flowchart of the method of the present invention;

[0057] Figure 2. Dense pattern exposure results at different energies and depths of focus;

[0058] Figure 3. Isolated pattern exposure results at different energies and depths of focus;

[0059] Figure 4. The image after inserting the sub-resolution auxiliary graphic SRAF;

[0060] Figure 5. Measurement results and PW of isolated graphic after inserting sub-resolution auxiliary graphic SRAF. Detailed Implementation

[0061] The present invention will be further analyzed below with reference to specific embodiments and accompanying drawings.

[0062] An OPC-based sub-resolution auxiliary graphics layout method, as shown in Figure 1, includes the following steps:

[0063] S1: Obtain the layout to be corrected by OPC, expose the layout, and calculate the process window PW for isolated and dense graphics in the layout;

[0064] S2: Initialize the width d of the first-layer sub-resolution auxiliary graphic SRAF according to formulas (1) and (2). BW =d BW0 The position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM =d BtM0 And the position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM Satisfying the constraint MinSBWidth <d BW <1.2*MaxSBWidth; where MinSBWidth represents the minimum width specified during mask manufacturing, and MinSBWidth represents the minimum width of the sub-resolution auxiliary pattern SRAF that is exposed and developed.

[0065] d BW0=MinSBWidth+10nm Equation (1)

[0066]

[0067] Where λ is the wavelength of the lithography machine, and k1 is a preset value, which is related to multiple physical parameters such as the numerical aperture, focal length, and energy threshold of the photoresist of the lithography machine.

[0068] Since the measurement of MaxSBWidth through actual exposure focuses on the size at which all isolated graphic elements inserted into the sub-resolution auxiliary graphic SRAF will be exposed, this value represents the minimum value for exposure of the sub-resolution auxiliary graphic SRAF. Therefore, for some isolated graphics, their corresponding MaxSBWidth can be slightly larger. Thus, the width constraint of the sub-resolution auxiliary graphic SRAF is set to be slightly larger than MaxSBWidth. This is based on the width d of the first layer of sub-resolution auxiliary graphic SRAF. BW and position d BtM Insert the first-layer sub-resolution auxiliary graphic SRAF into the isolated graphic.

[0069] S3: Then, the isolated pattern after inserting the sub-resolution auxiliary pattern SRAF is imported into the photolithography model. The exposure result of the isolated pattern on the wafer is simulated by the photolithography model to check whether the inserted sub-resolution auxiliary pattern SRAF has been developed.

[0070] S4: If the sub-resolution auxiliary pattern SRAF develops, then update the width d of the sub-resolution auxiliary pattern SRAF according to formula (3). BW And according to the updated d BW Reinsert the sub-resolution auxiliary pattern SRAF into the isolated pattern and return to step S3, whereby the sub-resolution auxiliary pattern SRAF is again checked for development using the lithography model.

[0071] d BW =d BW -D1 Equation (3) where D1 represents the correction parameter, and in this embodiment, the value is 5nm.

[0072] S5: If the sub-resolution auxiliary pattern SRAF is not developed, continue to determine whether the center points of the dense pattern process window PW and the isolated pattern process window PW after inserting the sub-resolution auxiliary pattern SRAF coincide. Figure 2-3 shows the measurement results of the isolated pattern at a certain size and the dense pattern at the main size after photolithography exposure under different energy and depth of focus conditions. The gray areas are the corresponding process windows, and the boxes are their common process windows.

[0073] ISO PW ENERGY∈[DESEN PW ENERGY*α1,[DESEN PW ENERGY*α2] Formula (4)

[0074] ISO PW FOCUS∈[DESEN PW FOCUS*β1,[DESEN PW ENERGY*β2] Formula (5)

[0075] ISO PW ENERGY and ISO PW FOCUS refer to the energy and depth of focus corresponding to the center point of the isolated pattern process window after inserting the sub-resolution auxiliary pattern SRAF, respectively.

[0076] DESEN PW ENERGY and DENSE PW FOCUS refer to the energy and depth of focus corresponding to the center point of the dense pattern process window, respectively. α1 < α2, β1 < β2, and α1, α2, β1, and β2 are all preset weights.

[0077] S6: If the center points of the PW of the isolated graphic and the PW of the dense graphic coincide after inserting the sub-resolution auxiliary graphic SRAF, then the current sub-resolution auxiliary graphic SRAF layout scheme is considered to be the optimal scheme.

[0078] S7: If the center points of the PW of the isolated graphic and the PW of the dense graphic do not coincide after inserting the sub-resolution auxiliary graphic SRAF, then update the width d of the sub-resolution auxiliary graphic SRAF according to formula (6). BW Proceed to step S8;

[0079] d BW =d BW +ΔE*c Equation (6)

[0080] Where ΔE represents the difference between the center energy of the isolated patterned process window (PW) and the center energy of the dense patterned process window (PW); c represents the linear relationship between exposure energy and the sub-resolution auxiliary pattern (SRAF) linewidth. This value is the result obtained by fitting actual wafer measurement data.

[0081] S8: Determine the width d of the updated subresolution auxiliary graphic SRAF. BW Does it satisfy the constraint condition of equation (7)?

[0082] If satisfied, proceed to step S10;

[0083] If it is less than or equal to MinSBWidth, then the sub-resolution auxiliary graphic SRAF width d will be updated. BW =MinSBWidth, then proceed to step S10;

[0084] MinSBWidth <d BW<1.2*MaxSBWidth Equation (7)

[0085] If it is greater than or equal to 1.2*MaxSBWidth, then add a second sub-resolution auxiliary graphic SRAF, and calculate the distance d between the second sub-resolution auxiliary graphic SRAF and the first sub-resolution auxiliary graphic SRAF according to formula (8). BtB Since the second-layer sub-resolution auxiliary graphic SRAF and the first-layer sub-resolution auxiliary graphic SRAF have the same width, the width of the sub-resolution auxiliary graphic SRAF needs to be updated according to formula (9), and the constraint condition of the width of the sub-resolution auxiliary graphic SRAF needs to be updated to formula (10), and then step S9 is executed.

[0086] d BtB =d BtM -D2 Equation (8)

[0087] Where D2 represents the correction parameter, and in this embodiment, the value is 10nm.

[0088] d BW =d BW +θ*ΔE*c Equation (9)

[0089] Where θ is the preset correction value, which is 0.35 in this embodiment;

[0090] S9: Determine the width d of the updated subresolution auxiliary graphic SRAF. BW If the constraint condition formula (10) is satisfied, proceed to step S10; otherwise, update the width of the sub-resolution auxiliary graphic SRAF again according to formula (11).

[0091] MinSBWidth <d BW <0.72*MaxSBWidth Equation (10)

[0092] d BW =0.72*m*MaxSBWidth Equation (11)

[0093] m represents a preset value, 0 < m < 1, and then step S10 is executed;

[0094] S10: Update the distance d between the first-layer sub-resolution auxiliary graphic SRAF and the isolated graphic according to formula (12). BtM Then proceed to step S11;

[0095] d BtM =ΔF 2 *a+ΔF*b+d BtM Equation (12)

[0096] Where ΔF represents the difference between the center focal depth of the isolated pattern process window PW and the center focal depth of the dense pattern process window PW after inserting the sub-resolution auxiliary pattern SRAF; a and b both represent the correction preset values, which are obtained by different d BtM The changing graphs are measured on actual wafers, and the data relationship parameters are obtained by fitting the data.

[0097] S11: Based on the updated process parameters d BW d BtB d BtM Insert the sub-resolution auxiliary graphic SRAF into the isolated graphic, and then return to step S3.

[0098] As shown in the figure, the sub-resolution auxiliary pattern (SRAF) insertion rule for isolated patterns at this size, obtained through calculation, is as follows: the width of the sub-resolution auxiliary pattern (SRAF) is 43nm, the distance from the sub-resolution auxiliary pattern (SRAF) to the main pattern is 126nm, and the distance between the sub-resolution auxiliary patterns (SRAF) is 116nm. By inserting isolated patterns with this rule of sub-resolution auxiliary patterns (SRAF) through actual wafer exposure, the process window is shown in Figure 4. The process window of the isolated pattern with the inserted sub-resolution auxiliary pattern (SRAF) coincides with the process window of the dense pattern, as shown in the box in Figure 5. Therefore, this method for solving the sub-resolution auxiliary pattern insertion rule is considered effective.

Claims

1. A method for OPC-corrected sub-resolution auxiliary graphics layout, characterized in that... The method includes the following steps: S1: Obtain the layout to be corrected by OPC, expose the layout, and calculate the process window PW of isolated graphics and dense graphics in the layout; S2: Initialize the width d of the first layer sub-resolution auxiliary graphic SRAF according to formula (1) and formula (2). BW =d BW0 and the position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM =d BtM0 And the position d of the first-layer sub-resolution auxiliary graphic SRAF to the isolated graphic BtM Satisfying the constraint MinSBWidth<d BW <1.2*MaxSBWidth; where MinSBWidth represents the minimum width specified during mask manufacturing, and MaxSBWidth represents the minimum width of the sub-resolution auxiliary pattern SRAF that is exposed and developed; d BW0 =MinSBWidth+10hm Equation (1) Where λ is the wavelength of the lithography machine, and k1 is a preset value; according to the width d of the first sub-resolution auxiliary pattern SRAF. BW and position d BtM S3: Insert the first layer of sub-resolution auxiliary pattern SRAF into the isolated pattern; S4: Import the isolated pattern after inserting the sub-resolution auxiliary pattern SRAF into the photolithography model, simulate the exposure result of the isolated pattern on the wafer through the photolithography model, and check whether the inserted sub-resolution auxiliary pattern SRAF has developed; S5: If the sub-resolution auxiliary pattern SRAF has developed, update the width d of the sub-resolution auxiliary pattern SRAF according to formula (3). BW And according to the updated d BW Reinsert the subresolution auxiliary graphic SRAF into the isolated graphic and return to step S3; BW =d BW -D1 Equation (3) where D1 represents the correction parameter; S5: If the sub-resolution auxiliary pattern SRAF is not developed, then continue to determine whether the center points of the dense pattern process window PW and the isolated pattern process window PW after inserting the sub-resolution auxiliary pattern SRAF coincide; S6: If the center points of the isolated pattern PW and the dense pattern PW coincide after inserting the sub-resolution auxiliary pattern SRAF, then the current sub-resolution auxiliary pattern SRAF layout scheme is considered to be the optimal scheme; S7: If the center points of the isolated pattern PW and the dense pattern PW do not coincide after inserting the sub-resolution auxiliary pattern SRAF, then update the width d of the sub-resolution auxiliary pattern SRAF according to formula (6). BW Then execute step S8; BW =d BW +ΔE*c Equation (6) where c represents the linear relationship between exposure energy and sub-resolution auxiliary pattern SRAF linewidth, and ΔE represents the difference between the center energy of isolated pattern process window PW and the center energy of dense pattern process window PW; S8: Determine the width d of the updated sub-resolution auxiliary pattern SRAF. BW Does it satisfy the constraint condition of equation (7)? MinSBWidth < d BW If equation (7) is satisfied (<1.2*MaxSBWidth), then proceed to step S10; if it is less than or equal to MinSBWidth, then update the width d of the sub-resolution auxiliary graphic SRAF. BW =MinSBWidth, then execute step S10; if it is greater than or equal to 1.2*MaxSBWidth, then add the second sub-resolution auxiliary graphic SRAF, and calculate the distance d between the second sub-resolution auxiliary graphic SRAF and the first sub-resolution auxiliary graphic SRAF according to formula (8). BtB Since the second-layer sub-resolution auxiliary graphic SRAF has the same width as the first-layer sub-resolution auxiliary graphic SRAF, the width of the sub-resolution auxiliary graphic SRAF needs to be updated according to formula (9), and the constraint condition of the width of the sub-resolution auxiliary graphic SRAF needs to be updated to formula (10). Then, step S9 is executed. BtB =d BtM -D2 Equation (8) where D2 represents the correction parameter; d BW =d BW +θ*ΔE*c Equation (9) where θ is the preset value for correction; S9: Determine the width d of the updated sub-resolution auxiliary graphic SRAF. BW Does it satisfy the constraint formula (10), MinSBWidth<d? BW If the value of <0.72*MaxSBWidth (10) is true, then proceed to step S10; otherwise, update the width of the sub-resolution auxiliary graphic SRAF to d according to formula (11). BW =m*0.72*MaxSBWidth Equation (11) where m represents the preset value, 0<m<1, and then execute step S10; S10: Update the distance d between the first-layer sub-resolution auxiliary graphic SRAF and the isolated graphic according to formula (12). BtM Then proceed to step S11; BtM =ΔF 2 *a+ΔF*b+d BtM Equation (12) where ΔF represents the difference between the center focal depth of the isolated pattern process window PW and the center focal depth of the dense pattern process window PW after inserting the sub-resolution auxiliary pattern SRAF; a and b both represent the preset correction values; S11: based on the updated process parameters d BW d BtB d BtM Insert the sub-resolution auxiliary graphic SRAF into the isolated graphic, and then return to step S3.

2. The method according to claim 1, characterized in that... Before and after inserting the sub-resolution auxiliary graphic SRAF in step S6, the energy and depth of focus corresponding to the center point of the isolated graphic process window specifically satisfy: ISO PW ENERGY∈[DESEN PW ENERGY*α1, DENSE PW ENERGY*α2] Equation (4) ISO PWFOCUS∈[DESENPWFOCUS*β1, DENSEPWFOCUS*β2] Equation (5) where ISO PW ENERGY and ISO PW FOCUS refer to the energy and depth of focus corresponding to the center point of the isolated graphic process window after inserting the sub-resolution auxiliary graphic SRAF, respectively; DESEN PW ENERGY and DENSEPWFOCUS refer to the energy and depth of focus corresponding to the center point of the dense graphics process window, respectively. α1 < α2, β1 < β2, and α1, α2, β1, and β2 are all preset weights.

3. A photomask, characterized in that... The sub-resolution auxiliary graphic layout is performed using the method described in any one of claims 1 to 2, and then modified accordingly.

4. A device for correcting a photomask pattern, characterized in that, include: The data acquisition module acquires the layout to be corrected by OPC. The calculation module is used to calculate the process windows (PW) of isolated and dense graphics in the layout. The lithography exposure detection module is used to obtain the initial rules of SRAF, insert SRAF into the isolated pattern, and expose SRAF through the lithography model; the SRAF width update module sets the SRAF width according to the SRAF exposure result; the SRAF position update module updates the distance between the sub-resolution auxiliary pattern SRAF and the isolated pattern. The OPC correction module performs OPC corrections on the layout processed by the SRAF position update module in all directions where the manufacturability rules of each mask are not restricted.

5. A computer device comprising a memory, a modifier, and a computer program stored in the memory and executable on the modifier, characterized in that, When the corrector executes the computer program, it implements the steps of the method as claimed in any one of claims 1 to 2.

6. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the corrector, it implements the steps of the method as described in any one of claims 1 to 2.

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