Optical proximity correction method and layout processing equipment

Abstract

The present invention belongs to the field of microelectronics technology and relates to an optical proximity correction method and a layout processing device; by converting a virtual pattern into an environmental parameter, the amount of calculation of the optical proximity correction is reduced, thereby improving the efficiency of model solving; in combination with an SRAF graphic, the method of the present invention can improve the resolution and efficiency of the optical proximity correction for feature graphic transfer; wherein the solution time of the model is reduced to less than half of that of the existing method.

Description

Technical Field

[0001] The invention belongs to the field of microelectronic technology, and in particular relates to an optical proximity correction method and layout processing equipment. Background Art

[0002] Dummy pattern DP (Dummy Pattern) is often used in the optical proximity correction OPC (Optical Proximity Correction) process; usually, DP is inserted into the main pattern MP (Main Patter); then, OPC correction is performed on DP and MP together. Based on this, the processing of the above OPC process requires too much CPU (Central Processing Unit) time, which often fails to meet resource and efficiency requirements. Summary of the invention

[0003] The present invention discloses an optical proximity correction method, which converts a virtual pattern into an environmental parameter, so that the amount of optical proximity correction calculation is reduced and the efficiency of model solving is improved; combined with SRAF graphics, the resolution and efficiency of optical proximity correction for feature pattern transfer are also improved; wherein the solution time of the model is reduced to less than half of that of the existing method.

[0004] The method includes a data collection step, an environmental protection step, an intermediate conversion step and a synthesis output step. The data collection step acquires a first characteristic pattern; the first characteristic pattern is the characteristic pattern data before optical proximity correction; and then acquires a second characteristic pattern, i.e., a virtual pattern, which is combined with the first characteristic pattern to be used for offline or online testing and / or simulation of the first optical proximity correction of the first characteristic pattern, and the first optical proximity correction data of the first characteristic pattern is used as a parameter for subsequent correction of the first characteristic pattern.

[0005] Furthermore, by acquiring a first environmental vector; obtaining an initial condition of the correction process; the first environmental vector is a collection of environmental factors related to the first characteristic pattern and the optical proximity correction, used to provide a reference, give an initial value, a parameter sequence and / or a parameter value in the optical proximity correction.

[0006] The environmental protection step extracts a first sample pattern; wherein the first sample pattern is a partial pattern of a preset proportion of the second characteristic pattern in the second characteristic pattern.

[0007] The intermediate conversion step obtains a third graphic; wherein the third graphic is obtained by correcting the first sample graphic using an optical correction model.

[0008] The synthesis output step obtains a second environment vector, wherein the second environment vector is used to correct the first environment vector; and the second environment vector is used as a preset value to perform a second optical proximity correction on the first characteristic pattern.

[0009] Furthermore, the first characteristic pattern includes a characteristic pattern that needs to be transferred from the design layout to the surface of the workpiece; with the support of the second environment vector, a second optical proximity correction is performed on the first characteristic pattern.

[0010] The first characteristic pattern may include a characteristic pattern of grooves and / or holes with a depth-to-width ratio greater than 10.

[0011] Furthermore, the first characteristic pattern can be stored in a GDS or GDSII file; by reading the GDS or GDSII file and taking the second environment vector as a reference, the first characteristic pattern is corrected using a preset OPC model.

[0012] By acquiring a fourth characteristic pattern, wherein the fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; and using a preset OPC model to correct the fourth characteristic pattern.

[0013] Furthermore, the first environmental vector also includes line width and aperture parameters; the line width and aperture are modified based on the second environmental variable.

[0014] Corresponding to the method of the present invention, a layout processing device is also disclosed, including a data acquisition unit, an environment protection unit, an intermediate conversion unit and a synthesis output unit.

[0015] Wherein, the data acquisition unit acquires a first characteristic pattern; the first characteristic pattern is the characteristic pattern data before optical proximity correction; acquires a second characteristic pattern; wherein the second characteristic pattern is a virtual pattern, and the second characteristic pattern is combined with the first characteristic pattern for offline or online testing and / or simulation of the first optical proximity correction of the first characteristic pattern, and the first optical proximity correction data of the first characteristic pattern is used as a parameter for subsequent correction of the first characteristic pattern; acquires a first environmental vector; wherein the first environmental vector is a collection of environmental factors related to the first characteristic pattern and the optical proximity correction, and is used to provide a reference, give an initial value, a parameter sequence and / or a parameter value in the optical proximity correction.

[0016] Its environmental protection unit extracts a first sample figure; the first sample figure is a local figure of a second characteristic figure with a preset proportion in the second characteristic figure; the intermediate conversion unit obtains a third figure; the third figure is obtained by correcting the first sample figure through an optical correction model; the synthesis output step obtains a second environmental vector, and the second environmental vector is used to correct the first environmental vector; and the second optical proximity correction is performed on the first characteristic figure with the second environmental vector as a preset value.

[0017] Furthermore, the first feature pattern includes a feature pattern that needs to be transferred from the design layout to the workpiece surface; with the support of the second environment vector, a second optical proximity correction is performed on the first feature pattern; wherein the first feature pattern may include a feature pattern of grooves and / or holes with an aspect ratio greater than 10; the first feature pattern may be stored in a GDS or GDSII file.

[0018] By reading the GDS or GDSII file, taking the second environment vector as a reference, and using the preset OPC model to correct the first characteristic pattern.

[0019] Furthermore, by acquiring a fourth characteristic pattern, wherein the fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; the fourth characteristic pattern is corrected using a preset OPC model; wherein the first environmental vector may also include line width and aperture parameters; the line width and aperture are corrected based on the second environmental variable.

[0020] It should be noted that the terms "first", "second" and similar terms used in this article are only for describing the various components in the technical solution, and do not constitute a limitation of the technical solution, nor can they be understood as an indication or suggestion of the importance of the corresponding elements; elements with "first", "second" and similar terms indicate that the corresponding technical solution contains at least one of the element. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention and facilitate further understanding of the technical effects, technical features and purposes of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings. The accompanying drawings constitute an essential part of the specification and are used together with the embodiments of the present invention to illustrate the technical solution of the present invention, but do not constitute a limitation to the present invention.

[0022] The same reference numerals in the accompanying drawings represent the same components, specifically:

[0023] Figure 1 It is a schematic diagram of the processing flow of the virtual pattern by the OPC method in the prior art;

[0024] Figure 2 Schematic diagram of a process flow of processing a virtual pattern according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of a process flow of an embodiment of the method of the present invention;

[0026] Figure 4 It is a schematic diagram of the structure and information flow of the device embodiment of the present invention;

[0027] Figure 5 A schematic diagram showing the comparison between the processing time of the present invention and the prior art;

[0028] in:

[0029] 1-Layout requirements to be processed;

[0030] 2- Finished or semi-finished layout;

[0031] 3-Calculation time of the traditional approach (in seconds);

[0032] 4-Calculation time of the embodiment of the present invention (unit: seconds);

[0033] 10-data collection step, 11 data collection unit;

[0034] 20-Environmental protection steps, 22-Environmental protection units;

[0035] 30-intermediate conversion step, 33-intermediate conversion unit;

[0036] 40-synthetic output step, 44-synthetic output unit;

[0037] 100-first characteristic pattern;

[0038] 200-virtual pattern;

[0039] 300-OPC correction results;

[0040] 400 - Intermediate result after virtual pattern processing. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. Of course, the specific embodiments described below are only for explaining the technical solutions of the present invention, rather than for limiting the present invention. In addition, the parts described in the embodiments or the accompanying drawings are only examples of the relevant parts of the present invention, rather than the whole of the present invention.

[0042] like Figure 3 The flowchart of the embodiment of the method of the present invention is shown; it includes a data collection step 10, an environmental protection step 20, an intermediate conversion step 30 and a synthesis output step 40.

[0043] In the data acquisition step, the first characteristic pattern 100 and the characteristic pattern data before the optical proximity correction to be processed are obtained.

[0044] By acquiring a second characteristic pattern; wherein the second characteristic pattern is a virtual pattern, the second characteristic pattern is combined with the first characteristic pattern for offline or online testing and / or simulation of a first optical proximity correction of the first characteristic pattern, and the first optical proximity correction data of the first characteristic pattern is used as a parameter for subsequent correction of the first characteristic pattern.

[0045] By acquiring a first environment vector, wherein the first environment vector is a set of environment factors related to the first characteristic pattern and the optical proximity correction, and is used to provide a reference, an initial value, a parameter sequence and / or a parameter value in the optical proximity correction.

[0046] A first sample pattern is extracted through the environmental assurance step 20 ; wherein the first sample pattern is a partial pattern of the second characteristic pattern with a preset proportion in the second characteristic pattern.

[0047] The intermediate conversion step 30 obtains a third figure; wherein the third figure is obtained by correcting the first sample figure by an optical correction model.

[0048] The synthesis output step 40 obtains a second environment vector, wherein the second environment vector is used to correct the first environment vector; and the second optical proximity correction is performed on the first characteristic pattern with the second environment vector as a preset value.

[0049] Furthermore, the first characteristic pattern 100 may include a characteristic pattern that needs to be transferred from the design layout to the workpiece surface; with the support of the second environment vector, a second optical proximity correction 300 is performed on the first characteristic pattern.

[0050] Furthermore, the first characteristic pattern 100 may include a characteristic pattern of grooves and / or holes with an aspect ratio greater than 10; the first characteristic pattern 100 may be stored in a GDS or GDSII file; by reading the GDS or GDSII file, taking the second environment vector as a reference, the first characteristic pattern is corrected using a preset OPC model.

[0051] Furthermore, a fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; the fourth characteristic pattern may also be modified using a preset OPC model in order to obtain a larger process window.

[0052] Furthermore, the first environmental vector may also include line width and aperture parameters; the line width and aperture are modified based on the second environmental variable.

[0053] like Figure 4 , which is a schematic diagram of the structure and information flow of an embodiment of the device of the present invention, including a data acquisition unit 11, an environmental protection unit 22, an intermediate conversion unit 33, and a synthesis output unit 44; wherein:

[0054] The data acquisition unit 11 obtains a first characteristic pattern 100; the first characteristic pattern 100 is characteristic pattern data before optical proximity correction; obtains a second characteristic pattern; wherein the second characteristic pattern is a virtual pattern, and the second characteristic pattern is combined with the first characteristic pattern for offline or online testing and / or simulation of a first optical proximity correction of the first characteristic pattern, and the first optical proximity correction data of the first characteristic pattern is used as a parameter for subsequent correction of the first characteristic pattern; obtains a first environmental vector; wherein the first environmental vector is a collection of environmental factors related to the first characteristic pattern and the optical proximity correction, and is used to provide a reference, give an initial value, a parameter sequence and / or a parameter value in the optical proximity correction.

[0055] Furthermore, the environment protection unit 22 extracts a first sample pattern; the first sample pattern is a partial pattern of a preset proportion of the second characteristic pattern in the second characteristic pattern.

[0056] Furthermore, the intermediate conversion unit 33 obtains a third pattern, which may be obtained by correcting the first sample pattern using an optical correction model.

[0057] Furthermore, the synthesis output step 44 obtains a second environment vector for correcting the first environment vector; and performs a second optical proximity correction 300 on the first characteristic pattern with the second environment vector as a preset value.

[0058] The first feature pattern 100 includes a feature pattern that needs to be transferred from the design layout to the workpiece surface; with the support of the second environment vector, a second optical proximity correction 300 is performed on the first feature pattern; the first feature pattern 100 includes a feature pattern of grooves and / or holes with an aspect ratio greater than 10.

[0059] Furthermore, the first characteristic pattern 100 may be stored in a GDS or GDSII file; the GDS or GDSII file is read, and the first characteristic pattern is corrected using a preset OPC model with the second environment vector as a reference.

[0060] Further, a fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; and the fourth characteristic pattern is corrected using a preset OPC model. The first environment vector may also include line width and aperture parameters; and the line width and aperture are corrected based on the second environment variable.

[0061] like Figure 1 and Figure 2 As shown, the virtual pattern processing process 400 of the present invention goes through two stages: pre-OPC processing and OPC processing; Figure 5 Schematic diagram comparing the processing time of the present invention with that of the prior art; the present method does not perform OPC processing on the virtual pattern, thus shortening the OPC processing time.

[0062] It should be noted that the above embodiments are only for more clearly illustrating the technical solutions of the present invention. Those skilled in the art will understand that the implementation methods of the present invention are not limited to the above contents, and obvious changes, replacements or substitutions based on the above contents do not exceed the scope of the technical solutions of the present invention; other implementation methods will also fall within the scope of the present invention without departing from the concept of the present invention.

Claims

1. An optical proximity correction method, characterized in that The method comprises a data acquisition step (10): obtaining a first characteristic pattern (100); the first characteristic pattern (100) is characteristic pattern data before optical proximity correction; further obtaining a second characteristic pattern, the second characteristic pattern being a virtual pattern, the second characteristic pattern being combined with the first characteristic pattern for offline or online testing and / or simulation of a first optical proximity correction of the first characteristic pattern, the first optical proximity correction data of the first characteristic pattern being used as a parameter for subsequent correction of the first characteristic pattern; further obtaining a first environmental vector, the first environmental vector being a set of environmental factors related to the first characteristic pattern and the optical proximity correction, and being used to provide a reference, an initial value, a parameter sequence and / or a parameter value in the optical proximity correction; an environmental assurance step (20): extracting a first sample pattern; the first sample pattern being a local pattern of the second characteristic pattern with a preset proportion in the second characteristic pattern; An intermediate conversion step (30): obtaining a third graphic, the third graphic being obtained by correcting the first sample graphic using an optical correction model; a synthesis output step (40): obtaining a second environment vector, the second environment vector being used to correct the first environment vector; and performing a second optical proximity correction (300) on the first characteristic graphic using the second environment vector as a preset value; wherein the first characteristic graphic (100) comprises a characteristic graphic of a groove and / or a hole having an aspect ratio greater than 10.

2. The optical proximity correction method of claim 1, wherein: The first characteristic pattern (100) comprises a characteristic pattern that needs to be transferred from a design layout to a workpiece surface; and with the support of the second environment vector, a second optical proximity correction (300) is performed on the first characteristic pattern.

3. The optical proximity correction method according to claim 1 or 2, wherein: The first characteristic graphic (100) is stored in a GDS or GDSII file; the GDS or GDSII file is read, and the first characteristic graphic is corrected using a preset OPC model with the second environment vector as a reference.

4. The optical proximity correction method of claim 3, further comprising: Acquire a fourth characteristic pattern, wherein the fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; and modify the fourth characteristic pattern using the preset OPC model.

5. The optical proximity correction method of claim 4, wherein: The first environment vector also includes line width and aperture parameters; the line width and aperture are modified based on the second environment vector.

6. A layout processing device, comprising a data acquisition unit (11), an environment protection unit (22), an intermediate conversion unit (33), and a synthesis output unit (44); wherein: The data acquisition unit (11) acquires a first characteristic pattern (100); the first characteristic pattern (100) is characteristic pattern data before optical proximity correction; acquires a second characteristic pattern, the second characteristic pattern being a virtual pattern, the second characteristic pattern being combined with the first characteristic pattern for offline or online testing and / or simulation of a first optical proximity correction of the first characteristic pattern, the first optical proximity correction data of the first characteristic pattern being used as a parameter for subsequent correction of the first characteristic pattern; acquires a first environmental vector, the first environmental vector being a collection of environmental factors related to the first characteristic pattern and the optical proximity correction, and being used to provide a reference and an initial value in the optical proximity correction. , parameter sequence and / or parameter value; the environment assurance unit (22) extracts a first sample pattern; the first sample pattern is a local pattern of the second characteristic pattern with a preset proportion in the second characteristic pattern; the intermediate conversion unit (33) obtains a third pattern; the third pattern is obtained by correcting the first sample pattern with an optical correction model; the synthesis output unit (44) obtains a second environment vector, the second environment vector is used to correct the first environment vector; the second optical proximity correction (300) is performed on the first characteristic pattern with the second environment vector as a preset value, the first characteristic pattern (100) comprising a groove and / or hole characteristic pattern with a depth-to-width ratio greater than 10.

7. The layout processing device according to claim 6, wherein: The first characteristic pattern (100) comprises a characteristic pattern that needs to be transferred from a design layout to a workpiece surface; and with the support of the second environment vector, a second optical proximity correction (300) is performed on the first characteristic pattern.

8. The layout processing device according to claim 6 or 7, wherein: The first characteristic graphic (100) is stored in a GDS or GDSII file; the GDS or GDSII file is read, and the first characteristic graphic is corrected using a preset OPC model with the second environment vector as a reference.

9. The layout processing device according to claim 8, further comprising: Acquire a fourth characteristic pattern, wherein the fourth characteristic pattern is obtained by inserting the first characteristic pattern into the SRAF auxiliary pattern; and modify the fourth characteristic pattern using the preset OPC model.

10. The layout processing device according to claim 9, wherein: The first environment vector also includes line width and aperture parameters; the line width and aperture are modified based on the second environment vector.

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