JP2007003494A - Inspection method of wiring pattern, and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To certainly extract a failure of a wiring pattern, and to increase the yield by enabling determination of a good article when the degree of deformation of the wiring pattern is a degree where a practical problem does not occur. <P>SOLUTION: An imaging means 11 images an image of a mounted substrate 1 where the wiring pattern is formed on a surface of a base made of insulating material. A gray image obtained by the imaging means 11 is binarized by a separating means 21. Regarding a focus region in the binarized image, a region adjusting means 22 alternatively performs contraction processing and expansion processing of a pixel having a pixel value of the wiring pattern. A labeling means 23 attaches a label to a coupling region in the image after the contraction processing or expansion processing, and a comparing means 24 compares the number of designed wiring patterns with the number of labels. When both of them are the same, goodness/badness of the coupling region is inspected by an inspecting means 25. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wiring pattern inspection method and apparatus for inspecting the quality of a wiring pattern mainly using an image of a fine wiring pattern on a mounting substrate on which a semiconductor element is mounted.

  In general, a mounting substrate on which a semiconductor element such as a semiconductor chip is mounted has a metal wiring pattern formed on the surface of a base of a synthetic resin molded product by a thin film forming technique, and this type of wiring pattern is fine. For this reason, it is difficult to visually find a defective part. Therefore, it is considered to detect a defect in the wiring pattern by appearance inspection using an image obtained by imaging the wiring pattern (for example, see Patent Document 1). Types of defects that can be detected by this type of visual inspection include short-circuiting of adjacent wiring patterns, disconnection of wiring patterns, adhesion of foreign matters to the wiring patterns, and scratches and spots on the wiring patterns.

  In the invention described in Patent Document 1, in order to determine whether a wiring pattern is good or bad, a wiring pattern (inspection pattern) to be inspected and a wiring pattern (accepting pattern) to be a template are overlaid to overlap each other. A technique is described in which a part deviating from the acceptance pattern is detected as a defective part candidate, the shape or area of the defective part candidate is extracted as a feature quantity, and the quality is determined by comparing the feature quantity with an inspection standard. Yes.

In addition, there is also described a technique for determining whether or not a wiring pattern is acceptable by comparing information regarding the degree of bending of the outline of a printed pattern to be inspected with reference information registered in advance.
JP-A-8-31580

  However, in the technique using the acceptable pattern, the defect may be missed as described in Patent Document 1, while in the technique using the bending of the contour line, the defect detection frequency increases because the defect is not missed. Even if the degree of deformation of the wiring pattern does not cause a problem in practice, such as a minute defect in the wiring pattern, it will be judged as a defective product, resulting in a decrease in yield. ing.

  The present invention has been made in view of the above-mentioned reasons, and its purpose is to improve the yield so that it can be judged as a non-defective product when the degree of deformation of the wiring pattern does not cause a problem in practical use. In addition, it is an object of the present invention to provide a wiring pattern inspection method and apparatus capable of reliably extracting defects such as disconnection of a wiring pattern.

  The invention of claim 1 is a wiring pattern inspection method, wherein an image of a mounting board in which a wiring pattern is formed on the surface of a base made of an insulating material is picked up by an image pickup means, and the image in the image obtained by the image pickup means It is a candidate for a wiring pattern after separating a wiring pattern and a base using a pixel value for the region of interest and applying either expansion processing or contraction processing to the boundary between the wiring pattern and the base within the region of interest. The number of connected areas is counted, and when the number of candidates counted matches the number of designed wiring patterns, the quality of the wiring pattern is inspected in the connected area that is a candidate for the wiring pattern.

  According to this method, for the region of interest in the image, the area between the wiring pattern and the base is separated and the occupied area of the wiring pattern is reduced or increased by expansion processing or contraction processing. When a portion with a small width dimension is generated, the portion is removed from the image when the area occupied by the wiring pattern is reduced, and conversely, a short circuit occurs in the imaged wiring pattern. When a portion having a large width dimension is generated, the portion is connected in the image when the area occupied by the wiring pattern is increased. As a result, when a constriction that causes a defect in the wiring pattern occurs, the connection area that is a candidate for the wiring pattern is divided, so that the number of connection patterns becomes larger than the number of designed wiring patterns, or the candidate for the wiring pattern. The connected region disappears and the connected region becomes smaller than the number of wiring patterns designed. Further, if there is a portion close enough to cause a defect in the wiring pattern, a plurality of connection regions are connected to one another, so that the number of connection regions is smaller than the number of wiring patterns designed. Therefore, by comparing the number of connection regions that are wiring pattern candidates after the expansion process or the contraction process with the designed number, it is possible to perform a pre-process regarding the quality of the wiring pattern. The wiring pattern determined to be defective in this pre-processing hardly includes a non-defective product, and the defective product can be reliably sorted. Also, when foreign matter is placed on the wiring pattern, it is handled in the image in the same way as when the width dimension of the wiring pattern is narrow, so when the foreign matter is large, the wiring pattern is divided by expansion processing or contraction processing, and the presence of foreign matter Defective products can also be sorted.

On the other hand, the non-defective wiring patterns that are not determined to be defective by the pre-processing are mixed with non-defective products and defective products, but the defective products due to lack of the width dimension of the wiring patterns are removed, so they remain. With regard to wiring pattern candidates, it is only necessary to inspect for the presence or absence of disconnection and the presence or absence of a short circuit, thereby reducing the processing load.

It should be noted that the extent to which the area occupied by the wiring pattern is reduced is such that when the wiring pattern having a width that is allowable as the minimum width of the wiring pattern is contracted, the candidate wiring pattern after contraction becomes a predetermined width dimension or more. Set to

  According to a second aspect of the invention, in the first aspect of the invention, the image obtained by the imaging means is a grayscale image, and the grayscale image is binarized using a threshold value set for the density value of the grayscale image. The wiring pattern and the base are separated by the above.

  According to this method, the wiring pattern made of metal and the base made of insulating material can be easily separated by the difference in reflectance.

  As the threshold for binarization, a constant value defined as a density value between the wiring pattern and the base can be used, or an average value of the density values of the region of interest can be used.

  According to a third aspect of the present invention, in the first aspect of the present invention, the image obtained by the imaging means is a color image, and the value corresponding to the wiring pattern among the two differences of the tristimulus values of the color image It is characterized in that the wiring pattern and the base are separated by binarizing the difference that maximizes the difference from the value corresponding to the base.

  According to this method, the wiring pattern and the base can be separated using the color difference between the color of the wiring pattern and the color of the base. In particular, by using the difference between two of the tristimulus values of the color image, the wiring between the color of the wiring pattern and the base color is reflected, and the wiring is simply set by setting a threshold value for one value. Since the pattern and the base can be separated, the wiring pattern and the base can be reliably separated with a small processing load.

  The threshold for binarization may be a constant value that is defined so that the difference between the tristimulus values is a value between the wiring pattern and the base, or an average value of the differences in the region of interest. it can.

  According to a fourth aspect of the present invention, there is provided a wiring pattern inspection apparatus, wherein an imaging unit that captures an image of a mounting board having a wiring pattern formed on a surface of a base made of an insulating material, and an image in the image obtained by the imaging unit Separation means for separating the wiring pattern and the base using pixel values for the area of interest; area adjustment means for selectively performing expansion processing and contraction processing at the boundary between the wiring pattern and the base within the area of interest; , A labeling means for obtaining a connection area that is a candidate for a wiring pattern after the expansion process or the contraction process, assigning a label to each connection area, and counting the number of labels applied thereto, and the number of labels matches the number of designed wiring patterns And an inspection means for inspecting the quality of the wiring pattern in the connection region which is a candidate for the wiring pattern.

  According to this configuration, the same effect as in the first aspect can be obtained. In addition, since labeling is performed after the expansion process or contraction process of the wiring pattern in the region of interest and the number of designed wiring patterns is compared with the number of labels, there is no possibility that the wiring pattern is broken by this preprocessing. It is possible to easily and reliably sort defective products that are short-circuited in good products or wiring patterns. Here, non-defective products are mixed with non-defective products, but defective products due to lack of width are removed from the wiring pattern. For pattern candidates, the processing load can be reduced by checking the presence or absence of disconnection and the presence or absence of a short circuit.

  According to the present invention, for the region of interest in the image, the area between the wiring pattern and the base is separated and the occupied area of the wiring pattern is reduced or increased by expansion processing or contraction processing. If there is a part with a small width dimension, the area is removed from the image after reducing the area occupied by the wiring pattern by expansion or contraction, and the imaged wiring pattern is defective. If a portion having a width dimension that is large is generated, after the area occupied by the wiring pattern is increased by the expansion process or the contraction process, a plurality of connection regions are connected to one connection region in the region. Therefore, by comparing the number of connection regions that are wiring pattern candidates after the expansion process or the contraction process with the designed number, it is possible to separate the wiring patterns that are clearly defective. Good and defective wiring pattern candidates are mixed, but defective products due to lack of width dimensions are removed from the wiring pattern, so remaining wiring pattern candidates other than width dimensions It is sufficient to reduce the processing load. That is, the wiring pattern that is clearly defective is removed by a simple process based on the expansion process or the contraction process and the number comparison, and only the remaining wiring pattern candidates need to be inspected with high accuracy. Therefore, the yield is improved and the processing load is reduced.

  The inspection object described below is a mounting board on which a semiconductor element is mounted. For example, a mounting board made of MID (Molded Interconnection Device) is used as the inspection object. As shown in FIG. 2, this type of mounting substrate 1 is formed by forming a metal wiring pattern 1b on a base 1a made of a synthetic resin such as a liquid crystal polymer by a thin film forming method. In order to mount a semiconductor element (chip), a fine wiring pattern 1b is formed. For example, the minimum width of the wiring pattern 1b and the interval between adjacent wiring patterns 1b are set to 50 μm, for example.

  When the wiring pattern 1b is inspected for the mounting substrate 1, a plurality of mounting substrates 1 are placed on the pallet 2 and aligned and conveyed as shown in FIG. The pallet 2 is placed on the XY table 3 as shown in FIG. A TV camera 11 as an imaging unit is disposed above the XY table 3, and the field of view of the TV camera 11 is set to a width equal to or less than one mounting substrate 1 placed on the pallet 2. For example, it is set to a field of view capable of imaging one whole mounting board 1 or to a field of view capable of imaging a part of the mounting board 1. Of the plurality of mounting boards 1 placed on the pallet 2, the target mounting board 1 is moved to the front of the TV camera 11 by operating the XY table 3 and is imaged by the TV camera 11. Moreover, what is called a ring light which arrange | positions a light source on a ring and illuminates an imaging | photography object without a shadow is used for the lighting fixture 4 which illuminates the mounting board | substrate 1 used as an imaging object.

  The TV camera 11 can be used to output either a monochrome grayscale image or a color image output. First, the TV camera 11 that outputs a grayscale image will be described. A case where the TV camera 11 that outputs an image is used will be described.

  The grayscale image obtained by the TV camera 11 is temporarily stored in the image memory 12. Here, it is assumed that a digital signal is output from the TV camera 11, but when an analog signal is output, it is converted into a digital signal using an A / D converter. As described above, the grayscale image of the mounting board 1 is stored in the image memory 12, and the image processing unit 20 performs the following processing using this grayscale image.

  The image processing unit 20 includes separation means 21 for binarization by applying an appropriate threshold to the density value of each pixel of the grayscale image. The threshold value set in the separating means 21 is set so that the base 1a and the wiring pattern 1b of the mounting substrate 1 can be separated in the grayscale image. That is, since the reflectance of the base 1a is generally lower than the reflectance of the wiring pattern 1b, the density value of the base 1a is lower than the density value of the wiring pattern 1b in the grayscale image (here, the density value is set to lightness). The brightness is higher as the density value is higher). Therefore, if the density value between the two density values is set as a threshold value, the area of the base 1a and the wiring pattern 1b in the gray image can be separated.

  Although such a threshold value can be set in advance as a constant value, as shown in FIG. 3, a region of interest Dm including the base 1a and the wiring pattern 1b is designated in the grayscale image stored in the image memory 11. Alternatively, the average value of the density values of the pixels included in the region of interest Dm may be used as the threshold value. In this case, the threshold value can be set dynamically for each region of interest Dm, and an appropriate threshold value can be set regardless of imaging conditions and variations in the specifications of the mounting substrate 1.

  As shown in FIG. 4, an image binarized using an appropriate threshold value as described above is an image having two types of areas, an area corresponding to the base 1a and an area corresponding to the wiring pattern 1b. . By the way, even when the width dimension of the wiring pattern 1b is larger than the design value as a whole (hereinafter referred to as “thickness”), there is a problem as a non-defective product if a short circuit with the adjacent wiring pattern 1b is ensured and a breakdown voltage can be secured. In many cases, there is no problem as a non-defective product as long as the current capacity can be secured even when the width dimension of the wiring pattern 1b is generally smaller than the design value (hereinafter referred to as “thinning”). Similarly, a location 1c where the width dimension of a part of the wiring pattern 1b is larger than the design value as shown in FIG. 5 (hereinafter referred to as “excess part”) or a part of the wiring pattern 1b as shown in FIG. In some cases, a location 1d (hereinafter referred to as a “constricted portion”) having a width dimension smaller than the design value is generated. 5 and 6, (a) shows the wiring pattern 1b of the design value, and (b) shows the case where the surplus portion 1c is generated and the case where the constricted portion 1d is generated.

  Here, it is known that the surplus portion 1c is likely to occur inside the bent portion of the wiring pattern 1b. The surplus portion 1c and the constricted portion 1d also often have no problem in handling as a non-defective product, as in the case of thickening or thinning. In addition, when foreign matter is attached to the wiring pattern 1b, if the threshold value when binarizing the grayscale image is set appropriately, the foreign matter in the binarized image is the same pixel as the base 1a. As a value, it can be separated from the wiring pattern 1b. This type of foreign material includes a metal thin film that has been peeled off when the wiring pattern 1b is trimmed with laser light. If this type of foreign material adheres to the wiring pattern 1b, it causes a contact failure when mounting a semiconductor element. Therefore, when this kind of foreign matter exists, it is handled as a defective product.

  As described above, when the wiring pattern 1b deviates from the design shape, there are cases where it can be regarded as a non-defective product and a defective product. Therefore, the expansion processing and the contraction processing are alternatively performed in the region adjustment means 22 so as to reduce or increase the occupied area of the wiring pattern 1b obtained by binarizing the grayscale image by the separation means 21. Here, the area adjusting means 22 is a combination of the condition of whether to focus on the area of the base 1a or the area of the wiring pattern 1b and the condition of decreasing or increasing the occupied area of the wiring pattern 1b. Accordingly, it is selected whether to perform expansion processing or contraction processing.

  For example, when the area occupied by the wiring pattern 1b is reduced by paying attention to the base 1a, if the expansion process is performed, the region of the base 1a enters a part of the wiring pattern 1b at the boundary with the wiring pattern 1b. Thus, the area occupied by the region corresponding to the wiring pattern 1b is reduced. Further, when reducing the occupied area of the wiring pattern 1b by paying attention to the wiring pattern 1b, the shrinking process is performed to reduce the occupied area of the wiring pattern 1b. There are four types of combinations of whether the target of interest is the base 1a or the wiring pattern 1b, and whether the area of the wiring pattern 1b is reduced or increased. On the other hand, it is determined which of expansion processing and contraction processing is adopted. That is, (base, decrease) is expansion processing, (base, increase) is contraction processing, (wiring pattern, decrease) is contraction processing, and (wiring pattern, increase) is expansion processing.

  When the area adjustment means 22 reduces the area occupied by the wiring pattern 1b, if the degree of reduction is set appropriately, the wiring pattern 1b will not disappear or be divided in the narrowed or constricted portion 1d. The wiring pattern 1b is kept in a continuous state. That is, if the wiring pattern 1b has a narrowed or constricted portion 1d, the wiring pattern 1b can be processed even after the area adjustment means 22 reduces the area occupied by the wiring pattern 1b if the width dimension is within an allowable range. The continuity of is maintained.

  Similarly, when the area adjustment means 22 increases the occupied area of the wiring pattern 1b, if the degree of increase is set appropriately, the wiring pattern 1b does not continue in the fat portion or the surplus portion 1c. Are kept separate. In other words, if the wiring pattern 1b has a thickness or surplus portion 1c, the wiring pattern 1b can be processed even after the area adjustment means 22 increases the area occupied by the wiring pattern 1b if the width dimension is within an allowable range. The separability is maintained.

  After the area adjusting means 22 performs the expansion process or the contraction process on the boundary between the base 1a and the wiring pattern 1b, a plurality of connection areas that are candidates for the wiring pattern 1b are formed. Here, the connected region includes pixels having the same pixel value as the target pixel in the vicinity of the target pixel (eight pixels excluding the target pixel in the 3 × 3 pixel local region centered on the target pixel). Means a group of pixels composed of pixels of the same pixel value generated by repeating the procedure of setting the pixel as the next pixel of interest. If the degree of deformation from the design shape occurring in the wiring pattern 1b is within an allowable range, the number of wiring patterns 1b does not change even after the expansion process or the contraction process. In order to count the number of regions, the labeling means 23 gives a label to each connected region. The labeling means 23 counts the number of labels (number of labels) given to the connection area.

  Since the number of designed wiring patterns 1b is known, the comparison unit 24 determines whether or not the number of designed wiring patterns 1b matches the number of labels counted by the labeling unit 23. At this stage, if the number of labels is smaller than the number of designed wiring patterns 1b, it is determined that a short circuit has occurred in the wiring pattern 1b. If the number of labels is larger than the number of designed wiring patterns 1b, the wiring pattern 1b is divided. Is determined to have occurred. However, when the same number of divisions and short circuits occur in a part of the connection region, the number of the designed wiring patterns 1b matches the number of labels, so the number of the connection regions and the number of the designed wiring patterns 1b. Is a necessary condition, but not a sufficient condition.

  Therefore, when the number of connection regions matches the number of designed wiring patterns 1b, each connection region is regarded as a wiring pattern 1b, and the inspection unit 25 inspects each connection region for disconnection or short circuit. If the inspection means 25 determines that there is no disconnection and no short circuit in each connection area, each connection area is determined to be a wiring pattern 1b within an allowable range as a good product. That is, although the wiring pattern 1b is slightly deformed, the mounting substrate 1 that is within the non-defective range is not determined as a defective product, and as a result, the yield is improved.

  Further, as described above, if the wiring pattern 1b is deformed as a defective product, it can be reliably extracted by the comparison unit 24, and the quality determination is performed with high accuracy only for the good product candidates. Only the candidates need to be inspected with high accuracy, and as a result, the inspection time can be shortened as compared with the case in which high accuracy inspection is performed for all the candidates. That is, the inspection can be performed with high accuracy and in a short time.

  The processing procedure of the image processing unit 20 described above is collectively shown in FIG. FIG. 7 illustrates a case where the area corresponding to the wiring pattern 1b is contracted to reduce the area occupied by the wiring pattern 1b. First, the image processing unit 20 reads a grayscale image from the image memory 12 (S1) and binarizes it (S2). Next, a contraction process is performed on the pixels having the pixel value to be the wiring pattern 1b in the binarized image (S3). The degree of contraction is defined in advance as an acceptable range for good products. After the shrinking process, a labeling process for giving a label to each connected region is performed (S4), and the number of designed wiring patterns 1b is compared with the number of labels (S5). When the number of labels is larger than the design value, the candidate for the wiring pattern 1b is divided, so it is determined that the width dimension of the wiring pattern 1b is smaller than the allowable range or is disconnected (S6), and the number of labels If the number is smaller than the design value, a plurality of candidates for the wiring pattern 1b are continuous, so it is determined that the wiring pattern 1b is short-circuited (S7). Only when the number of labels coincides with the design value, a short circuit or disconnection is inspected for the candidate wiring pattern 1b (S8).

  The process of reducing the occupied area of the wiring pattern 1b as in the above-described process is mainly for the purpose of detecting disconnection or foreign matter, and a process of increasing the occupied area of the wiring pattern 1b is separately performed for short circuit detection. That is, in the operation shown in FIG. 7, the determination result of the short circuit in step S7 only indicates that the short circuit may be detected even if the occupied area of the wiring pattern 1b is reduced. Needs to increase the area occupied by the wiring pattern 1b.

  On the other hand, when disconnection or foreign matter is detected and attention is paid to a pixel having a pixel value that becomes the base 1a after binarization, expansion processing is performed instead of the contraction processing in step S3. After the expansion process, the labeling process and the comparison of the number of labels are performed in the same manner as in steps S4 and S5, and a determination of a short circuit or disconnection is performed in the same manner as in steps S6 and S7. However, when the number of labels matches the design value, the binarized image obtained in step S2 is masked by the region obtained by the expansion process, and the region other than the mask (that is, the wiring pattern) 1b candidates) are inspected for short circuits and disconnections.

  By the way, in the above-described configuration, an example in which a monochrome grayscale image output is used as the TV camera 11 as the imaging unit has been shown. However, when a color image output is used, the separation unit 21 performs color image output. The base 1a and the wiring pattern 1b are separated using the tristimulus values. That is, since the TV camera 11 outputs color signals having R, G, and B tristimulus values, it is suitable for separating the colors of the base 1a and the wiring pattern 1b from these three types of color signals. The two colors are selected and the difference between the two colors is binarized to separate the area of the base 1a and the area of the wiring pattern 1b.

  This will be described more specifically. Here, it is assumed that the base 1a is black and the surface of the wiring pattern 1b is gold-plated. In the case of such a combination, the separation unit 21 obtains a difference image made up of the difference between the color signals of R and B, and binarizes it using an appropriate threshold for this difference. In other words, an image made up of R color signals and an image made up of B color signals are generated, a difference image consisting of a difference in density value between pixels at the same position in both images is generated, and the difference image is binarized. To do. The threshold value used for binarization can be set fixedly or dynamically like the threshold value applied to the grayscale image.

  The difference between the color signals of R and B is obtained when the base 1a is black and the wiring pattern 1b is plated with gold, corresponding to the value corresponding to the base 1a and the wiring pattern 1b. This is because the difference from the value is maximized. For example, when the base 1a is green and the wiring pattern 1b is gold-plated, the difference is maximized when the color signal difference between R and G is obtained.

  Even when a color image is used, the process after binarization is the same as that for a grayscale image. That is, after the area adjusting means 22 performs the expansion process or the contraction process so as to reduce or increase the area occupied by the area corresponding to the wiring pattern 1b, the labeling means 23 gives a label to each connected area, and the comparison means 24 It is determined whether or not the number of labels matches the number of designed wiring patterns 1b. If they match, the judging means 25 inspects each connected region for disconnection or short circuit. By inspecting according to such a procedure, it is possible to determine whether the wiring pattern 1b is good or not, and if the narrowing or constricted portion is present in the wiring pattern 1b but is within the allowable range as a good product, it is treated as a good product. This improves the yield.

(A) is a block diagram which shows embodiment of this invention, (b) is a top view which shows the relationship between the mounting board | substrate and pallet in the same as the above. It is a top view which shows an example of the mounting board | substrate used for the same as the above. It is a figure explaining the attention area | region in the same as the above. It is a figure which shows an example of the binarized image in the same as the above. It is a figure which shows the principal part of the binarized image in the same as the above. It is a figure which shows the principal part of the binarized image in the same as the above. It is operation | movement explanatory drawing which shows the process sequence of the image process part used for the same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mounting board 1a Base 1b Wiring pattern 11 Imaging means 20 Image processing part 21 Separation means 22 Area adjustment means 23 Labeling means 24 Comparison means 25 Inspection means Dm Region of interest

Claims (4)

  An image of the mounting board on which the wiring pattern is formed on the surface of the base made of an insulating material is picked up by the image pickup means, and the wiring pattern and the base are separated using the pixel value for the region of interest in the image obtained by the image pickup means. Then, after applying one of expansion processing and contraction processing to the boundary between the wiring pattern and the base in the region of interest, the number of connected regions that are wiring pattern candidates is counted, and the wiring designed by the number of candidates counted A method for inspecting a wiring pattern, comprising: inspecting the quality of a wiring pattern in a connected region that is a candidate for a wiring pattern when the number of patterns matches.   The image obtained by the imaging means is a grayscale image, and the wiring pattern and the base are separated by binarizing the grayscale image using a threshold value set for the density value of the grayscale image. The wiring pattern inspection method according to claim 1.   The image obtained by the imaging means is a color image, and the difference between the value corresponding to the wiring pattern and the value corresponding to the base among the two differences of the tristimulus values of the color image is maximized. The wiring pattern inspection method according to claim 1, wherein the wiring pattern and the base are separated by binarizing the difference.   An image pickup means for picking up an image of a mounting board in which a wiring pattern is formed on the surface of a base made of an insulating material, and a wiring pattern and the base are separated using a pixel value for a region of interest in the image obtained by the image pickup means. Separating means that performs expansion processing and contraction processing alternatively on the boundary between the wiring pattern and the base in the region of interest, and a connection region that is a candidate for the wiring pattern after the expansion processing or contraction processing And labeling means for assigning labels to each connected area and counting the number of labels applied thereto, and when the number of labels matches the number of designed wiring patterns, the wiring pattern within the connected area that is a candidate for the wiring pattern A wiring pattern inspection apparatus comprising: an inspection means for inspecting pass / fail.

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