JP2009002796A - Inspection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection apparatus that precisely inspects the flaw having a three-dimensional shape produced on the surface of an article. <P>SOLUTION: The image due to the light reflected by irradiating a CSP tape with light from oblique is photographed in a first scanning stage 52 and the image due to the light reflected by irradiating the CSP tape with light from above is photographed in a second scanning stage 66. A computer 82 extracts the region markedly low in density level in the image acquired in the first scanning stage 52 and extracts a region markedly high in density level in the image acquired in the second scanning stage 66 to determine that the respective extracted regions are pits if the respective regions are almost at the same position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an inspection apparatus, and more particularly to an inspection apparatus that inspects a defect having a three-dimensional shape generated on the surface of an article.

  Conventionally, in the manufacture of a chip size package (hereinafter referred to as CSP) in which the outer dimensions of a semiconductor device are reduced to the outer dimensions of a semiconductor element, a plurality of patterns formed corresponding to one chip are repeatedly formed. A method of manufacturing a large number of packages at once using a tanned tape (hereinafter referred to as CSP tape) has been proposed.

  In this CSP tape, a conductive film such as a copper foil is formed on the surface of a base material such as a polyimide base material by vapor deposition or the like, and then a CSP wiring, an electrode, a beam lead, a through hole, etc. are used by using a normal etching technique. It is a long tape patterned by repeating a plurality of patterns.

  As for the inspection of the quality of the metal pattern formed on such a CSP tape, as described in Patent Document 1, for example, a light beam beam is irradiated from below the CSP tape and the transmitted light is imaged with a camera. Techniques for inspection have been proposed.

As for detection of dust adhering to the CSP tape portion and defects in the resist pattern portion, for example, as described in Patent Document 2, a light beam is irradiated from above the CSP tape and the reflected light is imaged with a camera. A technique for detecting this is proposed.
JP 2004-212159 A JP 2006-105816 A

  However, a technique for inspecting a defect of a three-dimensional shape such as a pit generated in a metal pattern formed on a tape-like substrate such as the CSP tape has not been established. In some cases, the defect could not be inspected.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an inspection apparatus capable of accurately inspecting a three-dimensional shape defect generated on the surface of an article.

  In order to achieve the above object, the invention of claim 1 is reflected by the inspection object by irradiating the inspection object with light from different directions and by the irradiation means. An imaging unit that captures each image by each light, and a detection unit that detects a three-dimensional shape defect from each image captured by the imaging unit.

  The irradiation means is an oblique direction irradiation means comprising at least one of a first irradiation means for irradiating light to the inspection object from the first oblique direction and a second irradiation means for irradiating light to the inspection object from the second oblique direction. And third irradiating means for irradiating the inspection object with light from above at a timing different from that of the oblique direction irradiating means.

  By irradiating the oblique direction irradiating means and the third irradiating means at different timings, the image by the light reflected by the inspection object by being irradiated by the oblique direction irradiating means and the third irradiating means are irradiated. By doing so, it is possible to separate the image from the light reflected by the inspection object.

  In this case, the detection means has a density level outside the first predetermined range in the image captured by the imaging means when light is irradiated by the oblique direction irradiation means, and the light is irradiated by the upward direction irradiation means. In some cases, an area having a density level outside the second predetermined range is extracted from the image captured by the imaging means, and a defect having a three-dimensional shape is detected based on each extracted area.

  Here, the first predetermined range is a range of density levels in a region where a three-dimensional shape defect does not occur in an image captured when light is irradiated by the oblique direction irradiation unit. The second predetermined range is a range of density levels in a region where a three-dimensional shape defect does not occur in an image captured when light is irradiated by the third irradiation unit.

  The optical path of the light reflected by the inspection object differs depending on the three-dimensional shape of the inspection object. For this reason, when a defect having a three-dimensional shape is generated in the inspection target, the three-dimensional defect region has a density level different from that of the other region in the captured image. As a result, by extracting a region outside the density level range of the region where the density level is not generated in the captured image, the three-dimensional shape defect can be detected.

  Further, when a defect having a three-dimensional shape occurs in the inspection target, the density level in the captured image varies depending on the direction in which the inspection target is irradiated with light. Accordingly, the accuracy of detection of a defect having a three-dimensional shape is extracted by extracting a region having a density level outside a predetermined range from each image by each light reflected from the inspection object by being irradiated from a plurality of different directions. Can be better.

  For example, when a region whose density level is outside the first predetermined range is extracted from an image captured by the imaging unit when light is irradiated by the oblique direction irradiation unit, and when the light is irradiated by the upward direction irradiation unit An area having a density level outside the second predetermined range is extracted from the image picked up by the image pickup means, and when the extracted areas are substantially at the same position, it is determined that the area is a defect area having a three-dimensional shape. May be.

  Moreover, it is good to further provide the 4th irradiation means which irradiates light to a test object from the downward direction at the same timing as a 3rd irradiation means.

  The plurality of irradiation means may irradiate light of different colors. In this case, each image can be separated by color.

  The detection unit extracts a region having a density level outside a predetermined range from each image captured by the image capturing unit, and detects a three-dimensional shape defect based on at least one of the positional relationship and the shape of each extracted region. .

  Here, the predetermined range is a range of density levels in a region where a three-dimensional shape defect does not occur in an image captured when light is irradiated by the irradiation unit.

  For example, while extracting the area | region where a density level is outside a predetermined range in the image imaged when light was irradiated by the irradiation means which irradiates light from one side of a test object, light is irradiated from the other side of a test object Whether a defect having a three-dimensional shape is generated by extracting a region having a density level outside a predetermined range in an image captured when light is irradiated by the irradiation unit and obtaining a distance between the extracted regions. It may be determined whether or not. Further, it may be determined whether or not a defect having a three-dimensional shape has occurred based on the feature of the shape of the extracted region.

  As described above, according to the present invention, it is possible to obtain an effect that a three-dimensional shape defect generated on the surface of an article can be inspected with high accuracy.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
As shown in FIG. 1, the inspection apparatus 10 according to the first embodiment includes a tape supply unit 12, a winding unit 14, and the like, and a CSP tape 16 that is supplied and conveyed by the tape supply unit 12. And the winding unit 14 is made to take up.
(Tape supply unit)
The tape supply unit 12 includes a reel-side reel shaft 22 and a CSP tape 16 that hold a CSP roll 20 formed by winding a CSP tape 16 and a spacer tape 18 on which a large number of package patterns are repeatedly formed. An unwinding-side spacer shaft 24 that winds and holds the pulled-out spacer tape 18 is provided.

  A guide 26 for changing the transport direction of the CSP tape 16 is disposed on the delivery side of the CSP roll 20.

In the CSP tape 16 of this embodiment, a metal pattern such as a copper foil is formed by etching on the surface of a synthetic resin base tape that transmits light, and an insulating resist pattern is further formed thereon. It is what.
(Winding unit)
The winding unit 14 includes a winding-side spacer shaft 28 that holds the spacer tape 18 formed in a roll shape, and a winding-side reel shaft 30 that winds the spacer tape 18 and the inspected CSP tape 16 together. Yes.

  A guide 32 for changing the transport direction of the CSP tape 16 is disposed on the tape winding side of the winding side reel shaft 30.

  Between the tape supply unit 12 and the winding unit 14, a short dancer 34, a first feed roller 36, a second feed roller 38, a long dancer 40, guides 42 and 44 that form a transport path for the CSP tape 16. , 46, 48 and short dancer 50 are arranged in this order.

In addition, the first feed roller 36 and the second feed roller 38 are horizontally arranged with a space therebetween, and the first feed roller 36 and the second feed roller 38 have a first feed roller 36 and a second feed roller 38. A scan stage 52 and a second scan stage 66 are provided.
(First scan stage)
As shown in FIG. 2, a table 54 is disposed on the first scan stage 52. Air is ejected from the table 54 toward the CSP tape 16, and a thin air layer is formed between the CSP tape 16 and the table 54.

  Each presser roller 56 is a driven roller that freely rotates, and abuts on the upper surface of the CSP tape 16 to limit the upward movement of the CSP tape 16.

  Note that air is also ejected from the guide 26, the short dancer 34, the long dancer 40, the guides 42, 44, 46, 48, and the short dancer 50 toward the CSP tape 16, and between the CSP tape 16 and each member. A thin air layer is formed.

  As shown in FIG. 2, an image reading unit including a lens 58 and a CCD line sensor 60 serving as an imaging unit is disposed directly above the center of the table 54 in the conveyance direction of the CSP tape 16. In the CCD line sensor 60, pixels are arranged in the width direction of the CSP tape 16 (front and back direction in FIG. 2).

  In addition, a first irradiation device (line light source) 62 that is a first irradiation unit that irradiates an optical path L1 indicated by a one-dot chain line below the CCD line sensor 60 is disposed on the upstream side in the conveyance direction of the CSP tape 16. A second irradiation device (line light source) 64 that is a second irradiation unit for irradiating the lower part of the CSP tape 16 in the transport direction with a light path L2 indicated by a one-dot chain line below the CCD line sensor 60 is disposed.

  The first irradiation device 62 and the second irradiation device 64 have a plurality of LEDs (not shown) arranged along the width direction of the CSP tape 16 and direct the light beam emitted from the LEDs toward the CSP tape 16. And a light guide plate (not shown) that irradiates in a line shape. Here, the LED of the first irradiation device 62 and the LED of the second irradiation device 64 emit light beams of the same color.

  Further, each light beam is irradiated toward one point when viewed from the side in the tape transport direction. As a result, the respective light beams are superimposed on the surface (upper surface) of the CSP tape 16 and irradiated in a line shape in the tape width direction.

  The CSP tape 16 is wound around each feed roller 56, and is fed at a constant speed in one direction as each feed roller 56 rotates. When the CSP tape 16 passes over the table 54, the image reading unit performs the CSP tape. Sixteen surfaces are imaged.

  Next, an image captured by the first scan stage 52 will be described.

  With reference to FIG. 3, the reflected light which is irradiated by the first irradiation device 62 and the second irradiation device 64 and reflected by the CSP tape 16 will be described. In the CSP tape 16 shown in FIGS. 3A and 3C, pits which are three-dimensional shape defects are generated. As shown in FIGS. 3A and 3C, in this embodiment, a V-shaped pit will be described as an example, but the shape of the pit inspected by the inspection apparatus 10 is V-shaped. Not limited to.

  FIG. 3A shows the optical path of the light beam irradiated from the upstream side in the transport direction of the CSP tape 16 by the first irradiation device 62 and reflected by the CSP tape 16.

  An arrow A1 indicates an optical path when the light beam irradiated by the first irradiation device 62 is reflected in a region where no pit is generated. As indicated by the arrow A1, the reflected light reflected in the area where no pits are generated travels in an oblique direction with respect to the optical axis of the CCD line sensor 60, so that the amount of light incident on the CCD line sensor 60 is small.

  An arrow A2 indicates an optical path when the light beam irradiated by the first irradiation device 62 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow A2, the reflected light reflected by the slope region on the upstream side of the pit travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 60, so the amount of light incident on the CCD line sensor 60 is Few.

  An arrow A3 indicates an optical path when the light beam irradiated by the first irradiation device 62 is reflected by the slope region on the downstream side of the pit. As indicated by the arrow A3, the reflected light reflected by the slope region on the downstream side of the pit travels along the optical axis of the CCD line sensor 60, so that the amount of light incident on the CCD line sensor 60 is large.

  FIG. 3B shows an outline of a change in the amount of light beam irradiated by the first irradiation device 62, reflected by the CSP tape 16, and incident on the CCD line sensor 60. The horizontal axis indicates the position in the transport direction of the CSP tape 16, and the vertical axis indicates the amount of light. The amount of light when reflected by the upstream slope region is small, and the amount of light when reflected by the downstream slope region is large.

  Next, a case where the CSP tape 16 is irradiated from the downstream side in the transport direction of the CSP tape 16 by the second irradiation device 64 will be described.

  FIG. 3C shows the optical path of the light beam irradiated by the second irradiation device 64 and reflected by the CSP tape 16.

  An arrow A4 indicates an optical path when the light beam irradiated by the second irradiation device 64 is reflected in a region where no pit is generated. As indicated by the arrow A4, the reflected light reflected in the region where no pit is generated proceeds in an oblique direction with respect to the optical axis of the CCD line sensor 60, and therefore the amount of light incident on the CCD line sensor 60 is small.

  An arrow A5 indicates an optical path when the light beam irradiated by the second irradiation device 64 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow A5, the reflected light reflected by the slope region on the upstream side of the pit travels along the optical axis of the CCD line sensor 60, so that the amount of light incident on the CCD line sensor 60 is large.

  An arrow A6 indicates an optical path when the light beam irradiated by the second irradiation device 64 is reflected by the slope region on the downstream side of the pit. As indicated by the arrow A6, the reflected light reflected by the slope area on the downstream side of the pit travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 60. Therefore, the amount of light incident on the CCD line sensor 60 is Few.

  FIG. 3D shows an outline of the change in the amount of light beam irradiated by the second irradiation device 64, reflected by the CSP tape 16, and incident on the CCD line sensor 60. The horizontal axis indicates the position in the transport direction of the CSP tape 16, and the vertical axis indicates the amount of light. The amount of light when reflected by the upstream slope region is large, and the amount of light when reflected by the downstream slope region is small.

  The CCD line sensor 60 sends an image signal corresponding to the amount of incident light to a computer 82 (see FIG. 1) which is a detection means.

  The computer 82 takes in the image signal sent from the CCD line sensor 60, performs image processing, and inspects the CSP tape 16. As described above, the amount of the light beam irradiated by the first irradiation device 62 and reflected by the downstream slope region in the pit region and incident on the CCD line sensor 60 is large. Further, the amount of the light beam irradiated by the second irradiation device 64 and reflected by the upstream slope region in the pit region and incident on the CCD line sensor 60 is large. For this reason, when the light beam is irradiated from both the first irradiation device 62 and the second irradiation device 64, the CCD line sensor 60 is more in the region where the pit is generated than in the region where the pit is not generated. The amount of light beam incident on the beam increases. Therefore, the computer 82 extracts a region having a density level lower than a predetermined level in the image obtained by the first scan stage 52, and detects pits based on the extracted region.

  Further, the computer 82 can display the captured image of the CSP tape 16 on the monitor 84.

The first irradiation device and the second irradiation device are configured to be installed at opposite positions on the upstream side and the downstream side in the CSP tape transport direction with respect to the CCD line sensor. The irradiation device 2 may be installed at a position facing the CCD line sensor, for example, and may be installed at a position facing the CSP tape in the width direction.
(Second scan stage)
As shown in FIG. 4, a table 68 is arranged on the second scan stage 66. Air is ejected from the table 68 toward the CSP tape 16, and a thin air layer is formed between the CSP tape 16 and the table 68.

  Each presser roller 70 is a driven roller that freely rotates, and abuts on the upper surface of the CSP tape 16 to limit the upward movement of the CSP tape 16.

  As shown in FIG. 4, an image reading unit including a lens 72 and a CCD line sensor 74 is disposed immediately above the center of the table 68 in the conveyance direction of the CSP tape 16. In the CCD line sensor 74, pixels are arranged in the width direction of the CSP tape 16 (front and back direction in FIG. 4).

  Also, an epi-illumination unit that irradiates the CSP tape 16 with a light beam at a right angle is disposed above the table 68 and includes a third irradiation device (line light source) 76 and a half mirror 78 as third irradiation means. ing. Further, a transmitted light irradiation device (line light source) 80 for irradiating a light beam from the back surface of the CSP tape 16 is disposed in the table 68. The epi-illumination unit and transmitted light irradiation device 80 irradiates a light beam along the optical axis L3 of the CCD line sensor 74 indicated by a one-dot chain line.

  The third irradiation device 76 and the transmitted light irradiation device 80 irradiate a plurality of LEDs arranged along the width direction of the CSP tape 16 and a light beam emitted from the LEDs toward the CSP tape 16 in a line shape. It is comprised by the light-guide plate. Here, the LED of the third irradiation device 76 and the LED of the transmitted light irradiation device 80 emit light beams of the same color.

  The third irradiation device 76 and the transmitted light irradiation device 80 irradiate the light beam toward one point when viewed from the side in the tape transport direction. Thereby, the light beam is irradiated in a line shape in the width direction of the CSP tape 16 on the front surface (upper surface) of the CSP tape 16, and the back surface (lower surface) is opposite to the irradiation position of the light beam on the front surface (upper surface). The light beam is irradiated in a line shape in the width direction of the CSP tape 16.

  The CSP tape 16 is stretched over each feed roller 70, and is fed at a constant speed in one direction as each feed roller 70 rotates. Sixteen surfaces are imaged.

  Note that the light beam irradiated by the third irradiation device 76 is reflected by the metal pattern portion of the CSP tape 16 and transmitted through a portion other than the metal pattern portion (hereinafter referred to as a base portion). Further, the light beam irradiated by the transmitted light irradiation device 80 does not pass through the metal pattern portion of the CSP tape 16 but passes through the base portion. In this embodiment, for example, when the image density level is set to 0 (high density) to 250 (low density), the metal pattern portion has a density level near 200 and the base portion has a density level near 100. The irradiation by the third irradiation device 76 and the transmitted light irradiation device 80 is adjusted. Thereby, in the image obtained by the second scan stage 66, the metal pattern portion and the base portion can be distinguished. Further, as described above, when the irradiation by the third irradiation device 76 and the transmitted light irradiation device 80 is prepared, the pit region has a density level of around 50.

  The epi-illumination unit is composed of a third irradiation device and a half mirror, but is not limited to this as long as it can irradiate a light beam substantially along the optical axis of the CCD line sensor.

  Next, an image obtained by the second scan stage 66 will be described.

  With reference to FIG. 5, the reflected light that is irradiated by the third irradiation device 76 and reflected by the metal pattern portion of the CSP tape 16 will be described. Pits are generated in the metal pattern portion of the CSP tape 16 shown in FIG. As shown in FIG. 5A, in this embodiment, a V-shaped pit is described as an example, but the shape of the pit inspected by the inspection apparatus 10 is not limited to the V-shape.

  FIG. 5A shows an optical path of a light beam irradiated from above the CSP tape 16 by the third irradiation device 76 and reflected by the metal pattern portion of the CSP tape 16.

  An arrow A7 indicates an optical path when the light beam irradiated by the third irradiation device 76 is reflected in an area where no pit is generated. As indicated by the arrow A7, the reflected light reflected in the region where no pits are generated travels along the optical axis of the CCD line sensor 74, so that the amount of light incident on the CCD line sensor 74 is large.

  Arrows A8 and A9 indicate optical paths when the light beam irradiated by the third irradiation device 76 is reflected by the slope area of the pit. As indicated by the arrows A8 and A9, the reflected light reflected by the slope area of the pit travels in an oblique direction with respect to the optical axis of the CCD line sensor 60, so that the amount of light incident on the CCD line sensor 74 is small.

  FIG. 5B shows an outline of a change in the light amount of the light beam that is irradiated by the third irradiation device 76, reflected by the metal pattern portion of the CSP tape 16, and incident on the CCD line sensor 74. The horizontal axis indicates the position of the reflected CSP tape 16, and the vertical axis indicates the amount of light. It can be seen that the amount of light when reflected by a region other than the pit is large, and the amount of light when reflected by a region of the pit is small.

  The CCD line sensor 74 sends an image signal corresponding to the amount of incident light to the computer 82.

  The computer 82 takes in the image signal sent from the CCD line sensor 74, performs image processing, and inspects the CSP tape 16. As described above, when the light beam is irradiated from above the table 68, the amount of light incident on the CCD line sensor 60 when reflected at the pit region is reduced. Accordingly, the computer 82 extracts a region having a density level higher than a predetermined level in the image obtained by the second scan stage 66, and detects pits based on the extracted region.

  Next, with reference to FIG. 6, the characteristics of the image obtained by the first scan stage 52 and the second scan stage 66 will be described.

  6A and 6B show an example of an image of an area including pits. FIG. 6A is an example of an image obtained by the first scan stage 52. The light belt-shaped region TB indicates the base portion, the dark belt-shaped region TM indicates the metal pattern portion, and the region TP whose density level is significantly lower than the surroundings on the region TM indicates pits. FIG. 6B is an example of an image obtained by the second scan stage 66. A dark belt-like region TB indicates a pattern portion, a light belt-like region TM indicates a metal pattern portion, and a region TP whose density level is significantly higher than the surroundings on the region TM indicates pits.

  As described above, when pits are generated, a region whose density level is lower than the surroundings in the image obtained by the first scan stage 52 and a region where the density level is higher than the surroundings in the image obtained by the second scan stage 66. It is almost the same.

  On the other hand, FIGS. 6C and 6D show an example of an image of an area where dust or the like is attached.

  FIG. 6C is an example of an image obtained by the first scan stage 52. The light belt-shaped region TB indicates the base portion, and the dark belt-shaped region TM indicates the metal pattern portion. In the region TM, there is no region where the density level is significantly different. As described above, in the image obtained by the first scan stage 52, it is rare that the density level of the image corresponding to the area where dust or the like is attached becomes extremely low.

  FIG. 6D is an example of an image obtained by the second scan stage 66. A dark belt-like region TB indicates a base portion, a light belt-like region TM indicates a metal pattern portion, and a region TD whose density level is significantly higher than the surroundings on the region TM indicates dust or the like. As described above, when dust or the like adheres to the metal pattern portion, in the image obtained by the second scan stage 66, the density level of the portion to which dust or the like adheres may increase.

  From the above description, it can be seen that it is sufficient to detect a region having a low density level in the image obtained by the first scan stage 52 and a high density level in the image obtained by the second scan stage 66 as a pit.

Accordingly, the computer 82 extracts a region having a remarkably low density level in the image obtained by the first scan stage 52, and extracts a region having a remarkably high density level in the image obtained by the second scan stage 66, What is necessary is just to determine that the said area | region is a pit when each extracted area | region is substantially the same position. Thereby, the defect of the three-dimensional shape which generate | occur | produced in the metal pattern part can be detected reliably.
(Marking unit)
As shown in FIG. 1, between the guide 44 and the guide 46, a marking unit 86 is provided for marking at a predetermined position of the package pattern detected as having a defect.

As described above, the image obtained by the reflected light of the light beam irradiated from the oblique direction of the CSP tape and the image obtained by the reflected light of the light beam irradiated from above the CSP tape are used in combination to form on the CSP tape. It is possible to accurately inspect a three-dimensional shape defect generated in the formed metal pattern.
<Second Embodiment>
Subsequently, an inspection apparatus according to a second embodiment of the present invention will be described.

  In the first embodiment, a case has been described in which a defect having a three-dimensional shape generated in a metal pattern portion is inspected based on images obtained by two scan stages. In the second embodiment, 1 A case will be described in which a three-dimensional shape defect generated in a metal pattern portion is inspected based on images obtained by two scan stages. In the following, differences from the first embodiment will be described.

As shown in FIG. 7, the inspection apparatus 100 according to the second embodiment includes a scan stage 102 between a first feed roller 36 and a second feed roller 38.
(Scan stage)
As shown in FIG. 8, a table 104 is arranged on the scan stage 102. Air is ejected from the table 104 toward the CSP tape 16, and a thin air layer is formed between the CSP tape 16 and the table 104.

  Each presser roller 106 is a driven roller that freely rotates, and abuts on the upper surface of the CSP tape 16 to limit the upward movement of the CSP tape 16.

  As shown in FIG. 8, an image reading unit including a lens 108 and a color CCD line sensor 110 is disposed immediately above the center of the table 104 in the conveyance direction of the CSP tape 16. Further, an R-color light irradiation device (line light source) 112 for irradiating the lower part of the CCD line sensor 60 with an R-color light beam is arranged on the upstream side in the transport direction of the CSP tape 16, and downstream in the transport direction of the CSP tape 16. A B-color light irradiation device (line light source) 114 for irradiating the lower part of the CCD line sensor 60 with a B-color light beam is disposed. Each of the R color light irradiation device 112 and the B color light irradiation device 114 irradiates light beams of the respective colors along optical paths LR and LB indicated by alternate long and short dash lines.

  The R-color light irradiation device 112 and the B-color light irradiation device 114 are provided on the CSP tape 16 with a plurality of LEDs arranged along the width direction of the CSP tape 16 (the front and back direction in FIG. 8) and the light beam emitted from the LEDs. It is comprised with the light-guide plate irradiated to a line shape toward. Here, the LED of the R color light irradiation device 112 emits a red (R) light beam, and the LED of the B color light irradiation device 114 emits a blue (B) light beam.

  Further, the R-color light irradiation device 112 and the B-color light irradiation device 114 emit light toward one point when viewed from the side in the tape transport direction. As a result, a red light beam and a blue light beam are superimposed on the surface (upper surface) of the CSP tape 16 and irradiated in a line shape in the tape width direction.

  The CCD line sensor 110 has pixels (RGB) arranged in the width direction of the CSP tape 16.

  The CSP tape 16 is wound around each feed roller 106, and is fed at a constant speed in one direction as each feed roller 106 rotates. The surface is imaged.

  Next, an image obtained by the scan stage 102 will be described.

  FIG. 9 shows an optical path of a light beam irradiated by each of the R color light irradiation device 112 and the B color light irradiation device 114 and reflected by the CSP tape 16, and an image to be captured.

  First, with reference to FIG. 9A, a case where the CSP tape 16 in which pits are generated is irradiated will be described. As shown in FIG. 9A, in the present embodiment, a V-shaped pit is described as an example, but the shape of the pit inspected by the inspection apparatus 100 is not limited to the V-shape.

  An arrow R1 indicates an optical path when the R color light beam irradiated by the R color light irradiation device 112 is reflected in a region where no pit is generated. As indicated by the arrow R1, the reflected light reflected in the region where no pit is generated travels in an oblique direction with respect to the optical axis of the CCD line sensor 110, and therefore the amount of light incident on the CCD line sensor 110 is small.

  An arrow R2 indicates an optical path when the R-color light beam irradiated by the R-color light irradiation device 112 is reflected by the slope region on the downstream side of the pit. As indicated by the arrow R3, the reflected light reflected by the slope area on the downstream side of the pit travels along the optical axis of the CCD line sensor 110, so that the amount of light incident on the CCD line sensor 110 is large.

  An arrow R3 indicates an optical path when the R-color light beam irradiated by the R-color light irradiation device 112 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow R2, the reflected light reflected by the slope region on the upstream side of the pit travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 110, so the amount of light incident on the CCD line sensor 110 is Very few. For this reason, the area corresponding to the slope area on the upstream side of the R color image is shaded.

  An arrow B1 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected in a region where no pit is generated. As indicated by the arrow B1, the reflected light reflected in the region where no pits are generated travels in an oblique direction with respect to the optical axis of the CCD line sensor 110, so that the amount of light incident on the CCD line sensor 110 is small.

  An arrow B2 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow B3, the reflected light reflected by the slope region on the upstream side of the pit travels along the optical axis of the CCD line sensor 110, so that the amount of light incident on the CCD line sensor 110 is large.

  An arrow B3 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected by the slope region on the downstream side of the pit. As indicated by the arrow B2, the reflected light reflected by the slope region on the downstream side of the pit travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 110, so the amount of light incident on the CCD line sensor 110 is Very few. For this reason, the area corresponding to the slope area on the downstream side of the B color image is shaded.

  Therefore, when the R color image and the B color image of the CSP tape 16 where pits are generated are superimposed, the upstream slope region becomes a shadow region of the R color image, and B color appears, and the downstream slope region is B. R color appears in the shaded area of the color image.

  Next, with reference to FIG. 9 (B), the case where the CSP tape 16 in which the protrusion has occurred is irradiated will be described. As shown in FIG. 9B, in the present embodiment, an inverted V-shaped protrusion is described as an example, but the shape of the protrusion inspected by the inspection apparatus 100 is limited to an inverted V-shape. Absent.

  An arrow R4 indicates an optical path when the R color light beam irradiated by the R color light irradiation device 112 is reflected in a region where no pit is generated. As indicated by the arrow R4, the reflected light reflected in the area where no pits are generated travels in an oblique direction with respect to the optical axis of the CCD line sensor 110, so that the amount of light incident on the CCD line sensor 110 is small.

  An arrow R5 indicates an optical path when the R color light beam irradiated by the R color light irradiation device 112 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow R5, the reflected light reflected by the slope region on the upstream side of the pit travels along the optical axis of the CCD line sensor 110, so that the amount of light incident on the CCD line sensor 110 is large.

  An arrow R6 indicates an optical path when the R-color light beam irradiated by the R-color light irradiation device 112 is reflected by the slope region on the downstream side of the pit. As indicated by an arrow R6, the reflected light reflected by the slope region downstream of the pits travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 110, so the amount of light incident on the CCD line sensor 110 is Very few. For this reason, the area corresponding to the slope area on the downstream side of the R color image is shaded.

  An arrow B4 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected in an area where no pit is generated. As indicated by the arrow B4, the reflected light reflected in the region where no pit is generated travels in an oblique direction with respect to the optical axis of the CCD line sensor 110, and therefore the amount of light incident on the CCD line sensor 110 is small.

  An arrow B5 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected by the slope region on the downstream side of the pit. As indicated by the arrow B5, the reflected light reflected by the slope area on the downstream side of the pit travels in a direction substantially perpendicular to the optical axis of the CCD line sensor 110, so the amount of light incident on the CCD line sensor 110 is Many.

  An arrow B6 indicates an optical path when the B-color light beam irradiated by the B-color light irradiation device 114 is reflected by the slope region on the upstream side of the pit. As indicated by the arrow B6, the reflected light reflected by the slope region on the upstream side of the pit travels along the optical axis of the CCD line sensor 110, so the amount of light incident on the CCD line sensor 110 is very small. For this reason, the region corresponding to the slope region on the upstream side of the B color image is shaded.

  Therefore, when the R color image and the B color image of the CSP tape 16 where the protrusion is generated are superimposed, the upstream slope region becomes a shadow region of the B color image, and the R color appears, and the downstream slope region is R. B color appears in the shaded area of the color image.

  Further, from the contents shown in FIGS. 9A and 9B, B color appears in the slope region that descends toward the upstream side in the transport direction of the CSP tape 16, and the slope that rises toward the upstream side in the transport direction of the CSP tape 16. It can also be seen that R color appears in the region. That is, it is possible to determine whether the three-dimensional shape defect generated in the metal pattern portion is a pit or a bulge from the positional relationship between the areas where the respective colors appear.

  The CCD line sensor 110 sends an image signal corresponding to the amount of incident light to the computer 82 (see FIG. 7).

  Next, the characteristics of an image obtained by the scan stage 102 will be described with reference to FIG.

  FIG. 10A is an example of an image obtained when the CSP tape 16 in which pits are generated is irradiated. The dark belt-like region TB indicates the base portion, and the light belt-like region TM indicates the metal pattern portion. Of the areas where the density level on the area TM is significantly different from the surrounding area, the upper area (red area in the color image) TPR indicates the slope area on the downstream side of the pit, and the lower area (blue area in the color image). Area) TPB indicates a slope area on the upstream side of the pit.

  FIG. 10B is an example of an image obtained when the CSP tape 16 in which the protrusion is generated is irradiated. The dark belt-like region TB indicates the base portion, and the light belt-like region TM indicates the metal pattern portion. Of the areas where the density level on the area TM is significantly different from the surrounding area, the upper area (blue area in the color image) TPB indicates the slope area on the downstream side of the bulge, and the lower area (red area in the color image). Area) TPR indicates the slope area on the upstream side of the ledge.

  On the other hand, FIG. 10C shows an example of an image of a region where dust or the like is attached to the metal pattern portion. The dark belt-like region TB indicates the base portion, the light belt-like region TM indicates the metal pattern portion, and the region TD whose density level is significantly higher than the surroundings on the region TM indicates dust or the like.

  When there is no defect in the three-dimensional shape, the incident angles of the light beams of the respective colors are substantially the same, and the light amounts of the light beams of the respective colors incident on the CCD line sensor 110 are substantially the same. The changes are almost the same. For this reason, when dust etc. adhere, it is rare that only one color image is detected.

  As described above, when light beams of different colors are irradiated from different directions, one color appears in an image of a region where a defect of a three-dimensional shape is generated according to the slope of the defect of the three-dimensional shape. Therefore, the computer 82 extracts a region where each color appears in the image (hereinafter, referred to as a colored region), and detects a three-dimensional shape defect based on at least one of the positional relationship and the shape of each extracted colored region. The detection based on the positional relationship may be performed, for example, by obtaining the center position distance between the colored regions. A distance range that can be regarded as a three-dimensional shape defect is determined in advance, and whether or not it is a pit is determined based on whether or not the distance between the colored regions extracted from the image obtained by the scan stage 102 is within the distance range. On the other hand, the detection based on the shape may be performed, for example, by determining whether the colored region is a snowman shape as shown in FIG. Furthermore, the computer 82 determines whether the three-dimensional shape defect is a pit or a bulge based on the positional relationship between the colored regions.

  As described above, by irradiating the CSP tape with light beams of different colors from different directions, a single scan stage reliably detects a three-dimensional shape defect generated in a metal pattern portion in a short time inspection. be able to. Further, by irradiating the CSP tape with light beams of different colors from different directions, it is possible to further determine the shape of a three-dimensional shape defect generated in the metal pattern portion.

  As shown in FIG. 11, a G-color epi-illumination unit that is composed of a G-color light irradiation device (line light source) 120 and a half mirror 122 and irradiates a light beam perpendicularly to the CSP tape 16 is provided above the table 104. Further, a G color transmitted light irradiation device (line light source) 124 that irradiates a light beam from the back surface of the CSP tape 16 may be further disposed in the table 104. The G color light irradiation device 120 and the G color transmitted light irradiation device 124 are configured to include an LED that irradiates a green (G) light beam, and the G color light irradiation device 120 and the G color transmitted light irradiation device 124 have the G color along the optical axis LG. Irradiate a light beam. The amount of G-color incident light to the CCD line sensor 110 increases when there is a defect on the metal pattern portion. By detecting defects in the CSP tape using a combination with the image obtained by the reflected light of G color, it is possible to inspect the three-dimensional shape defects generated in the metal pattern with higher accuracy.

  In addition, the R color light irradiation device and the B color light irradiation device are configured to be installed at opposite positions on the upstream side and the downstream side in the transport direction of the CSP tape with respect to the CCD line sensor. Should just be installed in the position which opposes centering on a CCD line sensor. For example, when the installation positions of the R color light irradiation device and the B color light irradiation device are switched, the positional relationship of the regions where the respective colors appear is switched. Further, when the R color light irradiation device and the B color light irradiation device are installed at opposing positions in the width direction of the CSP tape, the regions where the respective colors appear are arranged in the width direction of the CSP tape.

  Further, in the above-described embodiment, the case where the light beam is irradiated from both the upstream side and the downstream side of the CSP tape below the CCD line sensor has been described, but either the upstream side or the downstream side of the CSP tape is described. The defect may be inspected based on the image obtained by the light beam irradiated from the oblique direction and the image obtained by the light beam irradiated along the optical axis of the CCD line sensor.

  In the above-described embodiment, the case of inspecting the three-dimensional shape defect generated in the metal pattern portion of the CSP tape has been described. However, the present invention is not limited to this, and the three-dimensional shape defect generated in the surface of another article is inspected. In this case, the present invention can be applied.

It is a schematic block diagram of the inspection apparatus of the 1st Embodiment of this invention. It is a schematic block diagram of a 1st scan stage. It is a figure explaining the reflected light in a 1st scan stage. It is a schematic block diagram of a 2nd scan stage. It is a figure explaining the reflected light in a 2nd scan stage. It is a figure which shows an example of the image obtained in the 1st scan stage and the 2nd scan stage. It is a schematic block diagram of the inspection apparatus of the 2nd Embodiment of this invention. It is a schematic block diagram of the scan stage of 2nd Embodiment. It is a figure explaining the reflected light in the scan stage of 2nd Embodiment. It is a figure which shows an example of the image obtained in the scan stage of 2nd Embodiment. It is a figure which shows the modification of the scan stage of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inspection apparatus 16 CSP tape 52 1st scanning stage 54 Table 60 CCD line sensor 62 1st irradiation apparatus 64 2nd irradiation apparatus 66 2nd scanning stage 74 CCD line sensor 76 3rd irradiation apparatus 82 Computer 100 Inspection Device 102 Scan stage 110 CCD line sensor 112 R color light irradiation device 114 B color light irradiation device

Claims (6)

A plurality of irradiation means for irradiating the inspection object with light from different directions;
Imaging means for taking images of each light reflected by the inspection object by being irradiated by the plurality of irradiation means;
Detecting means for detecting a defect having a three-dimensional shape from each image picked up by the image pickup means;
Inspection device with The irradiating means includes at least one of a first irradiating means for irradiating the inspection object with light from a first oblique direction and a second irradiating means for irradiating the inspection object with light from a second oblique direction. Direction irradiation means, and third irradiation means for irradiating the inspection object with light from above,
The inspection apparatus according to claim 1, wherein the third irradiation unit performs irradiation at a timing different from that of the oblique direction irradiation unit.   The inspection apparatus according to claim 2, further comprising a fourth irradiation unit that irradiates the inspection target with light from below at the same timing as the third irradiation unit.   The detecting means has a density level that is outside a first predetermined range in an image captured by the imaging means when light is irradiated by the oblique direction irradiation means, and the upper direction irradiation means is irradiated with light. 4. A region having a density level outside the second predetermined range is extracted from the image picked up by the image pickup means, and a three-dimensional shape defect is detected based on each of the extracted regions. The inspection device described in 1.   The inspection apparatus according to claim 1, wherein each of the plurality of irradiation units emits light of different colors.   The detection unit extracts a region having a density level outside a predetermined range from each image captured by the imaging unit, and detects a three-dimensional shape defect based on at least one of a positional relationship and a shape of each extracted region. The inspection apparatus according to claim 5 to be detected.

Images