Chip inspection device

Abstract

To provide a chip inspection device for determining the propriety of a chip in a ridge line section of an inspection object.SOLUTION: A chip inspection device includes: a detection section for detecting a chip area expressing an area of a chip on the basis of a difference between an actual ridge line that is a ridge line of a first area in which an image area of an inspection object is expressed by a single color when an image including the inspection object with a chip in the ridge line section is inputted, and a reference ridge line that is a ridge line of a second area in which a part of a chip appearing in the first area is buried by the single color; and a determination section for determining the propriety of the chip on the basis of length in which a difference to the length of a partial ridge line in the reference ridge line corresponding to the chip area is larger from among lengths of respective sides of a rectangular area in which the chip area is approximated to a rectangle.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a chipping inspection device. [Background technology]

[0002] There is known a technique for detecting defects in the outer periphery (bevel portion) of a semiconductor wafer, such as a wafer edge that is a curved circular arc, from an image with high accuracy (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-109690 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, because the above-mentioned technique uses the angle of the wafer edge, if the detection target portion is not on the circumference, it cannot detect defects. For example, when detecting a chip on the edge of an object to be inspected, which is not on the circumference, and judging whether the chip is appropriate or not, the above-mentioned technique cannot judge whether the chip is appropriate or not.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a chip inspection device that determines whether or not there is a chip on the edge of an object to be inspected. [Means for solving the problem]

[0006] The chip inspection device of the present invention has a detection unit that, when an image is input that includes an inspection object having a chip in an edge portion, detects a chipped area representing the chipped area based on the difference between an actual edge line, which is the edge line of a first area that represents the image area of ​​the inspection object in a single color, and a reference edge line, which is the edge line of a second area in which the chipped area that appears in the first area is filled in with the single color, and a judgment unit that judges whether the chip is appropriate or not based on the greater difference between the length of each side of a rectangular area that approximates the chipped area to a rectangle and the length of a partial edge line in the reference edge line that corresponds to the chipped area, among the lengths of each side of the rectangular area. Effect of the Invention

[0007] According to the present invention, it is possible to determine whether or not there is a chip on the edge of an object to be inspected. [Brief description of the drawings]

[0008] [Figure 1] 1A is a diagram for explaining an example of inspection for edge chipping, and FIG. 1B is an example of the hardware configuration of a control device. [Diagram 2] 5 is a flowchart showing an example of the operation of the control device. [Diagram 3] 1A to 1L are diagrams illustrating an example of an inspection flow. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] As shown in FIG. 1(a), the imaging device 10 images an inspection object 20. The imaging device 10 is disposed above the inspection object 20 (specifically, in the zenith direction). Therefore, the imaging device 10 images the top surface of the inspection object 20. The imaging device 10 may be disposed in front of the inspection object 20. In this case, the imaging device 10 images the front surface of the inspection object 20. Defects such as edge chips 21 and 22 exist on a ridge line portion 20E of the inspection object 20.

[0011] The imaging device 10 may be a video camera that captures moving images, or a still camera that captures still images. The inspection object 20 is placed on a floor surface, an inspection table, or the like. The inspection object 20 may be an engine part mounted on a vehicle, or may be a product or part other than an engine part. Examples of engine parts include a cylinder head, a cylinder block, and an oil pan. Examples of products and parts other than engine parts include daily necessities, furniture, cooking utensils, stationery, electrical appliances, and parts thereof.

[0012] The imaging device 10 is connected to a terminal device 30, such as a PC (Personal Computer). More specifically, the imaging device 10 is connected to a control device 100 provided in the terminal device 30. The control device 100 is an example of a chipping inspection device. The control device 100 is also connected to an input device 31 and a display device 32. The input device 31 is, for example, a keyboard or a mouse. The display device 32 is, for example, a liquid crystal display.

[0013] When a user 50 who is checking whether the edge chipping 21, 22 of the inspection object 20 is appropriate operates the input device 31, the input device 31 outputs an electrical operation signal corresponding to the operation to the control device 100. When the control device 100 detects the operation signal, it controls the operation of the imaging device 10 and the display device 32 based on the operation signal. For example, the control device 100 requests the transmission of a captured image including the inspection object 20 captured by the imaging device 10 to the control device 100. As a result, the captured image is input to the control device 100. In addition, the control device 100 requests the display device 32 to display a confirmation screen 33 for checking whether the edge chipping is appropriate. As a result, the confirmation screen 33 appears on the display device 32.

[0014] As shown in FIG. 1(b), the control device 100 includes a CPU (Central Processing Unit) 100A as a processor, and a RAM (Random Access Memory) 100B and a ROM (Read Only Memory) 100C as memories. The control device 100 includes an input / output I / F (Interface) 100D and a HDD (Hard Disk Drive) 100E. Instead of the HDD 100E, a SSD (Solid State Drive) may be adopted. The CPU 100A to the HDD 100E are connected to each other by an internal bus 100F. In other words, the control device 100 can be realized by a computer.

[0015] The imaging device 10, the input device 31, and the display device 32 are connected to the input / output I / F 100D. The input / output I / F 100D is equipped with, for example, a USB port and a display port. The CPU 100A temporarily stores the inspection program stored in the ROM 100C and the HDD 100E in the RAM 100B. The CPU 100A can realize a detection unit and a determination unit by executing the stored edge chipping inspection program. The edge chipping inspection program may be one according to a flowchart described later.

[0016] The operation of the control device 100 will be described with reference to Figures 2 and 3. The control device 100 may execute control not to display at least one of the states in Figures 3(b) to 3(l) on the display device 32.

[0017] First, as shown in FIG. 2, the CPU 100A waits until a captured image is input (step S1: NO). When the captured image is input (step S1: YES), the CPU 100A generates a real area (step S2). For example, a still image captured by the imaging device 10 is input to the control device 100 as a captured image in a real-life state. When the captured image is input to the control device 100, the CPU 100A displays an inspection image IM on the confirmation screen 33, in which the background is filled in with a solid black color, as shown in FIG. 3(a). In the inspection image IM, the top surface of the inspection object 20 appears in a real-life state. On the other hand, the edge chips 21 and 22 appear almost as part of the background due to their dark appearance.

[0018] When the user 50 operates the input device 31 to press a predetermined button in the confirmation screen 33, the CPU 100A generates the real area 23 as a first area, as shown in Fig. 3(b). More specifically, the CPU 100A generates the real area 23 by filling the top surface of the inspection object 20 with a single color other than white and black (for example, gray such as light gray or dark gray) by binarization processing or the like.

[0019] When the process of step S2 is completed, the CPU 100A generates an ideal region 24 as a second region (step S3), as shown in Fig. 2 and Fig. 3(c). More specifically, the CPU 100A generates the ideal region 24 representing the ideal top surface of the inspection object 20 without the edge chips 21, 22 by a filling process that fills in the edge chips 21, 22 with the same monochromatic color as the monochromatic color described above. The CPU 100A may execute the processes of steps S2 and S3 in parallel.

[0020] When the process of step S3 is completed, as shown in Fig. 2 and Fig. 3(d), the CPU 100A detects edge chipping regions A and B (step S4). More specifically, based on the difference between the actual edge line 23E, which is the edge line of the actual region 23, and the reference edge line 24E, which is the edge line of the ideal region 24, the edge chipping regions A and B, which represent the image regions of the edge chips 21 and 22, are detected. The actual edge line 23E corresponds to the outline of the actual region 23, i.e., the boundary line between the actual region 23 and the background portion. The reference edge line 24E corresponds to the outline of the ideal region 24, i.e., the boundary line between the ideal region 24 and the background portion.

[0021] When the process of step S4 is completed, the CPU 100A executes a rectangular approximation process (step S5) as shown in Fig. 2. The rectangular approximation process is a process for approximating the non-rectangular edge chipped areas A and B to a rectangle. As a result, as shown in Fig. 3(e), the edge chipped area A is approximated to a rectangular area 25A that contains the edge chipped area A in the minimum rectangle, and the edge chipped area B is approximated to a rectangular area 25B that contains the edge chipped area B in the minimum rectangle.

[0022] When the process of step S5 is completed, the CPU 100A acquires the size (step S6), as shown in Fig. 2. More specifically, as shown in Figs. 3(e) and (f), the CPU 100A acquires the short side length S representing the length of the short side and the long side length L representing the length of the long side of each of the rectangular regions 25A and 25B as the size. For example, the CPU 100A acquires "1 mm" as the short side length S of the rectangular region 25A, and "1.2 mm" as the long side length L. Similarly, the CPU 100A acquires "0.8 mm" as the short side length S of the rectangular region 25B, and "1.2 mm" as the long side length L.

[0023] When the process of step S6 is completed, the CPU 100A generates the boundary area 26 (step S7) as shown in Fig. 2 and Fig. 3(g). The boundary area 26 is the above-mentioned single-color area in which a line identical to or very similar to the reference edge line 24E is given a predetermined width that allows measurement of the widths of the edge chips 21, 22. The CPU 100A may execute the process of step S7 immediately after executing the process of step S3.

[0024] When the process of step S7 is completed, the CPU 100A superimposes a white line 27 on the inspection image IM (step S8), as shown in Fig. 2 and Fig. 3(h). More specifically, the CPU 100A paints the boundary area 26 white, and superimposes the white-painted boundary area 26 as the white line 27 so as to match the outline of the top surface of the inspection object 20 appearing in the inspection image IM. In this way, the inspection image IM is edited into a new image Im that includes the actual top surface of the inspection object 20, the white line 27 superimposed on the outline of the top surface, and a black background portion.

[0025] When the process of step S8 is completed, as shown in Fig. 2 and Fig. 3(i), the CPU 100A cuts out the image based on the rectangular regions 25A and 25B (step S9). For example, the CPU 100A cuts out a partial region 28A including a part of the white line 27 from the new image Im based on the positional relationship between the rectangular region 25A and the new image Im edited from the original inspection image IM. Similarly, the CPU 100A cuts out a partial region 28B including a part of the white line 27 from the new image Im based on the positional relationship between the new image Im and the rectangular region 25B. Note that the part of the white line 27 is an example of a partial edge line.

[0026] When the process of step S9 is completed, as shown in Figures 2 and 3(j), the CPU 100A acquires the white line length W, which indicates the length of a portion of the white line 27 in the partial areas 28A and 28B (step S10). For example, the CPU 100A measures the white line length W in the partial area 28A and acquires the white line length "1 mm." The CPU 100A also measures the white line length W in the partial area 28B and acquires the white line length "1.2 mm."

[0027] When the process of step S10 is completed, as shown in Fig. 2, CPU 100A judges whether or not the short side length S and the white line length W are the same (step S11). That is, as shown in Fig. 3(k), CPU 100A judges whether or not there is a difference between the white line length W and the short side length S. As shown in Fig. 2, if the short side length S and the white line length W are the same (step S11: YES), CPU 100A determines the depth length to be the long side length L (step S12). Conversely, if the short side length S and the white line length W are different (step S11: NO), CPU 100A determines the depth length to be the short side length S (step S13).

[0028] To explain in more detail, for example, in partial region 28A, two directions of edge chip 21 in inspection object 20 can be identified by the width parallel to reference edge line 24E of edge chip region A and the depth perpendicular to reference edge line 24E. The depth can be said to be the depth dug down toward the center of inspection object 20. In this way, the width direction and the depth direction (or depth direction) of edge chip 21 can be identified.

[0029] Here, as shown in FIG. 3(k), in the case of the chipped edge region A, the white line length W corresponding to the chipped edge region A and the short side length S corresponding to the rectangular region 25A are both the same at "1 mm", and there is no difference between the white line length W and the short side length S. On the other hand, since the long side length L is "1.2 mm", there is a difference of "0.2 mm" between this white line length W and the long side length L corresponding to the rectangular region 25A. In other words, the difference between the white line length W and the long side length L is greater than the difference between the white line length W and the short side length S. It can also be said that the difference between the white line length W and the short side length S is smaller than the difference between the white line length W and the long side length L. In this way, these two differences are compared, and the depth direction is determined based on the length with the larger difference (i.e., either the long side length L or the short side length S). ​​In the case of the chipped edge region A, the depth direction is determined based on the long side length L. As a result, the depth length is determined to be the long side length L. In this case, the portion of the white line 27 in the partial region 28A corresponds to the width of the edge chipping 21.

[0030] On the other hand, in the case of the chipped edge region B, the white line length W corresponding to the chipped edge region B is "1.2 mm", and the short side length S corresponding to the rectangular region 25B is "0.8 mm". That is, the white line length W is "0.4 mm" longer than the short side length S, and there is a difference between the white line length W and the short side length S. On the other hand, since the long side length L corresponding to the rectangular region 25B is "1.2 mm", there is no difference between the white line length W and the long side length L. That is, the difference between the white line length W and the long side length L is smaller than the difference between the white line length W and the short side length S. In other words, the difference between the white line length W and the short side length S is larger than the difference between the white line length W and the long side length L. As a result, in the case of the chipped edge region B, the depth direction is specified based on the short side length S. As a result, the depth length is determined to be the short side length S. In this case, the portion of the white line 27 in the partial region 28B corresponds to the width of the chipped edge 22.

[0031] In this way, the CPU 100A measures and obtains the white line length W and the short side length S and long side length L of the rectangular areas 25A, 25B, and compares the differences between them to determine the magnitude of the difference. This allows the CPU 100A to identify the depth direction of the edge notches 21, 22, and also to determine the depth length of the edge notches 21, 22.

[0032] When the processing of steps S12 and S13 is completed, the CPU 100A executes a suitability judgment of the standard of the edge notches 21 and 22 and the length of the depth (step S14) and ends the processing, as shown in Fig. 2 and Fig. 3(l). For example, 1 mm is set as the suitability threshold of the standard of the edge notches 21 and 22, and the CPU 100A judges that the standard is met if it is less than the suitability threshold.

[0033] In this case, CPU 100A judges edge chip 21, which has a depth length of 1.2 mm, to be in compliance with the standard as "NG (non-compliant)". On the other hand, CPU 100A judges edge chip 22, which has a depth length of 0.8 mm, to be in compliance with the standard as "OK (compliant)". In this way, even if there are multiple edge chips 21, 22 on inspection object 20, control device 100 can easily judge compliance with the standard by performing a matrix-like calculation all at once, without being limited by the number of edge chips. CPU 100A may output the result of the compliance judgment to confirmation screen 33, or may output it to an electronic file in CSV (Comma Separated Values) format or the like.

[0034] Although the preferred embodiment of the present invention has been described above in detail, the present invention is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims. For example, in the above-mentioned embodiment, the combined use of the imaging device 10 and the terminal device 30 has been described, but instead of the combined use of the imaging device 10 and the terminal device 30, a smart device with a camera (such as a smartphone or a tablet terminal) may be used.

[0035] Also, the inspection image IM and the edited image Im may be stored in advance in a semiconductor memory such as a flash memory. In this case, the inspection image IM and the edited image Im may be read into the control device 100. Furthermore, an image of a cracked concrete wall may be prepared as the inspection image IM and the edited image Im, and the control device 100 may measure the width of the crack to determine the depth direction and the length of the depth. Furthermore, the depth direction and the length of the depth may be determined by measuring the width of a nest hole from an image of a cross-section of an insect nest such as an ant. [Explanation of symbols]

[0036] 10. Imaging device 20 Inspection object 21,22 Edge chipping 23 Real Domain 23E Real Ridgeline 24 Ideal area 24E Reference ridge 27 White Line 30 Terminal Equipment 100 Control device A,B Edge chipping area

Claims

[Claim 1] a detection unit which, when an image including an object to be inspected having a chip in an edge portion is input, detects a chipped region representing the chipped region based on a difference between an actual edge line which is an edge line of a first region in which an image region of the object to be inspected is represented in a single color and a reference edge line which is an edge line of a second region in which the chipped portion appearing in the first region is filled in with the single color; a determination unit that determines whether the chipping is appropriate based on a larger difference between the length of each side of a rectangular area obtained by approximating the chipping area to a rectangle and the length of a partial edge line of the reference edge line that corresponds to the chipping area; and A chipping inspection device having the above structure.

Images