Method and Apparatus for Multi-Segment Alignment Correction of Exposure Patterns Based on a Guide Matrix

Abstract

According to the present invention, by extracting a plurality of reference guide points from design data or pattern data corresponding to an exposure target pattern and configuring them into a reference guide matrix in the form of a matrix, position correction of the exposure pattern can be performed on a basis of a plurality of divided guide areas rather than on a basis of a single reference point or the entire area. Accordingly, there is an effect of more precisely correcting non-uniform positional distortion occurring in large-area substrates. Furthermore, according to the present invention, by configuring a measurement guide matrix corresponding to the reference guide matrix using a plurality of measurement guide points measured from an actual substrate or exposure equipment, and by aligning the reference guide matrix and the measurement guide matrix with each other, local positional deviations caused by substrate deformation, stage error, optical distortion, alignment error, etc., can be reflected on a region-by-region basis. Accordingly, high overlay precision and pattern matching can be secured compared to a method of applying the same correction value to the entire pattern.

Description

Technology Field

[0001] The present invention relates to an alignment correction technology for digital exposure equipment, and more specifically, to a guide matrix-based multi-division alignment correction method and apparatus for an exposure pattern, wherein a plurality of guide points set on an exposure target pattern or substrate are configured in a matrix form, and positional distortion of the exposure pattern is corrected for each divided region based on the guide points. Background Technology

[0002] Recently, manufacturing processes for semiconductor packaging, panel interposers, glass substrates, high-multilayer PCBs, and display substrates have simultaneously demanded the miniaturization of circuit patterns and the expansion of substrate areas. In particular, advanced packaging processes such as HBM, Chiplets, RDL (Re-Distribution Layer), and Panel Level Packaging require the precise formation of fine patterns of several micrometers or less on large-area substrates; therefore, pattern positional alignment and overlay precision during the photolithography process play a critical role. In these digital photolithography processes, various positional errors can occur during the process of forming exposure patterns corresponding to design data on the substrate. For example, the reference coordinates in the design data may not match the corresponding coordinates on the actual exposure target substrate due to factors such as substrate warping, thermal deformation, internal stage movement errors, optical system distortion, lens magnification deviations, substrate mounting errors, and alignment errors. Particularly in the case of large-area substrates, these errors often occur locally with different directions and magnitudes depending on the location or area of ​​the substrate, rather than occurring uniformly across the entire surface.

[0003] In conventional digital exposure equipment, to correct such positional errors, a block shift method was mainly used, in which a already generated bitmap image or exposure image data is divided into blocks of a certain size and each block is moved in a predetermined direction. However, because the correction unit of the block shift method is limited to the block unit, it is difficult to accurately reflect local distortions that change continuously within the block. In addition, if the amount of movement differs between adjacent blocks, discontinuities in the pattern, step heights, or stitching defects may occur at the block boundaries.

[0004] Furthermore, conventional bitmap-based correction methods are structured to perform correction via post-processing after generating pattern data in image form; consequently, in high-resolution and large-area exposure environments, there are issues such as a rapid increase in data volume, memory usage, and data transmission volume. Consequently, there are limitations in reflecting correction values ​​in real-time at the time of exposure or adaptively reconstructing the exposure pattern based on the local deformation state of the substrate.

[0005] Meanwhile, deformation of a large-area substrate is difficult to explain solely by positional error of a specific point, and it has the characteristic of being deformed in a form where multiple reference points on the substrate are interconnected. That is, since the bending or stage distortion of the substrate can exhibit continuous deformation characteristics between adjacent regions, it is difficult to sufficiently correct positional distortion in each region using an overall correction method that utilizes only a single alignment key or a single reference mark. In particular, for exposure targets with a large area, such as panel interposers or glass substrates, different distortion patterns appear depending on the position of the substrate; therefore, it is necessary to divide the substrate or pattern area into multiple segmented regions based on multiple reference points and calculate correction coordinates for each segmented region.

[0006] However, in conventional technology, when alignment keys or reference marks included in design data are not arranged in a consistent matrix structure, there was a problem in that it is difficult to systematically construct a correction area using these reference points and to reliably track the correspondence between the measured alignment keys and the reference points in the design data. Furthermore, a precise multi-segment correction structure has not been sufficiently proposed that generates a reference guide from arbitrarily placed alignment keys or pattern reference points, constructs a measurement guide from actual measured guide points, and then calculates correction coordinates using the relative positional relationship between them.

[0007] Accordingly, a technology is required to configure a plurality of guide points set on an exposure target pattern or substrate into a guide matrix in the form of a matrix, determine a divided guide area where the correction target coordinates are located by correlating a reference guide matrix and a measurement guide matrix, and calculate correction coordinates on the measurement guide using the relative position that the coordinates have within the divided guide area.

[0008] In addition, a guide matrix-based multi-segment alignment correction technology is required that can continuously and precisely correct local positional distortions caused by substrate deformation, stage error, optical distortion, and alignment error by calculating the aspect ratio and aspect ratio of the correction target coordinates in each segmented guide area and applying them to the corresponding area of ​​the measurement guide matrix to calculate interpolated correction coordinates. Prior art literature

[0009] Korean Patent Publication No. 10-2025-0066122 (May 13, 2025) The problem to be solved

[0010] The present invention aims to solve the problems of the aforementioned prior art by providing a guide matrix-based exposure pattern multi-segment alignment correction method and apparatus that can perform position correction of an exposure pattern in units of multiple segmented regions by extracting a plurality of reference guide points from design data or pattern data corresponding to an exposure target pattern and configuring them into a reference guide matrix in the form of a matrix.

[0011] In addition, the present invention aims to provide an exposure pattern alignment correction technology capable of precisely correcting local positional distortions caused by substrate deformation, stage error, optical distortion, alignment error, etc., on a regional basis by configuring a plurality of measurement guide points actually measured on an exposure target substrate or exposure equipment into a measurement guide matrix corresponding to the matrix structure of a reference guide matrix, and by making the reference guide matrix and the measurement guide matrix correspond to each other.

[0012] In addition, the present invention aims to provide an exposure pattern correction technology capable of precisely reflecting non-uniform deformation of a large-area substrate that is difficult to correct using a single reference point or a whole-area reference correction method, by determining a segmented guide area where the correction target coordinates are located and calculating correction coordinates by applying the relative position of the correction target coordinates within the segmented guide area to a measurement guide matrix.

[0013] In addition, the present invention aims to provide an exposure pattern multi-segment alignment correction technology capable of continuously correcting positional changes within a segmented area without boundary discontinuities caused by block-unit movement by calculating the horizontal and vertical ratios of the coordinates to be corrected, applying the horizontal and vertical ratios to a corresponding measurement guide to generate interpolation lines, and then calculating the intersection points of the interpolation lines as correction coordinates.

[0014] In addition, the present invention aims to provide a universal alignment correction technology that enables the configuration of a reference guide matrix and a measurement guide matrix even for various exposure target patterns in which the guide points are not arranged in a standardized matrix structure, by utilizing alignment keys, reference marks, pattern outer points, pattern inner points, or user-defined reference points included in design data as reference guide points.

[0015] In addition, the present invention aims to provide an exposure pattern correction method and apparatus capable of ensuring precise exposure pattern alignment in real-time or near-real-time even in high-resolution and large-area digital exposure processes by generating corrected polygon vector data, exposure bitmap data, or frame data for a digital micromirror device based on correction coordinates calculated for each divided guide area.

[0016] Meanwhile, the technical problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by a person skilled in the art from the description below. means of solving the problem

[0017] A guide matrix-based exposure pattern multi-segment alignment correction device according to the present disclosure for achieving the above-described technical problem comprises: a reference guide point extraction unit that extracts a plurality of reference guide points from design data corresponding to an exposure target pattern or pattern data generated from said design data; a reference guide matrix generation unit that generates a reference guide matrix including a plurality of reference guides by arranging the plurality of reference guide points in a matrix form; a measurement guide matrix generation unit that generates a measurement guide matrix including a plurality of measurement guides based on a plurality of measurement guide points measured from an exposure target substrate or an exposure equipment; a segmentation area determination unit that determines a segmentation guide area where the correction target coordinates of the exposure target pattern are located by aligning the reference guide matrix and the measurement guide matrix with each other; and a correction coordinate calculation unit that calculates a correction coordinate corresponding to the correction target coordinate by applying the relative position that the correction target coordinates have within the segmentation guide area to the measurement guide matrix, wherein the correction coordinate calculation unit can correct the positional distortion of the exposure target pattern by area by calculating the correction coordinates in units of the segmentation guide area. Effects of the invention

[0018] According to the present invention, by extracting a plurality of reference guide points from design data or pattern data corresponding to an exposure target pattern and configuring them into a reference guide matrix in the form of a matrix, position correction of the exposure pattern can be performed not based on a single reference point or the entire area, but on a plurality of divided guide area units. Accordingly, there is an effect of more precisely correcting non-uniform positional distortion occurring on a large-area substrate.

[0019] Furthermore, according to the present invention, a plurality of measurement guide points measured on an actual substrate or exposure equipment are configured into a measurement guide matrix corresponding to a reference guide matrix, and by aligning the reference guide matrix and the measurement guide matrix with each other, local positional deviations caused by substrate deformation, stage error, optical distortion, alignment error, etc., can be reflected on a regional basis. Accordingly, high overlay precision and pattern alignment can be secured compared to a method that applies the same correction value to the entire pattern.

[0020] In addition, according to the present invention, a segmented guide area where a coordinate to be corrected is located is determined, and a correction coordinate on a measurement guide matrix can be calculated using the horizontal and vertical ratios of the coordinate to be corrected within the segmented guide area. Accordingly, the position of the coordinate to be corrected is not simply corrected by the amount of movement, but can be continuously interpolated and corrected based on the relative positional relationship within the segmented area.

[0021] In addition, according to the present invention, a first interpolation line is calculated between a first measurement side and a second measurement side of a corresponding measurement guide based on a horizontal ratio, and a second interpolation line is calculated between a third measurement side and a fourth measurement side based on a vertical ratio, and then the intersection point of the first interpolation line and the second interpolation line can be calculated as a correction coordinate. Accordingly, discontinuities in block boundaries, pattern step differences, or stitching defects that may occur in a block unit movement method can be mitigated or prevented.

[0022] Furthermore, according to the present invention, since at least one of an alignment key, a reference mark, a pattern outer point, a pattern inner point, and a user-defined reference point can be used as a reference guide point, it can be applied not only to a substrate having a standardized alignment key array but also to various design data or exposure target patterns including irregularly arranged reference points. Accordingly, the universality of application to equipment or process conditions is improved.

[0023] In addition, according to the present invention, correction coordinates for each divided guide region can be calculated using a reference guide matrix and a measurement guide matrix, and based on this, corrected polygon vector data, bitmap data for exposure, or frame data for a digital micromirror device can be generated. Accordingly, the results of calculating the correction coordinates can be directly reflected in the actual exposure data generation process, and there is an effect that enables precise pattern formation in a high-resolution digital exposure process.

[0024] In addition, according to the present invention, complex positional distortions caused by different causes, such as substrate warping, thermal deformation, stage movement error, optical system distortion, and alignment error, can be integrated and corrected using a guide matrix-based segmented area structure. Accordingly, high-precision exposure quality required in large-area panel interposers, glass substrates, high-multilayer substrates, and fine redistribution processes can be reliably secured.

[0025] In addition, according to the present invention, since local distortion of the exposure pattern can be corrected region by region while maintaining continuity between adjacent guide regions, the correction quality is improved compared to the conventional bitmap-based block shift method, the exposure defect rate is reduced, and production yield and process stability can be improved.

[0026] The effects obtainable from the exemplary embodiments of the present disclosure are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the description below. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure. Brief explanation of the drawing

[0027] FIG. 1 is a block diagram showing the schematic configuration of a guide matrix-based exposure pattern multi-segment alignment correction device according to one embodiment of the present invention. FIG. 2 is a timing diagram illustrating the concept of ns-unit delay correction parameters and phase alignment logic according to one embodiment of the present invention. FIG. 3 is a diagram showing an example of constructing a multi-head exposure system according to one embodiment of the present invention. Figure 4 is a diagram showing an exposure pattern image with stitching errors occurring before timing correction or phase alignment correction is applied in a multi-head exposure system. FIG. 5 is a diagram showing an exposure pattern image after DB-based timing correction according to one embodiment of the present invention. Specific details for implementing the invention

[0028] Hereinafter, various embodiments of the present disclosure are described in conjunction with the accompanying drawings. As various embodiments of the present disclosure may be subject to various modifications and may have various forms, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the various embodiments of the present disclosure to specific forms, and it should be understood that they include all modifications and / or equivalents and substitutions that fall within the spirit and scope of the various embodiments of the present disclosure. In relation to the description of the drawings, similar reference numerals have been used for similar components.

[0029] In various embodiments of the present disclosure, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0030] In various embodiments of the present disclosure, expressions such as “or” include any and all combinations of the words listed together. For example, “A or B” may include A, may include B, or may include both A and B.

[0031] Expressions such as "first," "second," "first," or "second" used in various embodiments of the present disclosure may modify various components of the various embodiments, but do not limit such components. For example, such expressions do not limit the order and / or importance of such components and may be used to distinguish one component from another.

[0032] When it is mentioned that a component is "connected" or "joined" to another component, it should be understood that the component may be directly connected or joined to the other component, but that a new component may also exist between the component and the other component.

[0033] In the embodiments of the present disclosure, terms such as "module," "unit," "part," etc. are used to refer to a component that performs at least one function or operation, and such component may be implemented in hardware or software, or in a combination of hardware and software. Additionally, a plurality of "modules," "units," "parts," etc. may be integrated into at least one module or chip and implemented as at least one processor, except where each needs to be implemented in specific individual hardware.

[0034] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the various embodiments of the present disclosure.

[0035] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0036] FIG. 1 is a block diagram showing the schematic configuration of a guide matrix-based exposure pattern multi-segment alignment correction device according to an embodiment of the present invention. Referring to FIG. 1, the guide matrix-based exposure pattern multi-segment alignment correction device (100) according to an embodiment of the present invention may include a reference guide point extraction unit (110), a reference guide matrix generation unit (120), a measurement guide matrix generation unit (130), a segmentation area determination unit (140), and a correction coordinate calculation unit (150). Input data may include design data corresponding to an exposure target pattern or pattern data generated from said design data. For example, the design data may be drawing data in the format of GDS II, OASIS, or Gerber, and the pattern data may be polygon vector data, raster data, or intermediate pattern data converted from said design data into a form that can be processed by an exposure device.

[0037] The reference guide point extraction unit (110) can extract a plurality of reference guide points from design data or pattern data corresponding to the exposure target pattern. Here, a reference guide point may refer to a point that can be used as a reference coordinate on the design data and may include at least one of an alignment key, a reference mark, a pattern outer point, a pattern inner point, or a user-defined reference point. By extracting a plurality of reference guide points from the design reference coordinate system, the reference guide point extraction unit (110) can define a reference position of the exposure target pattern during a subsequent correction process.

[0038] The reference guide matrix generation unit (120) can generate a reference guide matrix by arranging a plurality of reference guide points extracted by the reference guide point extraction unit (110) in a matrix form. The reference guide matrix may have an M×N matrix structure and may include a plurality of reference guide points arranged in the row direction and the column direction. Additionally, the reference guide matrix generation unit (120) can define a single reference guide using a plurality of adjacent reference guide points, for example, four reference guide points. Accordingly, the reference guide matrix may be configured as a divided area structure containing a plurality of reference guides.

[0039] The measurement guide matrix generation unit (130) can generate a measurement guide matrix based on a plurality of measurement guide points measured on an exposure target substrate or an exposure device. The measurement guide points may be points corresponding to alignment keys, reference marks, or reference positions measured by the exposure device formed on the actual substrate. The measurement guide matrix generation unit (130) can arrange the plurality of measurement guide points to correspond to the matrix structure of a reference guide matrix, and accordingly, can generate a measurement guide matrix with an M×N matrix structure that is identical to or corresponding to the reference guide matrix.

[0040] In this case, the reference guide matrix can represent the ideal reference position based on the design data, and the measurement guide matrix can represent the reference position after deformation measured on the actual substrate or exposure equipment. Therefore, the difference between the reference guide matrix and the measurement guide matrix may reflect positional distortion caused by substrate deformation, stage error, optical distortion, magnification error, or alignment error.

[0041] The division area determination unit (140) can determine a division guide area where the correction target coordinates of the exposure target pattern are located by aligning the reference guide matrix and the measurement guide matrix with each other. For example, if the correction target coordinate P is located in a specific reference guide area of ​​the reference guide matrix, the division area determination unit (140) can determine the corresponding reference guide area as the division guide area of ​​the correction target coordinate P. At this time, the division guide area can be specified by matrix indices i and j, and, for example, may be an area enclosed by reference guide points (i, j), (i, j+1), (i+1, j), and (i+1, j+1).

[0042] The correction coordinate calculation unit (150) can calculate the relative position that the correction target coordinate has within the divided guide area and apply the relative position to the corresponding measurement guide area of ​​the measurement guide matrix to calculate the correction coordinate corresponding to the correction target coordinate. Specifically, the correction coordinate calculation unit (150) can calculate the horizontal ratio that the correction target coordinate P has in the first direction and the vertical ratio that it has in the second direction within the reference guide area. Here, the horizontal ratio may be the relative position ratio that the correction target coordinate P occupies within the horizontal width of the reference guide area, and the vertical ratio may be the relative position ratio that the correction target coordinate P occupies within the vertical height of the reference guide area.

[0043] For example, if the width of the reference guide area is Wr and the height is Hr, and the relative positions of the coordinates P to be corrected within the reference guide area are x and y, the correction coordinate calculation unit (150) can calculate the width ratio u=x / Wr and the height ratio v=y / Hr. At this time, u and v can have values ​​greater than or equal to 0 and less than or equal to 1, and can indicate where the coordinates P to be corrected exist within the reference guide area.

[0044] The correction coordinate calculation unit (150) can apply the calculated horizontal ratio u and vertical ratio v to the corresponding measurement guide area of ​​the measurement guide matrix. For example, if the measurement guide area is defined by four measurement guide points A′(i, j), B′(i, j+1), C′(i+1, j), and D′(i+1, j+1), the correction coordinate calculation unit (150) can calculate corresponding points on the upper measurement side A′B′ and the lower measurement side C′D′, respectively, using the horizontal ratio u. Additionally, the correction coordinate calculation unit (150) can calculate a correction coordinate P′ corresponding to the correction target coordinate P between the corresponding points using the vertical ratio v.

[0045] In one embodiment, the correction coordinate calculation unit (150) can calculate the correction coordinate P′ using the following interpolation operation. First, based on the horizontal ratio u, the point E′ on the upper measurement side A′B′ and the point F′ on the lower measurement side C′D′ can be calculated. For example, E′ can be calculated as A′+u×(B′-A′), and F′ can be calculated as C′+u×(D′-C′). Subsequently, based on the vertical ratio v, the correction coordinate calculation unit (150) can calculate the point on the interpolation line connecting E′ and F′ as the correction coordinate P′. For example, the correction coordinate P′ can be calculated as E′+v×(F′-E′). Accordingly, the correction coordinate calculation unit (150) can convert the correction target coordinate to a position corresponding to the measurement guide matrix while maintaining the relative position the correction target coordinate has within the divided guide area, rather than simply moving the correction target coordinate in a certain direction. Therefore, substrate deformation or positional distortion occurring in each segmented guide area can be locally reflected, and more continuous correction is possible even between adjacent segmented areas.

[0046] In addition, the correction coordinate calculation unit (150) can calculate the correction target coordinates for all divided guide areas as illustrated in FIG. 1. That is, for each of the multiple coordinates or multiple pattern elements constituting the exposure target pattern, the divided guide area where the corresponding coordinate is located is determined, and the correction coordinates can be calculated using the measurement guide area corresponding to each divided guide area. Accordingly, the entire coordinate system of the exposure target pattern can be corrected by area based on the measurement guide matrix. In this way, the guide matrix-based exposure pattern multi-divided alignment correction device (100) according to one embodiment of the present invention can correct the position distortion of the exposure target pattern on a divided guide area basis by aligning the reference guide matrix based on design data with the measurement guide matrix based on actual measurement standards and calculating the correction coordinates using the relative position within the divided area of ​​the correction target coordinates. Accordingly, the present invention can precisely reflect localized substrate deformation, stage error, optical distortion, and alignment error occurring on a large-area substrate by region, mitigate boundary discontinuities or pattern step differences that may occur in conventional block shift methods, and improve overlay precision and pattern alignment required in high-resolution digital exposure processes.

[0047] The reference guide point extraction unit (110) extracts at least one of the alignment key, reference mark, pattern outer point, pattern inner point, and user-defined reference point included in the design data as the plurality of reference guide points. In one embodiment, the reference guide point extraction unit (110) can extract at least one of the alignment key, reference mark, pattern outer point, pattern inner point, and user-defined reference point included in the design data as the plurality of reference guide points.

[0048] Here, the design data may be data containing shape, position, size, and arrangement information of the exposure target pattern, and may be, for example, a GDS II, OASIS, Gerber, or an equivalent circuit pattern design file. The reference guide point extraction unit (110) searches for reference coordinates that can be used to correct the position of the exposure pattern from the design data, and can determine a plurality of points among the searched reference coordinates that are suitable for generating a guide matrix as reference guide points.

[0049] For example, the reference guide point extraction unit (110) can extract an alignment key included in the design data as a reference guide point. The alignment key may be an alignment mark predefined in the design data to check the alignment state between the exposure target substrate and the exposure pattern, and the reference guide point extraction unit (110) can extract a center point, vertex, intersection point, or specific corner point of the alignment key as a reference guide point.

[0050] As another example, the reference guide point extraction unit (110) can extract a reference mark included in the design data as a reference guide point. The reference mark may be a reference shape for determining the position, direction, or magnification of the exposure pattern, and the reference guide point extraction unit (110) can extract the center coordinates, outer coordinates, or multiple feature points constituting the reference mark as reference guide points.

[0051] As another example, the reference guide point extraction unit (110) can extract an outer point or an inner point of the exposure target pattern as a reference guide point. The pattern outer point may be a feature point of the outer boundary, corner, leading edge, bend, or closed curve of the exposure target pattern, and the pattern inner point may be a hole, intersection, branching point, center point, or a point of characteristic shape change formed inside the pattern. Accordingly, even if a separate alignment key or reference mark is not sufficiently placed on the design data, a reference guide point can be set using the geometric features of the pattern itself.

[0052] As another example, the reference guide point extraction unit (110) can extract a reference point designated by the user as a reference guide point. The user-designated reference point may be designated in correspondence with an important area of ​​the exposure target pattern, an area requiring correction precision, a stitching boundary, a panel edge area, or a location requiring process management. The reference guide point extraction unit (110) can receive the coordinates of the user-designated reference point from the user interface, recipe data, or process condition data and register them as a reference guide point.

[0053] The reference guide point extraction unit (110) may extract reference guide points using only one of the alignment key, reference mark, pattern outer point, pattern inner point, and user-defined reference point, or may extract reference guide points by combining two or more of these points. For example, the reference guide point extraction unit (110) may improve the distribution density and correction precision of reference guide points by primarily using the alignment key or reference mark in the outer area of ​​the substrate and additionally using the pattern inner point or user-defined reference point in the inner area where the pattern density is high.

[0054] Additionally, the reference guide point extraction unit (110) may perform at least one of the following preprocessing steps on the extracted multiple reference guide points: removing duplicate coordinates, aligning coordinates, assigning matrix indices, validating, or correcting spacing. For example, if multiple reference points that are close to each other are determined to be the same guide point, the reference guide point extraction unit (110) may select one of them as a representative reference guide point or calculate an average coordinate and set it as a representative reference guide point. In this way, since the reference guide point extraction unit (110) can utilize various reference elements included in the design data as reference guide points, it is possible to reliably secure basic coordinates for generating a reference guide matrix not only for design data with a standardized alignment key array but also for design data with an irregular pattern structure or uneven reference point arrangement.

[0055] Additionally, the reference guide matrix generation unit (120) defines a reference guide using at least four adjacent reference guide points among the plurality of reference guide points, and generates the reference guide matrix by arranging the plurality of reference guides in row and column directions. In one embodiment, the reference guide matrix generation unit (120) may define a reference guide using at least four adjacent reference guide points among the plurality of reference guide points extracted by the reference guide point extraction unit (110).

[0056] Here, the reference guide may refer to a unit area that serves as a correction standard for the exposure target pattern, and may correspond to a divided guide area defined in a reference coordinate system in the design data. For example, the reference guide matrix generating unit (120) may set four reference guide points, namely the first reference guide point, the second reference guide point, the third reference guide point, and the fourth reference guide point, which are arranged adjacent to each other in the row and column directions, as vertices of a single reference guide.

[0057] Specifically, the reference guide matrix generating unit (120) can assign matrix indices to multiple reference guide points. For example, when reference guide points are arranged in M ​​columns and N rows, the reference guide matrix generating unit (120) can assign an index (i, j) to each reference guide point. Here, i may be a row-direction index and j may be a column-direction index.

[0058] In this case, the reference guide matrix generating unit (120) can define a reference guide using four adjacent reference guide points, for example, reference guide points R(i, j), R(i, j+1), R(i+1, j), and R(i+1, j+1). The reference guide can be defined as a rectangular or quadrilateral area enclosed by the four reference guide points and can be used as a reference area for determining the segmented guide area where the correction target coordinates are located.

[0059] However, the reference guide is not necessarily limited to a rectangular shape and may be defined in the shape of a parallelogram, trapezoid, or irregular quadrilateral depending on the substrate deformation, the arrangement of the design pattern, or the positional relationship of the guide points. That is, the reference guide matrix generating unit (120) can define a closed area according to the actual coordinate relationship of four reference guide points and set the closed area as a reference guide.

[0060] Additionally, the reference guide matrix generation unit (120) can generate a reference guide matrix by arranging a plurality of reference guides defined as above in the row direction and column direction. For example, if there are M×N reference guide points, a reference guide consisting of four adjacent reference guide points can be repeatedly defined in the row direction and column direction, and accordingly, a plurality of reference guides can be arranged in a grid structure or a matrix structure.

[0061] In one embodiment, the reference guide matrix generating unit (120) may define a plurality of reference guides between reference guide points located in the first row and the second row, and define another plurality of reference guides between reference guide points located in the second row and the third row. In this way, the reference guide matrix generating unit (120) may divide the entire area of ​​the exposure target pattern or a part area requiring correction into a plurality of divided guide areas.

[0062] The reference guide matrix generating unit (120) can generate a reference guide matrix not only when multiple reference guide points are arranged at uniform intervals, but also when they are arranged at different intervals. For example, even when the interval between the first row and the second row is different from the interval between the second row and the third row, or when the interval between the first column and the second column is different from the interval between the second column and the third column, the reference guide matrix generating unit (120) can define each reference guide based on the coordinates of the actual reference guide points.

[0063] Additionally, the reference guide matrix generation unit (120) can determine the adjacent relationship by analyzing the arrangement state of multiple reference guide points. For example, the reference guide matrix generation unit (120) can define a reference guide by performing alignment based on the x-coordinates and y-coordinates of the reference guide points, grouping the reference guide points belonging to the same row or the same column, and connecting the reference guide points that are adjacent to each other in the row direction and column direction.

[0064] Additionally, the reference guide matrix generation unit (120) can determine the validity of the reference guide. For example, if the area of ​​the region defined by four reference guide points is smaller than a preset standard value, or if the side length or angle of the reference guide is abnormal, the reference guide can be determined as an invalid reference guide and excluded from correction or merged with an adjacent reference guide.

[0065] The reference guide matrix generated in this manner can represent an ideal arrangement of guide areas based on design data. Accordingly, it can be used as reference information for determining a segmented guide area where the correction target coordinates are located, corresponding to the measurement guide matrix in a subsequent step, and for calculating correction coordinates using the relative position within the segmented guide area. Accordingly, the reference guide matrix generation unit (120) of the present invention can systematically divide the entire area of ​​the exposure target pattern into a plurality of reference guides and provide a basis for correcting positional distortion for each segmented area.

[0066] Additionally, the measurement guide matrix generating unit (130) calculates the plurality of measurement guide points based on the actual measurement positions of the alignment key or reference mark formed on the substrate to be exposed, and generates the measurement guide matrix by arranging the plurality of measurement guide points to correspond to the matrix structure of the reference guide matrix. In one embodiment, the measurement guide matrix generating unit (130) may calculate the plurality of measurement guide points based on the actual measurement positions of the alignment key or reference mark formed on the substrate to be exposed.

[0067] Here, the measurement guide point may be actual location information corresponding to a reference guide point in the design data. For example, the measurement guide point may be an alignment key pre-formed on the substrate to be exposed, a reference mark, a feature point of a pattern formed in a previous process, or the actual measurement coordinates of a reference shape recognizable by the measurement unit of the exposure equipment.

[0068] The measurement guide matrix generation unit (130) can capture or detect an alignment key or reference mark on an exposure target substrate through an alignment measurement unit equipped in a camera, microscope, optical sensor, vision inspection device, or exposure equipment. Subsequently, the measurement guide matrix generation unit (130) can analyze the captured image or detection signal to extract a center point, vertex, intersection point, outer point, or feature point of the alignment key or reference mark, and calculate the extracted actual position coordinates as a measurement guide point.

[0069] For example, if a reference guide point R(i, j) exists in the design data and a corresponding alignment key or reference mark is measured on the substrate to be exposed, the measurement guide matrix generation unit (130) can set the actual measurement coordinates of the alignment key or reference mark as the measurement guide point M(i, j). At this time, the actual measurement coordinates can be expressed in any one of the substrate coordinate system, stage coordinate system, equipment coordinate system, or exposure coordinate system, and can be converted into a coordinate system corresponding to the reference guide matrix through coordinate transformation as needed.

[0070] Additionally, the measurement guide matrix generating unit (130) can arrange multiple measurement guide points to correspond to the matrix structure of the reference guide matrix. That is, the measurement guide matrix generating unit (130) can assign matrix indices to multiple measurement guide points that are identical to or correspond to the matrix indices of the reference guide points included in the reference guide matrix. For example, the actual measurement location corresponding to reference guide point R(i, j) can be arranged as measurement guide point M(i, j), and the actual measurement location corresponding to reference guide point R(i, j+1) can be arranged as measurement guide point M(i, j+1).

[0071] Accordingly, the measurement guide matrix generation unit (130) can generate a measurement guide matrix by arranging a plurality of measurement guide points in the row direction and the column direction. The measurement guide matrix may have the same matrix size as the reference guide matrix or a corresponding matrix structure, and each measurement guide point may be mapped to a corresponding reference guide point of the reference guide matrix.

[0072] In one embodiment, the measurement guide matrix generation unit (130) can generate a measurement guide matrix of an M×N structure corresponding to the matrix structure of the reference guide matrix when the matrix structure of the reference guide matrix is ​​an M×N structure. In this case, four adjacent measurement guide points M(i, j), M(i, j+1), M(i+1, j), and M(i+1, j+1) of the measurement guide matrix can define a single measurement guide. The measurement guide can represent an actual measurement area corresponding to the reference guide of the reference guide matrix.

[0073] Additionally, the measurement guide matrix generation unit (130) can interpolate or estimate missing measurement guide points using location information of adjacent measurement guide points or surrounding measurement guide areas when a part of the measured alignment key or reference mark is missing or the measurement reliability is low. For example, if a measurement guide point of a specific row or column is not detected, the measurement guide matrix generation unit (130) can calculate the location of the corresponding measurement guide point using the average displacement of adjacent measurement guide points, linear interpolation values, or deformation trends of surrounding areas.

[0074] Additionally, the measurement guide matrix generation unit (130) can determine the validity of the measurement guide point. For example, if the position of a measured guide point exceeds a preset allowable error range relative to a reference guide point, or if the spacing or angle relationship with adjacent measurement guide points is abnormal, the measurement guide matrix generation unit (130) can determine that the measurement guide point is an abnormal measurement value. In this case, the measurement guide matrix generation unit (130) can exclude the measurement guide point, request a re-measurement, or replace it with a measurement guide point corrected based on surrounding measurement guide points.

[0075] Additionally, the measurement guide matrix generation unit (130) may calculate the position coordinates of the measurement guide points and then perform at least one of matrix index alignment, coordinate system transformation, rotation correction, scale correction, or offset correction to maintain a correspondence with the reference guide matrix. Accordingly, the measurement guide matrix may have a structure that corresponds 1:1 with the reference guide matrix and can be reliably used for determining the divided area and calculating the correction coordinates in subsequent steps. In this way, the measurement guide matrix generation unit (130) can generate a measurement guide matrix that reflects the actual substrate or equipment condition by calculating a plurality of measurement guide points based on the actual measurement positions of the alignment key or reference mark formed on the substrate to be exposed, and arranging them to correspond to the matrix structure of the reference guide matrix. Accordingly, actual positional deformation caused by the bending of the substrate, mounting error, thermal deformation, stage error, or optical distortion can be reflected in the correction for each divided area.

[0076] Additionally, the correction coordinate calculation unit (150) calculates the horizontal ratio and the vertical ratio that the correction target coordinate has in the first direction and the second direction within the division guide area, and calculates the correction coordinate by applying the horizontal ratio and the vertical ratio to the corresponding measurement guide of the measurement guide matrix. In an embodiment, the correction coordinate calculation unit (150) can calculate the horizontal ratio and the vertical ratio that the correction target coordinate has in the first direction and the second direction within the division guide area, and calculate the correction coordinate corresponding to the correction target coordinate by applying the horizontal ratio and the vertical ratio to the corresponding measurement guide of the measurement guide matrix.

[0077] Here, the coordinates to be corrected may be coordinates requiring positional correction among the coordinates constituting the exposure target pattern. For example, the coordinates to be corrected may be vertex coordinates of polygon vector data, end coordinates of a line segment, pattern outline coordinates, intermediate coordinates before bitmap conversion, or reference coordinates used for generating frame data for a digital micromirror device.

[0078] When the division guide area where the correction target coordinate is located is determined by the division area determination unit (140), the correction coordinate calculation unit (150) can calculate the relative position that the correction target coordinate occupies within the corresponding division guide area. At this time, the division guide area may be a single reference guide area included in the reference guide matrix and may be defined by four adjacent reference guide points.

[0079] For example, the division guide area may be defined by a first reference guide point A, a second reference guide point B, a third reference guide point C, and a fourth reference guide point D. In this case, the direction connecting the first reference guide point A and the second reference guide point B may be defined as a first direction, i.e., a horizontal direction, and the direction connecting the first reference guide point A and the third reference guide point C may be defined as a second direction, i.e., a vertical direction.

[0080] The correction coordinate calculation unit (150) can calculate the relative position that the correction target coordinate P has in the first direction within the division guide area as a horizontal ratio. For example, the correction coordinate calculation unit (150) can calculate the ratio of the first direction position of the correction target coordinate P to the first direction width of the division guide area as a horizontal ratio. Additionally, the correction coordinate calculation unit (150) can calculate the relative position that the correction target coordinate P has in the second direction within the division guide area as a vertical ratio. For example, the correction coordinate calculation unit (150) can calculate the ratio of the second direction position of the correction target coordinate P to the second direction height of the division guide area as a vertical ratio.

[0081] For example, if the coordinate P to be corrected is spaced x in the first direction within the reference guide area and the width of the first direction of the reference guide area is Wr, the correction coordinate calculation unit (150) can calculate the horizontal ratio u as x / Wr. Additionally, if the coordinate P to be corrected is spaced y in the second direction within the reference guide area and the height of the second direction of the reference guide area is Hr, the correction coordinate calculation unit (150) can calculate the vertical ratio v as y / Hr. In this case, if the coordinate P to be corrected is located inside the divided guide area, the horizontal ratio u and the vertical ratio v may each have a value of 0 or greater and 1 or less.

[0082] However, the method of calculating the aspect ratio and the aspect ratio is not limited to the above examples. When the division guide area is defined as a quadrilateral, parallelogram, or irregular rectangular area rather than a rectangle, the correction coordinate calculation unit (150) may calculate the aspect ratio and the aspect ratio using the projection position, linear interpolation position, or relative coordinates on the plane coordinate system with respect to the reference side or interpolation reference line of the division guide area. Additionally, when the correction target coordinate is located at the boundary of the division guide area or the outer correction area, the aspect ratio and the aspect ratio may have a value less than 0 or greater than 1.

[0083] The correction coordinate calculation unit (150) can apply the calculated horizontal and vertical ratios to the corresponding measurement guides of the measurement guide matrix. Here, the corresponding measurement guide may be a measurement guide area having the same matrix index as the reference guide area where the correction target coordinate is located. For example, if the correction target coordinate P is located in the (i, j) division guide area of ​​the reference guide matrix, the correction coordinate calculation unit (150) can select the (i, j) measurement guide of the measurement guide matrix as the corresponding measurement guide.

[0084] The corresponding measurement guide can be defined by four measurement guide points corresponding to each of the four reference guide points in the reference guide area. That is, measurement guide points A′, B′, C′, and D′ can be defined corresponding to reference guide points A, B, C, and D, and the correction coordinate calculation unit (150) can apply the horizontal ratio and vertical ratio calculated in the reference guide area to the measurement guide area enclosed by measurement guide points A′, B′, C′, and D′.

[0085] In one embodiment, the correction coordinate calculation unit (150) can calculate correction coordinates by determining a first direction position of a corresponding measurement guide using a horizontal ratio and determining a second direction position of a corresponding measurement guide using a vertical ratio. For example, the correction coordinate calculation unit (150) can calculate a correction coordinate P′ by calculating a corresponding point on the upper side and the lower side of the measurement guide area according to the horizontal ratio u, and by interpolating the position between the corresponding points according to the vertical ratio v.

[0086] Specifically, when the measurement guide area is defined by four measurement guide points A′, B′, C′, and D′, the correction coordinate calculation unit (150) can calculate a first interpolation point E′ corresponding to the horizontal ratio u on the upper measurement side A′B′ and a second interpolation point F′ corresponding to the horizontal ratio u on the lower measurement side C′D′. Subsequently, the correction coordinate calculation unit (150) can calculate a position corresponding to the vertical ratio v on the interpolation line connecting the first interpolation point E′ and the second interpolation point F′ as the correction coordinate P′.

[0087] For example, the correction coordinate calculation unit (150) can calculate the correction coordinates according to the following relationship.

[0088] E′ = A′ + u × (B′ - A′)

[0089] F′ = C′ + u × (D′ - C′)

[0090] P′ = E′ + v × (F′ - E′)

[0091] Here, u is the aspect ratio, v is the aspect ratio, and P′ can be the correction coordinate corresponding to the correction target coordinate P.

[0092] The correction coordinate P′ calculated in this way may be a coordinate converted to a measurement guide area that reflects the actual measured substrate or equipment condition, while maintaining the relative position that the correction target coordinate P has within the reference guide area. Accordingly, the correction coordinate calculation unit (150) can convert the coordinates based on design data into coordinates corresponding to the actual measurement result, and can correct position distortions caused by substrate deformation, stage error, optical distortion, or alignment error on a region-by-region basis.

[0093] Additionally, the correction coordinate calculation unit (150) may repeatedly perform the correction coordinate calculation process for a plurality of correction target coordinates constituting the exposure target pattern. Accordingly, each coordinate of the exposure target pattern may be corrected based on the division guide area to which it belongs and the measurement guide corresponding to that area.

[0094] In this way, the correction coordinate calculation unit (150) calculates the correction coordinates using the horizontal and vertical ratios of the correction target coordinates, thereby precisely reflecting position distortions that change continuously within the divided guide area, unlike simple movement amount-based correction or block-unit movement correction. Accordingly, correction discontinuities between adjacent divided areas can be mitigated, and the alignment precision and overlay quality of the exposure pattern required on a large-area substrate can be improved.

[0095] Additionally, the correction coordinate calculation unit (150) calculates the two ends of the first interpolation line between the first measurement side and the second measurement side of the corresponding measurement guide based on the horizontal ratio, calculates the two ends of the second interpolation line between the third measurement side and the fourth measurement side of the corresponding measurement guide based on the vertical ratio, and calculates the intersection point of the first interpolation line and the second interpolation line as the correction coordinate. In one embodiment, the correction coordinate calculation unit (150) calculates the two ends of the first interpolation line between the first measurement side and the second measurement side of the corresponding measurement guide based on the horizontal ratio, calculates the two ends of the second interpolation line between the third measurement side and the fourth measurement side of the corresponding measurement guide based on the vertical ratio, and calculates the intersection point of the first interpolation line and the second interpolation line as the correction coordinate.

[0096] Here, the corresponding measurement guide may be a measurement guide corresponding to the reference guide where the coordinate to be corrected is located. For example, if the reference guide is defined by four reference guide points A, B, C, and D, and the coordinate to be corrected P is located within the reference guide, the measurement guide having the same matrix index as the reference guide in the measurement guide matrix may be defined by four measurement guide points A′, B′, C′, and D′.

[0097] In this case, the first measurement side may be a side connecting the first measurement guide point A′ and the second measurement guide point B′, and the second measurement side may be a side connecting the third measurement guide point C′ and the fourth measurement guide point D′. Additionally, the third measurement side may be a side connecting the first measurement guide point A′ and the third measurement guide point C′, and the fourth measurement side may be a side connecting the second measurement guide point B′ and the fourth measurement guide point D′. However, the names and connection relationships of each measurement side may vary depending on the arrangement direction of the measurement guide points, and the technical concept of the present invention is not limited thereto.

[0098] The correction coordinate calculation unit (150) can first calculate a horizontal ratio, which is the relative position of the correction target coordinate P in the first direction within the reference guide. The horizontal ratio may be the ratio of the first direction position of the correction target coordinate P to the first direction width of the reference guide. The correction coordinate calculation unit (150) can calculate the two ends of the first interpolation line by applying the calculated horizontal ratio to the first measurement side and the second measurement side of the corresponding measurement guide, respectively.

[0099] For example, when the horizontal ratio is denoted as u, the correction coordinate calculation unit (150) can calculate a first interpolation point E′ corresponding to the horizontal ratio u on the first measured side A′B′ and a second interpolation point F′ corresponding to the horizontal ratio u on the second measured side C′D′. In this case, the first interpolation point E′ and the second interpolation point F′ can be calculated as follows.

[0100] E′ = A′ + u × (B′ - A′)

[0101] F′ = C′ + u × (D′ - C′)

[0102] The correction coordinate calculation unit (150) can define a first interpolation line by connecting the first interpolation point E′ and the second interpolation point F′. The first interpolation line may represent a set of positions within a corresponding measurement guide where the horizontal ratio u is maintained constant. That is, the first interpolation line may be a reference line that reflects the horizontal relative position of the correction target coordinate P within the reference guide onto the measurement guide.

[0103] Additionally, the correction coordinate calculation unit (150) can calculate a vertical ratio, which is the relative position of the correction target coordinate P in the second direction within the reference guide. The vertical ratio may be the ratio of the second direction position of the correction target coordinate P to the second direction height of the reference guide. The correction coordinate calculation unit (150) can calculate the two endpoints of the second interpolation line by applying the calculated vertical ratio to the third measurement side and the fourth measurement side of the corresponding measurement guide, respectively.

[0104] For example, when the vertical ratio is denoted as v, the correction coordinate calculation unit (150) can calculate a third interpolation point G′ corresponding to the vertical ratio v on the third measurement side A′C′ and a fourth interpolation point H′ corresponding to the vertical ratio v on the fourth measurement side B′D′. In this case, the third interpolation point G′ and the fourth interpolation point H′ can be calculated as follows.

[0105] G′ = A′ + v × (C′ - A′)

[0106] H′ = B′ + v × (D′ - B′)

[0107] The correction coordinate calculation unit (150) can define a second interpolation line by connecting the third interpolation point G′ and the fourth interpolation point H′. The second interpolation line may represent a set of positions within the corresponding measurement guide where the vertical ratio v is maintained constant. That is, the second interpolation line may be a reference line that reflects the vertical relative position of the correction target coordinate P within the reference guide on the measurement guide.

[0108] Subsequently, the correction coordinate calculation unit (150) calculates the intersection point of the first interpolation line and the second interpolation line, and can determine the intersection point as the correction coordinate P′ corresponding to the correction target coordinate P. That is, the correction coordinate P′ may be a position within the measurement guide that simultaneously satisfies the horizontal ratio u and the vertical ratio v.

[0109] According to this method, the correction coordinate calculation unit (150) can calculate the final correction coordinate by independently reflecting the horizontal relative position and the vertical relative position of the correction target coordinate P to the measurement guide, respectively, and then using the intersection point of the two interpolation lines. Accordingly, even if the measurement guide is deformed into a trapezoid, parallelogram, or irregular quadrilateral rather than a rectangle, it is possible to calculate the correction coordinate corresponding to the actual measurement shape while maintaining the relative positional relationship of the correction target coordinate P.

[0110] Additionally, the correction coordinate calculation unit (150) may use a straight line equation, a vector equation, or a line segment intersection operation to calculate the intersection point of the first interpolation line and the second interpolation line. For example, the first interpolation line may be defined as a straight line passing through the first interpolation point E′ and the second interpolation point F′, and the second interpolation line may be defined as a straight line passing through the third interpolation point G′ and the fourth interpolation point H′. The correction coordinate calculation unit (150) may calculate the correction coordinate P′ by performing an intersection operation of the two straight lines.

[0111] In one embodiment, if it is determined that the first interpolation line and the second interpolation line do not intersect exactly due to numerical error or measurement error, the correction coordinate calculation unit (150) can calculate the shortest distance point between the two interpolation lines, the approximate intersection point based on least squares, or the midpoint of the closest points of the two interpolation lines as the correction coordinate. Accordingly, the correction coordinate can be calculated stably even when measurement noise is included.

[0112] Additionally, the correction coordinate calculation unit (150) may repeat the intersection calculation process for a plurality of correction target coordinates constituting the exposure target pattern. Each correction target coordinate may be converted into an intersection point within a corresponding measurement guide according to the horizontal and vertical ratios of the divided guide area in which it is located, and as a result, the entire coordinate of the exposure target pattern may be corrected by area based on the measurement guide matrix.

[0113] In this way, the correction coordinate calculation unit (150) calculates the intersection point of the first interpolation line corresponding to the horizontal ratio and the second interpolation line corresponding to the vertical ratio as the correction coordinate, thereby allowing the relative position of the correction target coordinate to be maintained more precisely while reflecting the deformation state measured in the actual substrate or equipment. Accordingly, local positional distortions caused by substrate deformation, stage error, optical distortion, and alignment error can be precisely corrected in the segmented guide area unit, and boundary discontinuities or pattern step differences that may occur in the block unit movement method can be mitigated.

[0114] Additionally, the guide matrix-based exposure pattern multi-segment alignment correction device further includes a correction pattern generation unit that generates at least one of corrected polygon vector data, exposure bitmap data, or frame data for a digital micromirror device based on the correction coordinates, and the correction pattern generation unit generates exposure pattern data in which local distortion of the exposure pattern is corrected according to at least one of substrate deformation, stage error, optical distortion, and alignment error using the correction coordinates calculated for each of the segmented guide areas. In one embodiment, the guide matrix-based exposure pattern multi-segment alignment correction device (100) may further include a correction pattern generation unit (160) that generates corrected exposure pattern data based on the correction coordinates calculated by the correction coordinate calculation unit (150).

[0115] The correction pattern generation unit (160) receives correction coordinates corresponding to the correction target coordinates from the correction coordinate calculation unit (150) and can reflect the correction coordinates in the exposure target pattern data. Here, the exposure target pattern data may include at least one of polygon vector data generated from design data, intermediate pattern data before raster conversion, bitmap data for exposure, or frame data for a digital micromirror device (DMD).

[0116] In one embodiment, the correction pattern generation unit (160) can generate corrected polygon vector data based on correction coordinates. For example, if the exposure target pattern includes a plurality of polygons, line segments, closed curves, or rectangular elements, the correction pattern generation unit (160) can replace the vertex coordinates or control coordinates constituting the polygon vector data with correction coordinates, or reconstruct the position, shape, or boundary of the polygon based on the correction coordinates. Accordingly, the polygon vector data based on design data can be converted into corrected polygon vector data that reflects the actual substrate or equipment condition.

[0117] In another embodiment, the correction pattern generation unit (160) can generate bitmap data for exposure based on correction coordinates. For example, the correction pattern generation unit (160) can generate bitmap data for exposure by rasterizing the corrected polygon vector data. In this case, since the correction coordinates can be reflected in the polygon vector coordinates before the bitmap data is generated, boundary discontinuities or pattern step differences can be reduced compared to a method of moving the image in blocks after the bitmap is generated.

[0118] In another embodiment, the correction pattern generation unit (160) can generate frame data for a digital micromirror device based on correction coordinates. For example, the correction pattern generation unit (160) can generate DMD frame data based on corrected exposure bitmap data or structured virtual frame data by reflecting at least one of the pixel pitch, tilt angle, subpixel mapping structure, and scan position of the DMD. The DMD frame data can be output to the DMD at the time of exposure and used to form a corrected exposure pattern on the substrate to be exposed.

[0119] The correction pattern generation unit (160) can generate exposure pattern data in which local distortion of the exposure pattern is corrected using correction coordinates calculated for each divided guide area. Specifically, the correction pattern generation unit (160) can reflect the correction coordinates corresponding to the divided guide area in the pattern data based on the divided guide area to which each coordinate constituting the exposure target pattern belongs. Accordingly, instead of applying the same correction value to the entire area of ​​the exposure target pattern, different correction results can be reflected for each divided guide area.

[0120] For example, even if some areas of the substrate are deformed in a first direction due to thermal deformation or warping, and other areas are deformed in a second direction due to stage error or optical distortion, the correction pattern generation unit (160) can reflect the deformation pattern of each area in the exposure pattern data using correction coordinates calculated for each divided guide area. Accordingly, the correction pattern generation unit (160) can generate exposure pattern data in which local distortion of the exposure pattern due to at least one of substrate deformation, stage error, optical distortion, and alignment error is corrected.

[0121] Additionally, the correction pattern generation unit (160) can generate exposure pattern data to maintain correction continuity between adjacent division guide regions. For example, if a single pattern element is located across multiple division guide regions, the correction pattern generation unit (160) can divide the pattern element according to the boundaries of the division guide regions and apply correction coordinates corresponding to each divided pattern element. Alternatively, the correction pattern generation unit (160) can correct the boundary of the pattern element so that it is continuously connected by using an interpolation value between the correction coordinates calculated in adjacent division guide regions.

[0122] Additionally, the correction pattern generation unit (160) can generate final exposure pattern data by reflecting the correction coordinates and considering at least one of the resolution of the exposure equipment, the DMD pixel pitch, the laser spot size, the scan direction, the stage movement speed, or the exposure timing. For example, the corrected polygon vector data can be converted into bitmap data after reflecting the exposure spot size or line width correction value, and the bitmap data can be converted into virtual frame data or DMD frame data according to the subpixel mapping structure of the DMD.

[0123] In one embodiment, the correction pattern generation unit (160) may first generate polygon vector data with correction coordinates reflected therein, convert the corrected polygon vector data into rectangle data, and then convert the rectangle data into bitmap data for exposure or frame data for DMD. In another embodiment, the correction pattern generation unit (160) may generate DMD frame data that can be output at the time of exposure by reflecting correction coordinates to already generated intermediate pattern data or virtual frame data.

[0124] Additionally, the correction pattern generation unit (160) can transmit the corrected exposure pattern data to the exposure control unit or DMD controller. The exposure control unit or DMD controller can control the mirror drive of the DMD, the light source emission timing, or the stage synchronization signal based on the corrected exposure pattern data. Accordingly, the corrected exposure pattern data generated by the correction pattern generation unit (160) can be reflected on the substrate in the actual exposure process. In this way, the correction pattern generation unit (160) can generate exposure pattern data with local distortion of the exposure pattern corrected by reflecting the correction coordinates calculated for each divided guide area into at least one of polygon vector data, bitmap data for exposure, or frame data for a digital micromirror device. Accordingly, the present invention can directly reflect positional distortion caused by substrate deformation, stage error, optical distortion, and alignment error in the pattern data generation stage, mitigate boundary discontinuities or stitching defects that may occur in conventional block shift methods, and improve pattern alignment and overlay precision required in high-resolution and large-area digital exposure processes.

[0125] FIG. 2 is a timing diagram illustrating the concept of ns-unit delay correction parameters and phase alignment logic according to one embodiment of the present invention.

[0126] Referring to FIG. 2, an exposure equipment control device according to one embodiment of the present invention can control a light source output signal (LD Sig Out) corresponding to a plurality of digital micromirror devices (DMD) or a plurality of exposure heads based on an external trigger input signal (Trig In). The external trigger input signal may be generated based on at least one of a stage movement position, an encoder signal, a line trigger, or a frame trigger, and may be repeatedly input based on one scan cycle or scan pitch.

[0127] As illustrated in FIG. 2, when a Trig In signal is input, the LD pulse module can sequentially set pulse driving intervals corresponding to a plurality of DMD chips or a plurality of exposure heads, such as DMD1, DMD2, DMD3, …, DMD(N-1), and DMDN. Here, the LD pulse module may be configured to generate pulse control information for controlling the emission timing of a light source corresponding to each DMD chip or each exposure head.

[0128] In one embodiment, the LD pulse module can switch the LD Sig Out signal to the ON state after a predetermined delay time has elapsed based on the time when an external trigger input signal is generated. The delay time may be a time interval from the time when the scan starts or the time when the trigger input is generated until the time when the actual light source output is initiated, and may be adjusted, for example, in units of about 50ns or ns. Accordingly, the time difference between the time when the trigger signal is input and the time when the actual exposure light is output can be precisely corrected.

[0129] In addition, the exposure equipment control device can set an on-time delay value or an on-time setting value for each DMD chip or each exposure head, during which the LD Sig Out signal remains in the ON state. The on-time setting value may refer to the time during which the LD Sig Out signal remains in the ON state and may be variably set, for example, in units of 1 ns. Furthermore, the on-time setting value may be set differently depending on process conditions, light intensity correction values, light output deviation per head, DMD output timing, or exposure intensity requirements.

[0130] The LD Sig Out signal may be an output signal for controlling the on / off of the LD. That is, the exposure equipment control device generates an LD Sig Out signal from each DMD control board based on a signal input from the trigger board, and can control the light source's light emission start time and light emission maintenance time using the LD Sig Out signal. Accordingly, the pattern frame output from each DMD chip or each exposure head can be precisely synchronized with the actual light source's light emission time.

[0131] In FIG. 2, Scan Pitch may represent a single scan interval or a reference cycle required for a single scan. The exposure equipment control device may repeatedly receive Trig In signals corresponding to the Scan Pitch and output an LD Sig Out signal by applying the same or corrected delay time and on-time setting values ​​for each scan interval. Accordingly, light output can be achieved at a constant timing at each exposure position even in a high-speed scanning environment where the stage moves continuously.

[0132] In one embodiment, a plurality of DMD chips or a plurality of exposure heads may have different physical arrangements, signal transmission paths, optical path lengths, or electrical response characteristics. Since the actual exposure time of each head may differ due to these differences, the exposure equipment control device may set delay correction parameters for each DMD chip or each exposure head. For example, the LD output signal corresponding to DMD1 and the LD output signal corresponding to DMDN may be based on the same Trig In signal, but may be subject to different Delay time or On time delay.

[0133] In addition, when multiple DMD chips are driven sequentially within a single scan pitch, the exposure equipment control device can adjust the output timing of the LD Sig Out signal by considering the driving order and pulse output interval of each DMD chip. Accordingly, even in an environment where multiple DMD chips or multiple exposure heads operate in parallel or sequentially, the pattern output of each head and the light source emission can be matched with each other. Thus, according to one embodiment of the present invention, since the delay time and on-time setting value of the LD output signal can be adjusted in units of ns based on the trigger input signal, the phase deviation between heads, signal transmission delay, light source response delay, and exposure timing error that may occur in a multi-head exposure system can be precisely corrected.

[0134] Accordingly, the present invention can synchronize the frame output time of each head with the light source emission time in a digital exposure device in which a plurality of exposure heads are driven simultaneously or sequentially, and can reduce pattern step difference, overlap error, and overlay defects in the stitching area. In addition, since stable exposure amount control and precise pattern formation are possible even under high-speed scanning conditions, exposure quality and productivity can be improved in large-area substrate or fine pattern exposure processes.

[0135] FIG. 3 is a diagram showing an example of constructing a multi-head exposure system according to an embodiment of the present invention. Referring to FIG. 3, the multi-head exposure system according to an embodiment of the present invention may include a plurality of exposure heads, and for example, may be implemented as a 6-head (6Head) structure in which 6 exposure heads are arranged in parallel on a single equipment frame or head mounting structure.

[0136] Each exposure head may include at least one of a digital micromirror device (DMD), a projection optical system, a light source module, a head driving unit, and a head control board. A plurality of exposure heads may be arranged at regular intervals along the movement direction of the stage or the width direction of the substrate, and each exposure head may irradiate a pattern corresponding to a different area of ​​the substrate to be exposed.

[0137] In one embodiment, a multi-head exposure system may drive a plurality of exposure heads simultaneously or sequentially to expose a large-area substrate or panel at high speed. In this case, the exposure area handled by each exposure head may partially overlap with the exposure area of ​​an adjacent head or be connected to each other at the boundary. Therefore, the output timing, light intensity, scan position, and pattern frame output timing between the plurality of exposure heads must be aligned with each other.

[0138] The multi-head exposure system illustrated in FIG. 3 can be configured to synchronize the timing of the DMD frame output corresponding to each exposure head with the timing of the light source emission based on this multiple-head configuration. For example, a trigger board or master control unit can generate multiple head-specific trigger signals based on a stage encoder signal, a reference clock, or an external trigger signal, and the control board of each exposure head can control the DMD pattern output and the LD light source output according to the corresponding trigger signal.

[0139] In addition, each exposure head may have different time delays or positional deviations depending on differences in physical mounting position, signal transmission path, optical path length, or light source response characteristics. Accordingly, a multi-head exposure system can set delay correction values, phase alignment values, scan offset values, or light source on-time values ​​for each head, and correct the output timing of each exposure head by reflecting these values.

[0140] In one embodiment, the multi-head exposure system provides the same reference trigger for a plurality of exposure heads, but may apply different delay correction parameters for each head. Accordingly, patterns output from the plurality of exposure heads can be irradiated on the actual substrate according to the same position reference or the same scan reference.

[0141] In addition, the multi-head exposure system can precisely control the pattern output position and the light source emission timing for each head so that no step difference, overlap error, or omission of the pattern occurs at the boundary or stitching area between adjacent exposure heads. For example, at the boundary of the exposure area handled by the first exposure head and the second exposure head, the pattern frame output timing and LD output timing of both heads can be controlled to be aligned with each other.

[0142] The enlarged image on the left of FIG. 3 illustrates the configuration of a single exposure head or head module as an example, wherein the head module may include an optical system, a driving unit, a cable connection unit, and a head support structure. The image on the right of FIG. 3 shows a state in which a plurality of exposure heads are arranged in parallel on a single piece of equipment, demonstrating that each head module may be arranged corresponding to a common stage or a common equipment frame.

[0143] As such, a multi-head exposure system according to one embodiment of the present invention can improve the exposure throughput of a large-area substrate by configuring a plurality of DMD exposure heads in parallel. In addition, by precisely synchronizing the trigger signal, DMD frame output, and LD emission timing of each head, stitching error and overlay error at the boundary between heads can be reduced even under high-speed scanning conditions. Accordingly, the multi-head exposure system of the present invention can be effectively applied to digital exposure processes that require both high productivity and precise pattern alignment simultaneously, such as panel interposers, large-area packaging substrates, high-multilayer PCBs, display substrates, and fine RDL formation processes.

[0144] FIG. 4 is a diagram showing an exposure pattern image in which a stitching error occurs before timing correction or phase alignment correction is applied in a multi-head exposure system. Referring to FIG. 4, when multiple exposure heads are responsible for adjacent exposure areas to form a pattern, if the output timing, scan position, light source emission time, or phase alignment value between each exposure head does not match exactly, a stitching error may occur at the head boundary or in the overlapping exposure area.

[0145] The top images of FIG. 4 exemplarily illustrate a state in which stitching errors occur in a plurality of line patterns extending in the horizontal direction. The line patterns may be partially bent or form steps at the boundary of an adjacent exposure head or an adjacent scan section. That is, the pattern, which should be formed as a single continuous line, may be misaligned in the vertical direction at the boundary, or the width or position of the line may change partially, thereby reducing the pattern continuity.

[0146] The bottom images of FIG. 4 exemplarily illustrate a state in which stitching errors occur in a line pattern extending in an inclined direction. In the inclined line pattern, the inclination, spacing, or connection position of the pattern at the boundary may be inconsistent due to positional deviation between heads or trigger timing deviation. Such stitching errors can cause open circuits, step differences, uneven line widths, or overlay defects in the fine wiring pattern.

[0147] Such stitching errors can occur when multiple exposure heads fail to output the same pattern frame from the same reference position. For example, the actual exposure timing may differ due to signal transmission delays of each exposure head, DMD frame output delays, LD light source response delays, processing delays of stage encoder signals, or differences in optical paths between heads. As a result, patterns that should be continuously connected in the design data may be formed misaligned on the actual substrate.

[0148] In addition, stitching errors can occur not only at the boundaries where the exposure areas of each head are connected to each other, but also between the repetitive scan sections of the same head. For example, if the timing of the generation of the trigger signal corresponding to the scan pitch and the timing of the on / off of the actual LD ​​output signal are not aligned, positional deviations of the pattern may accumulate between the repetitive scan sections.

[0149] An exposure equipment control device according to one embodiment of the present invention can set delay correction parameters and phase alignment values ​​for each exposure head or each DMD control board based on a trigger input signal to reduce the stitching error before correction as shown in FIG. 4. In addition, the exposure equipment control device can precisely synchronize the DMD frame output time and the light source emission time by adjusting the delay time and on-time of the LD output signal for each head in units of ns. Therefore, FIG. 4 can be understood as an example to explain the technical background requiring trigger-based synchronization control and head-specific delay correction in a multi-head exposure system. That is, the stitching error image before correction shown in FIG. 4 indicates that timing deviations and position deviations between multiple exposure heads can affect the continuity of the exposure pattern, and such pattern misalignment can be mitigated or prevented through the delay correction and phase alignment control of the present invention.

[0150] FIG. 5 is a diagram showing an exposure pattern image after DB-based timing correction according to one embodiment of the present invention.

[0151] Referring to FIG. 5, in a multi-head exposure system comprising a plurality of exposure heads, after head-specific timing correction values ​​or phase alignment values ​​are applied, it can be seen that the stitching error between adjacent exposure areas is mitigated. That is, FIG. 5 exemplarily shows a pattern image after correction that contrasts with the stitching error image before correction shown in FIG. 4.

[0152] The top images of FIG. 5 show the results of applying timing correction to multiple line patterns extending in the horizontal direction. Before correction, the line patterns may bend or become misaligned in the vertical direction at the boundaries of adjacent exposure heads or adjacent scan sections; however, as shown in FIG. 5, after correction, multiple line patterns can be connected relatively continuously based on the boundaries. Accordingly, pattern step differences, line breaks, or positional misalignment at the boundaries between heads can be reduced.

[0153] The bottom images of Fig. 5 show the results of applying DB-based timing correction to line patterns extending in an inclined direction. Although inclined line patterns can be sensitive to time deviations between heads or scan position deviations, after correction, the inclination and position of the line passing through the boundary can be formed in a more aligned state. Accordingly, the pattern continuity and alignment precision of the stitching area can be improved even in inclined patterns.

[0154] In one embodiment, DB-based timing correction can be performed by storing a pre-measured delay correction value, phase alignment value, scan offset value, or light source on-time value for each of a plurality of exposure heads in a database, and applying the correction parameters stored in the database during the actual exposure process. For example, the exposure equipment control device can read a correction value from the database corresponding to at least one of the DMD frame output delay, LD light source response delay, signal transmission delay, and optical path difference for each head.

[0155] In addition, the exposure equipment control device controls the LD output signal of each DMD control board to turn on / off based on a trigger input signal, and can adjust the light emission start time and light emission maintenance time of the LD output signal by applying head-specific delay correction parameters stored in a database. Accordingly, multiple exposure heads can be controlled to irradiate a pattern corresponding to the same reference position or the same scan pitch.

[0156] The corrected image shown in Fig. 5 indicates that the pattern position deviation at the boundary between adjacent exposure heads can be reduced and the continuity of the exposure pattern improved by this DB-based timing correction. In particular, in a multi-head exposure system with 6 or more heads arranged in parallel, since the physical characteristics and signal delay characteristics of each head may differ, it is advantageous to database and apply correction parameters for each head.

[0157] In one embodiment, the database may be updated through an equipment initial calibration process, a periodic inspection process, or a test exposure result analysis process. For example, the positional deviation of the stitching area in the test exposure pattern may be measured, and based on the measured positional deviation, a trigger delay value, an LD on-time value, or a phase correction value for each head may be calculated and stored in a correction parameter database. Subsequently, during actual mass production exposure, the stored correction parameters may be recalled and applied to the output timing control of each head. Thus, according to the DB-based timing correction in one embodiment of the present invention, the DMD frame output and LD emission timing can be aligned by reflecting the unique delay characteristics and phase deviation of each exposure head. Accordingly, as shown in FIG. 5, stitching errors can be mitigated in both horizontal and inclined lines in the exposure pattern after correction, and pattern alignment and overlay precision at the head boundary can be improved.

[0158] Accordingly, the present invention can reduce defects at the boundary between heads in a multi-head digital exposure device, enable stable pattern formation even under high-speed scanning conditions, and simultaneously improve the exposure quality and productivity required in large-area panels, packaging substrates, and fine wiring processes.

[0159] Meanwhile, the methods according to the various embodiments of the present invention described above can be implemented in the form of an application or software program that can be installed on an existing electronic device.

[0160] In addition, the whole or part of the method may be composed of multiple software function modules and implemented on an operating system (OS). Alternatively, each step may be composed of a single software function module, or each step may be combined to form a single software function module and implemented on an operating system. Therefore, even if all of the embodiments of the present disclosure are not implemented as a single software function module, if multiple software function modules implement each step of the present disclosure and multiple software function modules are implemented on a single operating system, it can be understood that the method of the present disclosure has been implemented.

[0161] In addition, the methods according to the various embodiments of the present invention described above can be implemented solely through software upgrades or hardware upgrades of existing electronic devices. Furthermore, the various embodiments of the present invention described above can also be performed through an embedded server equipped in an electronic device or an external server of the electronic device.

[0162] Meanwhile, according to one embodiment of the present invention, the various embodiments described above may be implemented as software comprising instructions stored on a computer-readable recording medium using software, hardware, or a combination thereof. In some cases, the embodiments described herein may be implemented as the processor itself. According to the software implementation, embodiments such as the procedures and functions described herein may be implemented as separate software modules. Each of the software modules may perform one or more functions and operations described herein.

[0163] Meanwhile, a computer or a similar device may include a device according to the disclosed embodiments, which is capable of calling instructions stored from a storage medium and operating according to the called instructions. When said instructions are executed by a processor, the processor may perform a function corresponding to said instructions directly or by using other components under the control of said processor. The instructions may include code generated or executed by a compiler or an interpreter.

[0164] A computer-readable recording medium may be provided in the form of a non-transitory computer-readable recording medium. Here, "non-transitory" simply means that the storage medium does not contain a signal and is tangible, without distinguishing whether data is stored semi-permanently or temporarily on the storage medium. In this context, a non-transitory computer-readable medium refers to a medium that stores data semi-permanently and is readable by a device, rather than a medium that stores data for a short moment, such as registers, caches, or memory. Specific examples of non-transitory computer-readable media may include CDs, DVDs, hard disks, Blu-ray discs, USBs, memory cards, and ROMs.

[0165] As described above, exemplary embodiments have been disclosed in the drawings and specification. Although specific terms have been used to describe the embodiments in this specification, they are used only for the purpose of explaining the technical concept of this disclosure and are not intended to limit the meaning or the scope of this disclosure as defined in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true technical scope of protection of this disclosure should be determined by the technical concept of the appended claims.

Claims

Claim 1 A guide matrix-based exposure pattern multi-segment alignment correction device comprises: a reference guide point extraction unit that extracts a plurality of reference guide points from design data corresponding to an exposure target pattern or pattern data generated from said design data; a reference guide matrix generation unit that generates a reference guide matrix including a plurality of reference guides by arranging the plurality of reference guide points in a matrix form; a measurement guide matrix generation unit that generates a measurement guide matrix including a plurality of measurement guides based on a plurality of measurement guide points measured on an exposure target substrate or an exposure equipment; and a segmentation area determination unit that determines a segmentation guide area where the correction target coordinates of the exposure target pattern are located by aligning the reference guide matrix and the measurement guide matrix with each other. A guide matrix-based exposure pattern multi-segment alignment correction device comprising: a correction coordinate calculation unit that calculates a correction coordinate corresponding to the correction target coordinate by applying the relative position of the correction target coordinate within the segmented guide area to the measurement guide matrix; wherein the correction coordinate calculation unit calculates the correction coordinate in the segmented guide area unit to correct the positional distortion of the exposure target pattern by area; wherein the correction coordinate calculation unit calculates the horizontal ratio and the vertical ratio that the correction target coordinate has in the first direction and the second direction within the segmented guide area, and calculates the correction coordinate by applying the horizontal ratio and the vertical ratio to the corresponding measurement guide of the measurement guide matrix; wherein the correction coordinate calculation unit calculates the two ends of a first interpolation line between the first measurement side and the second measurement side of the corresponding measurement guide based on the horizontal ratio, calculates the two ends of a second interpolation line between the third measurement side and the fourth measurement side of the corresponding measurement guide based on the vertical ratio, and calculates the intersection point of the first interpolation line and the second interpolation line as the correction coordinate. Claim 2 A guide matrix-based exposure pattern multi-segment alignment correction device according to claim 1, wherein the reference guide point extraction unit extracts at least one of an alignment key, a reference mark, a pattern outer point, a pattern inner point, and a user-specified reference point included in the design data as the plurality of reference guide points. Claim 3 A guide matrix-based exposure pattern multi-segment alignment correction device according to claim 1, wherein the reference guide matrix generating unit defines one reference guide using at least four reference guide points adjacent to each other among the plurality of reference guide points, and generates the reference guide matrix by arranging the plurality of reference guides in row and column directions. Claim 4 A guide matrix-based exposure pattern multi-segment alignment correction device according to claim 1, wherein the measurement guide matrix generating unit calculates the plurality of measurement guide points based on the actual measurement position of an alignment key or reference mark formed on the exposure target substrate, and generates the measurement guide matrix by arranging the plurality of measurement guide points to correspond to the matrix structure of the reference guide matrix. Claim 5 delete Claim 6 delete Claim 7 The guide matrix-based exposure pattern multi-segment alignment correction device according to claim 1, wherein the device further comprises a correction pattern generating unit that generates at least one of polygon vector data corrected based on the correction coordinates, bitmap data for exposure, or frame data for a digital micromirror device, and wherein the correction pattern generating unit generates exposure pattern data in which local distortion of the exposure pattern is corrected according to at least one of substrate deformation, stage error, optical distortion, and alignment error using correction coordinates calculated for each segmented guide area.

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