Method for measuring photoresist erosion and optical proximity correction method
By setting anchor points on the photoresist layer and measuring the distance between the actual edge of the photoresist pattern and the target edge, the problem of accurate measurement of the photoresist retreat amount is solved, and the pattern accuracy and product yield of the photolithography process are improved.
Patent Information
- Application Number
- CN202411085436.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-08
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2044-08-08
AI Technical Summary
It is difficult to accurately measure the amount of photoresist degradation in photoresist patterns using existing technologies, which leads to pattern distortion in the photolithography process and affects the performance of integrated circuits.
Anchor points are set on the photoresist layer, and the distance between the edge of the actual photoresist pattern and the target edge is measured to obtain the photoresist recession amount.
Accurately measure photoresist retreat to improve optical proximity correction accuracy and enhance product yield.
Smart Images
Figure CN118838127B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of semiconductor integrated circuit design and manufacturing, and particularly relates to a photoresist recession amount measuring method and an optical proximity correction method. BACKGROUND
[0002] In the field of semiconductor manufacturing, especially in the photolithography process of integrated circuits (IC), optical proximity correction (OPC) technology is crucial for improving pattern resolution and manufacturing precision. With the continuous reduction of integrated circuit feature size, the optical diffraction effect in the photolithography process has an increasingly significant impact on pattern precision.
[0003] In the photolithography process, the line end of the photoresist material will shrink due to optical diffraction, which is known as "photoresist recession". Specifically, when light passes through the pattern on the photomask, due to diffraction and interference effects, light will shine on the photoresist material that should not be illuminated, causing the photoresist material in this part to be dissolved and removed during development, resulting in the shrinkage of the size of the photoresist material end. If the photoresist recession phenomenon is not properly handled, it will cause pattern distortion in subsequent etching and other process steps, thereby affecting the performance of the IC.
[0004] To solve the problem of photoresist recession, existing optical proximity correction techniques usually involve modifying the photomask pattern to compensate for pattern distortion caused by optical diffraction. The modification process requires a large amount of experimental data and simulation results, including photoresist recession data.
[0005] Currently, whether the widths of the pattern combinations are consistent or not, the total recession amount of the patterns on both sides is divided by two, so that a set of recession amount data can be quickly obtained, but in this way, the actual recession amount of the pattern combinations with inconsistent widths cannot be accurately obtained.
[0006] As shown in the upper pattern of FIG. 1, Figure 1 If the widths of the patterns 101 on both sides are equal, the recession amount remains consistent, the position of the theoretical pattern 102 can be accurately determined, and the correct recession amount D1 can be obtained by dividing the total recession amount by two.
[0007] However, as shown in the lower pattern of FIG. 1, Figure 1As shown in the lower graph, when the widths of the two graphs are inconsistent, generally, the fading amount of the larger-width graph 103 is smaller than that of the smaller-width graph 101, and the fading amounts of the two graphs are inconsistent. If the theoretical graph 105 of the larger-width graph 103 is deviated by dividing the total fading amount by two, only an inaccurate offset graph 104 can be obtained in calculation, and the position of the theoretical graph 105 cannot be accurately determined, an inaccurate fading amount D2 is obtained, and the actual fading amount D3 of the graph 103 cannot be obtained. Similarly, for the Figure 1 the lower graph, the actual fading amount of the graph 101 cannot be obtained.
[0008] It should be noted that the above introduction of the technical background is only for the convenience of clearly and completely describing the technical scheme of the present application, and facilitating the understanding of those skilled in the art. The above technical scheme cannot be considered as known to those skilled in the art only because it is described in the background section of the present application. SUMMARY
[0009] In view of the above-mentioned defects of the prior art, the purpose of the present application is to provide a photoresist fading amount measurement method and an optical proximity correction method, which are used to solve the problem that the photoresist fading amount of a graph is difficult to be obtained in the prior art.
[0010] To achieve the above-mentioned purpose and other related purposes, the present application provides a photoresist fading amount measurement method, which comprises the following steps: providing a photoresist layer, defining a target photoresist graph on the photoresist layer, and setting an anchor point on the target photoresist graph; exposing and developing the photoresist layer according to the defined target photoresist graph to form an actual photoresist graph with the anchor point; determining a target edge of the target photoresist graph based on the position of the anchor point of the actual photoresist graph; obtaining an actual edge of the actual photoresist graph by measurement; and obtaining a photoresist fading amount of the actual photoresist graph based on the spacing between the actual edge and the target edge.
[0011] Optionally, the actual photoresist graph comprises a plurality of first photoresist units arranged in a column direction, wherein the target edge of a to-be-measured first photoresist unit is obtained based on the position of the anchor point, the actual edge of the to-be-measured first photoresist unit is obtained by measurement, and the photoresist fading amount of the to-be-measured first photoresist unit is obtained based on the spacing between the actual edge and the target edge.
[0012] Optionally, the anchor point comprises a protruding structure arranged on one or more side edges of the first photoresist unit or a connecting bridge structure connected between two adjacent first photoresist units.
[0013] Optionally, the distance between the two adjacent first photoresist units is greater than 2 times the minimum feature size of the current process, the anchor point is a protruding structure arranged at the side of the first photoresist unit, and the height and width of the protruding structure are both set as the minimum feature size of the current process.
[0014] Optionally, the distance between the two adjacent first photoresist units is less than or equal to 2 times the minimum feature size of the current process, the anchor point is a connecting bridge structure connected between the two adjacent first photoresist units, and the width of the connecting bridge structure is set as the minimum feature size of the current process.
[0015] Optionally, the first photoresist unit provided with the anchor point is a non-measured first photoresist unit, and the non-measured first photoresist unit and the measured first photoresist unit are two different first photoresist units.
[0016] Optionally, the distance between the anchor point and the target edge is greater than the photoresist recession amount of the actual photoresist pattern.
[0017] Optionally, the distance between the anchor point and the target edge is 400-500 nm.
[0018] Optionally, the actual photoresist pattern further includes a plurality of second photoresist units arranged opposite to the first photoresist units in the row direction, and the measuring method further includes: obtaining the target edge of a measured second photoresist unit based on the anchor point position.
[0019] The actual edge of the measured second photoresist unit is obtained by measurement, and the photoresist recession amount of the measured second photoresist unit is obtained based on the distance between the actual edge and the target edge of the measured second photoresist unit.
[0020] Optionally, the measured second photoresist unit has a different pattern width from the measured first photoresist unit.
[0021] Optionally, the plurality of first photoresist units and the plurality of second photoresist units are arranged in alignment or misalignment.
[0022] As described above, the photoresist recession amount measuring method and the optical proximity correction method of the present application have the following beneficial effects:
[0023] The present application sets an anchor point in the lithography pattern as a positioning basis, and the accurate target edge of the photoresist pattern can be obtained based on the anchor point. After the actual edge of the photoresist pattern is obtained by measurement, the photoresist recession amount of the photoresist pattern can be obtained through the distance between the actual edge and the target edge, i.e. the change amount of each photoresist line end pattern can be accurately obtained.
[0024] After the accurate photoresist recession amount is obtained, the simulation correction pattern can be obtained from the optical proximity correction model through the photoresist recession amount, which can be used for actual mass production, and the product yield can be greatly improved. BRIEF DESCRIPTION OF DRAWINGS
[0025] The accompanying drawings are included to provide a further understanding of embodiments of the application, and are incorporated in and constitute a part of this specification, illustrate embodiments of the application, and together with the description serve to explain the principles of the application. It is to be understood that other embodiments can be utilized, and structural and functional modifications can be made without departing from the scope of the present application.
[0026] Figure 1 A schematic diagram of a test principle of a test method for showing a photoresist loss amount in the art.
[0027] Figures 2 to 5 A schematic diagram of structures of several different photoresist patterns for showing a photoresist loss amount measurement method of embodiments of the application.
[0028] Figure 6 A schematic diagram of a test principle of a test method for showing a photoresist loss amount measurement method of embodiments of the application.
[0029] ELEMENT REFERENCE
[0030] 20 first photoresist column
[0031] 201 non-test first photoresist unit
[0032] 202 connection bridge structure
[0033] 203 protruding structure
[0034] 204, 205 test first photoresist unit
[0035] 206 target edge of test first photoresist unit
[0036] 30 second photoresist column
[0037] 301 test second photoresist unit
[0038] 302 target edge of test second photoresist unit DETAILED DESCRIPTION
[0039] The forgoing detailed description of the application has been presented for the purposes of elucidation and will not limit the application as construed in the broadest possible terms. It is intended that the scope of the application be determined only by reference to the claims.
[0040] It should be emphasized that the term "comprises / comprising" when used in this specification is taken to mean the presence of stated features, integers, steps or components but not to the exclusion of one or more other features, integers, steps, components or groups thereof.
[0041] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.
[0042] For example, when describing the embodiments of the present invention, cross-sectional views of device structures may be partially enlarged to scale for ease of explanation. Furthermore, these schematic views are merely illustrative and should not limit the scope of the present invention. Furthermore, in actual manufacturing, three-dimensional dimensions, including length, width, and depth, should be included.
[0043] For convenience, spatially relative terms such as "under," "below," "below," "below," "above," and "on" may be used herein to describe the relationship of one element or feature to other elements or features shown in the drawings. It will be understood that these spatially relative terms are intended to encompass orientations of the device in use or operation in addition to the orientation depicted in the drawings. Additionally, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.
[0044] In the context of the present application, a structure described as a first feature being "above" a second feature may include embodiments where the first and second features are formed in direct contact, and may also include embodiments where an additional feature is formed between the first and second features, such that the first and second features may not be in direct contact.
[0045] It should be noted that the illustrations provided in this embodiment are only used to schematically illustrate the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.
[0046] like Figures 2 to 6 As shown, this embodiment provides a method for measuring the amount of photoresist degradation, the measuring method comprising:
[0047] In step 1), a photoresist layer is provided, a target photoresist pattern is defined on the photoresist layer, and anchor points are set on the target photoresist pattern.
[0048] In step 2), the photoresist layer is exposed and developed according to the defined target photoresist pattern to form an actual photoresist pattern with anchor points.
[0049] Step 3) determining a target edge of the target photoresist pattern based on the anchor point position of the actual photoresist pattern.
[0050] Step 4), obtaining the actual edge of the actual photoresist pattern by measurement.
[0051] Step 5) Based on the distance between the actual edge and the target edge, the photoresist retreat amount of the actual photoresist pattern is obtained.
[0052] like Figure 2 As shown, in one embodiment, the actual photoresist pattern includes a first photoresist column 20 and a second photoresist column 30. The first photoresist column 20 includes a plurality of first photoresist units spaced apart in the column direction. The second photoresist column 30 includes a plurality of second photoresist units arranged opposite to the first photoresist units in the row direction. The first photoresist units and the second photoresist units are aligned. The spacing between two adjacent first photoresist units is less than or equal to 2 times the minimum feature size of the current process. The anchor point is set as a connecting bridge structure 202 connecting two adjacent first photoresist units. The width of the connecting bridge structure 202 is preferably set to the minimum feature size of the current process to save space. The first photoresist unit with the anchor point is a non-test first photoresist unit 201. The non-test first photoresist unit 201 and the test first photoresist unit 204 are two different first photoresist units, as shown in FIG. Figure 2 As shown, the first photoresist units used to measure the actual edge are the first photoresist units 204 to be measured on both sides of the "+" sign and the second photoresist unit 301 to be measured opposite to the first photoresist unit 204 in the row direction. The anchor point is set on another first photoresist unit 201 not to be measured that is different from the first photoresist unit 204 to be measured. The distance between the anchor point and the target edge of the first photoresist unit 201 not to be measured is usually set to be greater than the light resistance reduction amount of the first photoresist unit 201 not to be measured. For example, the distance between the anchor point and the target edge of the first photoresist unit 201 not to be measured is preferably 400 nanometers to 500 nanometers, such as 450 nanometers. During actual measurement, it is preferred to set the "+" sign in the figure at the center of the optical measurement, and during optical measurement, set the anchor point within the optical measurement range. The optical measurement range is, for example, Figure 2 It should be noted that the widths of the first light blocking unit and the second light blocking unit may be equal or unequal, and are not limited to the example shown in the figure.
[0053] like Figure 3As shown, in one embodiment, the actual photoresist pattern includes a first photoresist column 20 and a second photoresist column 30, the first photoresist column 20 includes a plurality of first photoresist units arranged in a column direction with intervals, the second photoresist column 30 includes a plurality of second photoresist units arranged in a row direction opposite to the first photoresist units, a distance between two adjacent first photoresist units is less than or equal to 2 times of a minimum feature size of a current process, the anchor point is arranged on a connecting bridge structure 202 connecting between the two adjacent first photoresist units, and a width of the connecting bridge structure 202 is preferably set as the minimum feature size of the current process to save space. The first photoresist units and the second photoresist units are arranged in a staggered manner, the first photoresist unit provided with the anchor point is a non-measured first photoresist unit 201, and the non-measured first photoresist unit 201 and a measured first photoresist unit 204 are two different first photoresist units, as shown in Figure 3 As shown, the first photoresist units used for measuring the actual edge are two measured first photoresist units 204, 205 and a measured second photoresist unit 301 on both sides of the "+" sign, and the anchor point is arranged on another non-measured first photoresist unit 201 different from the two measured first photoresist units 204, 205. A distance between the anchor point and a target edge of the non-measured first photoresist unit 201 is usually set to be greater than a photoresist recession amount of the non-measured first photoresist unit 201, for example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400 nm to 500 nm, such as 450 nm, etc. In actual measurement, the "+" sign is preferably arranged in the center of optical measurement, and the anchor point is arranged in the range of optical measurement, for example, as shown by the dashed box in Figure 3 It is to be noted that the widths of the first photoresist units and the second photoresist units can be equal or unequal, and are not limited to the examples shown in the figure.
[0054] As shown in Figure 4 As shown, in one embodiment, the actual photoresist pattern includes a first photoresist column 20 and a second photoresist column 30, the first photoresist column 20 includes a plurality of first photoresist units arranged in a column direction with intervals, the second photoresist column 30 includes a plurality of second photoresist units arranged in a row direction opposite to the first photoresist units, the first photoresist units and the second photoresist units are arranged in a registered manner, a distance between two adjacent first photoresist units is greater than 2 times of a minimum feature size of a current process, the anchor point is a protruding structure 203 arranged on a side edge of the first photoresist unit, and a height and a width of the protruding structure 203 are preferably set as the minimum feature size of the current process to save space. The first photoresist unit provided with the anchor point is a non-measured first photoresist unit 201, and the non-measured first photoresist unit 201 and a measured first photoresist unit 204 are two different first photoresist units, as shown in Figure 4As shown in FIG. 2, the first photoresist units used for measuring the actual edge are the first photoresist units 204 on both sides of the "+" sign and the second photoresist units 301 opposite to the first photoresist units 204 in the row direction. The anchor point is arranged on another non-measured first photoresist unit 201 different from the measured first photoresist unit 204. The distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is usually set to be greater than the photoresist recession amount of the non-measured first photoresist unit 201. For example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400-500 nm, such as 450 nm. In actual measurement, the "+" sign is preferably arranged at the center of the optical measurement, and the anchor point is arranged within the range of the optical measurement, for example, as shown by the dashed box in FIG. 2. Figure 4 In this embodiment, the widths of the first photoresist units and the second photoresist units can be set to be equal.
[0055] As shown in FIG. 2, the first photoresist units used for measuring the actual edge are the first photoresist units 204 on both sides of the "+" sign and the second photoresist units 301 opposite to the first photoresist units 204 in the row direction. The anchor point is arranged on another non-measured first photoresist unit 201 different from the measured first photoresist unit 204. The distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is usually set to be greater than the photoresist recession amount of the non-measured first photoresist unit 201. For example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400-500 nm, such as 450 nm. In actual measurement, the "+" sign is preferably arranged at the center of the optical measurement, and the anchor point is arranged within the range of the optical measurement, for example, as shown by the dashed box in FIG. 2. Figure 5 As shown in FIG. 2, the first photoresist units used for measuring the actual edge are the first photoresist units 204 on both sides of the "+" sign and the second photoresist units 301 opposite to the first photoresist units 204 in the row direction. The anchor point is arranged on another non-measured first photoresist unit 201 different from the measured first photoresist unit 204. The distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is usually set to be greater than the photoresist recession amount of the non-measured first photoresist unit 201. For example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400-500 nm, such as 450 nm. In actual measurement, the "+" sign is preferably arranged at the center of the optical measurement, and the anchor point is arranged within the range of the optical measurement, for example, as shown by the dashed box in FIG. 2. Figure 5 As shown in FIG. 2, the first photoresist units used for measuring the actual edge are the first photoresist units 204 on both sides of the "+" sign and the second photoresist units 301 opposite to the first photoresist units 204 in the row direction. The anchor point is arranged on another non-measured first photoresist unit 201 different from the measured first photoresist unit 204. The distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is usually set to be greater than the photoresist recession amount of the non-measured first photoresist unit 201. For example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400-500 nm, such as 450 nm. In actual measurement, the "+" sign is preferably arranged at the center of the optical measurement, and the anchor point is arranged within the range of the optical measurement, for example, as shown by the dashed box in FIG. 2. Figure 5 As shown in FIG. 2, the first photoresist units used for measuring the actual edge are the first photoresist units 204 on both sides of the "+" sign and the second photoresist units 301 opposite to the first photoresist units 204 in the row direction. The anchor point is arranged on another non-measured first photoresist unit 201 different from the measured first photoresist unit 204. The distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is usually set to be greater than the photoresist recession amount of the non-measured first photoresist unit 201. For example, the distance between the anchor point and the target edge of the non-measured first photoresist unit 201 is preferably 400-500 nm, such as 450 nm. In actual measurement, the "+" sign is preferably arranged at the center of the optical measurement, and the anchor point is arranged within the range of the optical measurement, for example, as shown by the dashed box in FIG. 2.
[0056] It should be noted that the number of anchor points (such as the protruding structure 203 or the connecting bridge structure 202) can also be set to multiple. When performing optical measurement, one or more anchor points can be simultaneously located by optical measurement. In fact, when multiple anchor points are set, it is only necessary to ensure that at least one anchor point is located by optical measurement to determine the target edge of the target photoresist pattern. Therefore, setting multiple anchor points can make it easier for anchor points to be optically measured, reducing the difficulty of optical measurement selection and improving measurement efficiency.
[0057] In one embodiment, Figure 5 The photoresist pattern shown is used as an example to illustrate. Figure 6 It is displayed as Figure 5 The principle diagram of measuring the amount of light resistance reduction is shown in the figure. The method for measuring the amount of light resistance reduction includes the following steps:
[0058] In step 1), a photoresist layer is provided, a target photoresist pattern is defined on the photoresist layer, and anchor points are set on the target photoresist pattern.
[0059] Step 2) Expose and develop the photoresist layer according to the defined target photoresist pattern to form an actual photoresist pattern with anchor points. The actual photoresist pattern formed is as follows: Figure 5 As shown, the actual photoresist pattern includes a first photoresist column 20 and a second photoresist column 30. The first photoresist column 20 includes a plurality of first photoresist units spaced apart in the column direction. The second photoresist column 30 includes a plurality of second photoresist units arranged opposite to the first photoresist units in the row direction. The first photoresist units and the second photoresist units are aligned. The anchor point is a protruding structure 203 provided on the side of the first photoresist unit. The untested first photoresist unit 201 and the tested first photoresist unit 204 with the anchor point are different first photoresist units, and the widths of the first photoresist units and the second photoresist units are unequal.
[0060] Step 3) Determine the target edge of the target photoresist pattern based on the anchor point position of the actual photoresist pattern. Figure 6 As shown, since the position of the anchor point is determined and can be located by optical measurement (such as electron microscope, etc.), for the entire photoresist pattern, the target edges of all first photoresist units and second photoresist units can be accurately determined based on the position of the anchor point. In this embodiment, the first photoresist unit 204 to be measured and the first photoresist unit 201 not to be measured where the anchor point is set are two different first photoresist units, thereby avoiding the influence of the measurement effect due to a short measurement distance, thereby improving the measurement accuracy. Figure 6 As shown, the target edge 206 of the first light blocking unit 204 can be accurately determined by the position of the anchor point. At the same time, the target edge 302 of the second light blocking unit 301 can also be accurately determined by the position of the anchor point.
[0061] Step 4), the actual edge of the actual photoresist pattern is obtained by measurement. As shown in Figure 6 The first photoresist unit 204 to be measured and the second photoresist unit 301 to be measured have a certain amount of recession due to diffraction and interference effects, and the actual edge after recession can be determined by optical measurement (such as electron microscopy, etc.).
[0062] Step 5), the photoresist recession amount of the actual photoresist pattern is obtained based on the distance between the actual edge and the target edge.
[0063] As shown in Figure 6 The actual edge of the first photoresist unit 204 to be measured is obtained by optical measurement, and the photoresist recession amount D11 of the first photoresist unit is obtained based on the distance between the actual edge and the target edge 206. At the same time, the actual edge of the second photoresist unit 301 to be measured can be obtained by optical measurement, and the photoresist recession amount D12 of the second photoresist unit can be obtained based on the distance between the actual edge and the target edge 302.
[0064] It should be noted that when the first photoresist units in the first photoresist column 20 have consistent shape and size, the photoresist recession amount D11 obtained above can be extended to the entire first photoresist column; similarly, when the second photoresist units in the second photoresist column 30 have consistent shape and size, the photoresist recession amount D12 obtained above can be extended to the entire second photoresist column.
[0065] The embodiment also provides an optical proximity correction method, which comprises:
[0066] Step 1), determining a lithography process parameter according to a target photoresist pattern;
[0067] Step 2), establishing an optical proximity correction model according to the lithography process parameter;
[0068] Step 3), obtaining the photoresist recession amount of the actual photoresist pattern by the photoresist recession amount measurement method of the above embodiment;
[0069] Step 4), substituting the photoresist recession amount data of the actual photoresist pattern into the optical proximity correction model to obtain a simulation correction pattern.
[0070] As described above, the photoresist recession amount measurement method and the optical proximity correction method of the present application have the following beneficial effects:
[0071] The present application sets an anchor point in the lithography pattern as a positioning basis, and based on the anchor point, the accurate target edge of the photoresist pattern can be obtained. After the actual edge of the photoresist pattern is obtained by measurement, the photoresist recession amount of the photoresist pattern can be obtained through the distance between the actual edge and the target edge, i.e. the change amount of each photoresist line end pattern can be accurately obtained.
[0072] After the photoresist removal amount is obtained, a simulation correction pattern can be obtained from an optical proximity correction model by using the photoresist removal amount, so as to be used in actual mass production, and product yield can be greatly improved.
[0073] Therefore, the present application effectively overcomes the shortcomings in the prior art and has high industrial utilization value.
[0074] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.
Claims
1. A method for measuring the amount of photoresistance degradation, characterized in that: The measuring method comprises: Providing a photoresist layer, defining a target photoresist pattern on the photoresist layer, and setting an anchor point on the target photoresist pattern; exposing and developing the photoresist layer according to a defined target photoresist pattern to form an actual photoresist pattern having anchor points; determining a target edge of the target light-resistance pattern based on an anchor point position of the actual light-resistance pattern; obtaining an actual edge of the actual photoresist pattern by measuring; A photoresist retreat amount of the actual photoresist pattern is acquired based on a distance between the actual edge and the target edge.
2. The method for measuring the amount of photoresist degradation according to claim 1, wherein: The actual photoresist pattern includes a plurality of first photoresist units spaced apart in a column direction, wherein a target edge of the first photoresist unit to be measured is obtained based on the position of the anchor point, an actual edge of the first photoresist unit to be measured is obtained by measurement, and an amount of photoresist retreat of the first photoresist unit to be measured is obtained based on a distance between the actual edge and the target edge.
3. The method for measuring the amount of photoresist degradation according to claim 2, wherein: The anchoring point includes a protruding structure provided on one or more sides of the first light blocking units or a connecting bridge structure connecting two adjacent first light blocking units.
4. The method for measuring the amount of photoresist degradation according to claim 3, wherein: The distance between two adjacent first photoresist units is greater than 2 times the minimum feature size of the current process technology. The anchor point is a protruding structure set on the side of the first photoresist unit, and the height and width of the protruding structure are both set to the minimum feature size of the current process technology.
5. The method for measuring the amount of photoresist degradation according to claim 3, wherein: The spacing between two adjacent first photoresist units is less than or equal to 2 times the minimum feature size of the current process technology, the anchor point is set to a connecting bridge structure connecting the two adjacent first photoresist units, and the width of the connecting bridge structure is set to the minimum feature size of the current process technology.
6. The method for measuring the amount of photoresist degradation according to claim 3, wherein: The first photoresist unit provided with the anchor point is a first photoresist unit not to be tested, and the first photoresist unit not to be tested and the first photoresist unit to be tested are two different first photoresist units.
7. The method for measuring the amount of photoresist degradation according to claim 1, wherein: The distance between the anchor point and the target edge is greater than the photoresist retreat amount of the actual photoresist pattern.
8. The method for measuring the amount of photoresist degradation according to claim 7, wherein: The distance between the anchor point and the target edge is 400 nanometers to 500 nanometers.
9. The method for measuring the amount of photoresist degradation according to claim 2, wherein: The actual photoresist pattern further includes a plurality of second photoresist units arranged opposite to the first photoresist units in a row direction, and the measuring method further includes: Acquire a target edge of the second photoresist unit to be measured based on the position of the anchor point; Acquire the actual edge of the second photoresist unit to be measured by measuring; The photoresist fading amount of the second photoresist unit to be measured is obtained based on the distance between the actual edge and the target edge of the second photoresist unit to be measured.
10. The method for measuring the amount of photoresist degradation according to claim 9, wherein: The pattern width of the second photoresist unit to be tested is different from that of the first photoresist unit to be tested.
11. The method for measuring the amount of photoresist degradation according to claim 9, wherein: The plurality of first photoresist units and the plurality of second photoresist units are aligned or staggered.
12. An optical proximity correction method, characterized in that: The optical proximity correction method comprises: Determine the photolithography process parameters according to the target photoresist pattern; establishing an optical proximity correction model according to the photolithography process parameters; Obtaining the photoresist retreat amount of the actual photoresist pattern by the photoresist retreat amount measurement method according to any one of claims 1 to 11; The photoresist retreat amount data of the actual photoresist pattern is substituted into the optical proximity correction model to obtain a simulated correction pattern.
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