Hole detection system and method

Abstract

The present invention relates to a hole detection system and method, and more particularly, to a system and method for detecting the shape and position of a through hole formed in a substrate. According to one embodiment, a hole detection system for a substrate having a hole may comprise: a substrate supporting device for supporting the substrate; a camera disposed on an upper portion or a lower portion of the substrate to acquire an image of the substrate; the coaxial light source and the camera are arranged on the same side by taking the substrate as the reference; a wide-area light source disposed on the other side of the camera and configured to irradiate a wider area than the coaxial light source; and a detection module which detects the hole based on the image of the substrate obtained by the camera.

Description

Technical Field

[0001] The present invention relates to a hole detection system and method, and more particularly, to a system and method for detecting the shape and position of a through hole formed in a substrate. Background Art

[0002] To achieve higher device integration, the development of next-generation Processing In Memory (PIM) semiconductors is underway. Large-area glass substrates are being used for this purpose. This requires systems and methods for inspecting through-holes formed in these substrates.

[0003] In this regard, Japanese registered patent No. 3859446, “Semiconductor Substrate Inspection Apparatus and Semiconductor Substrate Inspection Method,” discloses a technology for inspecting through-holes by sequentially applying a plurality of DC voltages of varying voltage values ​​to a semiconductor substrate.

[0004] This conventional technology is a technique that can be applied after a conductor is processed into a through-hole, but has a limitation in that it is insufficient to detect the through-hole itself, such as the shape and position of the through-hole.

[0005] On the other hand, the aforementioned background technology is technical information that the inventor possesses in order to derive the present invention or has mastered in the process of deriving the present invention, and is not necessarily the public known technology disclosed to the general public before applying for the present invention. Summary of the Invention

[0006] Technical problems to be solved

[0007] A problem to be solved by the present invention is to shorten the detection time and improve the accuracy during the detection of holes formed in a substrate.

[0008] A problem to be solved by the present invention is to accurately and quickly perform detection of at least one of an inner diameter, an outer diameter, and a position of a hole formed in a substrate.

[0009] A problem to be solved by the present invention is to construct a low-cost and high-efficiency system in the process of detecting holes formed in a substrate.

[0010] Problems of the present invention are not limited to the problems mentioned above, and those skilled in the art can clearly understand other problems not mentioned from the following description.

[0011] Technical Solution

[0012] According to one embodiment of the present invention for solving the problem described above, a hole detection system for a substrate having a hole may include: a substrate supporting device for supporting the substrate; a camera, arranged at the upper or lower part of the substrate, to obtain an image of the substrate; a coaxial light source, based on the substrate, arranged on the same side as the camera; a wide-area light source, arranged on the other side of the camera, and illuminating a wider area than the coaxial light source; and a detection module, for detecting the hole based on the image of the substrate obtained by the camera.

[0013] The hole detection system of one embodiment may further include a camera moving module, which supports the camera at a specified distance from the substrate and causes the camera to reciprocate in a first direction parallel to the substrate. The substrate supporting device may further include a substrate moving module, which causes the substrate to move in a second direction parallel to the substrate and perpendicular to the first direction.

[0014] In the hole detection system of one embodiment, the substrate moving module may include a plurality of linear driving modules, and the plurality of linear driving modules are respectively arranged on both sides of the substrate to enable the substrate to move linearly.

[0015] In the hole detection system of one embodiment, the wide-area light source may include a line light source, and the line light source is arranged to extend side by side with the first direction in which the camera performs the reciprocating motion.

[0016] In the hole detection system of an embodiment, the line light source may illuminate an area of ​​(length corresponding to the width of the substrate)*(width corresponding to the FOV of the camera).

[0017] In the hole detection system of an embodiment, the wide-area light source may include a surface light source, and the surface light source illuminates a region corresponding to the total area of ​​the substrate.

[0018] In the hole detection system of one embodiment, the detection module may include an image processing unit, which processes the image of the substrate based on a global mark and an alignment mark, wherein the global mark corresponds to a location on the substrate, and the alignment mark corresponds to each corner of a group formed by the holes.

[0019] In the hole detection system of one embodiment, the image processing unit may detect at least one of the position of the one group and the position of the holes included in the one group based on the global mark and the alignment mark.

[0020] In the hole detection system of one embodiment, a plurality of points or circles can be radially arranged to form the global mark and the alignment mark. The image processing unit can determine whether the image of the substrate is distorted based on the global mark and the alignment mark, and correct the image of the substrate.

[0021] In a hole detection system of one embodiment, the camera can obtain multiple images of the substrate divided into specified areas, and the image processing unit can merge the multiple divided images based on the global mark and the alignment mark to obtain an image of the entire substrate.

[0022] In the hole detection system of one embodiment, the image processing unit may perform affine transformation on the plurality of segmented images based on the global mark and the alignment mark, and merge the images to be consistent with CAD, thereby obtaining an image of the entire substrate.

[0023] In a hole detection system of one embodiment, the camera may obtain an image of the substrate including both the inner diameter and the outer diameter of the hole, and the detection module may determine whether the hole is of high quality based on the image of the substrate.

[0024] In the hole detection system of one embodiment, the grayscale levels of the inner and outer sides of the boundary line region of the inner diameter in the image of the substrate may differ by more than 10.

[0025] The hole detection method performed by the hole detection system of one embodiment of the present invention for solving the problem described above may include: using a coaxial light source and a wide-area light source to illuminate the substrate, the coaxial light source being based on the substrate and configured on the same side as the camera, and the wide-area light source being configured on the other side of the camera and illuminating a wider area than the coaxial light source; the step of obtaining an image of the substrate using the camera; and the step of detecting the hole based on the obtained image of the substrate.

[0026] In one embodiment of the hole detection method, the step of performing detection may include: correcting the image of the substrate based on a global mark and an alignment mark, the global mark corresponding to a location on the substrate, and the alignment mark corresponding to each corner of a group formed by the hole; and detecting whether the hole is a high-quality product based on the corrected image of the substrate.

[0027] Technical Effects

[0028] According to one of the solutions to the problems of the present invention, in the process of inspecting holes formed in a substrate, the inspection time can be shortened and the accuracy can be improved.

[0029] According to one of the solutions to the problems of the present invention, in the process of detecting at least one of the inner diameter, the outer diameter, and the position of a hole formed in a substrate, detection can be performed accurately and quickly.

[0030] According to one of the solutions to the problems of the present invention, a low-cost and highly efficient system can be constructed in the process of detecting holes formed in a substrate.

[0031] The effects that can be obtained by the present invention are not limited to the problems mentioned above, and ordinary technicians in the technical field to which the present invention belongs can clearly understand other effects not mentioned from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a cross-sectional view showing an example of a through hole formed in a substrate;

[0033] Figure 2 An example diagram of an image of a substrate according to an embodiment of the present invention;

[0034] Figure 3 A side view of a hole detection system for illustrating an embodiment of the present invention;

[0035] Figure 4 is an exemplary diagram of a substrate having a plurality of holes according to an embodiment of the present invention;

[0036] Figure 5 A top view of a hole detection system for illustrating an embodiment of the present invention;

[0037] Figure 6 and Figure 7 This is an example diagram of a light source for illustrating a hole detection system according to an embodiment of the present invention;

[0038] Figure 8 FIG. 1 is a sequence diagram for illustrating a hole detection method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] Below, refer to the attached Figure 1 The advantages, features, and methods for achieving these advantages and features of the present invention will be further clarified by the following detailed embodiments. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various different ways. These embodiments are provided to complete the disclosure of the present invention and to enable those skilled in the art to fully understand the scope of the present invention. The present invention is defined by the scope of the claims.

[0040] The shapes, sizes, ratios, angles, quantities, etc. disclosed in the drawings for illustrating the embodiments of the present invention are exemplary and, therefore, are not limited to the matters shown in the present invention. In addition, in the process of describing the present invention, if it is judged that the specific description of the relevant known technology may unnecessarily confuse the gist of the present invention, its detailed description will be omitted. When using "including", "having", "forming", etc. mentioned in this specification, other parts can be added as long as "only" is not used. When a structural element is represented in the singular form, the plural form is included as long as there is no special explicit recording matter.

[0041] In the process of interpreting structural elements, even if there is no additional explicit description, it should be interpreted as including the error range.

[0042] Although the terms "first," "second," and so on are used to describe various structural elements, these structural elements are not limited by such terms. These terms are only used to distinguish one structural element from other structural elements. Therefore, within the technical concept of the present invention, the first structural element mentioned below may also be the second structural element.

[0043] Unless otherwise specified, like reference numerals refer to like structural elements throughout the specification.

[0044] The various features in the multiple embodiments of the present invention can be combined or combined with each other in a partial or whole manner, and various linkages and drives can be technically realized as is fully understood by ordinary technicians. The various embodiments can be implemented independently of each other or together as a related relationship.

[0045] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

[0046] first, Figure 1 2 is a cross-sectional view showing an example of a through hole 20 formed in the substrate 10. Figure 1 According to an embodiment, the cross-section of the hole 20 may include an upper diameter 21a and a lower diameter 21b, and may include a waist diameter 22a. Furthermore, each hole 20 may be spaced apart by a predetermined distance. In this case, the distance 23 between the through holes 20 may be defined as the distance between the centers of the holes 20.

[0047] according to Figure 1 The cross section of the hole 20 formed in the substrate 10 may be an hourglass shape with wide ends and a narrow center, but may be embodied in various forms according to embodiments such as a cone or a cylinder.

[0048] and, Figure 2 1 is an example diagram of an image of a substrate 10 according to an embodiment of the present invention. Figure 2, as an image of the substrate 10 observed from above or below the substrate 10, including an image of the hole 20. Figure 2 Although the hole 20 is embodied in a circular shape, it can also be embodied in various shapes according to embodiments such as an ellipse, a quadrilateral, etc.

[0049] When referring to Figure 1 and Figure 2 The upper diameter 21a and lower diameter 21b of hole 20 correspond to the upper and lower outer diameters 21 of hole 20. Furthermore, the waist diameter 22a of hole 20 corresponds to the inner diameter 22 of hole 20. In this case, substrate 10 can be divided, based on hole 20, into an area outside outer diameter 21, a tapered area between outer diameter 21 and inner diameter 22, and a pupil area inside inner diameter 22. In this case, due to the influence of the morphological characteristics of each area, the reflectivity of the illuminated light varies. Therefore, a system for detecting by identifying inner diameter 22 and outer diameter 21 of hole 20 is disclosed.

[0050] Relatedly, Figure 3 FIG1 is a side view of a hole detection system 100 for illustrating an embodiment of the present invention. Figure 3 The hole detection system 100 is used to detect holes 20 formed in a substrate 10 . For example, the system can detect a plurality of through holes 20 formed in a large-area glass substrate 10 for a PIM semiconductor.

[0051] According to one embodiment, the hole detection system 100 may include: a substrate support device 110 for supporting a substrate 10; a camera 120, arranged above or below the substrate 10, to obtain an image of the substrate 10; a light source 130, to illuminate the substrate 10; and a detection module 140, to detect the hole 20 based on the image obtained by the camera 120.

[0052] At this time, the substrate support device 110 is a structure that contacts the substrate 10 to support the substrate 10 during the detection of the hole 20. According to an embodiment, the substrate 10 can be supported on both sides of the substrate 10, for example, the edge area of ​​the substrate 10 where no hole 20 is configured can be supported.

[0053] According to an embodiment, the substrate supporting device 110 may include a substrate moving module 111, and the substrate moving module 111 may move the substrate 10 according to the process. Details related to the movement of the substrate 20 will be described later in the relevant part.

[0054] Then, the camera 120 is configured as a structure for obtaining an image of the substrate 10 by being disposed on the upper part or the lower part of the substrate 10. Figure 3 FIG. 2 shows an embodiment in which the camera 120 is disposed on the upper portion of the substrate 10 .

[0055] Relatedly, the camera 120 can be composed of a line scan camera, such as a TDI line scan camera, so that the image of the substrate 10 can be quickly scanned and obtained.

[0056] To this end, the camera 120 can be moved by the camera moving module 150 to obtain an image of the entire area of ​​the substrate 10. To this end, the camera moving module 150 supports the camera 120 at a predetermined distance from the substrate 10 and can move the camera 120 as the process proceeds.

[0057] At this point, the hole detection system 100 needs to obtain an image of the substrate 10 and an image that can identify the hole 20 in order to detect the hole 20. Specifically, in order to identify the inner diameter 22 and outer diameter 21 of the hole 20 for detection, it is necessary to obtain an image of the substrate 10 in which the grayscale level of the inner and outer regions of the boundary between the inner and outer diameters 22 and 21 differ by at least 10. Grayscale refers to the brightness of each pixel in the 256 gradient values ​​from 0 to 255 that are obtained when the substrate image obtained by the camera 120 is digitized.

[0058] That is, the hole detection system 100 can obtain an image of the substrate 10 in which the inner and outer grayscale levels of the boundary line area of ​​the inner diameter 22 differ by more than 10 to detect the inner diameter 22, and can obtain an image of the substrate 10 in which the inner and outer grayscale levels of the boundary line area of ​​the outer diameter 21 differ by more than 10 to detect the outer diameter 21.

[0059] To this end, the hole detection system 100 may include multiple light sources 130. In this case, the light sources 130, serving as structures for illuminating the substrate 10, may be positioned above and below the substrate 10. Specifically, the light sources 130 may include: a coaxial light source 131, positioned on the same side of the substrate 10 as the camera 120; and a wide-area light source 132, positioned on the other side of the camera 120 relative to the substrate 10 and illuminating a wider area than the coaxial light source 131. In this case, the wide-area light source 132 may be positioned perpendicular to the camera 120. The coaxial light source 131 and the wide-area light source 132 can provide light with a strong linearity relative to the substrate 10.

[0060] For example, as shown in FIG3 , when the camera 120 is disposed on the upper portion of the substrate 10, the coaxial light source 131 can be disposed on the upper portion of the substrate 10 to provide coaxial light directed toward the camera 120. Furthermore, the wide-area light source 132 can be disposed on the lower portion of the substrate 10, on the other side of the substrate 10, to illuminate a wider area than the coaxial light source 131.

[0061] Light emitted by these two light sources 130 passes through the aperture 20 and forms an optical image through optical phenomena such as diffraction and interference with the refracted light beams. Thus, the camera 120 can obtain an image of the substrate 10, including an image of the aperture 20, which can detect the shape and position of the aperture 20. Specifically, the optical image can be obtained based on light incident on the camera 120 from the outer area outside the outer diameter 21, the tapered area between the outer diameter 21 and the inner diameter 22, and the pupil area inside the inner diameter 22, respectively, through optical phenomena such as reflection, diffraction, and interference.

[0062] At this point, while the area outside outer diameter 21, representing the surface of substrate 10, has a high reflectivity for illumination light incident perpendicularly to the surface, the tapered area between outer diameter 21 and inner diameter 22, being inset and tilted from the surface of substrate 10, has a relatively low reflectivity for illumination light. This difference in reflectivity creates a significant difference in grayscale levels between the inner and outer areas in the image, based on outer diameter 21. Therefore, outer diameter 21 can be identified based solely on illumination light from coaxial light source 131. In contrast, the tapered area between outer diameter 21 and inner diameter 22, due to its inset and tilted nature from the surface of substrate 10, has a low reflectivity for illumination light from coaxial light source 131, making it difficult to distinguish from the pupil area within inner diameter 22.

[0063] Therefore, according to an embodiment, a wide-area light source 132 can be disposed on the other side of the camera 120 and the coaxial light source 131, thereby enabling identification of the inner diameter 22. Specifically, the illumination light from the wide-area light source 132 enters the camera 120 through the aperture 20, thereby creating a grayscale difference between the tapered region between the outer diameter 21 and the inner diameter 22 and the pupil region inside the inner diameter 22, thereby enabling identification of the inner diameter 22.

[0064] Therefore, the hole detection system 100 can obtain an image of the substrate 10 in which the inner and outer grayscale levels of the boundary lines of the outer diameter 21 and the inner diameter 22 differ by more than 10, and based on this, simultaneously detect the outer diameter 21 and the inner diameter 22, thereby shortening the detection time and improving the detection accuracy.

[0065] This is explained in further detail below. If the hole detection system 100 only has a single coaxial light source 131, then, as described above, the cone-shaped area and the pupil area inside the inner diameter 22 in the image of the substrate 10 have similar grayscale levels. Therefore, only the outer diameter 21 can be detected, and the inner diameter 22 cannot be detected. To detect the inner diameter 22, the coaxial light source 131 is moved toward the side facing the camera 120 and illuminates the lower portion of the substrate 10. The camera 120 collects the light that passes through the pupil area inside the inner diameter 22, thereby detecting the inner diameter 22. However, in this case, the outer diameter 21 and inner diameter 22 must be detected in two separate steps, which increases detection time and can lead to errors in the two detection processes, reducing detection accuracy.

[0066] In contrast, the hole detection system 100 of the present invention can use the coaxial light source 131 and the wide-area light source 132 to obtain clear hole images for inner and outer diameters, and therefore has the advantage of being able to solve the above-mentioned problems.

[0067] On the other hand, the inspection module 140 detects the hole 20 based on the image captured by the camera 120 and may include a processor for analyzing the image. According to an embodiment, the inspection module 140 may extract the boundary between the inner diameter 22 and the outer diameter 21, detect whether the inner diameter 22 and the outer diameter 21 of the hole 20 are formed, and detect the shape of the inner diameter 22 and the outer diameter 21, thereby determining whether the hole 20 is a high-quality product. According to an embodiment, to further clarify the boundary between the inner diameter 22 and the outer diameter 21, the inspection module 140 may process the image of the substrate 10 to increase the grayscale difference between the inner and outer grayscale levels of the boundary area between the inner diameter 22 and the outer diameter 21.

[0068] Furthermore, the inspection module 140 can measure the distance between the holes 20 to determine whether the holes 20 are of high quality. For example, the center of the hole 20 can be determined based on at least one of the inner diameter 22 and the outer diameter 21. The distance 23 between the holes 20 can then be measured based on the center of each hole 20 to analyze the alignment of the holes 20 and determine whether the holes 20 are of high quality.

[0069] Related to this, Figure 4 FIG. 1 is an exemplary diagram of a substrate 10 having a plurality of holes 20 according to an embodiment of the present invention. Figure 4 The substrate 10 may be formed with a location on the substrate 10, for example, global marks 41, 42, 43 corresponding to corners of the substrate 10 and alignment marks 50 corresponding to corners of a group 30 formed by the plurality of holes 20, or may be linked to another coordinate structure for forming the global marks 41, 42, 43 and alignment marks 50. For example, when a group 30 formed by the plurality of holes 20 forms a quadrilateral, the alignment marks 50 may be formed at locations corresponding to the four corners of the group 30.

[0070] Thus, the detection module 140 can measure the relative position of the alignment mark 50 based on the global marks 41 , 42 , and 43 , and can also measure the position of each hole 20 included in a group 30 based on the alignment mark 50 .

[0071] According to an embodiment, the global marks 41, 42, 43 and the alignment mark 50 may be formed by a plurality of dots or circles arranged radially. For example, the global marks 41, 42, 43 and the alignment mark 50 may be formed by a dot or circle arranged at the center and a plurality of dots or circles arranged at equal intervals in all directions with the dot or circle arranged at the center as the center.

[0072] In this regard, the inspection module 140 may include an image processing unit (not shown) that processes an image of the substrate 10 based on the global marks 41 , 42 , 43 and the alignment mark 50 .

[0073] According to an embodiment, the image processing unit can determine whether the image of the substrate 10 is distorted based on the global marks 41, 42, 43 and the alignment marks 50. Specifically, the image processing unit can measure the positions and spacing of the global marks 41, 42, 43 and the alignment marks 50, the distortion of the points or circles included in the global marks 41, 42, 43 and the alignment marks 50, or compare the sizes of the points or circles included in the global marks 41, 42, 43 and the alignment marks 50. Based on this, distortion such as tilt or twist of the image can be determined and corrected.

[0074] At this point, the image processing unit can perform an affine transformation, which changes the overall image by changing the arrangement of pixels within the image. For example, the position of each pixel within the image can be changed, and the image can be translated or rotated. This allows the unit to detect image distortion, such as tilt or twist, based on global markers 41, 42, and 43 and alignment marker 50, and to measure the degree of distortion to correct it. Furthermore, the unit can correct distortion by resizing or adjusting the image ratio.

[0075] Furthermore, when the camera 120 obtains multiple images of a substrate 10 divided into predetermined regions, the image processing unit can merge the multiple divided images based on the global marks 41, 42, 43 and the alignment mark 50 to obtain an image of the entire substrate 10. For example, the image processing unit can determine the relative positions of the multiple images based on the global marks 41, 42, 43 and the alignment mark 50 and merge the multiple images.

[0076] Furthermore, the image processing unit can perform affine transformations on each of the multiple segmented images based on the global marks 41, 42, 43 and the alignment mark 50, and can merge them. In this case, the image processing unit can perform affine transformations on each of the multiple segmented images and merge them to make them consistent with CAD. In this case, CAD is a general term for the CAD file itself, the CAD image after transforming the CAD file, and the data extracted from the CAD file or CAD image. The data extracted from the CAD file or CAD image includes, for example, information that can confirm the relative positions between the multiple segmented images, and as an example, can include coordinate information of the global marks 41, 42, 43 and the alignment mark 50 included in the CAD file or CAD image. Thus, the image processing unit can perform affine transformations and merge them to obtain an image of the entire substrate 10, so that the global marks 41, 42, 43 and the alignment mark 50 included in the multiple images are consistent with the global marks 41, 42, 43 and the alignment mark 50 included in the CAD.

[0077] Thus, the inspection module 140 can confirm whether the holes 20 are of high quality based on the image of the substrate 10. For example, the inspection module 140 can determine whether the positions of the holes 20 are appropriate based on the entire image of the substrate 10. Specifically, the inspection module 140 can detect the positions of a group 30 formed by the plurality of holes 20 based on the entire image of the substrate 10. In this case, detecting the position of a group 30 comprising the plurality of holes 20 can include detecting the alignment of the group 30 formed by the plurality of holes 20, such as the position of the group 30 formed by the plurality of holes 20 within the substrate 10, the distance between the groups 30, and the relative orientation of the group 30 with respect to the global marks 41, 42, and 43.

[0078] Specifically, the detection module 140 can detect the position of each hole 20 included in a group 30 formed by a plurality of holes 20. The detection module 140 can assign coordinates to each hole 20 based on the alignment marks 50 corresponding to each corner of the group 30, and detect the position of each hole 20 based on the assigned coordinates. Furthermore, the detection module 140 can extract the directional components of the group 30 formed by the plurality of holes 20 based on the alignment marks 50, and extract the relative directions of the global marks 41, 42, and 43 formed by the extracted directional components, to detect the alignment status of the group 30 formed by the plurality of holes 20.

[0079] Then, Figure 5 FIG. 1 is a top view of a hole detection system 100 for illustrating an embodiment of the present invention.

[0080] Reference Figure 5The substrate 10 can be moved by the substrate moving module 111, and the camera 120 can be moved by the camera moving module 150 to obtain an image of the substrate 10. Furthermore, a wide-area light source 132 can be disposed on the other side of the camera 120 relative to the substrate 10. In this case, the wide-area light source 132 can be disposed perpendicular to the camera 120.

[0081] Specifically, the camera movement module 150 reciprocates the camera 120 in a first direction x1 parallel to the substrate 10. Furthermore, the substrate movement module 111 moves the substrate 10 in a second direction x2 parallel to the substrate 10 and perpendicular to the first direction x1. To this end, the substrate movement module 111 may include multiple linear drive modules (not shown) positioned on either side of the substrate 10 to move the substrate 10. This allows the camera 120 to capture multiple images of a substrate 10 divided into defined regions, ultimately enabling quick and easy acquisition of images of the entire substrate 10.

[0082] Furthermore, in order to continuously provide coaxial light while the camera 120 is moving, the camera moving module 160 may move the coaxial light source 131 simultaneously with the camera 120 .

[0083] Modes for Carrying Out the Invention

[0084] According to an embodiment, the wide-area light source 132 may include a line light source, which is arranged to extend parallel to the first direction x1 in which the camera 120 reciprocates. In this case, the line light source may be arranged on a vertical line with the camera 120.

[0085] Related to this, Figure 6 FIG. 1 is an exemplary diagram for illustrating the light source 130 of the hole detection system 100 according to an embodiment of the present invention.

[0086] Reference Figure 6 The wide-area light source 132 can be formed by a line light source 332 and disposed on the other side of the camera 120 with the substrate 10 as the center. According to an embodiment, the line light source 332 can illuminate an area of ​​(length corresponding to the width of the substrate) * (width corresponding to the FOV of the camera) relative to the substrate 10. The FOV refers to the field of view of the camera 120.

[0087] At this time, the length corresponding to the width of the substrate 10 can be a length corresponding to one of the horizontal width or vertical width of the substrate 10. According to an embodiment, it can be the width of the substrate 10 in a direction parallel to the first direction x1 in which the camera 120 reciprocates on the substrate 10, or the width of an area in which a hole 20 is formed in the substrate 10 in a direction parallel to the first direction x1.

[0088] Furthermore, the length corresponding to the FOV of the camera 120 can be the length corresponding to the area of ​​the substrate 10 that the camera 120 photographs at one time according to the FOV of the camera 120. For example, it can be the length in a direction parallel to the second direction x2 of the area of ​​the substrate 10 that the camera 120 photographs at one time according to the FOV of the camera 120.

[0089] As described above, the line light source 332 can illuminate an area of ​​(length corresponding to the width of the substrate) * (width corresponding to the FOV of the camera) relative to the substrate 10. Thus, the line light source 332 can illuminate the area of ​​the substrate 10 corresponding to the image obtained by the camera 120 while performing reciprocating motion.

[0090] In some embodiments, the wide-area light source 132 may include a surface light source 432 , and the surface light source 432 is configured to illuminate the entire area of ​​the substrate 10 .

[0091] Related to this, Figure 7 FIG. 1 is an exemplary diagram for illustrating a light source 130 of a hole detection system 100 according to another embodiment of the present invention.

[0092] Reference Figure 7 The wide-area light source 132 can be formed by a surface light source 432 and arranged on the other side of the camera 120 with the substrate 10 as the center. In this case, the surface light source 432 and the camera 120 are arranged side by side on the substrate 10 in a vertical line and can illuminate an area corresponding to the total area of ​​the substrate 10.

[0093] In an embodiment of the present invention, Figure 6 As shown, when the wide-area light source 132 is composed of a line light source 332, light can be concentrated on a relatively narrow area. Therefore, it has the advantages of excellent optical rotation performance, can obtain a clear image (i.e., contour line) of the inner diameter 22 of the hole 20, and reduce the manufacturing cost of the hole detection system 100.

[0094] In an embodiment of the present invention, Figure 7 As shown, when the wide-area light source 130 is composed of a surface light source 432, light can be irradiated to the entire area of ​​the substrate 10. Therefore, although the illumination performance is relatively reduced, there is no need to make the scanning area of ​​the camera 120 and the illumination area of ​​the wide-area light source 132 consistent, and the structure of the hole detection system 100 can be simplified.

[0095] As described above, the hole detection system 100 of the present invention has a line light source 332 or a surface light source 432 as a coaxial light source 131 arranged coaxially with the camera 120 based on the substrate 20, and a wide-area light source 132 arranged on the other side of the camera 120. Therefore, it has the advantage of being able to simultaneously measure the inner diameter 22 and the outer diameter 21 of the hole.

[0096] In particular, the coaxial light source 131 is constructed in a manner that can move together with the camera 120. The line light source 332 in the wide-area light source 132 illuminates an area of ​​(length corresponding to the width of the substrate) * (width corresponding to the FOV of the camera), and the surface light source 432 has the characteristic of illuminating the front surface of the substrate 10. Therefore, the inner diameter 22 and the outer diameter 21 of the hole 20 can be quickly detected only by moving the coaxial light source 131 and the camera 120 without moving the line light source 332 or the surface light source 432.

[0097] Furthermore, the line light source 332 or the surface light source 432 can provide sufficiently bright light so that the grayscale levels inside and outside the inner diameter 22 differ by more than 10 in the image of the substrate 10. Therefore, the inner area of ​​the inner diameter 22 (i.e., the pupil area) and the outer area of ​​the inner diameter 22 (i.e., the conical area) can be clearly distinguished. Thus, various inspections can be performed on the hole 20, such as the shape, size, position of the inner diameter 22, deformation of the inner diameter 22 and the outer diameter 21, etc.

[0098] Then, Figure 8 FIG. 1 is a sequence diagram for illustrating a hole detection method according to an embodiment of the present invention.

[0099] Reference Figure 8 In the hole detection method performed by the hole detection system 100, a coaxial light source 131 and a wide-area light source 132 are used to illuminate the substrate 10. The coaxial light source 131 is positioned on the same side as the camera 120 with respect to the substrate 10, and the wide-area light source 132 is positioned on the other side of the camera 120 and illuminates a wider area than the coaxial light source 131 (step S801).

[0100] At this time, the wide-area light source 132 may include a line light source 130, which is arranged to extend side by side with the first direction x1 in which the camera 120 reciprocates. According to an embodiment, the line light source 130 can illuminate an area of ​​(length corresponding to the width of the substrate 10) * (width corresponding to the FOV of the camera 120).

[0101] As another embodiment, the wide-area light source 132 may include a surface light source 130 , and the surface light source 130 illuminates an area corresponding to the total area of ​​the substrate 10 .

[0102] Furthermore, the hole detection system 100 may support the camera 120 at a predetermined distance from the substrate 10 through the camera moving module 150 , and may reciprocate the camera 120 in a first direction x1 parallel to the substrate 10 .

[0103] Furthermore, the hole detection system 100 can move the substrate 10 according to the movement of the camera 120 , and can move the substrate 10 in a second direction x2 that is parallel to the substrate 10 and perpendicular to the first direction x1 .

[0104] Furthermore, the hole detection system 100 may use the camera 120 to obtain an image of the substrate 10 (step S802 ). In this case, the image of the substrate 10 may include an image of the hole 20 , and the grayscale levels inside and outside the boundary area of ​​the inner diameter 22 may differ by more than 10.

[0105] Furthermore, when the hole detection system 100 obtains an image of the substrate 10 , as the camera 120 and the substrate 10 move in the first direction x1 or the second direction x2 , the camera 120 can obtain multiple images that divide the substrate 10 into specified areas.

[0106] Furthermore, the hole detection system 100 may detect the holes 20 based on the obtained image of the substrate 10 (step S803 ).

[0107] According to an embodiment, the hole detection system 100 may process an image of the substrate 10 based on the global marks 41 , 42 , 43 corresponding to a location of the substrate 10 and the alignment mark 50 corresponding to each corner of a group 30 of holes 20 .

[0108] At this time, the global marks 41 , 42 , 43 and the alignment mark 50 can be radially arranged as multiple points or circles and formed on the substrate 10 itself. According to an embodiment, they can be formed on another coordinate structure and attached to the substrate 10 .

[0109] According to an embodiment, the hole detection system 100 can determine whether the image of the substrate 10 is distorted based on the global marks 41 , 42 , 43 and the alignment mark 50 , correct the image of the substrate 10 , and detect whether the hole 20 is of high quality based on the corrected image of the substrate 10 .

[0110] For example, the hole detection system 100 may detect at least one of the positions of a group 30 formed by a plurality of holes 20 and the positions of the holes 20 included in the group 30 based on the global marks 41 , 42 , 43 and the alignment mark 50 .

[0111] Furthermore, the hole detection system 100 can merge a plurality of images obtained by the camera 120 and divided into predetermined areas based on the global marks 41 , 42 , 43 and the alignment mark 50 , and can obtain an image of the entire substrate 10 .

[0112] For example, the hole detection system 100 may perform affine transformation on the plurality of segmented images based on the global marks 41 , 42 , 43 and the alignment mark 50 , and merge them to be consistent with CAD, thereby obtaining an image of the entire substrate 10 .

[0113] The hole detection system 100 of the present invention moves the line camera back and forth in the first direction x1 while moving the substrate 10 in the second direction x2 and obtains an image of the entire substrate 10. Therefore, it has the advantages of shortening the detection time and easily achieving detection even if a substrate 10 of any size is input.

[0114] The embodiments of the present invention are further described in detail above with reference to the attached drawings, but the present invention is not limited to such embodiments, and various modifications can be implemented without departing from the technical idea of ​​the present invention. Therefore, the embodiments disclosed in the present invention are not used to limit the technical idea of ​​the present invention, but to illustrate the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited to such embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all aspects and not restrictive. The scope of protection of the present invention should be interpreted by the scope of the patent application, and all technical ideas that are within the equivalent scope should be interpreted as included in the scope of protection of the present invention.

Claims

1. A hole detection system for a substrate having a hole, comprising: a substrate supporting device, configured to support the substrate; a camera, disposed above or below the substrate, to obtain an image of the substrate; a coaxial light source, based on the substrate, and arranged on the same side as the camera; a wide-area light source, disposed on the other side of the camera and illuminating a wider area than the coaxial light source; as well as The detection module detects the hole based on the image of the substrate obtained by the camera.

2. The hole detection system according to claim 1, wherein: The camera moving module is configured to support the camera at a predetermined distance from the substrate and to enable the camera to reciprocate in a first direction parallel to the substrate. The substrate supporting device further includes a substrate moving module configured to move the substrate toward a second direction that is parallel to the substrate and perpendicular to the first direction.

3. The hole detection system according to claim 2, wherein: The substrate moving module includes a plurality of linear driving modules, and the plurality of linear driving modules are respectively arranged on both sides of the substrate, so that the substrate moves linearly.

4. The hole detection system according to claim 1, wherein: The wide-area light source includes a line light source, and the line light source is arranged to extend side by side with the first direction in which the camera performs reciprocating motion.

5. The hole detection system according to claim 4, wherein: The line light source illuminates an area of ​​(length corresponding to the width of the substrate)*(width corresponding to the FOV of the camera).

6. The hole detection system of claim 1 , wherein: The wide-area light source includes a surface light source that illuminates a region corresponding to the total area of ​​the substrate.

7. The hole detection system of claim 1 , wherein: The inspection module includes an image processing unit that processes an image of the substrate based on a global mark corresponding to a location on the substrate and alignment marks corresponding to corners of a group formed by the holes.

8. The hole detection system of claim 7, wherein: The image processing unit detects at least one of a position of the one group and a position of the holes included in the one group based on the global mark and the alignment mark.

9. The hole detection system of claim 7, wherein: The global mark and the alignment mark are formed by arranging a plurality of dots or circles in a radial pattern, The image processing unit determines whether the image of the substrate is distorted based on the global mark and the alignment mark, and corrects the image of the substrate.

10. The hole detection system of claim 7, wherein: The camera obtains a plurality of images of the substrate divided into predetermined areas. The image processing unit combines the plurality of divided images based on the global mark and the alignment mark, and obtains an image of the entire substrate.

11. The hole detection system of claim 10, wherein: The image processing unit performs affine transformation on the plurality of segmented images based on the global mark and the alignment mark, and merges the images so as to be consistent with CAD, thereby obtaining an image of the entire substrate.

12. The hole detection system of claim 1, wherein: The camera obtains an image of the substrate including both the inner and outer diameters of the hole, The inspection module determines whether the hole is a quality product based on the image of the substrate.

13. The hole detection system of claim 1 , wherein: The grayscale levels of the inner and outer sides of the boundary line region of the inner diameter in the image of the substrate differ by 10 or more.

14. A hole detection method, as a hole detection method performed by the hole detection system of claim 1, comprising: The step of illuminating the substrate using a coaxial light source and a wide-area light source, wherein the coaxial light source is disposed on the same side of the substrate as the camera, and the wide-area light source is disposed on the other side of the camera and illuminates a wider area than the coaxial light source; a step of obtaining an image of the substrate using the camera; as well as The step of detecting the holes based on the obtained image of the substrate.

15. The hole detection method according to claim 14, wherein: The steps for performing the detection include: Correcting the image of the substrate based on a global mark corresponding to a location on the substrate and alignment marks corresponding to corners of a group formed by the holes; and The step of detecting whether the hole is a quality product based on the corrected image of the substrate.

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