Method for identifying graphs according to layers

Abstract

The invention provides a method for identifying a pattern according to layers, which comprises the following steps of: providing a design file of a photoetching mask, and representing a polygon in a layered form by the design file; each layer of polygon is evenly divided into a plurality of strip-shaped areas, a first set value is assigned to the strip-shaped area located inside the polygon, a second set value is assigned to the strip-shaped area located outside the polygon, and the first set value and the second set value are different; endowing each layer of polygons with a specific coefficient; representing a numerical value sequence of each strip-shaped region: multiplying the assigned value of the strip-shaped region in each layer of polygon by a corresponding coefficient, and carrying out superposition; and recognizing the pattern according to the numerical sequence of all the strip-shaped areas. According to the method, the graphs needing to be recognized are stacked according to layers, and the stacked region values are retrieved, so that rapid recognition of the graphs is realized.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and particularly to a method for identifying patterns hierarchically. Background Art

[0002] During the design process of a mask, it is necessary to check whether the patterns are correctly placed. As Figure 1 shown, the ROTATION pattern is used to test the rotation error between masks. The ROTATION spliced between two shots forms a complete pattern. Therefore, if a pattern is missing, it will cause problems such as mask reset and wafer waste.

[0003] The detection of patterns in the prior art is based on logical judgment, that is, judging whether the pattern coordinate positions are correct, but it is also very easy to miss inspections.

[0004] Identifying patterns in the prior art requires geometric comparison of patterns to detect whether the patterns are correctly placed, which is very slow. Especially for patterns after OPC (Optical Proximity Correction), the data volume is very large, resulting in a waste of a large amount of computing resources.

[0005] As Figure 2 shown, at three positions A, B, and C in different positions of the dicing slot, only A is correct.

[0006] To solve the above problems, a new method for identifying patterns hierarchically needs to be proposed. Summary of the Invention

[0007] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method for identifying patterns hierarchically, which is used to solve the problem that in the prior art, identifying patterns requires geometric comparison of patterns to detect whether the patterns are correctly placed, which is very slow. Especially for patterns after OPC (Optical Proximity Correction), the data volume is very large, resulting in a waste of a large amount of computing resources.

[0008] To achieve the above object and other related objects, the present invention provides a method for identifying patterns hierarchically, including:

[0009] Step 1: Provide a design file of a photolithography mask, and the design file represents polygons in a hierarchical form;

[0010] Step 2: Uniformly divide each layer of the polygons into a plurality of strip-shaped regions, assign a first set value to the strip-shaped regions located inside the polygons, and assign a second set value to the strip-shaped regions located outside the polygons, where the first and second set values are different;

[0011] Step 3: Assign a specific coefficient to each layer of the polygons;

[0012] Step 4: Characterize the numerical sequence of each of the strip regions: Multiply the value assigned to the strip region in each layer of the polygon by the corresponding coefficient and perform superposition.

[0013] Step 5: Identify the pattern based on the numerical sequences of all the strip regions.

[0014] Preferably, the design file of the mask in Step 1 is in the GDSII format.

[0015] Preferably, the topography of the strip regions in each layer of the polygon in Step 2 is the same.

[0016] Preferably, the first set value in Step 2 is 1.

[0017] Preferably, the second set value in Step 2 is 0.

[0018] As described above, the method for identifying patterns hierarchically according to the present invention has the following beneficial effects:

[0019] The present invention superimposes the patterns to be identified hierarchically and retrieves the region values after superposition, achieving fast identification of patterns. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of a rotated pattern shown as prior art;

[0021] Figure 2 Schematic diagram of geometric comparison of a pattern shown as prior art;

[0022] Figure 3 Schematic diagram of the method for identifying patterns hierarchically according to the present invention;

[0023] Figure 4 Schematic diagram of value assignment to strip regions according to the present invention;

[0024] Figure 5 Schematic diagram of assigning specific coefficients to each layer of polygon according to the present invention;

[0025] Figure 6 Schematic diagram of characterizing the numerical sequence of strip regions according to the present invention;

[0026] Figure 7 Schematic diagram of comparison of numerical sequences of two patterns according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0028] Please refer to Figure 3 , the present invention provides a method for identifying a graphic by hierarchy, including:

[0029] Step 1: Provide a design file of a photolithography mask plate, and the design file represents polygons in a hierarchical form;

[0030] In some embodiments, the design file of the mask plate in Step 1 is in the GDSII format. The GDSII stream format, commonly abbreviated as GDSII, is a database file format. It is used for data conversion of integrated circuit layouts and has become the de facto industry standard. GDSII is a binary file that contains planar geometries, texts or labels in an integrated circuit layout, as well as other relevant information and can be composed of a hierarchical structure. GDSII data can be used to reconstruct all or part of the layout information. It can be used to fabricate a photolithography mask plate.

[0031] Step 2: Uniformly divide each layer of polygons into multiple strip regions, assign a first set value to the strip regions located inside the polygon, and assign a second set value to the strip regions located outside the polygon, where the first and second set values are different;

[0032] In some embodiments, the morphologies of the strip regions in each layer of polygons in Step 2 are the same.

[0033] In some embodiments, the first set value in Step 2 is 1.

[0034] In some embodiments, the second set value in Step 2 is 0. In other embodiments, the first and second set values can also be adjusted, and no specific limitation is made here.

[0035] Step 3: Assign a specific coefficient to each layer of polygons;

[0036] Step 4: Characterize the numerical sequence of each strip region: multiply the assignment of the strip region in each layer of polygons by the corresponding coefficient and perform superposition;

[0037] Step 5: Identify the graphic according to the numerical sequences of all strip regions.

[0038] For example, please refer to Figure 4, for the two polygons of layer a and layer b, the strip regions located inside the polygon of layer a are assigned 1, those inside the polygon of layer b are assigned 1, and those outside the polygon are assigned 0.

[0039] Please refer to Figure 5 , for both layer a and layer b, a specific coefficient of 0.5 is assigned.

[0040] Please refer to Figure 6 , the value of the strip region located at layer a and layer b is 1*0.5 + 1*0.5 = 1, the value of the strip region located at layer a is 1*0.5 = 0.5, and the values of the strip regions outside the polygon are all 0.

[0041] Please refer to Figure 7 , it can be clearly found that the numerical sequences of the two figures are inconsistent.

[0042] It should be noted that the illustrations provided in this embodiment only schematically illustrate the basic concept of the present invention. Therefore, only the components related to the present invention are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0043] In summary, the present invention superimposes the figures to be recognized by layers and retrieves the region values after superposition, achieving rapid recognition of the figures. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0044] The above embodiments are only illustrative of the principles and effects of the present invention, and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for identifying graphics by level, characterized in that: At least: Step 1: providing a design file of a photolithography mask, wherein the design file represents polygons in a layered form; Step 2: Evenly divide the polygon of each layer into a plurality of strip regions, assign a first set value to the strip region inside the polygon, and assign a second set value to the strip region outside the polygon, wherein the first and second set values ​​are different; Step 3, assigning specific coefficients to the polygons of each layer; Step 4: a numerical sequence representing each of the strip regions: multiplying the value of the strip region in each layer of the polygon by the corresponding coefficient to perform superposition; Step 5: Identify a pattern based on the numerical sequence of all the strip-shaped areas.

2. The method for identifying graphics by level according to claim 1, characterized in that: The design file of the mask in step 1 is in GDSII format.

3. The method for identifying graphics by level according to claim 1, characterized in that: In step 2, the morphology of the strip-shaped regions in each layer of the polygon is consistent.

4. The method for identifying graphics by level according to claim 1, characterized in that: The first set value in step 2 is 1.

5. The method for identifying graphics by level according to claim 4, characterized in that: The second set value in step 2 is 0.

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