JP2014038045A - Inspection device, illumination, inspection method, program and substrate producing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique such as an inspection device which can accurately detect foreign matter adhering onto an inspection face of an inspection object.SOLUTION: An inspection face of an inspection object is irradiated with light including components of blue or violet wavelength areas at an irradiation angle of 10 or less degrees. The inspection object having the inspection face irradiated with the light by illumination is captured, and an image of the inspection object is subjected to binarization processing. On the basis of the image obtained by binarization processing, foreign matter on the inspection face is detected.

Description

  The present technology relates to an inspection apparatus that detects foreign matter adhering to an inspection surface of an inspection object.

  2. Description of the Related Art Conventionally, an inspection apparatus that detects a foreign substance attached to an inspection surface of an inspection object is widely known (see, for example, Patent Document 1). In this type of inspection apparatus, first, light is irradiated to an inspection object such as a substrate by illumination, and then the inspection object illuminated by the illumination is imaged by an imaging unit. And the foreign material on a test target object is detected based on the imaged image.

JP 2010-169611 A

  In such a technical field, a technique capable of detecting a foreign object with high accuracy is desired.

  In view of the circumstances as described above, an object of the present technology is to provide a technique such as an inspection apparatus that can accurately detect a foreign matter attached to an inspection surface of an inspection object.

  The inspection apparatus according to the present technology includes illumination that irradiates light including a component in a blue or violet wavelength region with an irradiation angle of 10 degrees or less on an inspection surface of an inspection object.

  By irradiating light at an irradiation angle of 10 degrees or less with respect to the inspection surface of the inspection object, a portion that is a convex portion on the inspection surface can be illuminated brightly and a flat portion can be darkened. Furthermore, by using light including a blue or violet wavelength region, it is possible to increase the contrast (luminance difference) between the convex portion and the flat portion. Thereby, it becomes possible to detect the foreign substance (convex part) adhering on the inspection surface with high accuracy.

The inspection apparatus may further include a transport unit and an adjustment mechanism.
The said conveyance part has a guide part which guides the said test target object along one direction, and conveys the said test target object along the said one direction.
The adjustment mechanism adjusts the height of the guide portion or the inspection object so that the upper surface of the guide portion is below the inspection surface when the light is irradiated to the inspection surface. To do.

  When the illumination irradiation angle is low, the shadow of the guide part may occur on the inspection surface of the inspection object. Therefore, in this inspection apparatus, the height of the guide portion or the inspection object is adjusted so that the height of the upper surface of the guide portion is equal to or lower than the inspection surface. Thereby, it can prevent that the shadow of a guide part arises on the test | inspection surface of a test target object.

In the inspection apparatus, the guide portion may include a first guide and a second guide.
The first guide guides the inspection object in the one direction.
The second guide is attached to the first guide at a position corresponding to an inspection position where the inspection object is inspected.
In this case, the adjustment mechanism may adjust the height of the second guide so that the upper surface of the second guide has a height equal to or lower than the inspection surface.

  The said inspection apparatus WHEREIN: The said illumination may irradiate the said light from the direction orthogonal to the said one direction.

  When the first illumination is arranged so as to irradiate light from a direction orthogonal to the one direction (conveyance direction of the inspection object), a shadow by the guide portion is particularly likely to occur. Therefore, in such a case, it is particularly effective to prevent the shadow of the guide by adjusting the height of the guide portion or the inspection object.

The inspection apparatus may further include an imaging unit and a control unit.
The imaging unit captures an image of the inspection object that is illuminated by the light with respect to the inspection surface, and acquires an image of the inspection object.
The control unit detects foreign matter on the inspection surface based on the image.

  In the inspection apparatus, the control unit may perform a binarization process on the image of the inspection object and detect a foreign matter on the inspection surface based on the image obtained by the binarization process.

The inspection apparatus may further include a display unit and other illumination.
The display unit has a screen.
The other illumination irradiates light at an irradiation angle exceeding 10 degrees with respect to the inspection surface of the inspection object.
In this case, the imaging unit may acquire an image of the inspection object by imaging the inspection object irradiated with the light on the inspection surface by the other illumination.
In this case, the control unit may display the image obtained by the binarization process on the screen by superimposing the image on the image acquired by irradiating light with the other illumination.

  Accordingly, the user can accurately inspect the foreign matter by visually recognizing the image displayed on the screen.

  In the inspection apparatus, the control unit may apply a non-inspection mask to the image of the inspection object and detect the foreign matter in a region other than the non-inspection mask.

  Thereby, it can prevent that objects other than a foreign material are recognized as a foreign material. In addition, the detection of foreign matter in an area that does not need to be inspected is prevented.

  In the inspection apparatus, the control unit may be capable of generating a non-inspection mask.

  In the inspection apparatus, the control unit may acquire region information in which the inspection surface is divided into a plurality of regions according to color density, and generate the non-inspection mask based on the region information.

  Thereby, the area | region of a specific color density can be made into a non-inspection area | region.

In the inspection apparatus, the inspection object may have a formed object on the inspection surface.
In this case, the control unit may acquire position information of the formed object and generate the non-inspection mask based on the position information.

  Thereby, it can prevent that a formation is recognized as a foreign material.

In the inspection apparatus, the inspection object may have a pattern on the inspection surface.
In this case, the control unit may acquire edge line information of the pattern and generate the non-inspection mask based on the edge line information.

  Thereby, it can be prevented that the edge line of the pattern is detected as a foreign substance.

  In the inspection apparatus, the control unit may expand the edge line at a predetermined expansion rate, and generate the expanded edge line as the non-inspection mask.

  The illumination according to the present technology irradiates the inspection surface of the inspection object with light including a component in the blue or violet wavelength region at an irradiation angle of 10 degrees or less.

The inspection method according to the present technology includes irradiating the inspection surface of the inspection object with light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less.
The inspection object in which the light is illuminated by the illumination with respect to the inspection surface is imaged, and an image of the inspection object is acquired.
A foreign object on the inspection surface is detected based on the image.

A program according to the present technology is stored in an inspection device.
Irradiating the inspection surface of the inspection object with light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less;
Imaging the inspection object illuminated by the light with respect to the inspection surface, and obtaining an image of the inspection object;
Detecting foreign matter on the inspection surface based on the image.

The manufacturing method of the board | substrate which concerns on this technique includes irradiating the light which contains the component of a blue or purple wavelength range with respect to the test | inspection surface of a board | substrate with an irradiation angle of 10 degrees or less.
The board on which the light is illuminated by the illumination with respect to the inspection surface is imaged, and an image of the board is acquired.
A foreign object on the inspection surface is detected based on the image.
The quality of the substrate is determined based on information on the foreign matter on the inspection surface.
The substrate determined to be non-defective is advanced to the next step in the substrate manufacturing process.

  As described above, according to the present technology, it is possible to provide a technique such as an inspection apparatus that can accurately detect foreign matters attached on the inspection surface of an inspection object.

It is a figure which shows the mounting system which concerns on this embodiment. It is a side view which shows the foreign material inspection apparatus which concerns on this embodiment. It is a perspective view which shows the conveyance part which a foreign material inspection apparatus has. It is the fragmentary sectional view which looked at the guide part which a conveyance part has from the side. It is a block diagram which shows the structure of a foreign material inspection apparatus. It is a flowchart which shows the process of a foreign material inspection apparatus. FIG. 7 is a supplementary diagram for explaining the processing illustrated in FIG. 6, and is a diagram illustrating a process when an image obtained by irradiation with the first oblique illumination is processed. It is a figure which shows a mode when the image obtained by the binarization process is superimposed and displayed on the whole image of a board | substrate. It is a flowchart which shows an example of a process when a non-inspection mask is produced | generated. FIG. 10 is a supplementary diagram for explaining the flowchart illustrated in FIG. 9, and is a diagram illustrating an entire image of the substrate displayed on the screen. It is a flowchart which shows the other example about a process when a non-inspection mask is produced | generated. It is a supplementary figure for demonstrating the flowchart shown in FIG. 11, and is a figure which shows a mode when a mask area is produced | generated. It is a flowchart which shows another example about a process when a non-inspection mask is produced | generated. It is a supplementary figure for demonstrating the flowchart shown in FIG. 13, and is a figure which shows a mode when a mask area is produced | generated. It is a figure which shows a mode when a non-inspection mask is applied.

  Hereinafter, embodiments according to the present technology will be described with reference to the drawings.

<Overall Configuration of Mounting System 200>
FIG. 1 is a diagram illustrating a mounting system 200 according to the present embodiment. The mounting system 200 is a system for manufacturing a printed circuit board by mounting various electronic components such as resistors, capacitors, and inductors on a printed wiring board.

  As shown in FIG. 1, the mounting system 200 includes a screen printing apparatus 101, a foreign substance inspection apparatus 100 (2D), a print inspection apparatus 102 (3D), a mounting apparatus 103, a foreign substance inspection apparatus 100, and a mounting inspection in order from the upstream side. A device 104 (3D) is provided. The mounting system 200 includes a reflow furnace 105, a cleaning device 106, a drying device 107, a foreign matter inspection device 100, and a final inspection device 108 (3D).

  The screen printing apparatus 101 supplies the solder 7 on a screen provided with a plurality of small openings, and slides the squeegee on the screen. Thereby, the solder 7 is printed on the board | substrate 1 arrange | positioned under the screen. The foreign matter inspection apparatus 100 determines whether or not the foreign matter 4 has adhered to the inspection surface 1a (front surface) of the substrate 1 on which the solder 7 is printed, and the substrate 1 determined to be non-defective is the next-stage print inspection device 102. Pass to. The print inspection apparatus 102 three-dimensionally inspects the board 1 on which the solder 7 is printed to determine whether the board 1 is good or not, and transfers the board 1 determined to be non-defective to the next-stage mounting apparatus 103.

  The mounting apparatus 103 mounts various electronic components such as a resistor, a capacitor, and an inductor on the substrate 1 at a position corresponding to a portion where the solder 7 is printed. The foreign matter inspection apparatus 100 inspects whether or not the foreign matter 4 is adhered on the inspection surface 1a of the substrate 1 on which the electronic component is mounted, and delivers the substrate 1 determined to be a non-defective product to the next-stage mounting inspection device 104. . The mounting inspection device 104 three-dimensionally inspects the substrate 1 on which the electronic component is mounted, determines whether the substrate 1 is acceptable, and transfers the substrate 1 determined to be non-defective to the next-stage reflow furnace 105.

  The reflow furnace 105 reflows the substrate 1 on which the electronic component is mounted, melts the solder 7, and connects the wiring and the electronic component via the solder 7. The cleaning device 106 cleans the flux and the like attached to the surface of the substrate 1 after the reflow process. The drying device 107 dries the cleaned substrate 1.

  The foreign matter inspection apparatus 100 inspects whether the foreign matter 4 is adhered on the inspection surface 1a of the substrate 1 after cleaning, and transfers the substrate 1 determined to be non-defective to the final inspection apparatus 108 at the next stage. The final inspection device 108 three-dimensionally inspects the substrate 1 on which the electronic component is mounted to determine whether the substrate 1 is acceptable.

<Configuration of Foreign Object Inspection Device 100 and Configuration of Each Unit>
Next, the configuration of the foreign matter inspection apparatus 100 and the configuration of each part of the foreign matter inspection apparatus 100 will be described.

  FIG. 2 is a side view showing the foreign matter inspection apparatus 100. FIG. 3 is a perspective view illustrating the transport unit 10 included in the foreign matter inspection apparatus 100. FIG. 4 is a partial cross-sectional view of the guide unit 11 included in the transport unit 10 as viewed from the side. FIG. 5 is a block diagram illustrating a configuration of the foreign matter inspection apparatus 100.

  As shown in FIG. 1, the foreign matter inspection apparatus 100 shown in FIG. 2 to FIG. 5 is arranged at a subsequent stage of the screen printing apparatus 101, the mounting apparatus 103, and the drying apparatus 107. The inspection object to be inspected by the foreign matter inspection apparatus 100 is, for example, the substrate 1 on which the solder 7 is printed (before mounting the electronic component) or the substrate 1 on which the electronic component is mounted (before the reflow processing and after the reflow processing). ) Etc. The substrate 1 has, for example, a rectangular shape in plan view, and has an alignment mark in the vicinity of a corner on a diagonal line.

  Referring to FIGS. 2 to 5, foreign object inspection apparatus 100 is configured to transfer substrate 1 from below at a conveyance unit 10 that conveys substrate 1 along the X-axis direction and an inspection position where substrate 1 is inspected. And a backup unit 30 to be supported. Further, the foreign matter inspection apparatus 100 applies an oblique illumination unit 40 including a plurality of oblique illuminations 41 and 42 that irradiate light from an oblique direction to the inspection surface 1 a of the substrate 1, and an inspection surface 1 a of the substrate 1 An upper illumination unit 50 that emits light from directly above, and an imaging unit 60 that images the substrate 1 disposed at the inspection position from above. Furthermore, the foreign substance inspection apparatus 100 includes a control unit 70, a storage unit 71, a display unit 72, an input unit 73, and a communication unit 74.

  The oblique illumination units 40 are provided on both sides of the foreign object inspection apparatus 100 in the front-rear direction (Y-axis direction) with the transport unit 10 interposed therebetween. The oblique illumination unit 40 includes a first oblique illumination 41 and a second oblique illumination 42. Each of these oblique illuminations 41 and 42 has a long shape along the transport direction (X-axis direction) of the substrate 1, and the substrate 1 from the direction (Y-axis direction) orthogonal to the transport direction of the substrate 1. The test surface 1a is irradiated with light.

  The first oblique illumination 41 is arranged so that light can be irradiated at an irradiation angle θ1 of 10 degrees or less with respect to the inspection surface 1a of the substrate 1. On the other hand, the second oblique illumination 42 is arranged so that light can be irradiated onto the inspection surface 1a of the substrate 1 at an irradiation angle θ2 exceeding 10 degrees. For example, the irradiation angle θ2 of the second oblique illumination 42 is about 40 degrees to 70 degrees.

  The first oblique illumination 41 irradiates the inspection surface 1a of the substrate 1 with light containing a component in the blue or violet wavelength region (purple 380 to 450 nm, blue 450 to 495 nm). The first oblique illumination 41 irradiates the inspection surface 1 a of the substrate 1 with blue or violet light, or irradiates the inspection surface 1 a of the substrate 1 with white light including blue or violet light. To do.

  On the other hand, the second oblique illumination 42 irradiates the inspection surface 1a of the substrate 1 with light including a component in the red wavelength region (620 nm to 750 nm). The first oblique illumination 41 irradiates the inspection surface 1a of the substrate 1 with red light or irradiates the inspection surface 1a of the substrate 1 with white light including red light.

  The upper illumination unit 50 irradiates light at an irradiation angle of 90 ° with respect to the inspection surface 1 a of the substrate 1. The upper illumination unit 50 is typically illumination that emits white light. The upper illumination unit 50 includes a surface emitting illumination unit 51 and a coaxial epi-illumination 52. The surface emitting illumination unit 51 is disposed between the substrate 1 and the imaging unit 60 above the substrate 1 and irradiates light from above the substrate 1 toward the substrate 1 by surface emission. The surface emitting illumination unit 51 has a rectangular plate shape as a whole, and has an opening 51a penetrating in the vertical direction at a position near the center. By forming the opening 51a, the imaging unit 60 can image the substrate 1 from above the substrate 1.

  On the other hand, since the opening 51a is provided in the surface-emitting illumination unit 51 in order to secure the field of view of the imaging unit 60, the substrate 1 is sufficiently illuminated from above the substrate 1 only by the light from the surface-emitting illumination unit 51. I can't.

  For this reason, the coaxial epi-illumination 52 is disposed at a position corresponding to the opening 51 a of the surface emitting illumination unit 51. The coaxial epi-illumination 52 is arranged above the surface-emitting illumination unit 51 and coaxial with the optical axis of the imaging unit 60. The coaxial epi-illumination 52 has a housing 53, and the housing 53 is provided with openings for securing the field of view of the imaging unit 60 at the top and bottom. Inside the housing 53, a half mirror 54 disposed obliquely at a position corresponding to the opening, and a surface-emitting epi-illumination 55 that emits light toward the half mirror 54 are disposed. The

  The half mirror 54 can reflect the light emitted from the incident illumination 55, change the direction of the light by 90 °, and guide the light toward the substrate 1 side. Further, the half mirror 54 can transmit the light incident from the substrate 1 side and guide it to the imaging unit 60 side.

  The imaging unit 60 is disposed above the substrate 1 and images the substrate 1 from above through an opening provided in the coaxial incident illumination 52 and an opening 51 a provided in the surface light emitting illumination unit 51. The imaging unit 60 is illuminated by the first oblique illumination 41 with the substrate 1 illuminated with light containing a blue or violet component, or with the second oblique illumination 42 with light containing a red component. An image of the substrate 1 is obtained by capturing an image of the substrate 1. Further, the imaging unit 60 captures an image of the substrate 1 on which light (typically white light) is simultaneously illuminated by the surface emitting illumination unit 51 and the coaxial incident illumination 52, and acquires an image of the substrate 1.

  The imaging unit 60 includes an imaging element such as a CCD sensor (CCD: Charge Coupled Device) or a CMOS sensor (CMOS: Complementary Metal Oxide Semiconductor), and an optical system such as an imaging lens.

  The backup unit 30 supports the substrate 1 transported to the inspection position by the transport unit 10 from below and moves the substrate 1 to a predetermined height. The backup unit 30 includes a backup plate 31, a plurality of support pins 32 erected on the backup plate 31, and a plate lifting mechanism 33 that lifts and lowers the backup plate 31.

  2, 3, and 4, the transport unit 10 includes a guide unit 11 that guides the substrate 1 along the X direction. The guide portion 11 includes a pair of first guides 12 and a pair of second guides 13.

  The first guide 12 is disposed in the X-axis direction, and guides the substrate 1 along the X-axis direction. The first guide 12 is a plate-like member having a shape that is long in the X-axis direction. A plurality of support portions 14 that support the first guide 12 from below are provided below the first guide 12. A conveyor belt 15 is provided on the inner surface of the first guide 12. The transport unit 10 can transport the substrate 1 to the inspection position by driving the conveyor belt 15 and can discharge the substrate 1 that has been inspected.

  The second guide 13 is attached to the first guide 12 so as to be movable in the vertical direction at a position corresponding to the inspection position where the substrate 1 is inspected. The second guide 13 is formed such that the upper end portion of the plate-like member is bent toward the center side of the transport unit 10, and the first guide 13 covers the outer surface and the upper surface of the first guide 12. The guide 12 is attached.

  A height adjustment mechanism 20 is provided between the first guide 12 and the second guide 13. In the height adjusting mechanism 20, when light is irradiated to the inspection surface 1 a of the substrate 1 by the first oblique illumination 41, the height of the upper surface of the second guide 13 is set so that the inspection surface 1 a of the substrate 1. The height of the second guide 13 is adjusted so as to be the following height.

  The height adjusting mechanism 20 includes a plurality of guide mechanisms 21 for moving the second guide 13 along the Z-axis direction with respect to the first guide 12, and a drive source for moving the second guide 13. The two actuators 24 are included.

  The guide mechanism 21 includes a Z-axis guide 22 that is fixed to the outer surface of the first guide 12 along the Z-axis direction, and a slider 23 that can slide on the Z-axis guide 22. The outer surface of the slider 23 is fixed to the inner surface of the second guide 13.

  The actuator 24 includes an actuator body 25 and a movable portion 26 that is moved in the Z-axis direction with respect to the actuator body 25. The actuator body 25 is fixed to the first guide 12 via a first attachment member 27 fixed to the inner surface side of the first guide 12 by a method such as screwing. The movable portion 26 is fixed to the second guide 13 via a second attachment member 28 attached to the outer surface side of the second guide 13 by a method such as screwing.

  The control unit 70 is configured by, for example, a CPU (Central Processing Unit) and the like, and comprehensively controls each unit of the foreign matter inspection apparatus 100. The processing of the control unit 70 will be described in detail later.

  The storage unit 71 includes a nonvolatile memory used as a work area for the control unit 70 and a nonvolatile memory in which various data and programs necessary for the processing of the control unit 70 are stored. The various programs may be read from a portable recording medium such as an optical disk or a semiconductor memory.

  The display unit 72 is configured by, for example, a liquid crystal display or the like, and displays an image captured by the imaging unit 60 and various data on the screen. The input unit 73 includes a keyboard, a mouse, a touch panel, and the like, and inputs various instructions from the user. The communication unit 74 transmits information to other devices in the mounting line and receives information from other devices.

<Description of operation>
Next, the operation of the foreign matter inspection apparatus 100 will be described. FIG. 6 is a flowchart showing processing of the foreign matter inspection apparatus 100. FIG. 7 is a supplementary diagram for explaining the processing shown in FIG. 6, and is a diagram showing a process when an image obtained by irradiation with the first oblique illumination 41 is processed.

  First, the control unit 70 drives the conveyor belt 15 of the transport unit 10 to transport the substrate 1 to the inspection position (step 101). Next, the control unit 70 drives the plate raising / lowering mechanism 33 of the backup unit 30 to move the backup unit 30 to a predetermined height and move the substrate 1 to a predetermined height.

  Next, the control unit 70 drives the actuator 24 of the height adjustment mechanism 20 to move the movable unit 26 downward. In response to this, the second guide 13 is moved downward with respect to the first guide 12 (see FIG. 4).

  Thereby, the height of the inspection surface 1 a of the substrate 1 can be made higher than the upper surface of the guide portion 11. Therefore, it is possible to prevent a shadow from being generated on the substrate 1 when the oblique illumination unit 40 irradiates the substrate 1 with light from an oblique direction. In particular, in this embodiment, since light is irradiated onto the substrate 1 at a low irradiation angle of 10 degrees or less by the first oblique illumination 41, it is particularly effective to prevent the occurrence of shadows by the guide portion 11. .

  Typically, if the inspection surface 1 a of the substrate 1 can be positioned higher than the upper surface of the guide portion 11, the occurrence of shadows by the guide portion 11 can be prevented. Accordingly, the height of the substrate 1 may be adjusted by the backup unit 30, and the inspection surface 1 a of the substrate 1 may be positioned higher than the upper surface of the guide unit 11. Such a method can also prevent the occurrence of shadows.

  Next, the control part 70 images the board | substrate 1 by irradiating light to the test | inspection surface 1a of the board | substrate 1 by illumination (step 102). In step 102, the control unit 70 first turns on the upper illumination unit 50 (surface emitting illumination unit 51 and coaxial epi-illumination 52), and irradiates light onto the inspection surface 1a of the substrate 1 from the upper side. The imaging unit 60 images the substrate 1 irradiated with light by the unit 50. Then, the control unit 70 turns off the upper illumination unit 50.

  Next, the control unit 70 turns on the first oblique illumination 41 to irradiate the inspection surface 1a of the substrate 1 with light containing a blue or purple component at an irradiation angle θ1 of 10 degrees or less. . Then, the control unit 70 images the substrate 1 illuminated by the first oblique illumination 41 with the imaging unit 60.

  Referring to FIG. 7, the second view from the top shows a partially enlarged view of the image of the substrate 1 imaged by irradiating blue light with the first oblique illumination 41. With reference to the top view of FIG. 7, a solder resist 2 is formed on the substrate 1, and the metal pad 3 is not covered with the solder resist 2 and is exposed from the upper surface of the substrate 1. In this example, the foreign matter 4 is attached to the upper part of the metal pad 3 or in the vicinity of the metal pad 3.

  Referring to the second diagram from the top in FIG. 7, it can be seen that the edge portion of the metal pad 3 and the foreign material 4 portion are brightly illuminated and the other portions are dark. This is because when light is irradiated at an irradiation angle of 10 degrees or less, a flat portion on the surface of the substrate 1 can be darkened and a portion that is a convex portion can be illuminated brightly. Furthermore, in the upper diagram of FIG. 7, the contrast (brightness difference) between the bright portion and the dark portion is large. This is because light in the blue or violet wavelength region can have a greater contrast than light in other wavelength regions.

  If the image of the board | substrate 1 is acquired, the control part 70 will recognize the position of the board | substrate 1 next (step 103). In step 103, the control unit 70 recognizes the position of the substrate 1 based on the information on the position of the alignment mark included in the image of the substrate 1 acquired by turning on the upper illumination unit 50. Note that the image used for position recognition of the substrate 1 may be an image obtained by turning on the second oblique illumination 42.

  Next, the control unit 70 applies a non-inspection mask to the image of the substrate 1 acquired by light irradiation by the first oblique illumination 41. The controller 70 detects the foreign matter 4 in a region other than the non-inspection mask. The non-inspection mask is stored in the storage unit 71 in advance. A method for generating the non-inspection mask will be described later in detail.

  With reference to the third drawing from the top in FIG. 7, for example, a non-inspection mask is applied to the edge portion of the metal pad 3. That is, although the edge portion of the metal pad 3 is brightly illuminated in the same manner as the foreign material 4, the metal pad 3 is not the foreign material 4, so the edge portion of the metal pad 3 is not inspected so that the edge portion is not detected as the foreign material 4. A mask is applied.

  When the non-inspection mask is applied, the control unit 70 then binarizes the image of the substrate 1 acquired by turning on the first oblique illumination 41 using a predetermined threshold (step 105). With reference to the lowermost diagram in FIG. 7, the foreign matter 4 that is a bright portion in the image of the substrate 1 is identified by the binarization process.

  In this embodiment, since the contrast of the part (bright part) which is the foreign material 4 and the part (dark part) which is not the foreign material 4 are large, the foreign material 4 can be identified correctly. In particular, it is possible to accurately identify even a small foreign object 4 or a scratch.

  Next, the control unit 70 determines whether or not the foreign object 4 has been detected based on the image obtained by the binarization process (see the bottom diagram in FIG. 7) (step 106). When the foreign material 4 is not detected (NO in step 106), the control unit 70 determines that the substrate 1 is a non-defective product (step 107). And the control part 70 controls the conveyor belt 15 of the conveyance part 10, discharges | emits the board | substrate 1, and delivers the board | substrate 1 to the apparatus arrange | positioned in the next stage in the mounting line. Thereby, the board | substrate 1 is advanced to the next manufacturing process.

  On the other hand, when the foreign object 4 is detected (YES in Step 106), the control unit 70 outputs information such as the position of the foreign object 4 and stores it in the storage unit 71 (Step 108). Next, the control unit 70 causes the image obtained by the binarization processing to be superimposed on the entire image of the substrate 1 and displayed on the screen (step 109).

  FIG. 8 is a diagram illustrating a state in which an image obtained by the binarization process is displayed superimposed on the entire image of the substrate 1.

  As shown in FIG. 8, an image obtained by the binarization process, that is, an image indicating the position of the foreign material 4 is superimposed on the entire image of the substrate 1. The entire image of the substrate 1 is an image obtained by irradiating the substrate 1 with light by the upper illumination unit 50 or the second oblique illumination 42 (other illumination). The position of the foreign material 4 is displayed in a color such as red or pink so that it is conspicuous with respect to the entire image of the substrate 1.

  In the example shown in FIG. 8, a foreign object detection list 80 is displayed on the upper right. In the foreign object detection list 80, one item corresponds to one foreign object 4. The detection list 80 can be scrolled according to a user operation.

  In the items in the list, two names, “foreign matter” and “metal pad”, are given. Here, when it is determined that the foreign object 4 is attached to a position in contact with the metal pad 3, the name “metal pad” is given to the foreign object 4. The name “foreign matter” is given to the foreign matter 4 that is not in contact with the metal pad 3. The control unit 70 reads the position information of the metal pad 3 from the storage unit 71, so that the foreign object 4 is named “foreign material” or “metal pad”. Judging.

  When one item in the detection list 80 is selected by the user, the selected item is highlighted. Further, the foreign object 4 corresponding to the selected item is enlarged and displayed (see the lower right in FIG. 8). In addition, the image acquired by irradiating light by the upper side illumination part 50 or the 2nd oblique illumination 42 is used for the image displayed in an enlarged manner. That is, an image obtained by binarization processing (see the lowermost diagram in FIG. 7) is not displayed in an overlapping manner.

  By displaying the image shown in FIG. 8 on the screen, the user can intuitively and easily determine the number, position, size, and the like of the foreign material 4. The foreign object detection list 80 is provided with one check box 81 for one item. For example, the check box 81 is checked when the foreign matter 4 is large or the foreign matter 4 has adhered to an important position on the substrate 1. When the check box 81 is checked, the control unit 70 stores the foreign matter 4 corresponding to the checked item in the storage unit 71.

  If the user visually determines that there is no problem with the substrate 1, the user inputs an instruction to advance the substrate 1 to the next manufacturing process via the input unit 73. On the other hand, when the user determines that there is a problem with the substrate 1, the user inputs an instruction to discard the substrate 1 or to proceed to a process of reuse.

[Generation method of non-inspection mask]
Next, a method for generating a non-inspection mask will be described. There are roughly three methods for generating non-inspection masks. Therefore, in the following, these three generation methods will be described in order. Note that these three generation methods can be combined as appropriate.

  FIG. 9 is a flowchart illustrating an example of processing when a non-inspection mask is generated. FIG. 10 is a supplementary diagram for explaining the flowchart shown in FIG. 9, and is a diagram showing an entire image of the substrate 1 displayed on the screen.

  First, after positioning the substrate 1 at the inspection position, the control unit 70 turns on the upper illumination unit 50 or the second oblique illumination 42 to irradiate the inspection surface 1a of the substrate 1 with light. Is imaged by the imaging unit 60 (step 201). Next, the control unit 70 performs alignment setting based on the position information of the alignment mark included in the image of the substrate 1 (step 202).

  Next, the control unit 70 displays the entire image of the substrate 1 on the screen of the display unit 72 (step 203). On the upper side of FIG. 10, an example of the entire image of the substrate 1 displayed on the screen is shown. In the example shown in FIG. 10, a plurality of slits 5 are provided on the substrate 1, and the plurality of slits 5 have a darker (darker) color density than other portions on the substrate 1.

  When the entire image of the substrate 1 is displayed on the screen, the control unit 70 next acquires, from the storage unit 71, region information in which the inspection surface 1a on the substrate 1 is divided into a plurality of regions according to the color density. (Step 204). This area information is stored in the storage unit 71 in advance. For example, in the example shown in FIG. 10, the area where the slit 5 is formed has a darker (darker) color density than the area other than the slit 5. Therefore, in this case, the inspection surface 1a on the substrate 1 is divided into nine regions in total including eight regions where the slits 5 are formed and other regions.

  The area information may be generated by the control unit 70. In this case, the control unit 70 acquires an image of the substrate 1 captured by the upper illumination unit 50 or the second oblique illumination 42 being turned on, and determines a luminance value at each point on the substrate 1. Then, the control unit 70 divides the inspection surface 1a into a plurality of regions based on the luminance value.

  When the area information is acquired, the control unit 70 next highlights the area designated by the user via the input unit 73 among the plurality of areas divided according to the color density (step 205). The lower part of FIG. 10 shows a state in which eight areas where the slits 5 are formed are designated by the user and these eight areas are highlighted. As a method of highlighting the area designated by the user, for example, a method of displaying the designated area in red, pink, or the like, or blinking the area can be cited.

  Next, the control unit 70 stores the area designated by the user in the storage unit 71 as a non-inspection mask (step 206). In the example illustrated in FIG. 10, the eight regions where the slits 5 are formed are stored in the storage unit 71 as non-inspection masks.

  In this example, the area where the slit 5 is formed is described as an example of the area specified by the user. However, the area specified by the user may be a print area or the like.

  Through the processing as described above, the user can arbitrarily set a non-inspection area. In particular, in the portion where the slit 5 is provided, the foreign matter 4 that is unnecessary in the foreign matter detection is often detected. Therefore, it is particularly effective to exclude the region in which the slit 5 is formed by the above method from the inspection area.

  Next, another example of generation of a non-inspection mask will be described. FIG. 11 is a flowchart illustrating another example of processing when a non-inspection mask is generated. FIG. 12 is a supplementary diagram for explaining the flowchart shown in FIG. 11 and shows a state when a mask area is generated.

  First, the control unit 70 acquires the position data of the opening of the screen used for screen printing of the screen printing apparatus 101 from the storage unit 71 (step 301). The opening position data is stored in the storage unit 71 in advance.

  As described above, the screen is provided with a plurality of openings, and the solder 7 is printed on the substrate 1 through the plurality of openings. Therefore, the position data of the opening coincides with the position where the solder 7 is formed on the substrate 1 as long as printing is accurate. In step 301, opening position data is acquired as position information of the solder 7 (formed product) formed on the substrate 1.

  When the position data of the opening is acquired, the control unit 70 then acquires the alignment coordinates of the substrate 1 from the storage unit 71, and collates the position of the substrate 1 and the position of the opening (step 302). As the alignment coordinates of the substrate 1, for example, data set by the alignment setting in step 202 described above is used.

  The upper drawing of FIG. 12 shows a state when the position of the opening is compared with the position of the substrate 1. In FIG. 12, metal wiring 6 and solder resist 2 are formed on the substrate 1. A part of the metal wiring 6 is covered with the solder resist 2, and another part of the metal wiring 6 is not covered with the solder resist 2 and is exposed as the metal pad 3 from the upper surface of the substrate 1. In the example shown in FIG. 12, the position of the opening (that is, the solder 7 is formed) corresponds to the position near the center of the metal pad 3.

  When the position of the substrate 1 and the position of the opening are collated, the control unit 70 then masks the region surrounded by the opening (step 303). Then, the control unit 70 acquires the expansion coefficient from the storage unit 71 and multiplies the masked area by the expansion coefficient to expand the area (step 305). In the lower part of FIG. 12, the expanded mask area is indicated by hatching.

  Once the mask area is expanded, the control unit 70 stores the expanded mask area in the storage unit 71 as a non-inspection mask (step 306).

  By the processing as described above, the non-inspection mask can be appropriately set for the region where the solder 7 is formed.

  Next, still another example of generation of a non-inspection mask will be described. FIG. 13 is a flowchart showing still another example of processing when a non-inspection mask is generated. FIG. 14 is a supplementary diagram for explaining the flowchart shown in FIG. 13 and shows a state when a mask area is generated.

  First, after the substrate 1 is positioned at the inspection position, the control unit 70 turns on the first oblique illumination 41 to irradiate light onto the inspection surface 1a of the substrate 1, and the substrate irradiated with the light. 1 is imaged by the imaging unit 60 (step 401). In addition, the control unit 70 turns on the upper illumination unit 50 to irradiate the inspection surface 1 a of the substrate 1 with light, and the imaging unit 60 images the substrate 1 irradiated with the light.

  Next, the control unit 70 acquires the alignment coordinates of the substrate 1 from the storage unit 71 and recognizes the position of the substrate 1 (step 402). As the alignment coordinates of the substrate 1, for example, data set by the alignment setting in step 202 described above is used.

  Next, the control unit 70 performs difference image calculation processing based on the two images acquired in step 401 (step 403). In step 403, the value obtained by multiplying the luminance value of the image of the substrate 1 acquired by lighting the first oblique illumination 41 by a predetermined multiple a and the substrate 1 acquired by lighting the upper illumination unit 50. A difference from a value obtained by multiplying the luminance value of the image by a predetermined multiple b is calculated.

  Next, the control unit 70 binarizes the data obtained by the difference image calculation process based on a predetermined threshold (step 404). Next, the control unit 70 acquires a noise removal coefficient from the storage unit 71, and removes noise from the binarized data using the noise removal coefficient (step 405).

  Next, the control unit 70 obtains an edge layer by applying a morphological operation to the data after noise removal (step 406). Then, the control unit 70 stores the edge layer obtained from the difference image in the storage unit 71 (step 407).

  Next, the control unit 70 turns on the first oblique illumination 41 to irradiate the inspection surface 1a of the substrate 1 with light, and the imaging unit 60 images the substrate 1 irradiated with the light (step). 408). Next, the control unit 70 acquires the alignment coordinates of the substrate 1 from the storage unit 71 and recognizes the position of the substrate 1 (step 409).

  Next, the control unit 70 acquires a smoothing coefficient from the storage unit 71 (step 410), and smoothes the image of the substrate 1 obtained by turning on the first oblique illumination 41 (step 411). Next, the control unit 70 applies an Laplacian method, a Canny method, or the like to the data after the smoothing process, and executes an edge extraction process (step 412).

  In step 412, an edge can be extracted from the difference image between the image obtained by turning on the second oblique illumination 42 and the image obtained by turning on the upper illumination unit 50. In this case, in step 408, two images for obtaining the difference image are captured.

  When the edge extraction process is executed, the control unit 70 then acquires a noise removal coefficient from the storage unit 71, and removes noise from the data after the edge extraction process using the noise removal coefficient (step 413). Next, the control unit 70 obtains an edge layer by applying a morphological operation to the data after noise removal (step 414). Then, the control unit 70 masks the edge layer obtained in step 414 and the edge layer obtained in step 407 described above (step 415).

  Next, the control unit 70 acquires the expansion coefficient from the storage unit 71 (step 416), and multiplies the masked region by the expansion coefficient to expand the mask area (step 417). Next, the control unit 70 stores the expanded mask area as a non-inspection mask in the storage unit 71 (step 418).

  In the example shown in FIG. 14, the substrate 1 has a pattern such as a resist pattern or a circuit pattern on the inspection surface 1a. In this case, the edge line of the resist, the edge line of the metal pad, and the edge line of the metal wiring 6 covered with the solder resist 2 are extracted. Then, these edge lines are expanded at a predetermined expansion rate to generate a mask area (see the lower diagram in FIG. 14).

  With the processing shown in FIG. 13, a non-inspection mask can be appropriately set for edges of a resist pattern, a circuit pattern, and the like.

  FIG. 15 is a diagram illustrating a state when a non-inspection mask is applied. In the upper part of FIG. 15, a partially enlarged view of the inspection surface 1 a of the substrate 1 is shown. In the example shown in FIG. 15, the solder 7 is printed on the metal pad 3, and the thread-like foreign matter 4 is attached on the inspection surface 1 a of the substrate 1. The lower part of FIG. 15 shows an area to which a non-inspection mask is applied, an area recognized as solder 7, an area recognized as foreign matter 4, and the like.

  In the substrate inspection, first, the substrate 1 shown on the upper side of FIG. 15 is irradiated with light containing a blue or purple component by the first oblique illumination 41 at an irradiation angle θ1 of 10 degrees or less, The substrate 1 irradiated with the light is imaged by the imaging unit 60. At this time, an image in which the edge of the thread-like foreign material 4, the solder 7, and the metal pad 3 is brighter than other portions is acquired. Further, although the degree of brightness is low compared to the brightness of the foreign matter 4 or the like, the edge of the resist and the metal wiring 6 under the resist pattern are also brighter than other portions.

  Then, a non-inspection mask as shown in the lower diagram of FIG. 15 is applied to the image of the substrate 1 acquired by turning on the first oblique illumination 41. Thereafter, binarization processing is executed, and a bright area is detected in a portion other than the non-inspection mask. Of the detection areas detected as brighter than the other parts, the detection area that touches the mask area based on the aperture data is recognized as the solder 7. On the other hand, a detection area that is detected as brighter than other portions and that does not touch the mask area based on the aperture data is recognized as the foreign object 4.

<Various modifications>
The foreign matter inspection apparatus 100 may be able to execute processing of a three-dimensional inspection apparatus (print inspection apparatus 102, mounting inspection apparatus 104, and final inspection apparatus 108) arranged at the subsequent stage of the foreign substance inspection apparatus 100. In other words, the foreign matter inspection apparatus 100 may be capable of executing substrate inspection by three-dimensional inspection in addition to foreign matter inspection by two-dimensional inspection. In this case, the three-dimensional inspection apparatus arranged at the subsequent stage of the foreign substance inspection apparatus 100 can be omitted. In this case, in addition to the oblique illumination unit 40 and the upper illumination unit 50, illumination for acquiring an image for three-dimensional measurement is specially provided in the foreign matter inspection apparatus 100.

This technique can also take the following composition.
(1) An inspection apparatus including illumination that irradiates light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less with respect to an inspection surface of an inspection object.
(2) The inspection apparatus according to (1) above,
A guide unit that guides the inspection object along one direction, and a conveyance unit that conveys the inspection object along the one direction;
An adjustment mechanism that adjusts the height of the guide part or the inspection object so that the upper surface of the guide part is below the inspection surface when the light is irradiated to the inspection surface. An inspection device further provided.
(3) The inspection apparatus according to (2) above,
The guide portion is attached to the first guide at a position corresponding to a first guide for guiding the inspection object in the one direction and an inspection position where the inspection object is inspected. A second guide,
The adjustment mechanism adjusts the height of the second guide so that the upper surface of the second guide is below the inspection surface.
(4) The inspection apparatus according to (2) or (3) above,
The illumination device irradiates the light from a direction orthogonal to the one direction.
(5) The inspection apparatus according to any one of (1) to (5) above,
An imaging unit that images the inspection object illuminated by the illumination with respect to the inspection surface and acquires an image of the inspection object;
An inspection apparatus further comprising: a control unit that detects foreign matter on the inspection surface based on the image.
(6) The inspection apparatus according to (5) above,
The said control part binarizes the image of the said test target object, and detects the foreign material on the said test | inspection surface based on the image obtained by the said binarization process.
(7) The inspection apparatus according to (6) above,
A display unit having a screen;
And further comprising other illumination that irradiates light at an irradiation angle exceeding 10 degrees with respect to the inspection surface of the inspection object,
The imaging unit captures the inspection object irradiated with the light to the inspection surface by the other illumination, and acquires an image of the inspection object.
The said control part superimposes the image obtained by the said binarization process on the image acquired by irradiating light with the said other illumination, and displays it on the said screen.
(8) The inspection apparatus according to any one of (5) to (7) above,
The control unit applies a non-inspection mask to the image of the inspection object, and detects the foreign matter in a region other than the non-inspection mask.
(9) The inspection apparatus according to (8) above,
The control unit is capable of generating a non-inspection mask.
(10) The inspection apparatus according to (9) above,
The said control part acquires the area | region information by which the said test | inspection surface was divided into several area | region according to color density, and produces | generates the said non-inspection mask based on the said area information.
(11) The inspection apparatus according to (9) or (10) above,
The inspection object has a formation on the inspection surface,
The said control part acquires the positional information on the said formation, and produces | generates the said non-inspection mask based on the said positional information Inspection apparatus.
(12) The inspection apparatus according to any one of (9) to (11),
The inspection object has a pattern on the inspection surface;
The control unit acquires information on edge lines of the pattern, and generates the non-inspection mask based on the information on the edge lines.
(13) The inspection apparatus according to (12) above,
The said control part expand | swells an edge line with a predetermined expansion rate, and produces | generates the said expanded edge line as said non-inspection mask.
(14) Illumination that irradiates the inspection surface of the inspection object with light including a component in the blue or violet wavelength region at an irradiation angle of 10 degrees or less.
(15) irradiating the inspection surface of the inspection object with light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less;
Imaging the inspection object that is illuminated by the illumination with respect to the inspection surface, obtaining an image of the inspection object,
An inspection method for detecting foreign matter on the inspection surface based on the image.
(16) In the inspection device,
Irradiating the inspection surface of the inspection object with light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less;
Imaging the inspection object illuminated by the light with respect to the inspection surface, and obtaining an image of the inspection object;
Detecting a foreign matter on the inspection surface based on the image.
(17) irradiating the inspection surface of the substrate with light containing a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less;
Imaging the substrate illuminated with the light by the illumination with respect to the inspection surface, obtaining an image of the substrate,
Detect foreign matter on the inspection surface based on the image,
Based on the information of foreign matter on the inspection surface, determine the quality of the substrate,
The board | substrate manufacturing method which advances the said board | substrate determined to be non-defective to the next process in a board | substrate manufacturing process.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 1a ... Inspection surface 2 ... Solder resist 3 ... Metal pad 4 ... Foreign material 5 ... Slit 6 ... Metal wiring 7 ... Solder 10 ... Conveyance part 11 ... Guide part 12 ... 1st guide 13 ... 2nd guide 20 ... Adjustment mechanism 30 ... backup unit 40 ... oblique illumination unit 41 ... first oblique illumination 42 ... second oblique illumination 50 ... upper illumination unit 60 ... imaging unit 70 ... control unit 100 ... foreign matter inspection apparatus

Claims (17)

An inspection apparatus comprising illumination that irradiates light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less with respect to an inspection surface of an inspection object. The inspection apparatus according to claim 1,
A guide unit that guides the inspection object along one direction, and a conveyance unit that conveys the inspection object along the one direction;
An adjustment mechanism that adjusts the height of the guide part or the inspection object so that the upper surface of the guide part is below the inspection surface when the light is irradiated to the inspection surface. An inspection device further provided. The inspection apparatus according to claim 2,
The guide portion is attached to the first guide at a position corresponding to a first guide for guiding the inspection object in the one direction and an inspection position where the inspection object is inspected. A second guide,
The adjustment mechanism adjusts the height of the second guide so that the upper surface of the second guide is below the inspection surface. The inspection apparatus according to claim 2,
The illumination device irradiates the light from a direction orthogonal to the one direction. The inspection apparatus according to claim 1,
An imaging unit that images the inspection object illuminated by the illumination with respect to the inspection surface and acquires an image of the inspection object;
An inspection apparatus further comprising: a control unit that detects foreign matter on the inspection surface based on the image. The inspection apparatus according to claim 5,
The said control part binarizes the image of the said test target object, and detects the foreign material on the said test | inspection surface based on the image obtained by the said binarization process. The inspection apparatus according to claim 6,
A display unit having a screen;
And further comprising other illumination that irradiates light at an irradiation angle exceeding 10 degrees with respect to the inspection surface of the inspection object,
The imaging unit captures the inspection object irradiated with the light to the inspection surface by the other illumination, and acquires an image of the inspection object.
The said control part superimposes the image obtained by the said binarization process on the image acquired by irradiating light with the said other illumination, and displays it on the said screen. The inspection apparatus according to claim 5,
The control unit applies a non-inspection mask to the image of the inspection object, and detects the foreign matter in a region other than the non-inspection mask. The inspection apparatus according to claim 8,
The control unit is capable of generating a non-inspection mask. The inspection apparatus according to claim 9,
The said control part acquires the area | region information by which the said test | inspection surface was divided into several area | region according to color density, and produces | generates the said non-inspection mask based on the said area information. The inspection apparatus according to claim 9,
The inspection object has a formation on the inspection surface,
The said control part acquires the positional information on the said formation, and produces | generates the said non-inspection mask based on the said positional information Inspection apparatus. The inspection apparatus according to claim 9,
The inspection object has a pattern on the inspection surface;
The control unit acquires information on edge lines of the pattern, and generates the non-inspection mask based on the information on the edge lines. The inspection apparatus according to claim 12,
The said control part expand | swells an edge line with a predetermined expansion rate, and produces | generates the said expanded edge line as said non-inspection mask. Illumination that irradiates the inspection surface of the inspection object with light including a component in the blue or violet wavelength region at an irradiation angle of 10 degrees or less. Irradiate the inspection surface of the inspection object with light containing a component in the blue or violet wavelength region at an irradiation angle of 10 degrees or less,
Imaging the inspection object that is illuminated by the illumination with respect to the inspection surface, obtaining an image of the inspection object,
An inspection method for detecting foreign matter on the inspection surface based on the image. Inspection equipment
Irradiating the inspection surface of the inspection object with light including a component in a blue or violet wavelength region at an irradiation angle of 10 degrees or less;
Imaging the inspection object illuminated by the light with respect to the inspection surface, and obtaining an image of the inspection object;
Detecting a foreign matter on the inspection surface based on the image. Irradiate the inspection surface of the substrate with light containing a component in the blue or violet wavelength region at an irradiation angle of 10 degrees or less,
Imaging the substrate illuminated with the light by the illumination with respect to the inspection surface, obtaining an image of the substrate,
Detect foreign matter on the inspection surface based on the image,
Based on the information of foreign matter on the inspection surface, determine the quality of the substrate,
The board | substrate manufacturing method which advances the said board | substrate determined to be non-defective to the next process in a board | substrate manufacturing process.