JP2010008149A - Inspection region setting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection region setting method which enables extensive and collective setting of the inspection region of solders and foreign matters in a multi-electrode IC mounting part by foreign matter inspecting small regions and which is capable of easily performing the setting of the inspection region to an inspection region having specific color data. <P>SOLUTION: The inspection region 20 as a whole is set to so as to set the foreign matter inspecting small regions 24 for inspecting the foreign matters to divide the whole region of the inspection region 20 by the foreign matter inspecting small regions 24. The foreign matter inspecting region is set, by removing a land-inspecting regions 9 from the divided regions and the color data of a specific region is acquired, with respect to the foreign matter inspecting region to acquire the position coordinates of the region which coincides with those of the color data of the specific region from taken image data. A specific region inspecting region is again set to a detected region and the foreign matter inspecting small regions are reset at the periphery of the specific region inspecting region to perform region setting, with respect to the inspection region as a whole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for setting an inspection area of a substrate used in an electronic device or the like, and more particularly, a method for setting an inspection area in a mounting portion when a component having a plurality of electrodes is mounted on one IC (integrated circuit). It is about.

  In electronic component mounting, small and inexpensive components such as chip-type resistors and capacitors are surface-mounted, but along with the high performance and miniaturization of electronic devices, the substrate size is also required to be reduced. Depending on the number of parts on the surface, it becomes impossible to arrange a power source or a ground on the surface. As a result, the number of layers of the substrate has increased, and the layers are connected by through holes.

  In addition, in order to demand small size and high functionality, ICs dedicated to the required electronic devices, especially BGA (Ball Grid Array) and CSP (Chip Scale Package), have been developed, and the efficiency of function and area is achieved by mounting one dedicated IC. It is planned.

  As shown in FIG. 19, these mounting steps are constituted by a solder printing 90, a chip mounter 91, a multi-function device 92, and a reflow furnace 93, and the product unit price increases with each step. In particular, in the mounting in the multi-function device 92, the component unit price is also expensive, and when an abnormality occurs due to mounting, the amount of loss before and after the multi-function device 92 becomes several tens of times.

  In addition, after the chip 4 is mounted on the printed circuit board 1 by the chip mounter 91, if there is a chip in the IC mounting portion, both the IC 5 and the printed circuit board 1 are damaged. In some cases, a solder printing state and a foreign matter inspection for preventing the bite of the chip into the BGA or CSP are introduced between the chip mounter 91 and the multi-function device 92.

  However, in order to inspect foreign matter outside the land of the substrate in a multi-electrode part such as BGA or CSP, inspections other than each land part are performed. Generally, Gerber data is used for land inspection, and color determination inspection based on the teaching of solder color is sometimes used. However, when performing foreign object inspection in the same process, since the foreign object is unspecified, If there is no substrate color information in the inspection area, it is determined that there is a foreign object.

Patent Document 1 discloses an inspection region setting method in a CSP having multiple electrodes. By preparing one inspection region and inputting the number of pads, the inspection region over the entire CSP mounting surface is collectively displayed. The method of setting is described.
JP-A-11-307595

  In recent years, in order to increase the efficiency of component placement within the board area, the BGA electrodes are not arranged at the same pitch, and the pitch of the lands 6 of the board 7 is not equal to the equally spaced portion A as shown in FIG. An interval portion B exists. As a result, in addition to the pattern, through holes 8 are arranged on the BGA mounting surface as shown in FIG. 21, and it is necessary to set a plurality of pieces of color information as background colors. In the setting, an overlapping area occurs due to the overlap with the land inspection area and the surrounding foreign object inspection area. Considering these, it takes an enormous amount of time when the operator sets the optimum region and background color condition.

  In the method described in Patent Document 1, it is possible to deal with regions corresponding to equally-spaced portions. However, as shown in FIG. At the same time, it is impossible to set the foreign matter between lands.

  An object of the present invention is to solve the above-described conventional problems and to easily set an inspection area to an inspection area having a plurality of types of areas for solder and foreign matter inspection areas in a mounting portion of a multi-electrode component. It is to provide an inspection area setting method.

In order to achieve the object, the invention according to claim 1 divides the entire inspection region into inspection small regions, removes a region including a specific region from the divided inspection small region, and color information of the specific region The inspection subregion around the specific part is reset according to a threshold value based on the color information of the other part and the part other than the color information. The inspection area setting method according to claim 2, When the area is set, the inspection small area is set based on the size of the foreign object to be detected.

  The invention according to claim 3 is the inspection region setting method according to claim 1 or 2, wherein the inspection small region around the specific part is overlapped with respect to the inspection small region set in duplicate. The inspection small area set as described above is deleted, invalidated, or reduced based on the start / end coordinates.

  According to a fourth aspect of the present invention, in the inspection region setting method according to any one of the first to third aspects, in the resetting of the inspection small region, the reset small inspection region is a solder inspection region of the inspection region and When overlapping with a specific part, the inspection area is reduced based on the direction in which the solder inspection area is arranged with respect to the reset inspection small area.

  According to a fifth aspect of the present invention, in the inspection area setting method according to any one of the first to fourth aspects, in the threshold setting when the inspection small area is reduced, a detection ratio threshold or a detection ratio is set according to the reduction ratio. The reference area value to be derived is changed.

  The invention according to claim 6 is the inspection region setting method according to any one of claims 1 to 5, wherein the specific part is a through hole.

  According to the present invention, it is possible to easily set a printing and foreign matter inspection area such as a BGA mounting portion in a short time, and color background conditions that need to be individually set can be easily set in all inspection areas. can do. Moreover, even for small inspection areas that need to be set in a complicated manner, the number of inspection areas and the area size are optimized by dynamic relocation, leading to a reduction in teaching time and further inspection by optimal arrangement of inspection areas. Time can be shortened.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
A first embodiment for explaining an inspection region setting method according to the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a basic configuration of the present embodiment, FIG. 2 is a flowchart relating to inspection area setting in the present embodiment, and FIG. 3 is a schematic diagram of a substrate surface on which a BGA is mounted on a printed circuit board in the present embodiment. FIG.

  In FIG. 1, 1 is a printed circuit board, 2 is solder, 3 is an imaging unit that images the printed circuit board 1, 5 is an illumination unit that illuminates the printed circuit board 1, and 10 is an image storage unit that stores an image from the imaging unit 3. 11 is a color extraction unit that extracts colors from the image stored in the image storage unit 10, 12 is a region setting unit that sets a region based on the result of the color extraction unit 11, and 13 is a specific region based on the setting in the region setting unit 13. In FIG. 3, 6 is a land, 7 is a printed circuit board, 8 is a through hole, and 20 is an entire inspection area.

  In FIG. 1 to FIG. 3, when the processing related to the inspection area setting is started, data to be a land area is read from the data input means 14 into the arithmetic processing section 15 in step S1. The data used here is generally Gerber data indicating the coordinates of the mask when performing solder printing. Next, in step S <b> 2, the target BGA mounting portion is set as the entire inspection area 20 based on the read land area data.

  Next, in step S3, as shown in FIG. 4, a foreign substance inspection small area 24 for detecting foreign substances is set. The size of the foreign substance inspection subregion 24 needs to be obtained from the size of the target foreign substance to be detected, and examples of obtaining this are shown in FIGS. FIG. 5 schematically shows the inspection area width 31 and the inspection area height 32 of the foreign object inspection small area 23 including the foreign object 30.

  Here, the foreign material 30 is assumed to be circular, and the inspection area width 31 is W, the inspection area height 32 is H, and W = H. In this case, since the area of the foreign matter 30 is W / 2 * W / 2 * π and the area of the foreign matter inspection subregion 23 is W * W, the ratio of the foreign matter 30 to the foreign matter inspection subregion 23 is (W / 2 * W / 2 * π) / W * W * 100 [%]. If W = 2, it is 78.5%.

  Therefore, in this case, detection can be made by setting the ratio of the foreign substance inspection small area 23 to (W / 2 * W / 2 * π) / W * W * 100 [%], but as shown in FIG. When the foreign substance 30 exists in the center of the four foreign substance inspection subareas 23, this ratio becomes the lowest in each foreign substance inspection subarea 23, and {(W / 2 * W / 2 * π) / 4} / W * W * 100 [%]. If W = 2, it is 19.625%, and there is only an area that is less than 1/5 of the foreign matter inspection subregion 23. In this case, all of the foreign object shapes can be detected, and in actual imaging, there are color shading changes and the like, and actual stable determination cannot be performed.

  Therefore, the foreign matter inspection small region 24 is set to a size equal to or less than ¼ of the rectangular shape including the foreign matter 30 to be detected, and is arranged with respect to the entire inspection region 20, so that all the foreign matter inspection small regions 24 are set. In the area 24, detection is possible at a ratio of {(W / 2 * W / 2 * π) / 4} / W / 2 * W / 2 * 100 [%] or more.

  As described above, in step S4, the foreign substance inspection small area 24 is set over the entire inspection area 20.

  In step S5, a portion overlapping the land inspection area 9 is deleted, invalidated, or reduced with respect to the foreign substance inspection small area 24 set in the entire inspection area 20 (the entire surface of the printed circuit board 1). The foreign substance inspection small area 24 existing within the start / end point range of the land inspection area 9 is deleted or invalidated so that the foreign substance inspection is not performed. Similarly, when a part exists in the start and end points, it may be deleted or invalidated. Since the area of the size to be detected is set to ¼ or less and the length is set to ½ or less, the foreign substance inspection small area 24 is deleted or invalid if it is not included in the land inspection area 9. Even if it is a case, since there is an adjacent foreign substance inspection subregion 24, there is no influence in detecting a foreign substance.

  In step S6, in the configuration as shown in FIG. 1, the printed circuit board 1 that is actually to be inspected is irradiated by the illumination unit 5, imaged by the imaging unit 3, and image information is stored in the image storage unit 10.

  From the image information stored in the image storage means 10 in step S7, the color information of the land color information for inspecting the unpainted solder shown in FIG. 7 and the substrate color information 201 as the background color for detecting foreign matter is obtained. Do. Also, in order to distinguish and set the background color from the substrate color that is arranged on the entire surface of the substrate when performing foreign object inspection at this time, a portion such as the through hole 8 that is different from the land color information and the substrate color information 201 is specified. It is necessary to obtain the location color information 202.

  This is because if the specific location color information 202 other than the substrate color information 201 as the background color is not set as appropriate, it becomes uniform as shown in FIG. 8 and cannot be extracted at all.

  However, in FIG. 7, the specific color information 202 is provided in the region 63, the region 64, the region 65, and the region 66 with the through hole 8, and the substrate color information is provided in the region 67, the region 68, the region 69, and the region 70 without the through hole 8. When 201 is set, the extraction area 60 can be extracted as shown in FIG.

  The extraction area 60 is a hatched portion shown in FIG. 9, and in each foreign substance inspection small area, assuming that the inspection area width 61 is X, the inspection area height 62 is Y, and X = Y is a rectangular area X The area of 60 is X * X * π / 4. When the extraction is performed only with the substrate color information 201, the extraction can be performed only at a ratio of about 21% in the rectangular area (the entire foreign substance inspection small area in FIG. 9), but the specific location color information 202 is set in a portion where the specific location exists. In addition, by setting the substrate color information 201 in the other part, it is possible to narrow down to the foreign substance inspection small area around the extraction area 60, and the ratio of the extraction area 60 can be detected at about 78.5%. It becomes.

  Next, in step S8, the printed circuit board 1 to be actually inspected is irradiated by the illumination unit 5, and imaged by the imaging unit 3, and image information is stored in the image storage means 10, or acquired in step S6. Image information stored in the image storage means 10 is read out.

  In step S9, a portion where the specific location color information 202 exists is detected based on the image information acquired in step S8.

  As the detection method, an area having the same color information as the specific location color information 202 is extracted from the foreign substance inspection small region 24 and set to have the through holes 8 at a certain ratio or more. When it is assumed that the size of the through hole 8 is the same size as the foreign matter inspection small region 24, it is set to detect the foreign matter more than 1/6 of the area of the foreign matter inspection small region 24. The through hole 8 can be detected regardless of the positional relationship of the holes 8. As shown in FIG. 10, even though the through hole 8 is the same size as the foreign substance inspection small region 24 and exists over four regions, the through hole 8 is about 19% in each foreign particle inspection small region 24. Will exist.

  However, normally, as shown in FIG. 10, since the position of the through hole 34 cannot exist at a position equally divided with respect to the foreign matter inspection small region 24, the region detected by the foreign matter inspection small region 24 is the region 35. , The entire region of the through hole 34 cannot be detected as in the region 36.

  Therefore, in step S10, based on the region where the through hole 8 exists, an inspection region 37 for detecting the actual center of gravity of the through hole 34 is set as shown in FIG. The inspection area 37 can include the through hole 34 by setting an area twice as large as the foreign substance inspection small area 24 detected in step S9.

  In step S11, the circular shape of the through hole 34 is detected, and the center of gravity 38 and the through hole diameter 39 are obtained.

  In step S12, as shown in FIG. 12, a foreign substance inspection small region 80 in the through-hole portion is set with a through-hole diameter 39 at the center of gravity 38 obtained in step S11. At this time, it is possible to set the specific part color information 202 as the background color for the foreign substance inspection small area 80.

  In step S13, as shown in FIG. 13, by setting the foreign substance inspection small area 80, the non-foreign substance inspection small area 81 that is set to overlap with the foreign substance inspection small area 80 is the same area. In order to prevent double inspection and inspection under different conditions of the background color, deletion or invalidation setting is performed.

  In this state, there is an uninspected area around the through hole 34. Therefore, in step S14, the foreign substance inspection small area 82 is rearranged near the periphery of the through hole 34 as shown in FIG.

  Here, in step S15, the foreign substance inspection small area is optimized. In the case of FIG. 14, there are overlapping portions in the vicinity of the through hole 34 and in the foreign substance inspection small area 24 set in step S4. However, since there is no area completely included in each area, the foreign substance is not changed without changing the area. Perform an inspection. The overlap check is performed by starting the foreign matter inspection subregion 24 ≦ the starting point of the foreign matter inspection subregion 82, the end point of the foreign matter inspection subregion 82 ≦ the end point of the foreign matter inspection subregion 24, or the starting point of the foreign matter inspection subregion 82 ≦ foreign matter inspection subregion. The start point of 24, the end point of the foreign substance inspection small area 82 ≤ the end point of the foreign substance inspection small area 82, and the included area is deleted or invalidated. The same applies to the completely same area, and either area is deleted or invalidated.

  As shown in FIG. 17, when there is an overlapped foreign substance inspection small area 86 and an overlapped foreign substance inspection small area 87, as shown in FIG. By invalidating or deleting the inspection area, it is possible to secure the inspection area without damaging the entire foreign substance inspection small area.

  In step S16, as shown in FIG. 15, when another through hole exists in the vicinity and the rearranged foreign substance inspection small region 82 overlaps the through hole 83, the inspection is performed according to the relative positional relationship of the through holes. Reduce the area.

  When the through hole 83 is in the + Y direction with respect to the through hole 84 as shown in FIG. 15, the Y width of the foreign substance inspection small area 82 is the same as the Y lower end coordinate of the foreign substance inspection small area 80 as shown in FIG. Use coordinates.

  However, in the case of FIG. 16, the through hole 83 is also in the + X direction with respect to the through hole 84. In this case, the Y width of the foreign substance inspection small area 82 is the same coordinate as the X right end coordinate of the foreign substance inspection small area 80. It is good.

  In step S17, when the foreign substance inspection small area is rearranged, there may be a land around it. In this case as well, the foreign substance inspection small area is overlapped with the through hole shown in FIGS. The inspection area is optimized by reducing the size.

  As a foreign object inspection, set up a foreign substance inspection small area, set a background color inside it, extract a color part different from the background color, and detect the presence of foreign substances at a ratio of the extracted value to the foreign substance inspection small area To do. However, when the foreign substance inspection small area is reduced as in steps S16 and S17, the area of the reference foreign substance inspection small area changes, and the ratio when the foreign substance exists changes. It will change. Although it is possible to cope with this by setting the threshold value and the reference area value individually for all the inspection areas, as shown in FIG. Management becomes complicated.

  For such a case, the detection ratio threshold or the reference area value from which the detection ratio is derived is changed according to the reduction ratio.

  For example, the width of the foreign object detection small area is set to X, the height is set to Y, and the detection threshold in the foreign object detection small area is set to 50% of the reference area. In this case, it is possible to detect the presence of foreign matter when the foreign matter is present in an area of 1/2 * X * Y or more, but the height is 3/4 because the foreign matter detection sub-regions overlap. In this case, the reference area is X * 3/4 * Y.

  Therefore, the detection ratio of one region is varied in accordance with the reduction ratio 3/4.

  The reference area value remains X * Y, and the detection ratio of that region is 50% * 3/4 = 3/8. In this case, the inspection can be performed on the same basis as other foreign object detection small areas.

  The other areas are inspected with the reference area value reduced and the detection ratio is kept as it is.

  In this case, since the detection ratio is the same as the other area inspection ratio, the detection sensitivity can be changed uniformly when the detection sensitivity is changed.

  As for this method, the detection sensitivity of foreign matters remains maintained regardless of which method is selected.

  In the mounting process of an electronic component having a multi-electrode, the present invention can set the non-uniform inspection area of the mounted portion of the multi-electrode IC in a short time. Useful for early verification of time.

The block diagram which shows the basic composition of embodiment of the inspection area | region setting method which concerns on Embodiment 1 of this invention. Flowchart relating to inspection area setting in the first embodiment Explanatory drawing which shows the board | substrate surface which mounts BGA on the printed circuit board in Embodiment 1 schematically Explanatory drawing when a foreign substance inspection small area is set for an inspection area in the first embodiment Explanatory drawing of the foreign substance inspection small area in Embodiment 1 Explanatory drawing regarding the size of the foreign substance inspection small region of the first embodiment Explanatory drawing which shows the detection method by the color of a through hole and a foreign material in Embodiment 1. Explanatory drawing when inspecting by the method shown in FIG. 7 in the first embodiment Explanatory drawing when a foreign object is extracted in the first embodiment Explanatory drawing of the foreign substance inspection small area which detected the through hole and the through hole in Embodiment 1 Explanatory drawing of the inspection area for through holes and through holes in the first embodiment Explanatory drawing of the foreign substance inspection small area for through-holes calculated | required from the through-hole shape extracted in FIG. 11 in Embodiment 1 Explanatory drawing of the foreign substance inspection small area deleted in duplicate with the through hole in the first embodiment Explanatory drawing when a foreign substance inspection small region is set in the vicinity of the through hole in the first embodiment Explanatory drawing of the overlapped foreign substance inspection small area in the first embodiment Explanatory drawing when the foreign substance inspection small area is reduced in the first embodiment Explanatory drawing of the some overlap foreign substance inspection small area in Embodiment 1 Explanatory drawing of the area | region which actually invalidates or deletes from the overlapping foreign material inspection small area in Embodiment 1 Explanatory drawing which shows the structure of the conventional BGA mounting process Explanatory drawing about arrangement of printed circuit board and land of conventional example Explanatory drawing about arrangement of printed circuit board, land and through hole of conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Solder 3 Imaging part 6 Land 5 Illumination part 7 Printed circuit board 8,83,84 Through hole 9 Land inspection area 10 Image storage means 11 Color extraction means 12 Area setting means 13 Detection means 14 Data input means 15 Operation processing part 20 Whole inspection area 23, 24, 80, 82 Foreign object inspection small area 30 Foreign object 31, 61 Inspection area width 32, 62 Inspection area height 33 Foreign object 34 Through hole 35, 36 area 37 Inspection area 38 Center of gravity 39 Through hole diameter 60 Extraction Area 63 to 70 Area 86 to 88 Sub-foreign particle inspection small area 201 Substrate color information 202 Specific location color information

Claims (6)

Divide the entire inspection area into inspection small areas,
Removing the region including the specific part from the divided examination subregion,
An inspection region setting method comprising: resetting the inspection small region around the specific region based on a threshold value based on the color information of the specific region and the color information of other regions.   2. The inspection area setting method according to claim 1, wherein when setting the inspection small area, the inspection small area is set based on a size of a foreign object to be detected.   In the resetting of the examination subregion around the specific part, the examination subregion set redundantly is deleted or invalidated based on the start / end coordinates for the examination subregion set redundantly. Alternatively, the inspection area setting method according to claim 1 or 2, wherein the reduction is performed.   In the resetting of the inspection small area, when the reset inspection small area overlaps the solder inspection area and the specific part of the inspection area, the solder inspection area 4. The inspection area setting method according to claim 1, wherein the inspection area is reduced based on a direction in which the inspection area is arranged.   The inspection area setting according to any one of claims 1 to 4, wherein in the threshold setting when the inspection small area is reduced, a detection ratio threshold or a reference area value for deriving the detection ratio is changed according to the reduction ratio. Method.   6. The inspection region setting method according to claim 1, wherein the specific part is a through hole.

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