Optical property modeling method and device

Abstract

The present invention discloses an optical property modeling method and device, which comprises: dividing a microstructure in a periodic medium into N layers of thin slices in the z direction; performing the following processing for thin slices of the same layer of microstructure: obtaining geometric information of each closed area projected by the thin slice on the xy plane of the periodic space; dividing the periodic space according to the geometric information to obtain a target integral sub-interval divided in the x direction and a target integral sub-interval divided in the y direction; calculating the Fourier coefficient of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium, and performing strict coupled wave analysis to realize optical property modeling of the periodic medium. The method optimizes the division method of the integral interval, thereby efficiently obtaining the accurate Fourier coefficient of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to an optical property modeling method and device. Background Art

[0002] In the fields of semiconductor manufacturing inspection, optical proximity correction of photolithography masks, optical scattering simulation calculation, etc., it is necessary to expand the two-dimensional Fourier coefficients of the dielectric coefficients of periodic media. Taking the field of semiconductor inspection as an example, with the development of the semiconductor manufacturing industry, the device structure is becoming more and more complex as the feature size decreases. In order to ensure the reliability and consistency of manufacturing, stricter process control is required for the manufacturing process. Measuring the manufactured devices is one of the core issues in process control. Optical critical dimension (OCD) measurement technology has the advantages of fast speed, low cost, and non-destructiveness. It has important applications in advanced process control of semiconductor manufacturing. Optical critical dimension measurement technology is a model-based method, so fast and accurate modeling calculation is one of the core elements of optical critical dimension measurement.

[0003] Optical critical dimension measurement is supported by two key technologies, namely forward optical property modeling and reverse geometric parameter extraction. Among many forward optical property modeling methods, rigorous coupled wave analysis theory (RCWA) is widely used in the optical property modeling of periodic media due to its high modeling accuracy and wide applicability. In the process of rigorous coupled wave analysis, it is necessary to obtain the Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium.

[0004] In recent years, in order to ensure that semiconductor devices maintain excellent performance while the critical dimension (CD) continues to shrink, their structural design has gradually shifted from simple planar structures to complex three-dimensional structures. Three-dimensional structures mainly include multi-coatings, multi-patterns, and curved edge structures. The more complex the structure, the more prominent the contradiction between the computational efficiency and computational accuracy of optical property modeling, and the time consumed by existing technologies to obtain high-precision theoretical spectra has increased dramatically.

[0005] The Fourier coefficient solution method of the dielectric constant of the periodic medium provided in the prior art often divides the periodic space into grids uniformly, and then uses the dielectric constant of the center of each grid as the dielectric constant of the grid, and then performs a two-dimensional fast Fourier transform to obtain the Fourier coefficient of the dielectric constant. The Toeplitz matrix of the dielectric constant of the periodic medium is generally to uniformly divide the intervals in the corresponding directions along the X direction and the Y direction in the periodic space, and then uses the dielectric constant of the midpoint of each interval as the dielectric constant of the interval, and then integrates in the Y direction and the X direction respectively, and then performs a one-dimensional fast Fourier transform to obtain. The prior art has the following problems: if the periodic space is divided into more integral intervals, although the calculation accuracy can be improved, there is a problem of time-consuming calculation, which affects the efficiency of forward optical property modeling; and if the periodic space is divided into fewer integral intervals, although the calculation efficiency can be improved, there is a problem of low calculation accuracy, which affects the accuracy of forward optical property modeling. Summary of the invention

[0006] An embodiment of the present invention provides an optical property modeling method and device, which optimizes the method of dividing the integral interval based on the geometric information of the microstructure, so as to efficiently obtain the accurate Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium, and finally complete the optical property modeling efficiently and accurately.

[0007] In a first aspect, the present invention provides a method for modeling optical properties, wherein the method comprises the following steps: dividing a microstructure in a periodic medium into N thin slices in the z direction, where N is a positive integer;

[0008] For the slices of the same microstructure, the following processing is performed:

[0009] Obtaining geometric information of each closed area of ​​the sheet projected on the periodic space xy plane;

[0010] The periodic space is divided according to the geometric information to obtain target integral sub-intervals divided in the x-direction and target integral sub-intervals divided in the y-direction.

[0011] The Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium are calculated; and a rigorous coupled wave analysis is performed using the Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium to achieve optical property modeling of the periodic medium.

[0012] The beneficial effect of the optical property modeling method provided by the present invention is that by dividing the microstructure in the periodic medium into thin slices and projecting them onto the xy plane, the method of dividing the integral interval can be optimized based on the geometric information of the closed area formed by the projection of the thin slice of the microstructure, so as to efficiently obtain the accurate Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient, thereby further improving the efficiency and accuracy of forward optical property modeling.

[0013] In a possible embodiment, the step of obtaining geometric information of each closed area projected by the thin film on the xy plane of the periodic space includes: obtaining each closed area projected by the thin film on the xy plane of the periodic space, and representing the boundaries of each closed area as each polygon; obtaining the x-coordinate and y-coordinate of each polygon vertex to form a set of x-coordinates and a set of y-coordinates.

[0014] In another possible embodiment, dividing the periodic space into grids and intervals according to the geometric information to obtain a target integral subinterval divided in the x direction and a target integral subinterval divided in the y direction includes: arranging the coordinates in the set of x coordinates and the set of y coordinates in order from large to small or from small to large, respectively, and any two adjacent coordinates in the set of x coordinates and the set of y coordinates after the arrangement constitute a candidate integral subinterval;

[0015] Determine whether the candidate integral sub-interval is a non-uniform interval; obtain the length of the candidate integral sub-interval; when the candidate integral sub-interval is a non-uniform interval and the length of the candidate integral sub-interval is greater than or equal to a preset step size, divide the candidate integral sub-interval into multiple target integral sub-intervals; otherwise, take the candidate integral sub-interval as a target integral sub-interval.

[0016] In a possible embodiment, determining whether the candidate integral subinterval is a non-uniform interval includes: acquiring a first reference boundary line and a second reference boundary line of the candidate integral subinterval formed by the two adjacent coordinates in the x-direction, the first reference boundary line and the second reference boundary line being non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the first reference boundary line and the second reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval;

[0017] Obtaining the number h of first boundary intersection points formed by the intersection of the first reference boundary line and the polygon, and the number k of second boundary intersection points formed by the intersection of the second reference boundary line and the polygon;

[0018] When h is not equal to k, the candidate integral subinterval is taken as a non-uniform interval; or, when h is equal to k and not equal to zero, the y coordinates (α1, α2, ..., αh) of the first boundary intersection point and the y coordinates (β1, β2, ..., βk) of the second boundary intersection point are obtained, wherein the y coordinates of the h boundary intersection points and the y coordinates of the k boundary intersection points are arranged in order from large to small or from small to large; and Δ1=|α1-β1|+|α2-β2|+...+|αh-βk| is greater than or equal to a threshold, the candidate integral subinterval is taken as a non-uniform interval; when h is equal to k and equal to zero, the candidate integral subinterval is taken as a uniform interval;

[0019] Alternatively, when h is equal to k and not equal to zero, and Δ1=|α1-β1|+|α2-β2|+ ... +|αh-βk| is smaller than the threshold, the candidate integral subinterval is taken as a uniform interval.

[0020] In the method, for any candidate integral subinterval in the x direction, when the length of the candidate integral subinterval is less than the preset step length, the candidate integral subinterval is directly used as a target integral subinterval without further division, which can reduce the complexity of subsequent calculations without affecting the accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium. For candidate integral subintervals greater than or equal to the preset step length, further division can be performed based on whether the integral subinterval is uniform, so as to reduce the complexity of subsequent calculations and improve the accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium.

[0021] In a possible embodiment, determining whether the candidate integral subinterval is a non-uniform interval includes: obtaining a third reference boundary line and a fourth reference boundary line of the candidate integral subinterval formed by the two adjacent coordinates in the y direction, the third reference boundary line and the fourth reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the third reference boundary line and the fourth reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval;

[0022] Obtaining the number u of third boundary intersection points formed by the intersection of the third reference boundary line and the polygon, and the number v of fourth boundary intersection points formed by the intersection of the fourth reference boundary line and the polygon;

[0023] When u is not equal to v, the candidate integral subinterval is taken as a non-uniform interval; or, when u is equal to v and not equal to zero, the x-coordinate (σ1, σ2, ..., σu) of the third boundary intersection point and the x-coordinate (ω1, ω2, ..., ωv) of the fourth boundary intersection point are obtained, wherein the x-coordinates of the u boundary intersection points and the x-coordinates of the v boundary intersection points are arranged in order from large to small or from small to large; and Δ2 = |σ1-ω1|+|σ2-ω2|+...+|σu-ωv| is greater than or equal to a set threshold, the candidate integral subinterval is taken as a non-uniform interval; when u is equal to v and equal to zero, the candidate integral subinterval is taken as a uniform interval;

[0024] Alternatively, when u is equal to v and not equal to zero, and Δ2=|σ1-ω1|+|σ2-ω2|+...+|σu-ωv| is smaller than the set threshold, the candidate integral sub-interval is taken as a uniform interval.

[0025] In the method, for any candidate integral sub-interval in the y direction, when the length of the candidate integral sub-interval formed by two adjacent coordinates is less than the preset step length, the candidate integral sub-interval is directly used as a target integral sub-interval without further division, which can reduce the complexity of subsequent calculations without affecting the accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium. For candidate integral sub-intervals greater than or equal to the preset step length, further division can be performed based on whether the integral sub-interval is uniform, so as to reduce the complexity of subsequent calculations and improve the accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium.

[0026] In a second aspect, an embodiment of the present application further provides an optical property modeling device, which includes a module / unit for executing any possible design method of the first aspect. These modules / units can be implemented by hardware, or by executing corresponding software implementations by hardware.

[0027] For the beneficial effects of the second aspect, please refer to the description of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of a method for dividing a grid in a periodic space and integral sub-intervals in the x-direction provided by the prior art;

[0030] Figure 2 A schematic diagram of a process flow of an optical property modeling method provided in an embodiment of the present application;

[0031] Figure 3 A schematic diagram of a microstructure z-direction divided slice provided in an embodiment of the present application;

[0032] Figure 4 A top view of a plurality of polygons in a periodic space obtained by projecting any thin sheet in the z direction on the xy plane provided in an embodiment of the present application;

[0033] Figure 5 A schematic diagram of a method for dividing candidate integral sub-intervals provided in an embodiment of the present application;

[0034] Figure 6 A schematic diagram of a method for determining whether a candidate integral sub-interval in the x-direction is uniform provided in an embodiment of the present application;

[0035] Figure 7 A schematic diagram of a reference boundary of a candidate integral sub-interval in the x-direction provided in an embodiment of the present application;

[0036] Figure 8 A schematic diagram of dividing a target integral sub-interval provided in an embodiment of the present application;

[0037] Fig. 9 A schematic diagram of a method for determining whether a candidate integral sub-interval in the y direction is uniform provided in an embodiment of the present application;

[0038] Fig.10 (a) is a side view of a microstructure provided in an embodiment of the present application, which is a prism;

[0039] Fig.10 (b) in Fig.10 One of the microstructures in (a) is a top view of a thin slice after prism delamination;

[0040] Fig.11 (a) is a side view of an elliptical cone microstructure provided in an embodiment of the present application;

[0041] Fig.11 (b) in Fig.11 One of the microstructures in (a) is a top view of a thin slice after elliptical cone layering;

[0042] Fig.12 A top view of a thin slice after layering of a microstructure of a rotating elliptical cone;

[0043] Fig.13 A schematic diagram of an optical property modeling device provided in an embodiment of the present application;

[0044] Fig.14 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned purposes, features and advantages of the embodiments of the present invention more obvious and easy to understand, the prior art solutions and the technical solutions in the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0046] In the prior art, considering the periodic changes of periodic media, the periodic space is generally divided into grids uniformly, such as Figure 1 As shown, the dielectric coefficient of each grid center is taken as the dielectric coefficient of the grid, and a two-dimensional fast Fourier transform is performed to obtain the Fourier coefficient ε of the dielectric coefficient ε(x,y) of the periodic medium. mn In addition, the intervals are evenly divided along the x and y directions in the periodic space, and the dielectric constant of the midpoint of each integral interval is used as the dielectric constant of the interval. Then, the dielectric constants of the interval are integrated in the y and x directions respectively, and then a one-dimensional fast Fourier transform is performed to obtain the Toeplitz matrix of the dielectric constant ε(x,y) of the periodic medium. . This method has the following problems: if the periodic space is divided into many intervals, although the calculation accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium can be improved, there is a problem of time-consuming calculation; and if the periodic space is divided into few intervals, although the calculation efficiency can be improved, there is a problem of low calculation accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium, which affects the efficiency of forward optical property modeling. Therefore, it is necessary to study an efficient and accurate calculation method of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium, so as to solve the problem that the efficiency and accuracy of forward optical property modeling cannot be achieved at the same time.

[0047] To this end, the optical property modeling method provided by the present invention optimizes the division of the integral interval based on the geometric information of the microstructure of the periodic medium in the periodic space, and obtains the optimized grid based on the optimized divided interval, rather than uniformly dividing the integral interval and the grid in the entire area in the periodic space, thereby further improving the Fourier coefficient ε of the dielectric coefficient of the periodic medium. mn and the Toeplitz matrix of the dielectric constant of a periodic medium and The computational efficiency and accuracy of the model are improved.

[0048] like Figure 2As shown, the present invention provides an optical property modeling method, the method comprising the following steps:

[0049] S201, dividing the microstructure in the periodic medium into N thin slices in the z direction, where N is a positive integer.

[0050] In the periodic space, the periodic medium may include several independent microstructures, and each microstructure needs to be divided into multiple slices in the z direction. For example, assuming that the side view of a microstructure is as follows Figure 3 As shown in the left figure in the figure, the microstructure is usually not constant in the z direction. The microstructure is divided into several thin layers in the z direction, and the thickness of the thin layers is small enough, such as Figure 3 As shown in the right figure in , the light scattering characteristics of each layer of thin film are uniform and unchanged in the z direction, so the light scattering effect of the entire microstructure can be regarded as the light scattering effect of several thin films with uniform distribution in the z direction superimposed on each other.

[0051] S202, for a thin slice of the same layer of microstructure, perform the following processing: obtain geometric information of each closed area of ​​the thin slice projected on the xy plane of the periodic space; divide the periodic space according to the geometric information to obtain the target integral sub-interval divided in the x direction and the target integral sub-interval divided in the y direction.

[0052] In addition, optionally, when projecting, the periodic space is also treated as a polygon and the periodic space is taken as -p in the x direction. x / 2~p x / 2, the value in the y direction is -p y / 2~p y / 2, p x and p y are the period lengths of the periodic space in the x and y directions respectively.

[0053] S203, calculating the Fourier coefficient ε of the dielectric constant of the periodic medium mn and the Toeplitz matrix of the dielectric constant of a periodic medium and

[0054] S204, performing rigorous coupled wave analysis using the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium to achieve optical property modeling of the periodic medium.

[0055] Specifically, based on the Fourier coefficient ε of the dielectric constant of the periodic medium mn , the Toeplitz matrix of the dielectric constant of a periodic medium and The theoretical spectrum is calculated using the rigorous coupled wave analysis (RCWA) theoretical algorithm.

[0056] In the above method, the Fourier coefficients of the dielectric function of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium need to be divided into grids and intervals respectively. Compared with the prior art, the prior art divides the grids and intervals uniformly, does not consider the geometric information of the microstructure in the periodic medium, but directly divides the entire periodic space uniformly, and the uniform division of the periodic space corresponding to the geometric information of the microstructure does not change or changes slightly increases the amount of calculation. For the uniform division of the periodic space corresponding to the large change in the geometric information of the microstructure, if the number of divisions is sufficient, the amount of calculation increases sharply, and if the number of divisions is small, the calculation error increases, and the accuracy of obtaining the theoretical spectrum is reduced. The embodiment of the present invention optimizes the division of grids and intervals based on the geometric information of each closed area projected by the thin sheet on the xy plane of the periodic space, reduces the number of grid and interval divisions, reduces the amount of calculation, and improves the calculation accuracy, thereby overcoming the defects of the prior art, and the geometric information of the closed area is directly determined by the geometric information of the microstructure. Therefore, based on the target integral quantile interval obtained by this method, the Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium with high precision can be obtained more efficiently, thereby improving the efficiency and accuracy of calculating the theoretical spectrum.

[0057] In one possible implementation, a specific method for obtaining geometric information of each closed area projected by the thin film on the xy plane of the periodic space may be: obtaining each closed area projected by the thin film on the xy plane of the periodic space, and representing the boundaries of each closed area as each polygon; obtaining the x-coordinate and y-coordinate of each polygon vertex to form a set of x-coordinates and a set of y-coordinates.

[0058] In another possible implementation, the periodic space may be divided according to the geometric information as follows: arranging the coordinates in the x-coordinate set and the y-coordinate set in order from large to small or from small to large, respectively, wherein any two adjacent coordinates in the x-coordinate set and the y-coordinate set after the sequential arrangement constitute a candidate integral sub-interval; determining whether the candidate integral sub-interval is a non-uniform interval, and obtaining the length of the candidate integral sub-interval; when the candidate integral sub-interval is a non-uniform interval and the length of the candidate integral sub-interval is greater than or equal to a preset step size, dividing the candidate integral sub-interval into multiple target integral sub-intervals; otherwise, treating the candidate integral sub-interval as a target integral sub-interval.

[0059] In the above steps, in detail, the shapes of the microstructures are diverse, and the corresponding geometric structures are also diverse. Non-polygonal geometric structures can be approximated as polygons, and polygons have multiple vertices. For complex periodic media, there are multiple microstructures in one periodic unit. Figure 4 The top view of a periodic unit obtained by projecting any thin slice in the z direction on the xy plane has multiple polygons. It can be seen from the figure that there are multiple polygons such as triangles, quadrilaterals and hexagons. In this example, the vertex coordinates of the triangle, the vertex coordinates of the quadrilateral points and the vertex coordinates of the hexagonal points can be obtained in sequence. Then, based on the vertex coordinates of the triangle, the vertex coordinates of the quadrilateral points and the vertex coordinates of the hexagonal points, the set of x coordinates of all vertices and the set of y coordinates of all vertices are constructed. Optionally, the x coordinate set can also include the x coordinate of the endpoint in the x direction of the periodic space-p x / 2 and p x / 2; the y coordinate set can also include the y coordinate of the endpoint in the y direction of the periodic space -p y / 2 and p y / 2. Optionally, in the process of constructing the set of x coordinates and the set of y coordinates, duplicate removal and sorting from large to small or from small to large can be performed. Taking the sorting from small to large as an example, the set of x coordinates of all polygon vertices is recorded as {-p x / 2,g0,g1,…,g τ ,p x / 2}, and -p x / 2 <g0<g1<…<g τ <p x / 2, τ is a natural number, and the set of y coordinates of all polygon vertices is denoted as {-p y / 2,η0,η1,…,η ζ ,p y / 2}, and -p y / 2<η0<η1<…<η ζ <p y / 2, ζ is a natural number. Afterwards, based on the coordinates in the set of coordinates in the x direction, the set of coordinates in the x direction is divided into multiple target integral subintervals to obtain multiple target integral subintervals in the x direction; and based on the coordinates in the set of coordinates in the y direction, the set of coordinates in the y direction is divided into multiple target integral subintervals to obtain multiple target integral subintervals in the y direction. In this method, for any candidate integral subinterval in the x direction and the y direction, when the length of the candidate integral subinterval formed by two adjacent coordinates is less than the preset step length, the candidate integral subinterval is directly used as a target integral subinterval without further division, which can reduce the complexity of subsequent calculations without affecting the accuracy of the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium. For candidate integral subintervals greater than or equal to the preset step length, it can be determined whether to further divide according to whether the integral subinterval is uniform, so as to improve the accuracy and calculation efficiency of calculating the Fourier coefficients of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium.

[0060] Among them, if the distribution of the periodic medium in the candidate integral sub-interval is uniform or there is no polygon in the candidate integral sub-interval, then the candidate integral sub-interval is uniform; if the distribution of the periodic medium in the candidate integral sub-interval is non-uniform, then the candidate integral sub-interval is non-uniform. Specifically, the following method can be used to determine whether the candidate integral sub-interval is uniform. For the candidate integral sub-interval in the x-direction, the number of first boundary intersections formed by the intersection of all polygonal boundaries in the candidate integral sub-interval with the first reference boundary line of the candidate integral sub-interval is the same as the number of second boundary intersections formed by the intersection of the polygonal boundaries with the second reference boundary line of the candidate integral sub-interval, and the sum of the absolute values ​​of the differences between the corresponding y values ​​of the first boundary intersection and the second boundary intersection is less than the threshold, then the candidate integral sub-interval is uniform, otherwise it is non-uniform; wherein the first reference boundary line and the second reference boundary line are non-overlapping straight lines perpendicular to the candidate integral sub-interval, and the intersection of the first reference boundary line and the second reference boundary line with the candidate integral sub-interval is not the endpoint of the candidate integral sub-interval; for For a candidate integral subinterval in the y direction, if the number of third boundary intersection points formed by the intersection of all polygonal boundaries with the third reference boundary line of the candidate integral subinterval in the candidate integral subinterval is the same as the number of fourth boundary intersection points formed by the intersection of the polygonal boundaries with the fourth reference boundary line of the candidate integral subinterval, and the sum of the absolute values ​​of the differences between the corresponding x values ​​of the third boundary intersection points and the fourth boundary intersection points is less than a threshold, then the candidate integral subinterval is a uniform interval, otherwise it is a non-uniform interval; wherein the third reference boundary line and the fourth reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and the intersection points of the third reference boundary line and the fourth reference boundary line with the candidate integral subinterval are not the endpoints of the candidate integral subinterval.

[0061] Taking the candidate integral subintervals in the x direction as an example, Figure 5 A schematic diagram showing a periodic unit containing multiple microstructures, obtaining the x-coordinate values ​​of all vertices of the polygon corresponding to each microstructure, and obtaining the candidate integral sub-intervals in the x-direction. Figure 5 The polygon in the middle is obtained by polygon processing the figure whose projection boundary of the microstructure thin layer is a curve. Arrange the x coordinate values ​​of all the above vertices in order from large to small or from small to large; any two adjacent coordinates in the sequentially arranged coordinate set constitute a candidate integral sub-interval, such as Figure 5 As shown, the candidate integral subinterval is (-p x / 2,g0),(g0,g1),(g1,g2)……(g 12 ,g 13 ), (g 13 ,g 14 ),(g 14,p x / 2).

[0062] This embodiment provides a method flow for determining whether a candidate integral subinterval is uniform, including the following steps: Figure 6 shown.

[0063] S601, obtaining a first reference boundary line and a second reference boundary line of any candidate integral subinterval in the x direction. For example, the two x coordinates of the candidate subinterval are g γ' and g γ'+1 , g γ' <g γ'+1 , with x = g γ' +δ1 represents the first straight line and x=g γ'+1 The second straight line represented by -δ2 serves as the first reference boundary line and the second reference boundary line of the candidate subinterval respectively.

[0064] Among them, γ' is a natural number, 0<δ1 <g γ'+1 -g γ' , 0<δ2 <g γ'+1 -g γ' , and g γ' +δ1≠g γ'+1 -δ2.

[0065] S602: Obtain the number h of first boundary intersection points formed by the intersection of the first reference boundary line and the polygon, and the number k of second boundary intersection points formed by the intersection of the second reference boundary line and the polygon.

[0066] S603, determine whether h is equal to k, if so, execute S604, if not, execute S608.

[0067] S604, determine whether h and k are equal to zero, if not, execute S605, if yes, execute S607.

[0068] S605, obtain the y coordinates of the first boundary intersection points (α1, α2, ..., αh), and the y coordinates of the second boundary intersection points (β1, β2, ..., βk), wherein the y coordinates of the h boundary intersection points and the y coordinates of the k boundary intersection points are arranged in order from large to small or from small to large; and Δ1 = |α1-β1|+|α2-β2|+...+|αh-βk|.

[0069] Optionally, if the periodic space is also regarded as a polygon during slice projection, in this step it is determined whether h and k are equal to 2, that is, when h and k are equal to 2, the candidate integral sub-interval is a uniform interval, if not equal to 2, then S605 is executed.

[0070] For example, the slice is projected into periodic space as a polygon, such as Figure 7 As shown, the first reference boundary line x=g γ' +δ1 intersects with the polygon to form four boundary intersection points with y coordinates of α1, α2, α3 and α4. The second reference boundary line x=g γ'+1 -δ2 intersects with the polygon to form four boundary intersection points with y coordinates of β1, β2, β3 and β4. Optionally, when the projection time does not treat the periodic space as a polygon, Figure 7 The first reference boundary line x=g γ' +δ1 and second reference boundary line = g γ'+1 -δ2 intersects with the polygon to form two boundary intersection points.

[0071] S606, determine whether Δ1 is less than a threshold, if so, execute S607, if not, execute S608.

[0072] For example, the threshold value may be the period length p in the x direction. x One percent or p x One thousandth of.

[0073] S607: Use the candidate integral sub-interval as a uniform interval.

[0074] S608: Use the candidate integral sub-interval as a non-uniform interval.

[0075] Furthermore, when the candidate integral subinterval in the x direction is a non-uniform interval, it can be divided according to a preset step size (according to experience 0.1-5nm), or it can be divided by binary division, or it can be divided by other division methods, and so on, completing the division of each candidate integral subinterval one by one to obtain the target integral subinterval in the x direction. For example, Figure 8 Shows the Figure 5 Schematic diagram of the target integral sub-interval obtained by dividing the candidate integral sub-interval in the x direction as shown in FIG. Figure 8 As shown, compared with the prior art that uniformly divides the periodic space, the method of the embodiment of the present invention uses a target integral sub-interval that is directly determined by the geometric information of the closed area of ​​the projection of the thin slice of the microstructure in the periodic medium, and the number of the target integral sub-intervals obtained is reduced, which reduces the amount of calculation, and the target integral sub-interval obtained can reflect the change of the geometric information of the microstructure in the periodic medium, further improving the accuracy of obtaining the theoretical spectrum, and overcoming the defect of the prior art that the calculation efficiency and the calculation accuracy cannot be achieved at the same time; in addition, the more complex the microstructure in the periodic medium, the more obvious the effect of the embodiment of the present invention on improving the calculation efficiency and the calculation accuracy.

[0076] like Fig. 9As shown, with respect to whether the candidate integral subintervals in the y direction are uniform, this embodiment provides a judgment method flow, including the following steps.

[0077] S901, obtaining a third reference boundary line and a fourth reference boundary line of any candidate integral subinterval in the y direction. Exemplarily, the two y coordinates of the candidate integral subinterval are n e' and η e'+1 , η e' <η e'+1 , with y = η e' +δ1' represents the third straight line and y=η e'+1 The fourth straight line represented by -δ2' is used as the third reference boundary line and the fourth reference boundary line of the candidate integral sub-interval respectively.

[0078] Among them, e' is a natural number, 0<δ1'<η e'+1 -η e' , 0<δ2'<η e'+1 -η e' , and η e' +δ1'≠η e'+1 -δ2'.

[0079] S902: Obtain the number u of third boundary intersection points formed by the intersection of the third reference boundary line and the polygon, and the number v of fourth boundary intersection points formed by the intersection of the fourth reference boundary line and the polygon.

[0080] S903, determine whether u is equal to v, if so, execute S904, if not, execute S908.

[0081] S904, determine whether u and v are equal to zero, if not, execute S905, if yes, execute S907.

[0082] S905, obtain the x-coordinate (σ1, σ2, ..., σu) of the third boundary intersection point, and the x-coordinate (ω1, ω2, ..., ωv) of the fourth boundary intersection point, wherein the x-coordinates of u boundary intersection points and the x-coordinates of v boundary intersection points are arranged in order from large to small or from small to large; and Δ2 = |σ1-ω1|+|σ2-ω2|+...+|σu-ωv|.

[0083] Optionally, if the periodic space is also regarded as a polygon during slice projection, in this step it is determined whether u and v are equal to 2, that is, when u and v are equal to 2, the candidate integral sub-interval is a uniform interval, if not equal to 2, then S905 is executed.

[0084] S906, determine whether Δ2 is less than a set threshold, if so, execute S907, if not, execute S908.

[0085] For example, the threshold value may be set to be the period length p in the y direction. y One percent of the period length p in the y direction y One thousandth of.

[0086] S907: Use the candidate integral sub-interval as a uniform interval.

[0087] S908: Use the candidate integral sub-interval as a non-uniform interval.

[0088] Based on the above steps, when the candidate integral sub-interval in the y direction is a non-uniform interval, it can be divided according to a preset step size (according to experience 0.1-5nm), or it can be divided by binary division, or other division methods can be used to continue to divide the candidate integral sub-interval, and so on, completing the division of each candidate integral sub-interval one by one to obtain the target integral sub-interval in the y direction.

[0089] In a possible embodiment, based on the above target integral subintervals in the x direction and the target integral subintervals in the y direction, a grid composed of the target integral subintervals in the x direction and the target integral subintervals in the y direction can be obtained, assuming that they are respectively recorded as c1, c2, …, c φ , a total of φ grids, the target integral sub-interval obtained in the x direction is recorded as (-p x / 2,t0),(t0,t1),(t1,t2),…,(t γ-1 ,t γ ),(t γ ,p x / 2), the target integral sub-interval obtained in the y direction is recorded as (-p y / 2,s0),(s0,s1),(s1,s2),…,(s e-1 ,s e ),(s e ,p y / 2). Then the Toeplitz matrix of the dielectric constant ε(x,y) of the periodic medium is jl The Toeplitz matrix of the dielectric constant ε(x,y) of the periodic medium satisfies the following formula 1: jl The following formula 2 is satisfied.

[0090]

[0091]

[0092] The Fourier coefficient of the dielectric constant ε(x,y) of the periodic medium satisfies the following formula 3:

[0093]

[0094] Where i is the imaginary unit p x is the period in the x direction, p y is the period in the y direction, m and j are the orders in the x direction, n and l are the orders in the y direction, k x =2π / p x , -p x / 2, t0, t1, t2, …, t γ-1 ,t γ 、p x / 2 are the x-coordinates of the target integral subintervals in the x-direction; k y =2π / p y , -p y / 2, s0, s1, s2, …, s e-1 、s e 、p y / 2 are the y coordinates of the target integral subinterval in the y direction, Representative Grid The x- and y-coordinates of the center point, Representative Grid The area of is the number of grids, m, n, j and l are integers, γ and e are natural numbers, Is a positive integer.

[0095] In order to verify the model established by the above method, the following uses the microstructures in the periodic medium to verify the prism, elliptical cone, and rotated elliptical cone.

[0096] Scene 1

[0097] Fig.10 (a) shows a side view of a microstructure that is a prism. Fig.10 (b) is a top view of a thin slice after the microstructure is layered into prisms. Fig.10 The gray area in (b) is the projection of the microstructured sheet on the xy plane of the periodic space, the outermost dashed box represents the periodic space, and the vertical dashed line shows the division of the target integral sub-interval in the x direction. Fig.10The parameters of the microstructure shown in (a) are prisms with the following characteristics: TCD_x: 60nm, prism TCD_Y: 30nm, prism BCD_x: 80nm, prism BCD_Y: 50nm, prism height: 100nm, number of layers: 10. After the optical property modeling is performed according to the above method, the theoretical spectrum calculation results are compared as shown in Table 1. The prior art evenly divides the integral interval into 256 intervals in both the X and Y directions, while the method of the present application divides the target integral sub-intervals into 3 in the X and Y directions, respectively. Thus, the amount of calculation for solving the Fourier coefficients of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium is greatly reduced, thereby improving the calculation efficiency of the theoretical spectrum. The prior art takes 58 seconds to obtain the theoretical spectrum, while the present application takes 46 seconds to obtain the theoretical spectrum. At the same time, the accuracy of the theoretical spectrum obtained by the method of the present application is improved by one order of magnitude compared with the accuracy of the theoretical spectrum obtained by the prior art. It can be seen that the method of the present application uses less time to obtain a more accurate theoretical spectrum, while improving the calculation efficiency and accuracy of the theoretical spectrum.

[0098] Table 1

[0099]

[0100] Scene 2

[0101] Fig.11 (a) shows a side view of the microstructure as an elliptical cone. Fig.11 (b) is a top view of a thin slice after the microstructure is layered into an elliptical cone. Fig.11 The gray area in (b) is the projection of the microstructured sheet on the xy plane of the periodic space, the outermost dashed box represents the periodic space, and the vertical dashed line shows the division of the target integral sub-interval. Fig.11The microstructure shown in (a) is an elliptical cone with the following parameters: the x-axis radius of the ellipse on the ellipse: 40nm, the y-axis radius of the ellipse on the ellipse: 30nm, the x-axis radius of the ellipse below the ellipse: 60nm, the y-axis radius of the ellipse below the ellipse: 50nm, the height of the ellipse: 100nm, and the number of layers: 10. After the optical property modeling is performed according to the above method, the comparison of the theoretical spectrum calculation results is shown in Table 2. The prior art evenly divides the integral interval into 256 intervals in both the X and Y directions, while the method of the present application divides the target integral sub-intervals into 87 in the X direction and 67 in the Y direction, thereby greatly reducing the amount of calculation for solving the Fourier coefficient of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium, thereby improving the calculation efficiency of the theoretical spectrum. The prior art takes 172 seconds to obtain the theoretical spectrum, while the present application takes 160 seconds to obtain the theoretical spectrum. At the same time, the accuracy of the theoretical spectrum obtained by the method of the present application is improved by one order of magnitude compared with the accuracy of the theoretical spectrum obtained by the prior art. It can be seen that the method of the present application uses less time to obtain a more accurate theoretical spectrum, while improving the calculation efficiency and accuracy of the theoretical spectrum.

[0102] Table 2

[0103]

[0104] Scene 3

[0105] Assume that the parameters of the rotating elliptical cone have the following characteristics: the x-axis radius of the ellipse on the elliptical cone: 40nm, the Y-axis radius of the ellipse on the elliptical cone: 30nm, the x-axis radius of the ellipse under the elliptical cone: 60nm, the Y-axis radius of the elliptical cone under the elliptical cone: 50nm, the rotation angle of the elliptical cone: 30 degrees, the height of the elliptical cone: 100nm, and the number of layers: 10. Fig.12It is a top view of a thin slice after the microstructure layering of the rotating elliptical table, and the gray area is the projection of the microstructure thin slice in the periodic space xy plane. The outermost dotted box represents the periodic space, and the vertical dotted line straight line presents the division of the integral interval. After the optical property modeling is performed according to the above method, the theoretical spectrum calculation results are compared as shown in Table 3. The prior art divides the integral interval uniformly, and 128 intervals are evenly divided in the X and Y directions, while the method of the present application is used to divide 101 target integral sub-intervals in X and 77 target integral sub-intervals in the Y direction, thereby greatly reducing the calculation amount of the Fourier coefficient of the dielectric coefficient of the periodic medium and the Toeplitz matrix of the dielectric coefficient of the periodic medium, thereby improving the calculation efficiency of the theoretical spectrum, the prior art obtains the theoretical spectrum consuming 176 seconds, and the present application obtains the theoretical spectrum consuming 160 seconds, and at the same time, the accuracy of the theoretical spectrum obtained by the method of the present application is improved by an order of magnitude than the accuracy of the theoretical spectrum obtained by the prior art, which shows that the method of the present application is used to obtain a more accurate theoretical spectrum in less time, while improving the calculation efficiency and calculation accuracy of the theoretical spectrum.

[0106] Table 3

[0107]

[0108]

[0109] Based on the above optical property modeling method, in some embodiments of the present application, the present application embodiment discloses an optical property modeling device, such as Fig.13 As shown, the device 1300 is used to implement the methods recorded in the above method embodiments, and includes: a division unit 1301, a calculation unit 1302 and a modeling unit 1303.

[0110] The division unit 1301 is used to divide the microstructure in the periodic medium into N layers of thin slices in the z direction; for the thin slices of the same layer of microstructure, the following processing is performed: the geometric information of each closed area projected by the thin slice on the xy plane of the periodic space is obtained; according to the geometric information, the periodic space is divided to obtain the target integral sub-interval divided in the x direction and the target integral sub-interval divided in the y direction.

[0111] The calculation unit 1302 is used to calculate the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium.

[0112] The modeling unit 1303 is used to perform rigorous coupled wave analysis using the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium to achieve optical property modeling of the periodic medium.

[0113] All relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0114] In other embodiments of the present application, the present application discloses an electronic device, such as Fig.14 As shown, the electronic device 1400 may include: one or more processors 1401; a memory 1402; a display 1403; one or more applications (not shown); and one or more computer programs 1404, and the above components may be connected via one or more communication buses 1405. The one or more computer programs 1404 are stored in the above memory 1402 and are configured to be executed by the one or more processors 1401, and the one or more computer programs 1404 include instructions.

[0115] The present application also provides a computer readable medium on which a computer program is stored, and when the computer program is executed by a computer, the method described in the above method embodiment is implemented. The specific effects can refer to the above embodiment.

[0116] The present application also provides a computer program product, which implements the method described in the above method embodiment when executed by a computer. The specific effects can refer to the above embodiment.

[0117] Through the description of the above implementation methods, technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device and unit described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0118] Each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0119] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as flash memory, mobile hard disk, read-only memory, random access memory, disk or optical disk.

[0120] The above is only a specific implementation of the embodiment of the present application, but the protection scope of the embodiment of the present application is not limited thereto, and any changes or replacements within the technical scope disclosed in the embodiment of the present application should be included in the protection scope of the embodiment of the present application. Therefore, the protection scope of the embodiment of the present application should be based on the protection scope of the claims.

Claims

1. An optical property modeling method, characterized in that: The method includes: The microstructure in the periodic medium is divided into N thin slices in the z direction, where N is a positive integer; For the slices of the same microstructure, the following processing is performed: Obtaining geometric information of each closed area of ​​the sheet projected on the periodic space xy plane; According to the geometric information, the periodic space is divided to obtain a target integral sub-interval divided in the x direction and a target integral sub-interval divided in the y direction; Calculate the Fourier coefficients of the dielectric constant of periodic media and the Toeplitz matrix of the dielectric constant of periodic media; Performing rigorous coupled wave analysis using the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium to achieve optical property modeling of the periodic medium; The step of obtaining geometric information of each closed area projected by the thin sheet on the periodic space xy plane includes: obtaining each closed area projected by the thin sheet on the periodic space xy plane, and expressing the boundaries of each closed area as each polygon; obtaining the x coordinate and y coordinate of each polygon vertex to form geometric information of each closed area, wherein the geometric information includes a set of x coordinates and a set of y coordinates; According to the geometric information, the periodic space is divided to obtain a target integral sub-interval divided in the x direction and a target integral sub-interval divided in the y direction, including: Arrange the coordinates in the set of x coordinates and the set of y coordinates in order from large to small or from small to large, respectively, and any two adjacent coordinates in the set of x coordinates and the set of y coordinates after the arrangement constitute a candidate integral subinterval; Determine whether the candidate integral subinterval is a non-uniform interval; obtain the length of the candidate integral subinterval; When the candidate integral subinterval is a non-uniform interval and the length of the candidate integral subinterval is greater than or equal to a preset step length, the candidate integral subinterval is divided into a plurality of target integral subintervals; otherwise, the candidate integral subinterval is taken as a target integral subinterval.

2. The method according to claim 1, characterized in that: The determining whether the candidate integral subinterval is a non-uniform interval comprises: Acquire a first reference boundary line and a second reference boundary line of a candidate integral subinterval formed by the two adjacent coordinates in the x direction, wherein the first reference boundary line and the second reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the first reference boundary line and the second reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval; Obtaining the number h of first boundary intersection points formed by the intersection of the first reference boundary line and the polygon, and the number k of second boundary intersection points formed by the intersection of the second reference boundary line and the polygon; When h is not equal to k, the candidate integral subinterval is taken as a non-uniform interval; or, when h is equal to k and not equal to zero, the y coordinate of the first boundary intersection point is obtained. , and the y coordinate of the second boundary intersection point , wherein the y coordinates of the h boundary intersection points and the y coordinates of the k boundary intersection points are arranged in order from large to small or from small to large; and is greater than or equal to a threshold, the candidate integral subinterval is regarded as a non-uniform interval; When h is equal to k and equal to zero, the candidate integral subinterval is taken as a uniform interval; Or, when h is equal to k and not equal to zero, and If the value is smaller than the threshold, the candidate integral subinterval is taken as a uniform interval.

3. The method according to claim 1 or 2, characterized in that: The determining whether the candidate integral subinterval is a non-uniform interval comprises: Acquire a third reference boundary line and a fourth reference boundary line of the candidate integral subinterval formed by the two adjacent coordinates in the y direction, wherein the third reference boundary line and the fourth reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the third reference boundary line and the fourth reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval; Obtaining the number u of third boundary intersection points formed by the intersection of the third reference boundary line and the polygon, and the number v of fourth boundary intersection points formed by the intersection of the fourth reference boundary line and the polygon; When u is not equal to v, the candidate integral subinterval is taken as a non-uniform interval; or, when u is equal to v and not equal to zero, the x coordinate of the third boundary intersection is obtained. , and the x-coordinate of the fourth boundary intersection point , where the x-coordinates of u boundary intersection points and the x-coordinates of v boundary intersection points are arranged in order from large to small or from small to large; and is greater than or equal to a set threshold, the candidate integral subinterval is regarded as a non-uniform interval; When u is equal to v and equal to zero, the candidate integral subinterval is taken as a uniform interval; Or, when u is equal to v and not equal to zero, and If the candidate integral sub-interval is smaller than the set threshold, the candidate integral sub-interval is taken as a uniform interval.

4. An optical property modeling device, characterized in that: The device includes: A division unit is used to divide the microstructure in the periodic medium into N layers of thin slices in the z direction; for thin slices of the same layer of microstructure, the following processing is performed: geometric information of each closed area projected by the thin slice on the xy plane of the periodic space is obtained; according to the geometric information, the periodic space is divided to obtain the target integral sub-interval divided in the x direction and the target integral sub-interval divided in the y direction; A calculation unit, used for calculating the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium; A modeling unit, used for performing a rigorous coupled wave analysis using the Fourier coefficient of the dielectric constant of the periodic medium and the Toeplitz matrix of the dielectric constant of the periodic medium, so as to achieve optical property modeling of the periodic medium; When obtaining geometric information of each closed area projected by the thin sheet on the periodic space xy plane, the division unit is specifically used to: obtain each closed area projected by the thin sheet on the periodic space xy plane, and represent the boundaries of each closed area as each polygon; obtain the x coordinate and y coordinate of each polygon vertex to form geometric information of each closed area, wherein the geometric information includes a set of x coordinates and a set of y coordinates; When the division unit divides the periodic space according to the geometric information to obtain the target integral sub-interval divided in the x direction and the integral sub-interval divided in the y direction, it is specifically used to: Arrange the coordinates in the x-coordinate set and the y-coordinate set in order from large to small or from small to large, respectively, and any two adjacent coordinates in the x-coordinate set and the y-coordinate set after the order is arranged constitute a candidate integral subinterval; Determine whether the candidate integral subinterval is a non-uniform interval; obtain the length of the candidate integral subinterval; When the candidate integral subinterval is a non-uniform interval and the length of the candidate integral subinterval is greater than or equal to a preset step length, the candidate integral subinterval is divided into a plurality of target integral subintervals; otherwise, the candidate integral subinterval is taken as a target integral subinterval.

5. The device according to claim 4, characterized in that When determining whether the candidate integral subinterval is a non-uniform interval, the dividing unit is specifically used to: Acquire a first reference boundary line and a second reference boundary line of a candidate integral subinterval formed by the two adjacent coordinates in the x direction, wherein the first reference boundary line and the second reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the first reference boundary line and the second reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval; Obtaining the number h of first boundary intersection points formed by the intersection of the first reference boundary line and the polygon, and the number k of second boundary intersection points formed by the intersection of the second reference boundary line and the polygon; When h is not equal to k, the candidate integral subinterval is regarded as a non-uniform interval; Or, when h is equal to k and not equal to zero, obtain the y coordinate of the first boundary intersection point , and the y coordinate of the second boundary intersection point , wherein the y coordinates of the h boundary intersection points and the y coordinates of the k boundary intersection points are arranged in order from large to small or from small to large; and is greater than or equal to a threshold, the candidate integral subinterval is regarded as a non-uniform interval; When h is equal to k and equal to zero, the candidate integral subinterval is taken as a uniform interval; Or, when h is equal to k and not equal to zero, and If the value is smaller than the threshold, the candidate integral subinterval is taken as a uniform interval.

6. The device according to claim 4 or 5, characterized in that When determining whether the candidate integral subinterval is a non-uniform interval, the dividing unit is specifically used to: Acquire a third reference boundary line and a fourth reference boundary line of the candidate integral subinterval formed by the two adjacent coordinates in the y direction, wherein the third reference boundary line and the fourth reference boundary line are non-overlapping straight lines perpendicular to the candidate integral subinterval, and intersection points of the third reference boundary line and the fourth reference boundary line with the candidate integral subinterval are not endpoints of the candidate integral subinterval; Obtaining the number u of third boundary intersection points formed by the intersection of the third reference boundary line and the polygon, and the number v of fourth boundary intersection points formed by the intersection of the fourth reference boundary line and the polygon; When u is not equal to v, the candidate integral subinterval is regarded as a non-uniform interval; Or, when u is equal to v and not equal to zero, obtain the x coordinate of the third boundary intersection point , and the x-coordinate of the fourth boundary intersection point , where the x-coordinates of u boundary intersection points and the x-coordinates of v boundary intersection points are arranged in order from large to small or from small to large; and is greater than or equal to a set threshold, the candidate integral subinterval is regarded as a non-uniform interval; When u is equal to v and equal to zero, the candidate integral subinterval is taken as a uniform interval; Or, when u is equal to v and not equal to zero, and If the candidate integral sub-interval is smaller than the set threshold, the candidate integral sub-interval is taken as a uniform interval.

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