WO2019239501A1 - Foreign matter inspection device and foreign matter inspection method - Google Patents

Foreign matter inspection device and foreign matter inspection method Download PDF

Info

Publication number
WO2019239501A1
WO2019239501A1 PCT/JP2018/022470 JP2018022470W WO2019239501A1 WO 2019239501 A1 WO2019239501 A1 WO 2019239501A1 JP 2018022470 W JP2018022470 W JP 2018022470W WO 2019239501 A1 WO2019239501 A1 WO 2019239501A1
Authority
WO
WIPO (PCT)
Prior art keywords
inspection
foreign matter
color
inspection object
foreign
Prior art date
Application number
PCT/JP2018/022470
Other languages
French (fr)
Japanese (ja)
Inventor
栄一 佐野
瑞樹 中村
Original Assignee
株式会社エフケー光学研究所
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社エフケー光学研究所 filed Critical 株式会社エフケー光学研究所
Priority to JP2020524994A priority Critical patent/JP6980241B2/en
Priority to PCT/JP2018/022470 priority patent/WO2019239501A1/en
Priority to CN201880094385.9A priority patent/CN112236671A/en
Priority to TW108119929A priority patent/TWI721447B/en
Publication of WO2019239501A1 publication Critical patent/WO2019239501A1/en

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/94—Investigating contamination, e.g. dust
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
    • G01N21/956—Inspecting patterns on the surface of objects

Definitions

  • the present invention relates to a foreign matter inspection apparatus and a foreign matter inspection method for inspecting foreign matters attached to various substrates such as a liquid crystal color filter.
  • Patent Document 1 an imaging unit is focused on the surface of an object to be inspected, foreign matter on the surface of the object to be inspected is detected from the captured image, and the imaging unit is focused on the back surface of the object to be inspected.
  • a foreign matter detection device that picks up an image and detects foreign matter on the back surface of the object to be inspected from the taken image.
  • Patent Document 2 discloses a foreign matter inspection apparatus capable of inspecting foreign matter attached to the front and back surfaces of a glass substrate with high accuracy. Therefore, this foreign matter inspection device can switch between detection of foreign matter attached to the surface of the glass substrate and detection of foreign matter attached to the back surface of the glass substrate by changing the relative position of the light projecting position and the light receiving position. It is said.
  • the color filter that is being manufactured may have an electrode provided on the back surface of the glass substrate or may have holes formed in the glass substrate.
  • the color filter being manufactured is inspected in a state where it is installed on a pedestal or the like, but the pedestal itself may be damaged. In the inspection in the manufacturing process of the color filter, it is necessary to inspect foreign matters attached to the resist side (surface) applied to the glass substrate.
  • the electrodes, holes, or pedestal foreign matter, scratches, and holes provided on the glass substrate are also imaged in the surface inspection, making it difficult to distinguish them from foreign matter. Therefore, for areas that are known in advance, such as electrodes, holes, pedestal scratches, and holes, a mask area that is treated as a dead zone area when image processing is performed on a captured image, and a foreign substance inspection area And what is not done.
  • the dead zone area becomes large, the area for inspecting foreign matter is reduced. Further, even if foreign matter adheres to the dead zone, no foreign matter has adhered, and as described above, the photomask is damaged or the quality of the product is impaired.
  • the foreign substance inspection apparatus employs the first configuration described below.
  • a foreign matter inspection apparatus for inspecting foreign matter attached to the surface of an inspection object A light source unit that irradiates the inspection object with illumination light having a complementary color relationship with the surface color of the inspection object;
  • a detection unit that detects foreign matter based on an image captured by the imaging unit.
  • the foreign substance inspection apparatus (second configuration) is the first configuration
  • the detection unit detects a foreign object using a mask that designates a dead zone area to be excluded from the detection target of the foreign object in the captured image,
  • the dead zone region is smaller than the size of a structure located on the back surface of the inspection object or a hole provided in the inspection object.
  • the foreign substance inspection apparatus (third configuration) according to the present invention is the second configuration,
  • the mask is formed based on an image photographed by irradiating the inspection object with the illumination light having a complementary color relationship with the surface color of the inspection object.
  • the foreign matter inspection apparatus (fourth configuration) according to the present invention is the second or third configuration
  • the detection unit changes a mask according to the surface color of the inspection target.
  • the foreign matter inspection apparatus includes any one of the first to fourth configurations.
  • the illumination light emitted from the light source is incoherent light.
  • the foreign matter inspection apparatus includes any one of the first to fifth configurations.
  • the inspection object is a substrate having a surface coated with a color resist film,
  • the illumination light has a complementary color relationship with the color of the color resist film.
  • the light source unit changes the color of the illumination light according to the surface color of the inspection target.
  • the foreign matter inspection apparatus includes any one of the first to seventh configurations.
  • the imaging unit is disposed at a position where the specularly reflected light reflected by the inspection object is not received and a position where the scattered light of the foreign matter attached to the surface of the inspection object is received.
  • the foreign substance inspection method (9th structure) which concerns on this invention is the following.
  • the inspection object is irradiated with illumination light having a complementary color relationship with the surface color of the inspection target, and the inspection of the foreign matter is performed based on the photographed image. It is possible to reduce or eliminate the dead zone for electrodes located on the back of the object, holes provided in the inspection object, scratches on the base, etc. Inspection accuracy can be improved.
  • Side view showing the configuration of the foreign matter inspection apparatus in the present embodiment The figure which shows the manufacturing process of the color filter used as the test object of this embodiment
  • Side view for explaining a photographing configuration of the foreign matter inspection apparatus of the present embodiment Schematic diagram for explaining the inspection target region in the captured image of the present embodiment
  • Schematic diagram for explaining a mask used in image processing of the present embodiment Flow chart showing foreign substance inspection process of this embodiment
  • FIG. 1 is a perspective view showing a configuration of a foreign matter inspection apparatus 1 in the present embodiment.
  • the foreign matter inspection apparatus of the present embodiment is illuminated with LED (Light Emitting Diode) line light sources 3a and 3b (corresponding to the “light source part” of the present invention) that illuminate the inspection object 4 installed on the base 5.
  • the imaging units 2a to 2r that shoot the inspection object 4 and the information processing device (not shown) that performs image processing on the images captured by the imaging units 2a to 2r and detects foreign matter attached to the surface of the inspection object 4. And corresponds to the “detection unit” of the present invention.
  • the inspection object 4 of the present embodiment is, for example, a transparent substrate (a glass substrate or the like) on which a surface color resist is applied during the color filter manufacturing process.
  • a transparent substrate a glass substrate or the like
  • the manufacturing process of the color filter will be described in detail later.
  • the foreign matter inspection apparatus 1 is not limited to the color filter in the middle of the manufacturing process, but can be used in various fields where a transparent substrate is used.
  • the imaging units 2a to 2r are arranged in a matrix above the inspection object 4.
  • the imaging range P of the imaging unit 2k is indicated by hatching.
  • a part of the imaging range P is used as an effective inspection area, and the remaining imaging range is not used for detection of a foreign object (ineffective inspection area).
  • the imaging units 2a to 2r arranged in a matrix form are arranged so that a part of each effective inspection region overlaps, so that the entire inspection object 4 can be the inspection object. In this way, it is possible to inspect the entire surface of the inspection object 4 by photographing with the imaging units 2a to 2r.
  • the number and arrangement of the imaging units 2a to 2r are not limited to the form shown in FIG. 1, and can be appropriately determined according to various conditions such as the size and shape of the inspection object 4.
  • the LED line light sources 3 a and 3 b as the light source unit irradiate the surface of the inspection object 4 with the illumination light L from the lateral direction of the inspection object 4.
  • the imaging units 2a to 2r of the present embodiment receive the regular reflection light of the illumination light L from the inspection object 4 at an angle at which scattered light from the foreign object is received in order to detect the foreign material attached to the surface of the inspection object 4. It is arranged to face the angle that does not. With such an arrangement, the scattered light of the foreign matter is received without being obstructed by the regular reflection light, and the accuracy of foreign matter detection can be improved.
  • incoherent light such as the LED line light sources 3a and 3b of the present embodiment or a fluorescent lamp instead of coherent light such as laser light for the light source unit.
  • coherent light a structure such as an electrode located on the back surface of the inspection object or a hole provided in the inspection object is photographed in actual size.
  • incoherent light as illumination light and selecting the color of illumination light, the amount of illumination light transmitted to the inspection object is suppressed, and as a result, a structure such as an electrode located on the back surface of the inspection object, or The hole or the like provided in the inspection object can be recognized (observed) smaller than the actual size, and the inspection object area can be enlarged.
  • FIG. 2 is a side view showing the configuration of the foreign matter inspection apparatus 1 in the present embodiment.
  • 2 is a side view of the imaging units 2a to 2f in FIG.
  • LED line light source 3a, 3b irradiates the illumination light L to the surface of the test object 4 from the horizontal direction.
  • the illumination light L is preferably incident so as to be substantially parallel to the surface of the inspection object 4, that is, incident so that the light strikes only the foreign matter located on the surface 4 of the inspection object 4.
  • the surface of the inspection object 4 does not become a flat surface due to the distortion of the inspection object 4 or the pedestal 5, it is necessary to tilt the inspection object 4 slightly.
  • the inclination angle of the illumination light L with respect to the surface of the inspection object 4 is preferably inclined toward the inspection object 4 within a range of 0 to 5 degrees when the state parallel to the XY plane is 0 degree. More preferably, it is within 0 to 3 degrees. In FIG. 2, the inclination angle of the illumination light L is shown exaggerated larger than actual.
  • the imaging units 2a to 2f of the present embodiment have an angle for receiving scattered light from the foreign matter attached to the surface of the inspection object 4, and do not receive the regular reflection light of the illumination light L from the inspection object 4. It is arranged to face the angle.
  • the imaging units 2a to 2c receive the scattered light from the foreign matter caused by the illumination light L of the LED line light source 3a, and the vertical direction (Z-axis direction) and the angle E (1 degree ⁇ E ⁇ 20 degrees).
  • the imaging units 2d to 2f are arranged at an angle E in the direction different from the imaging units 2a to 2c on the XZ plane so as to receive the scattered light from the foreign matter by the illumination light L of the LED line light source 3b. ing.
  • the imaging units 2a to 2c mainly receive the scattered light scattered by the foreign matter by the illumination light L from the LED line light source 3a, and are affected by the regular reflection light of the LED line light sources 3a and 3b. It is difficult.
  • the imaging units 2d to 2f mainly receive the scattered light scattered by the foreign matter by the illumination light L from the LED line light source 3b, and are hardly affected by the regular reflection light of the LED line light sources 3a and 3b. Although not shown, the imaging units 2a to 2f are in a state of being oriented in the vertical direction in the YZ plane.
  • FIG. 3 is a diagram illustrating a manufacturing process of a color filter.
  • a black matrix 42 is formed on a transparent substrate 41 such as a glass substrate.
  • the formation of the black matrix 42 is performed by exposure and development as in the case of the color resist 43R described later, but the description thereof is omitted here.
  • a red color resist 43R is applied on a transparent substrate 41 on which a black matrix 42 is formed.
  • the inspection object 4 is a state where the color resist 43R is applied.
  • the exposure is performed by placing the photomask 44 on the upper side.
  • the foreign matter adheres to the color resist 43R, the foreign matter is exposed to the photo resist.
  • the mask 44 may be damaged. Since the photomask 44 is extremely expensive, the financial damage due to breakage is great. Further, if the manufacture of the color filter is continued without noticing the damage of the photomask 44 due to the foreign matter, the color filter itself will be defective. The loss of the color filter causes, for example, deterioration of a display image in the liquid crystal display device.
  • FIG. 3D shows the cured color resist 43R.
  • the cured color resist 43G is added as shown in FIG. 3E.
  • the process of FIGS. 3B and 3C is performed on the blue color resist 43B, whereby the cured color resist 43B is added as shown in FIG. 3E.
  • the foreign matter inspection apparatus 1 according to the present embodiment also sets the inspection target 4 in a state where the green color resist 43G and the blue color resist 43B are applied, and executes the inspection of the foreign matter attached to the surface.
  • FIG. 4 is a hue circle for explaining the relationship between the color of the illumination light L used in the foreign matter inspection apparatus 1 of the present embodiment and the color resist color that is the surface color of the inspection object 4.
  • a hue circle equally divided into 24 blocks is used.
  • FIG. 4A shows the case of the color resist 43G, in which the resist color is red as indicated by an arrow.
  • the colors at the opposite positions are complementary colors.
  • the complementary color is a color that generates white light when additive color is mixed between a certain color light and the complementary color light.
  • the present embodiment by selecting the color of the illumination light L so as to satisfy a predetermined condition according to the surface color of the inspection object 4, a structure such as an electrode located on the back surface of the inspection object 4 or the inspection object It is possible to recognize (observe) holes provided in 4 or scratches on the surface of the pedestal 5 smaller than the actual size.
  • a structure such as an electrode located on the back surface of the inspection object 4 or the inspection object
  • the structures, holes, and scratches on the pedestal 5 of the inspection object 4 described above are observed in actual size on the captured image. Therefore, it is necessary to provide a mask having a dead zone corresponding to the actual size for these structures, holes, and scratches. In the dead zone region, the surface of the inspection object 4 cannot be inspected.
  • the present embodiment by using the color of the illumination light L that satisfies a predetermined condition, it is possible to reduce the dead zone area and enlarge the area for inspecting the foreign matter.
  • the complementary color relationship is a color having a center frequency within a predetermined range from the complementary color of the surface color of the inspection object 4 in the hue circle.
  • the complementary color relationship is a color having a center frequency within a predetermined range from the complementary color of the surface color of the inspection object 4 in the hue circle.
  • Illumination light L having a center frequency for colors within the block range is used.
  • the illumination light L having the center frequency for the color at the position indicated by the arrow is used.
  • Illumination light L having a center frequency in a color within a predetermined range from the complementary color of the above is used.
  • the imaging units 2a to 2r can detect the foreign matter effectively by receiving the scattered light from the foreign matter.
  • the scattering of light by a foreign substance will be described. It is known that when light is incident on microparticles that are foreign matters, the form of scattering varies depending on the size of the microparticles. Scattering by microparticles is roughly classified according to the relationship between the size of microparticles and the wavelength of light. When the size of microparticles is 1/10 of the wavelength of light, Rayleigh scattering can occur. It is known that Mie scattering occurs when the size is larger.
  • the foreign object to be detected in the present embodiment is a broken piece of a glass substrate or the like, and is a foreign object having a size that causes Mie scattering.
  • FIG. 5 is a schematic diagram for explaining Mie scattering, and is a schematic diagram showing a state of scattering when the illumination light L is incident on the spherical microparticle S.
  • FIG. FIG. 5A is a top view showing a state of scattered light
  • FIG. 5B is a side view thereof.
  • the surface of the inspection object 4 is the XY plane
  • the axis orthogonal to the surface of the inspection object is the Z axis
  • the traveling direction of the illumination light L is the positive direction of the X axis.
  • Scattered light appears in an arc in each of the positive and negative directions of the X axis.
  • the scattered light is observed to be larger than the size of the spherical microparticles S, it is possible to efficiently detect the foreign matter attached to the inspection object by observing the scattered light.
  • FIG. 6 shows a captured image 23 (binarized) captured using the foreign matter inspection apparatus 1 of the present embodiment.
  • two transparent spherical fine particles S1 and S2 small bead spheres
  • Circles indicated by broken lines indicate actual positions of the spherical microparticles S ⁇ b> 1 and S ⁇ b> 2 and are not actually shown in the captured image 23.
  • the captured image 23 is a binarized image obtained by photographing the spherical minute particles S1 and S2 with the illumination light L incident in the positive X-axis direction, as in FIG.
  • Scattered light shown in black is captured in the positive and negative X-axis directions of the spherical microparticles S1 and S2.
  • the scattered light from the spherical microparticles S1 and S2 is projected larger than the actual size of the spherical microparticles S1 and S2, and thus is effective for the inspection of the foreign matter attached to the surface of the inspection object 4.
  • spherical microparticles S are used as foreign substances, which is because observation of scattered light is most difficult in a spherical shape.
  • An actual foreign object generally has a shape different from a spherical shape such as a glass piece, and scattered light appears remarkably in such a shape, and its observation is easy.
  • FIG. 7 is a side view for explaining a photographing configuration of the foreign matter inspection apparatus 1 of the present embodiment.
  • the imaging configuration will be described using one imaging unit 2 a as an example.
  • the surface of the inspection object 4 is illuminated with the LED line light source 3a extending in the Y-axis direction, and the scattered light scattered by the foreign matter attached to the inspection object 4 is imaged by the imaging unit 2a.
  • six spherical microparticles S1 to S6 are arranged at equal intervals in the X-axis direction as a sample of foreign matter. These spherical fine particles S1 to S6 are arranged so as to fall within the imaging range T of the imaging unit 2a.
  • the illumination light L is incident substantially parallel to the surface of the inspection object 4, but may be slightly inclined toward the inspection object 4 as described with reference to FIG.
  • the angle E of the imaging unit 2a is set to an angle (in the range of 1 to 20 degrees) such that the regular reflection light by the illumination light L from the LED line light source 3a does not enter.
  • the imaging units 2a to 2 are arranged such that a part of the effective inspection region R1 overlaps. Placed in.
  • FIG. 8 is a schematic diagram for explaining the effective inspection region R1 in the captured image 23 of the present embodiment.
  • an area located on the side where the illumination light L is incident from the LED line light source 3 a in the imaging range T is set as an effective inspection area R ⁇ b> 1 used for the inspection of foreign matter. Further, the remaining area is set as an invalid inspection area R2 that is not used for the inspection of foreign matter.
  • the imaging unit 2 a in which the optical axis of the optical system 22 is orthogonal to the imaging surface 21 is used, the position of the optical axis C ⁇ b> 2 in the captured image 23 is located at the center of the captured image 23.
  • the image center C1 of the effective inspection region R1 is shifted to the side on which the illumination light L is incident because the invalid inspection region R2 is cut out from the captured image 23.
  • FIG. 9 is a schematic diagram for explaining a mask used in image processing according to the present embodiment.
  • the mask is used for designating a dead zone area that is not used for the inspection of foreign matter in the captured image 23.
  • the dead zone region is assigned to positions of structures, holes, scratches, and the like that are known in advance in the inspection object 4, and is intended to prevent erroneous detection of these as foreign matters.
  • incoherent light is used as the illumination light L and the color thereof is selected, so that in particular, structures such as electrodes located on the back surface of the inspection object 4, holes provided in the inspection object 4, pedestal 5 can be recognized (observed) smaller than the actual size. Therefore, it is possible to reduce the dead zone area in the mask or not to provide the dead zone area, and it is possible to enlarge the area other than the dead zone area, that is, the area to be inspected for foreign matter.
  • FIG. 9A is a top view schematically showing the electrode 45b provided on the back surface of the inspection object 4, the hole 45a penetrating the inspection object 4, and a cross-sectional view at the position of the hole 45a.
  • the coordinate system shown in FIG. 9 is the same as that in FIGS. 1 and 2, and the illumination light L is irradiated on the surface of the inspection object 4 from the positive direction of the Z axis.
  • the electrode 45b is located on the back surface opposite to the side irradiated with the illumination light L.
  • the dead zone regions 61a and 61b in the mask 6a have the same size or allowance as the holes 45a and the electrodes 45b in FIG. 9A, as shown in FIG. 9B. Slightly larger. Regions other than the dead zone regions 61a and 61b in the mask 6a shown in FIG. 9B are used as foreign matter inspection targets. Therefore, when a foreign object adheres to these dead zone regions 61a and 61b, the foreign object cannot be detected.
  • the transmission amount of the illumination light L to the inspection object is selected by selecting the color of the illumination light L according to the surface color of the inspection object 4.
  • the reflection amount (luminance) at the electrode 45b located on the back surface of the inspection object 4, the hole 45a provided in the inspection object 4 and the pedestal hole 5a provided in the pedestal 5 is made substantially zero, or the reflection amount Can be reduced.
  • a threshold value is provided for each pixel of the captured image and binarization is performed with a luminance equal to or higher than the threshold value.
  • the electrode 45b positioned on the back surface of the inspection object 4 In the hole 45a provided in the inspection object 4 and the pedestal hole 5a provided in the pedestal 5, the luminance of the entire region or a part of the region is below a threshold value, and the entire region or a part of the region is recognized (observed). It will be excluded from the target.
  • the illumination light L is incident from the positive direction of the X axis, but the incident illumination light L is reflected at the end of the electrode 45b (the side where the value of X is large), It is conceivable that the luminance is stronger than the other part of the electrode 45b. Therefore, the end of the electrode 45b on the side where the illumination light is incident remains as a recognizable (observable) image even after binarization.
  • the mask 6b used in the foreign substance inspection apparatus 1 of the present embodiment is created based on the binarized captured image 23 shown in FIG. 9C, and has the form shown in FIG. 9D. .
  • the dead zone region 61a for the hole 45a is not required.
  • the dead zone region 61b 'smaller than the actual size of the electrode 45b is sufficient for the electrode 45b. Therefore, as can be seen by comparing the mask 6a for white light in FIG. 9B and the mask 6b of the present embodiment in FIG. 9D, the dead zone area is kept small, and the remaining area, that is, a foreign object inspection target. It is possible to expand the area that becomes.
  • the binarization of the captured image 23 is not necessarily performed, and the binarization may be performed instead of the binarization (n ⁇ 3).
  • the mask 6b used in the image processing of the foreign matter inspection apparatus 1 is created by taking an image of the inspection object 4 that has been sufficiently confirmed that no foreign matter has adhered, and using the captured image. Further, even if the inspection target 4 has the same configuration, when the surface color such as the resist color and the color of the illumination light L are different, the size of the electrode image 23b and the like also changes. It is preferable to create each.
  • FIG. 10 is a flowchart showing a foreign substance inspection process in the foreign substance inspection apparatus 1 of the present embodiment.
  • the color filter in the middle of the manufacturing process described with reference to FIG. In the foreign matter inspection step, first, the inspection object 4 is installed on the base 5 (S11). Then, it is determined whether or not the color resist color that is the surface color of the inspection object 4 is compatible with the color of the illumination light L set in the LED line light sources 3a and 3b. The color of the illumination light L does not match the surface color of the inspection object 4, that is, the color of the applied color resist, such as when the target color resist color is changed due to a change in the production line (S12).
  • the color of the illumination light L is changed so as to match the surface color of the inspection object 4 (S13).
  • the LED line light source 3a is provided with R (red), G (green), and B (blue) LEDs, and changes the color of the illumination light L by changing the brightness of each color LED (adjustment). Light).
  • the surface of the inspection object 4 is irradiated with illumination light (S14), and imaging is performed by the imaging units 2a to 2r.
  • the effective inspection region R1 that is a partial region of the captured image 23 is used for the inspection of foreign matter.
  • the captured image 23 is binarized (S16), and then a mask corresponding to the surface color is applied (S19). Since the mask corresponds to the surface color as described above, if the mask does not match the surface color (S17: No), the mask is changed to one that matches the surface color (S18).
  • the inspection for the presence or absence of a foreign object is performed on the binarized captured image 23 in an area other than the dead zone area by the mask (S20).
  • foreign matter is detected by observing scattered light generated by the foreign matter. If the range of the scattered light (shown in black in FIG. 6) exceeds a threshold value, it is assumed that there is a foreign matter. To be judged.
  • the inspection object 4 is moved from the pedestal 5 (S21), and when there is no foreign object (S22: No), the inspection object 4 enters the next step.
  • the inspection object 4 is subjected to a reprocessing step such as removing the applied color resist or is subjected to a disposal process (S23).
  • a reprocessing step such as removing the applied color resist
  • a disposal process S23.
  • the inspection object 4 is irradiated with the illumination light L having a complementary color relationship with the surface color of the inspection object 4 and the foreign object is inspected based on the captured image.
  • An area for inspecting foreign matter because it is possible to reduce the dead zone area due to scratches on the electrode 45b, the hole 45a provided on the inspection object 4 and the pedestal 5 or the like, or no dead zone area is required. It is possible to increase the inspection accuracy and improve the inspection accuracy.

Abstract

[Problem] To increase the degree of precision to which foreign matter is detected when inspecting for foreign matter adhered to an object for inspection, by means of enlarging an effective inspection area. [Solution] A foreign matter inspection device (1) according to the present invention, which inspects for foreign matter adhered to a surface of an object for inspection (4), wherein said foreign matter inspection device (1) comprises: light source parts (3a, 3b) which irradiate illumination light (L) onto the object for inspection (4), said illumination light (L) being a complementary color to a surface color of the object for inspection (4); imaging parts (2a-2r) which image the object for inspection (4); and a detection part which detects the foreign matter on the basis of images imaged by the imaging parts (2a-2r).

Description

異物検査装置及び異物検査方法Foreign matter inspection apparatus and foreign matter inspection method
　本発明は、液晶カラーフィルタ等、各種基板に付着した異物を検査する異物検査装置、及び、異物検査方法に関する。 The present invention relates to a foreign matter inspection apparatus and a foreign matter inspection method for inspecting foreign matters attached to various substrates such as a liquid crystal color filter.
　従来、半導体製造工程、あるいは、液晶表示装置等のフラットディスプレイの製造工程等では、製品の精度向上等を図ることを目的として、製造工程において、ガラス基板に付着する異物を検出することが行われている。 Conventionally, in a semiconductor manufacturing process or a manufacturing process of a flat display such as a liquid crystal display device, foreign substances adhering to a glass substrate are detected in the manufacturing process for the purpose of improving the accuracy of the product. ing.
　特許文献１には、被検査物体の表面に撮像手段の焦点を合わせて撮像し、撮像された画像から被検査物体の表面の異物を検出し、被検査物体の裏面に撮像手段の焦点を合わせて撮像し、撮像された画像から被検査物体の裏面の異物を検出する異物検出装置が開示されている。特許文献２には、ガラス基板の表面および裏面に付着した異物を高精度で検査しうる異物検査装置が開示されている。そのため、この異物検査装置は、投光位置と受光位置の相対位置を変化させることで、ガラス基板の表面に付着した異物の検出と、ガラス基板の裏面に付着した異物の検出を切り替えることを可能としている。 In Patent Document 1, an imaging unit is focused on the surface of an object to be inspected, foreign matter on the surface of the object to be inspected is detected from the captured image, and the imaging unit is focused on the back surface of the object to be inspected. There has been disclosed a foreign matter detection device that picks up an image and detects foreign matter on the back surface of the object to be inspected from the taken image. Patent Document 2 discloses a foreign matter inspection apparatus capable of inspecting foreign matter attached to the front and back surfaces of a glass substrate with high accuracy. Therefore, this foreign matter inspection device can switch between detection of foreign matter attached to the surface of the glass substrate and detection of foreign matter attached to the back surface of the glass substrate by changing the relative position of the light projecting position and the light receiving position. It is said.
特開２０００－７４８４９号公報JP 2000-74849 A 特開２０１６－１３３３５７号公報JP 2016-133357 A
　液晶表示装置に実装されるカラーフィルタの製造工程では、レジストが塗布された状態で、塗布されたレジストに異物が付着していないか検査を行う必要がある。レジストに異物が付着している場合、その後の工程となる露光において、レジスト面に近接配置されるフォトマスクを破損させる、あるいは、カラーフィルタ自体の品質を損なうことになる。特に、フォトマスクは高価であるため、異物により破損が生じた場合、金銭的な被害は大きいものとなる。 In the manufacturing process of a color filter mounted on a liquid crystal display device, it is necessary to inspect whether or not a foreign substance adheres to the applied resist in a state where the resist is applied. In the case where foreign matters are adhered to the resist, the photomask disposed in the vicinity of the resist surface is damaged or the quality of the color filter itself is deteriorated in the subsequent exposure. In particular, since a photomask is expensive, if damage is caused by foreign matter, the financial damage is significant.
　また、検査対象となる製造途中のカラーフィルタには、ガラス基板の裏面に電極が設けられている、あるいは、ガラス基板に孔が加工されていることがある。また、製造途中のカラーフィルタは台座等に設置された状態で検査されることになるが、台座自体が傷付いていることがある。カラーフィルタの製造工程における検査では、ガラス基板に塗布されたレジスト側（表面）に付着した異物の検査が必要となる。しかしながら、ガラス基板に設けられた電極、孔、あるいは、台座の異物、傷、穴は、表面の検査においても撮像されてしまい、異物との区別が困難となる。そのため、このような電極、孔、台座の傷、穴といった予め分かっている領域については、撮像された画像に対して画像処理を行う際、不感帯領域として扱うマスク処理を行い、異物を検査する領域とはしないことが行われている。 In addition, the color filter that is being manufactured may have an electrode provided on the back surface of the glass substrate or may have holes formed in the glass substrate. In addition, the color filter being manufactured is inspected in a state where it is installed on a pedestal or the like, but the pedestal itself may be damaged. In the inspection in the manufacturing process of the color filter, it is necessary to inspect foreign matters attached to the resist side (surface) applied to the glass substrate. However, the electrodes, holes, or pedestal foreign matter, scratches, and holes provided on the glass substrate are also imaged in the surface inspection, making it difficult to distinguish them from foreign matter. Therefore, for areas that are known in advance, such as electrodes, holes, pedestal scratches, and holes, a mask area that is treated as a dead zone area when image processing is performed on a captured image, and a foreign substance inspection area And what is not done.
　しかしながら、不感帯領域が大きくなると、異物を検査する領域は縮小されることになる。また、不感帯領域に異物が付着した場合であっても、異物が付着していないこととなり、前述するように、フォトマスクの破損、あるいは、製造物の品質を損なうことになる。 However, when the dead zone area becomes large, the area for inspecting foreign matter is reduced. Further, even if foreign matter adheres to the dead zone, no foreign matter has adhered, and as described above, the photomask is damaged or the quality of the product is impaired.
　そのため、本発明に係る異物検査装置は、以下に記載する第１の構成を採用するものである。
　検査対象の表面に付着した異物を検査する異物検査装置であって、
　前記検査対象の表面色と補色関係にある照明光を前記検査対象に照射する光源部と、
　前記検査対象を撮影する撮像部と、
　前記撮像部で撮影された画像に基づいて異物を検出する検出部と、を備える。 Therefore, the foreign substance inspection apparatus according to the present invention employs the first configuration described below.
A foreign matter inspection apparatus for inspecting foreign matter attached to the surface of an inspection object,
A light source unit that irradiates the inspection object with illumination light having a complementary color relationship with the surface color of the inspection object;
An imaging unit for imaging the inspection object;
A detection unit that detects foreign matter based on an image captured by the imaging unit.
　さらに本発明に係る異物検査装置（第２の構成）は、第１の構成において、
　前記検出部は、撮影された画像中、異物の検出対象から除外する不感帯領域を指定するマスクを使用して異物を検出し、
　前記不感帯領域は、前記検査対象の裏面に位置する構造物、あるいは、検査対象に設けられた孔の大きさよりも小さいものである。 Furthermore, the foreign substance inspection apparatus (second configuration) according to the present invention is the first configuration,
The detection unit detects a foreign object using a mask that designates a dead zone area to be excluded from the detection target of the foreign object in the captured image,
The dead zone region is smaller than the size of a structure located on the back surface of the inspection object or a hole provided in the inspection object.
　さらに本発明に係る異物検査装置（第３の構成）は、第２の構成において、
　前記マスクは、前記検査対象の表面色と補色関係にある前記照明光を検査対象に照射して撮影された画像に基づいて形成されたものである。 Furthermore, the foreign substance inspection apparatus (third configuration) according to the present invention is the second configuration,
The mask is formed based on an image photographed by irradiating the inspection object with the illumination light having a complementary color relationship with the surface color of the inspection object.
　さらに本発明に係る異物検査装置（第４の構成）は、第２または第３の構成において、
　前記検出部は、前記検査対象の前記表面色に応じてマスクを変更する。 Furthermore, the foreign matter inspection apparatus (fourth configuration) according to the present invention is the second or third configuration,
The detection unit changes a mask according to the surface color of the inspection target.
　さらに本発明に係る異物検査装置（第５の構成）は、第１から第４の構成の何れか１つにおいて、
　前記光源から照射される前記照明光は、インコヒーレント光である。 Furthermore, the foreign matter inspection apparatus (fifth configuration) according to the present invention includes any one of the first to fourth configurations.
The illumination light emitted from the light source is incoherent light.
　さらに本発明に係る異物検査装置（第６の構成）は、第１から第５の構成の何れか１つにおいて、
　前記検査対象は、表面にカラーレジスト膜が塗布された基板であって、
　前記照明光は、前記カラーレジスト膜の色と補色関係にある。 Furthermore, the foreign matter inspection apparatus (sixth configuration) according to the present invention includes any one of the first to fifth configurations.
The inspection object is a substrate having a surface coated with a color resist film,
The illumination light has a complementary color relationship with the color of the color resist film.
　さらに本発明に係る異物検査装置（第７の構成）は、第１から第６の構成の何れか１つにおいて、
　前記光源部は、前記検査対象の表面色に応じて前記照明光の色を変更する。 Furthermore, in the foreign object inspection device (seventh configuration) according to the present invention, in any one of the first to sixth configurations,
The light source unit changes the color of the illumination light according to the surface color of the inspection target.
　さらに本発明に係る異物検査装置（第８の構成）は、第１から第７の構成の何れか１つにおいて、
　前記撮像部は、前記検査対象で反射した正反射光を受光しない位置であって、前記検査対象の表面に付着した異物の散乱光を受光する位置に配置されている。 Furthermore, the foreign matter inspection apparatus (eighth configuration) according to the present invention includes any one of the first to seventh configurations.
The imaging unit is disposed at a position where the specularly reflected light reflected by the inspection object is not received and a position where the scattered light of the foreign matter attached to the surface of the inspection object is received.
　また本発明に係る異物検査方法（第９の構成）は、
　検査対象の表面に付着した異物を検査する異物検査方法であって、
　前記検査対象の表面色と補色関係にある照明光を前記検査対象に照射し、
　前記検査対象を撮影し、
　前記撮像部で撮影された画像に基づいて異物を検出する。 Moreover, the foreign substance inspection method (9th structure) which concerns on this invention is the following.
A foreign matter inspection method for inspecting foreign matter adhering to a surface to be inspected,
Irradiating the inspection object with illumination light having a complementary color relationship with the surface color of the inspection object;
Photograph the inspection object,
A foreign object is detected based on an image photographed by the imaging unit.
　本発明に係る異物検査装置、異物検査方法によれば、検査対象の表面色と補色関係にある照明光を検査対象に照射し、撮影された画像に基づいて異物の検査を行うことで、検査対象の裏面に位置する電極、検査対象に設けられた孔、台座の傷等のための不感帯領域を小さくする、あるいは、必要としないことが可能となり、異物の検査を行う領域の拡大を図り、検査精度の向上を図ることが可能となる。 According to the foreign matter inspection apparatus and foreign matter inspection method according to the present invention, the inspection object is irradiated with illumination light having a complementary color relationship with the surface color of the inspection target, and the inspection of the foreign matter is performed based on the photographed image. It is possible to reduce or eliminate the dead zone for electrodes located on the back of the object, holes provided in the inspection object, scratches on the base, etc. Inspection accuracy can be improved.
本実施形態における異物検査装置の構成を示す斜視図The perspective view which shows the structure of the foreign material inspection apparatus in this embodiment. 本実施形態における異物検査装置の構成を示す側面図Side view showing the configuration of the foreign matter inspection apparatus in the present embodiment 本実施形態の検査対象となるカラーフィルタの製造工程を示す図The figure which shows the manufacturing process of the color filter used as the test object of this embodiment 本実施形態で使用する照明光の色とカラーレジスト色（検査対象の表面色）の関係を説明するための色相環A hue circle for explaining the relationship between the color of illumination light used in the present embodiment and the color resist color (surface color to be inspected) ミー散乱を説明するための模式図Schematic diagram for explaining Mie scattering ビーズ球を使用して撮影した撮像画像Image taken using a bead sphere 本実施形態の異物検査装置の撮影構成を説明するための側面図Side view for explaining a photographing configuration of the foreign matter inspection apparatus of the present embodiment 本実施形態の撮像画像中、検査対象領域を説明するための模式図Schematic diagram for explaining the inspection target region in the captured image of the present embodiment 本実施形態の画像処理で使用するマスクを説明するための模式図Schematic diagram for explaining a mask used in image processing of the present embodiment 本実施形態の異物検査工程を示すフロー図Flow chart showing foreign substance inspection process of this embodiment
　図１は、本実施形態における異物検査装置１の構成を示す斜視図である。本実施形態の異物検査装置は、台座５の上に設置された検査対象４を照明するＬＥＤ（Light Emitting Diode）線光源３ａ、３ｂ（本発明の「光源部」に相当する）、照明された検査対象４を撮影する撮像部２ａ～２ｒ、そして、撮像部２ａ～２ｒで撮影された画像に対して画像処理を施し、検査対象４の表面に付着した異物を検出する情報処理装置（図示せず、本発明の「検出部」に相当する）を備えて構成されている。 FIG. 1 is a perspective view showing a configuration of a foreign matter inspection apparatus 1 in the present embodiment. The foreign matter inspection apparatus of the present embodiment is illuminated with LED (Light Emitting Diode) line light sources 3a and 3b (corresponding to the “light source part” of the present invention) that illuminate the inspection object 4 installed on the base 5. The imaging units 2a to 2r that shoot the inspection object 4 and the information processing device (not shown) that performs image processing on the images captured by the imaging units 2a to 2r and detects foreign matter attached to the surface of the inspection object 4. And corresponds to the “detection unit” of the present invention.
　本実施形態の検査対象４は、例えば、カラーフィルタの製造工程途中において、表面カラーレジストが塗布された透明基板（ガラス基板等）である。カラーフィルタの製造工程については、後で詳細に説明を行う。なお、異物検査装置１は、検査対象４を製造工程途中のカラーフィルタに限られるものではなく、透明基板を使用する各種分野において使用することが可能である。 The inspection object 4 of the present embodiment is, for example, a transparent substrate (a glass substrate or the like) on which a surface color resist is applied during the color filter manufacturing process. The manufacturing process of the color filter will be described in detail later. The foreign matter inspection apparatus 1 is not limited to the color filter in the middle of the manufacturing process, but can be used in various fields where a transparent substrate is used.
　撮像部２ａ～２ｒは、検査対象４の上方にマトリクス状に配置されている。図１には、撮像部２ｋについて、その撮像範囲Ｐが斜線で示されている。本実施形態では、撮像範囲Ｐの一部を有効検査領域として使用し、残る撮像範囲は異物の検出に使用しない（無効検査領域とする）こととしている。マトリクス状に配置された撮像部２ａ～２ｒは、各有効検査領域の一部が重なるように配置されることで、検査対象４の全面を検査対象とすることが可能となっている。このように、撮像部２ａ～２ｒで撮影することで、検査対象４の全面を検査することが可能となっている。なお、検査対象４の一部領域を撮影し、検査対象４を移動させる、あるいは、撮像部２ａ～２ｒを移動させることで、検査対象４の全面を検査する形態とすることも可能である。また、撮像部２ａ～２ｒの数、配置は、図１に示す形態に限られるものでは無く、検査対象４の大きさ、形状等の各種条件に応じて適宜に決定することが可能である。 The imaging units 2a to 2r are arranged in a matrix above the inspection object 4. In FIG. 1, the imaging range P of the imaging unit 2k is indicated by hatching. In the present embodiment, a part of the imaging range P is used as an effective inspection area, and the remaining imaging range is not used for detection of a foreign object (ineffective inspection area). The imaging units 2a to 2r arranged in a matrix form are arranged so that a part of each effective inspection region overlaps, so that the entire inspection object 4 can be the inspection object. In this way, it is possible to inspect the entire surface of the inspection object 4 by photographing with the imaging units 2a to 2r. It is also possible to take a form in which the entire surface of the inspection object 4 is inspected by photographing a part of the inspection object 4 and moving the inspection object 4 or moving the imaging units 2a to 2r. Further, the number and arrangement of the imaging units 2a to 2r are not limited to the form shown in FIG. 1, and can be appropriately determined according to various conditions such as the size and shape of the inspection object 4.
　光源部としてのＬＥＤ線光源３ａ、３ｂは、検査対象４の横方向から検査対象４の表面に照明光Ｌを照射する。本実施形態の撮像部２ａ～２ｒは、検査対象４の表面に付着した異物を検出するため、異物による散乱光を受光する角度であって、検査対象４による照明光Ｌの正反射光を受光しない角度を向くように配置されている。このような配置により、異物の散乱光を、正反射光に阻害されることなく受光し、異物検出の精度向上を図ることを可能としている。 The LED line light sources 3 a and 3 b as the light source unit irradiate the surface of the inspection object 4 with the illumination light L from the lateral direction of the inspection object 4. The imaging units 2a to 2r of the present embodiment receive the regular reflection light of the illumination light L from the inspection object 4 at an angle at which scattered light from the foreign object is received in order to detect the foreign material attached to the surface of the inspection object 4. It is arranged to face the angle that does not. With such an arrangement, the scattered light of the foreign matter is received without being obstructed by the regular reflection light, and the accuracy of foreign matter detection can be improved.
　光源部には、レーザー光のようなコヒーレント光ではなく、本実施形態のＬＥＤ線光源３ａ、３ｂ、あるいは、蛍光灯等のインコヒーレント光を使用することが好ましい。コヒーレント光を使用した場合、検査対象の裏面に位置する電極等の構造物、あるいは、検査対象に設けられた孔等が実寸で撮影されることになる。一方、照明光にインコヒーレント光を使用するとともに、照明光の色を選択することで、検査対象に対する照明光の透過量を抑え、結果として、検査対象の裏面に位置する電極等構造物、あるいは、検査対象に設けられた孔等が実寸よりも小さく認識（観察）することが可能となり、検査対象領域の拡大を図ることが可能となる。 It is preferable to use incoherent light such as the LED line light sources 3a and 3b of the present embodiment or a fluorescent lamp instead of coherent light such as laser light for the light source unit. When coherent light is used, a structure such as an electrode located on the back surface of the inspection object or a hole provided in the inspection object is photographed in actual size. On the other hand, by using incoherent light as illumination light and selecting the color of illumination light, the amount of illumination light transmitted to the inspection object is suppressed, and as a result, a structure such as an electrode located on the back surface of the inspection object, or The hole or the like provided in the inspection object can be recognized (observed) smaller than the actual size, and the inspection object area can be enlarged.
　図２は、本実施形態における異物検査装置１の構成を示す側面図である。図２は、図１中、撮像部２ａ～２ｆの列における側面図である。ＬＥＤ線光源３ａ、３ｂは、横方向から検査対象４の表面に照明光Ｌを照射する。照明光Ｌは、理想的には、検査対象４の表面と略平行に入射させる、すなわち、検査対象４の表面４に位置する異物にのみ光があたるように入射させることが好ましい。しかしながら、検査対象４、あるいは、台座５の歪みによって、検査対象４の表面が全くの平面とならないことを考慮し、僅かに傾けておく必要が生じる。照明光Ｌの検査対象４の表面に対する傾斜角は、ＸＹ平面と平行状態を０度とした場合、０度～５度の範囲内で検査対象４に向けて傾斜させることが好ましい。さらに好ましくは０度～３度以内とすることが好ましい。なお、図２では、照明光Ｌの傾斜角は、実際よりも大きく誇張して示されている。前述したように、本実施形態の撮像部２ａ～２ｆは、検査対象４の表面に付着した異物による散乱光を受光する角度であって、検査対象４による照明光Ｌの正反射光を受光しない角度を向くように配置されている。 FIG. 2 is a side view showing the configuration of the foreign matter inspection apparatus 1 in the present embodiment. 2 is a side view of the imaging units 2a to 2f in FIG. LED line light source 3a, 3b irradiates the illumination light L to the surface of the test object 4 from the horizontal direction. Ideally, the illumination light L is preferably incident so as to be substantially parallel to the surface of the inspection object 4, that is, incident so that the light strikes only the foreign matter located on the surface 4 of the inspection object 4. However, in consideration of the fact that the surface of the inspection object 4 does not become a flat surface due to the distortion of the inspection object 4 or the pedestal 5, it is necessary to tilt the inspection object 4 slightly. The inclination angle of the illumination light L with respect to the surface of the inspection object 4 is preferably inclined toward the inspection object 4 within a range of 0 to 5 degrees when the state parallel to the XY plane is 0 degree. More preferably, it is within 0 to 3 degrees. In FIG. 2, the inclination angle of the illumination light L is shown exaggerated larger than actual. As described above, the imaging units 2a to 2f of the present embodiment have an angle for receiving scattered light from the foreign matter attached to the surface of the inspection object 4, and do not receive the regular reflection light of the illumination light L from the inspection object 4. It is arranged to face the angle.
　撮像部２ａ～２ｃは、ＬＥＤ線光源３ａの照明光Ｌによる異物での散乱光を受光するべく、ＸＺ平面上、検査対象４の鉛直方向（Ｚ軸方向）と角度Ｅ（１度＜Ｅ＜２０度）だけ傾けて配置されている。一方、撮像部２ｄ～２ｆは、ＬＥＤ線光源３ｂの照明光Ｌによる異物での散乱光を受光するべく、ＸＺ平面上、撮像部２ａ～２ｃとは異なる方向に、角度Ｅだけ傾けて配置されている。このように配置することで、撮像部２ａ～２ｃは、ＬＥＤ線光源３ａによる照明光Ｌにより異物で散乱された散乱光を主として受光し、ＬＥＤ線光源３ａ、３ｂの正反射光の影響を受け難くしている。また、撮像部２ｄ～２ｆは、ＬＥＤ線光源３ｂによる照明光Ｌにより異物で散乱された散乱光を主として受光し、ＬＥＤ線光源３ａ、３ｂの正反射光の影響を受け難くしている。なお、図示していないが、撮像部２ａ～２ｆは、ＹＺ平面内においては鉛直方向を向いた状態となっている。 The imaging units 2a to 2c receive the scattered light from the foreign matter caused by the illumination light L of the LED line light source 3a, and the vertical direction (Z-axis direction) and the angle E (1 degree <E < 20 degrees). On the other hand, the imaging units 2d to 2f are arranged at an angle E in the direction different from the imaging units 2a to 2c on the XZ plane so as to receive the scattered light from the foreign matter by the illumination light L of the LED line light source 3b. ing. By arranging in this way, the imaging units 2a to 2c mainly receive the scattered light scattered by the foreign matter by the illumination light L from the LED line light source 3a, and are affected by the regular reflection light of the LED line light sources 3a and 3b. It is difficult. The imaging units 2d to 2f mainly receive the scattered light scattered by the foreign matter by the illumination light L from the LED line light source 3b, and are hardly affected by the regular reflection light of the LED line light sources 3a and 3b. Although not shown, the imaging units 2a to 2f are in a state of being oriented in the vertical direction in the YZ plane.
　本実施形態では、検査対象４として液晶表示装置に使用されるカラーフィルタとしている。特に、製造工程途中のカラーフィルタについて、表面に付着した異物の検出を行うこととしている。図３は、カラーフィルタの製造工程を示す図である。図３（Ａ）に示すように、ガラス基板等の透明基板４１上にブラックマトリックス４２が形成される。ブラックマトリックス４２の形成については、後で説明するカラーレジスト４３Ｒと同様、露光、現像により行われることになるが、ここではその説明は省略する。図３（Ｂ）に示すように、ブラックマトリックス４２が形成された透明基板４１上に赤色のカラーレジスト４３Ｒが塗布される。本実施形態の異物検査装置１は、このカラーレジスト４３Ｒが塗布された状態を検査対象４としている。 In the present embodiment, the color filter used in the liquid crystal display device is used as the inspection object 4. In particular, for color filters in the middle of the manufacturing process, foreign matter adhering to the surface is detected. FIG. 3 is a diagram illustrating a manufacturing process of a color filter. As shown in FIG. 3A, a black matrix 42 is formed on a transparent substrate 41 such as a glass substrate. The formation of the black matrix 42 is performed by exposure and development as in the case of the color resist 43R described later, but the description thereof is omitted here. As shown in FIG. 3B, a red color resist 43R is applied on a transparent substrate 41 on which a black matrix 42 is formed. In the foreign matter inspection apparatus 1 of the present embodiment, the inspection object 4 is a state where the color resist 43R is applied.
　図３（Ｃ）に示すように、カラーレジスト４３Ｒが塗布された後、フォトマスク４４を上方に配置して露光を行うことになるが、カラーレジスト４３Ｒ上に異物が付着した場合、異物がフォトマスク４４を破損させてしまうことがある。フォトマスク４４は極めて高価であるため、破損による金銭的な被害は大きい。また、異物によるフォトマスク４４の破損に気付かず、カラーフィルタの製造を続けた場合、カラーフィルタ自体に欠損を生じることになる。カラーフィルタの欠損は、例えば、液晶表示装置における表示画像の劣化を生じさせることになる。 As shown in FIG. 3C, after the color resist 43R is applied, the exposure is performed by placing the photomask 44 on the upper side. However, when the foreign matter adheres to the color resist 43R, the foreign matter is exposed to the photo resist. The mask 44 may be damaged. Since the photomask 44 is extremely expensive, the financial damage due to breakage is great. Further, if the manufacture of the color filter is continued without noticing the damage of the photomask 44 due to the foreign matter, the color filter itself will be defective. The loss of the color filter causes, for example, deterioration of a display image in the liquid crystal display device.
　フォトマスク４４に設けられた開口４４ａを介して紫外線を照射し、開口４４ａの位置におけるカラーレジスト４３Ｒを不活性化させる。その後、現像液でカラーレジスト４３Ｒの不要な部分を除去した後、残ったカラーレジスト４３Ｒをベークして硬化させる。図３（Ｄ）は、硬化されたカラーレジスト４３Ｒを示す図である。緑のカラーレジスト４３Ｇについて、図３（Ｂ）、図３（Ｃ）の行程を行うことで、図３（Ｅ）のように、硬化されたカラーレジスト４３Ｇが追加される。そして、青のカラーレジスト４３Ｂについて、図３（Ｂ）、図３（Ｃ）の行程を行うことで、図３（Ｅ）のように、硬化されたカラーレジスト４３Ｂが追加される。本実施形態の異物検査装置１は、緑のカラーレジスト４３Ｇ、青のカラーレジスト４３Ｂが塗布された状態についても検査対象４とし、その表面に付着した異物の検査を実行する。 UV light is irradiated through the opening 44a provided in the photomask 44 to inactivate the color resist 43R at the position of the opening 44a. Thereafter, unnecessary portions of the color resist 43R are removed with a developer, and the remaining color resist 43R is baked and cured. FIG. 3D shows the cured color resist 43R. By performing the steps of FIGS. 3B and 3C for the green color resist 43G, the cured color resist 43G is added as shown in FIG. 3E. Then, the process of FIGS. 3B and 3C is performed on the blue color resist 43B, whereby the cured color resist 43B is added as shown in FIG. 3E. The foreign matter inspection apparatus 1 according to the present embodiment also sets the inspection target 4 in a state where the green color resist 43G and the blue color resist 43B are applied, and executes the inspection of the foreign matter attached to the surface.
　図４は、本実施形態の異物検査装置１で使用する照明光Ｌの色と、検査対象４の表面色となるカラーレジスト色の関係を説明するための色相環である。本実施形態では、２４ブロックに等分割された色相環を使用している。図４（Ａ）は、カラーレジスト４３Ｇの場合であって、矢印で示すようにレジスト色が赤の場合である。色相環では、対向する位置の色が補色となる。ここで、補色とは、ある色光とその補色光を加法混色した場合、白色光を生じる色である。 FIG. 4 is a hue circle for explaining the relationship between the color of the illumination light L used in the foreign matter inspection apparatus 1 of the present embodiment and the color resist color that is the surface color of the inspection object 4. In the present embodiment, a hue circle equally divided into 24 blocks is used. FIG. 4A shows the case of the color resist 43G, in which the resist color is red as indicated by an arrow. In the hue circle, the colors at the opposite positions are complementary colors. Here, the complementary color is a color that generates white light when additive color is mixed between a certain color light and the complementary color light.
　本実施形態では、検査対象４の表面色に応じて、照明光Ｌの色が所定条件を満たすように選択することで、検査対象４の裏面に位置する電極等の構造物、あるいは、検査対象４に設けられた孔、あるいは、台座５の表面の傷等を実寸よりも小さく認識（観察）することを可能としている。従来、照明光Ｌとして白色光等を用いた場合、上述する検査対象４の構造物、孔、台座５の傷については、撮像画像上、実寸で観察されることになる。したがって、これらの構造物、孔、傷については、実寸に応じた不感帯領域を有するマスクを設ける必要がある。不感帯領域では、検査対象４の表面を検査することができなくなる。したがって、不感帯領域に異物が付着した場合には、検査漏れとなることがある。一方、本実施形態では、所定条件を満たす照明光Ｌの色を使用することで、不感帯領域を縮小し、異物を検査する領域の拡大を図ることが可能となっている。 In the present embodiment, by selecting the color of the illumination light L so as to satisfy a predetermined condition according to the surface color of the inspection object 4, a structure such as an electrode located on the back surface of the inspection object 4 or the inspection object It is possible to recognize (observe) holes provided in 4 or scratches on the surface of the pedestal 5 smaller than the actual size. Conventionally, when white light or the like is used as the illumination light L, the structures, holes, and scratches on the pedestal 5 of the inspection object 4 described above are observed in actual size on the captured image. Therefore, it is necessary to provide a mask having a dead zone corresponding to the actual size for these structures, holes, and scratches. In the dead zone region, the surface of the inspection object 4 cannot be inspected. Therefore, if foreign matter adheres to the dead zone area, inspection may be missed. On the other hand, in the present embodiment, by using the color of the illumination light L that satisfies a predetermined condition, it is possible to reduce the dead zone area and enlarge the area for inspecting the foreign matter.
　照明光Ｌの色の条件としては、検査対象４の表面色（本実施形態では、レジスト色）と補色関係にあることとが必要である。ここで、補色関係とは、色相環において、検査対象４の表面色の補色から所定範囲内に中心周波数を有する色としている。例えば、図４（Ａ）に示す、カラーレジスト４３Ｇの場合、レジスト色（赤）に対向して位置する補色の位置から、２４分割された色相環において、所定範囲内、すなわち、その前後、４ブロックの範囲内の色に中心周波数を有する照明光Ｌを使用している。本実施形態では、矢印で示す位置の色に中心周波数を有する照明光Ｌを使用している。また、図４（Ｂ）に示す、カラーレジスト４３Ｇの場合（レジスト色は緑）、図４（Ｃ）に示す、カラーレジスト４３Ｂの場合（レジスト色は青）も同様であって、カラーレジスト色の補色から所定範囲内の色に中心周波数を有する照明光Ｌを使用している。 As a condition of the color of the illumination light L, it is necessary to have a complementary color relationship with the surface color (resist color in the present embodiment) of the inspection object 4. Here, the complementary color relationship is a color having a center frequency within a predetermined range from the complementary color of the surface color of the inspection object 4 in the hue circle. For example, in the case of the color resist 43G shown in FIG. 4A, within a predetermined range, that is, before and after the hue ring divided into 24 from the position of the complementary color located opposite to the resist color (red). Illumination light L having a center frequency for colors within the block range is used. In the present embodiment, the illumination light L having the center frequency for the color at the position indicated by the arrow is used. The same applies to the color resist 43G shown in FIG. 4B (resist color is green) and the color resist 43B shown in FIG. 4C (resist color is blue). Illumination light L having a center frequency in a color within a predetermined range from the complementary color of the above is used.
　図２で説明したように、本実施形態では、撮像部２ａ～２ｒにおいて、異物による散乱光を受光することで、異物を効果的に検出することが可能である。ここで、異物による光の散乱について説明しておく。異物となる微小粒子に光が入射した場合、微少粒子の大きさに応じて散乱の形態は異なることが知られている。微小粒子による散乱は、微少粒子の大きさと光の波長との関係によって大別され、微小粒子の大きさが光の波長の１／１０の場合、レーリー散乱を生じることが、また、微小粒子の大きさがそれ以上の場合、ミー散乱を生じることが知られている。本実施形態で検出対象となる異物は、ガラス基板の破片等であって、ミー散乱を生じる大きさの異物である。 As described with reference to FIG. 2, in this embodiment, the imaging units 2a to 2r can detect the foreign matter effectively by receiving the scattered light from the foreign matter. Here, the scattering of light by a foreign substance will be described. It is known that when light is incident on microparticles that are foreign matters, the form of scattering varies depending on the size of the microparticles. Scattering by microparticles is roughly classified according to the relationship between the size of microparticles and the wavelength of light. When the size of microparticles is 1/10 of the wavelength of light, Rayleigh scattering can occur. It is known that Mie scattering occurs when the size is larger. The foreign object to be detected in the present embodiment is a broken piece of a glass substrate or the like, and is a foreign object having a size that causes Mie scattering.
　図５は、ミー散乱を説明するための模式図であって、球形微小粒子Ｓに照明光Ｌが入射したときの散乱の様子を示す模式図である。図５（Ａ）は、散乱光の様子を示す上面図であり、図５（Ｂ）は、その側面図である。ここでは、検査対象４の表面をＸＹ平面、検査対象の表面に直交する軸をＺ軸、照明光Ｌの進行方向をＸ軸正の方向としている。散乱光は、Ｘ軸の正負方向それぞれに弧を描くように現れる。また、散乱光は、球形微小粒子Ｓの大きさよりも大きく観察されることになるため、散乱光を観察することで、検査対象に付着した異物を効率よく検出することが可能となる。 FIG. 5 is a schematic diagram for explaining Mie scattering, and is a schematic diagram showing a state of scattering when the illumination light L is incident on the spherical microparticle S. FIG. FIG. 5A is a top view showing a state of scattered light, and FIG. 5B is a side view thereof. Here, the surface of the inspection object 4 is the XY plane, the axis orthogonal to the surface of the inspection object is the Z axis, and the traveling direction of the illumination light L is the positive direction of the X axis. Scattered light appears in an arc in each of the positive and negative directions of the X axis. Further, since the scattered light is observed to be larger than the size of the spherical microparticles S, it is possible to efficiently detect the foreign matter attached to the inspection object by observing the scattered light.
　図６は、本実施形態の異物検査装置１を使用して撮像された撮像画像２３（２値化済み）である。ここでは、透明な２つの球形微小粒子Ｓ１、Ｓ２（微少なビーズ球）を検査対象４の表面に付着させて撮像している。破線で示す円は、球形微小粒子Ｓ１、Ｓ２の実際の位置を示しており、実際には撮像画像２３には写っていない。撮像画像２３は、球形微小粒子Ｓ１、Ｓ２に対し、図５と同様、Ｘ軸正の方向に照明光Ｌを入射させて撮影し、画像の２値化された画像である。球形微小粒子Ｓ１、Ｓ２のＸ軸正負の方向には、黒色で示す散乱光が写されている。このように、球形微小粒子Ｓ１、Ｓ２による散乱光は、実際の球形微小粒子Ｓ１、Ｓ２の大きさよりも大きく写されるため、検査対象４の表面に付着した異物の検査には有効である。なお、図５、図６では、異物として球形微小粒子Ｓを使用しているが、これは散乱光の観察が球形形状で最も困難であることを理由としている。実際の異物は、ガラス破片等、球形とは異なる形状が一般的であり、そのような形状において散乱光は顕著に現れることになり、その観察は容易である。 FIG. 6 shows a captured image 23 (binarized) captured using the foreign matter inspection apparatus 1 of the present embodiment. Here, two transparent spherical fine particles S1 and S2 (small bead spheres) are attached to the surface of the inspection object 4 and imaged. Circles indicated by broken lines indicate actual positions of the spherical microparticles S <b> 1 and S <b> 2 and are not actually shown in the captured image 23. The captured image 23 is a binarized image obtained by photographing the spherical minute particles S1 and S2 with the illumination light L incident in the positive X-axis direction, as in FIG. Scattered light shown in black is captured in the positive and negative X-axis directions of the spherical microparticles S1 and S2. As described above, the scattered light from the spherical microparticles S1 and S2 is projected larger than the actual size of the spherical microparticles S1 and S2, and thus is effective for the inspection of the foreign matter attached to the surface of the inspection object 4. In FIG. 5 and FIG. 6, spherical microparticles S are used as foreign substances, which is because observation of scattered light is most difficult in a spherical shape. An actual foreign object generally has a shape different from a spherical shape such as a glass piece, and scattered light appears remarkably in such a shape, and its observation is easy.
　図７は、本実施形態の異物検査装置１の撮影構成を説明するための側面図である。ここでは、図１、図２で説明した構成中、１の撮像部２ａを例に取ってその撮像構成を説明する。本実施形態では、検査対象４の表面を、Ｙ軸方向に延在するＬＥＤ線光源３ａで照明し、検査対象４に付着する異物で散乱した散乱光を撮像部２ａで撮像することとしている。ここでは、異物のサンプルとして、Ｘ軸方向に等間隔で６個の球形微小粒子Ｓ１～Ｓ６を並べている。これら球形微小粒子Ｓ１～Ｓ６は、撮像部２ａの撮像範囲Ｔに入るように配置されている。図７中、照明光Ｌは、検査対象４の表面と略平行に入射させているが、図２で説明したように、僅かに検査対象４側に向けて傾斜させてもよい。 FIG. 7 is a side view for explaining a photographing configuration of the foreign matter inspection apparatus 1 of the present embodiment. Here, in the configuration described with reference to FIGS. 1 and 2, the imaging configuration will be described using one imaging unit 2 a as an example. In the present embodiment, the surface of the inspection object 4 is illuminated with the LED line light source 3a extending in the Y-axis direction, and the scattered light scattered by the foreign matter attached to the inspection object 4 is imaged by the imaging unit 2a. Here, six spherical microparticles S1 to S6 are arranged at equal intervals in the X-axis direction as a sample of foreign matter. These spherical fine particles S1 to S6 are arranged so as to fall within the imaging range T of the imaging unit 2a. In FIG. 7, the illumination light L is incident substantially parallel to the surface of the inspection object 4, but may be slightly inclined toward the inspection object 4 as described with reference to FIG.
　本実施形態では、異物で生じた散乱光を鮮鋭に撮影することが、異物の発見において好ましい。球形微小粒子Ｓ１～Ｓ６の散乱光をできるだけ多く受光するには、球形微小粒子Ｓ１～Ｓ６において、照明光Ｌの入射側とは反対側に生じる散乱光について、その受光量を多くするべく、撮像部２ａの角度Ｅを大きくとることが好ましい。しかしながら、角度Ｅを大きくした場合、散乱光のみならず、照明光Ｌの正反射光が入射することになり、正反射光で散乱光が阻害されてしまうことになる。そのため、本実施形態では、撮像部２ａの角度ＥをＬＥＤ線光源３ａからの照明光Ｌによる正反射光が入射しない程度の角度（１度～２０度の範囲）としている。 In this embodiment, it is preferable to detect the scattered light generated by the foreign object sharply in finding the foreign object. In order to receive as much scattered light as possible from the spherical microparticles S1 to S6, in order to increase the amount of received light of the scattered light generated on the side opposite to the incident side of the illumination light L in the spherical microparticles S1 to S6. It is preferable to increase the angle E of the portion 2a. However, when the angle E is increased, not only the scattered light but also the regular reflected light of the illumination light L is incident, and the scattered light is inhibited by the regular reflected light. For this reason, in the present embodiment, the angle E of the imaging unit 2a is set to an angle (in the range of 1 to 20 degrees) such that the regular reflection light by the illumination light L from the LED line light source 3a does not enter.
　また、光学系２２の光軸が撮像面２１と垂直な関係にある一般的な撮像部２ａを使用した場合、撮像部２ａの撮像範囲Ｔ中、Ｘ軸正の方向に従って、散乱光の受光量は小さくなる。そのため、本実施形態では、撮像範囲Ｔを全て使用するのではなく、ＬＥＤ線光源３ａ側に位置する有効検査領域Ｒ１を異物の検出対象として使用する。そして、ＬＥＤ線光源３ａから離れて位置する無効検査領域Ｒ２は異物の検出対象として使用しないこととしている。したがって、図１、図２で説明したように複数の撮像部２ａ～２ｒを使用して検査対象４の全面を検査する場合、撮像部２ａ～２は、有効検査領域Ｒ１の一部が重なるように配置される。 Further, when a general imaging unit 2a in which the optical axis of the optical system 22 is perpendicular to the imaging surface 21 is used, the amount of scattered light received according to the positive X-axis direction in the imaging range T of the imaging unit 2a. Becomes smaller. For this reason, in the present embodiment, the entire imaging range T is not used, but the effective inspection region R1 located on the LED line light source 3a side is used as a foreign object detection target. The invalid inspection region R2 located away from the LED line light source 3a is not used as a foreign object detection target. Accordingly, when the entire surface of the inspection object 4 is inspected using the plurality of imaging units 2a to 2r as described with reference to FIGS. 1 and 2, the imaging units 2a to 2 are arranged such that a part of the effective inspection region R1 overlaps. Placed in.
　図８は、本実施形態の撮像画像２３中、有効検査領域Ｒ１を説明するための模式図である。図７で説明したように、本実施形態では、撮像範囲Ｔ中、ＬＥＤ線光源３ａから照明光Ｌが入射する側に位置する領域を、異物の検査に使用する有効検査領域Ｒ１としている。また、残る領域を異物の検査に使用しない無効検査領域Ｒ２としている。図８を見て分かるように、光学系２２の光軸が撮像面２１に直交する撮像部２ａを使用した場合、撮像画像２３における光軸Ｃ２の位置は、撮像画像２３の中心に位置する。一方、有効検査領域Ｒ１の画像中心Ｃ１は、撮像画像２３から無効検査領域Ｒ２が切り取られるため、照明光Ｌが入射する側に偏移している。 FIG. 8 is a schematic diagram for explaining the effective inspection region R1 in the captured image 23 of the present embodiment. As described with reference to FIG. 7, in the present embodiment, an area located on the side where the illumination light L is incident from the LED line light source 3 a in the imaging range T is set as an effective inspection area R <b> 1 used for the inspection of foreign matter. Further, the remaining area is set as an invalid inspection area R2 that is not used for the inspection of foreign matter. As can be seen from FIG. 8, when the imaging unit 2 a in which the optical axis of the optical system 22 is orthogonal to the imaging surface 21 is used, the position of the optical axis C <b> 2 in the captured image 23 is located at the center of the captured image 23. On the other hand, the image center C1 of the effective inspection region R1 is shifted to the side on which the illumination light L is incident because the invalid inspection region R2 is cut out from the captured image 23.
　図９は、本実施形態の画像処理で使用するマスクを説明するための模式図である。マスクとは、撮像画像２３中、異物の検査に使用しない不感帯領域を指定するために使用される。不感帯領域は、検査対象４中、予め分かっている構造物、孔、傷等の位置に割り当てられ、これらを異物として誤検出しないことを目的としている。本実施形態では、照明光Ｌにインコヒーレント光を使用し、その色を選定することで、特に、検査対象４の裏面に位置する電極等の構造物、検査対象４に設けられた孔、台座５の表面にある傷等を、実寸よりも小さく認識（観察）されることを可能としている。したがって、マスク中の不感帯領域を縮小する、あるいは、不感帯領域を設けなくてもよいこととし、不感帯領域以外の領域、すなわち、異物の検査対象となる領域の拡大を図ることが可能となる。 FIG. 9 is a schematic diagram for explaining a mask used in image processing according to the present embodiment. The mask is used for designating a dead zone area that is not used for the inspection of foreign matter in the captured image 23. The dead zone region is assigned to positions of structures, holes, scratches, and the like that are known in advance in the inspection object 4, and is intended to prevent erroneous detection of these as foreign matters. In the present embodiment, incoherent light is used as the illumination light L and the color thereof is selected, so that in particular, structures such as electrodes located on the back surface of the inspection object 4, holes provided in the inspection object 4, pedestal 5 can be recognized (observed) smaller than the actual size. Therefore, it is possible to reduce the dead zone area in the mask or not to provide the dead zone area, and it is possible to enlarge the area other than the dead zone area, that is, the area to be inspected for foreign matter.
　図９（Ａ）は、検査対象４の裏面に設けた電極４５ｂ、検査対象４を貫通する孔４５ａを模式的に示した上面図、及び、孔４５ａの位置における断面図である。図９で示す座標系は、図１、図２と同様であって、照明光Ｌは、Ｚ軸正の方向から検査対象４の表面に照射される。電極４５ｂは、照明光Ｌが照射される側とは反対の裏面に位置している。 FIG. 9A is a top view schematically showing the electrode 45b provided on the back surface of the inspection object 4, the hole 45a penetrating the inspection object 4, and a cross-sectional view at the position of the hole 45a. The coordinate system shown in FIG. 9 is the same as that in FIGS. 1 and 2, and the illumination light L is irradiated on the surface of the inspection object 4 from the positive direction of the Z axis. The electrode 45b is located on the back surface opposite to the side irradiated with the illumination light L.
　照明光Ｌに白色光を使用して撮影した場合、孔４５ａ、電極４５ｂは、実寸で観察されることになる。そのため、白色光を使用した場合のマスク６ａにおける不感帯領域６１ａ、６１ｂは、図９（Ｂ）に示すように、図９（Ａ）の孔４５ａ、電極４５ｂと同じ大きさ、あるいは、余裕をみて僅かに大きく設けられる。図９（Ｂ）のマスク６ａ中、不感帯領域６１ａ、６１ｂ以外の領域が異物の検査対象として使用される。したがって、これら不感帯領域６１ａ、６１ｂに異物が付着していた場合、当該異物は検出できないことになる。 When photographing using white light as the illumination light L, the hole 45a and the electrode 45b are observed in actual size. Therefore, when the white light is used, the dead zone regions 61a and 61b in the mask 6a have the same size or allowance as the holes 45a and the electrodes 45b in FIG. 9A, as shown in FIG. 9B. Slightly larger. Regions other than the dead zone regions 61a and 61b in the mask 6a shown in FIG. 9B are used as foreign matter inspection targets. Therefore, when a foreign object adheres to these dead zone regions 61a and 61b, the foreign object cannot be detected.
　一方、本実施形態の異物検査装置１では、図４でも説明したように、照明光Ｌの色を検査対象４の表面色に応じて選択することで、検査対象への照明光Ｌの透過量を減少させ、検査対象４の裏面に位置する電極４５ｂ、検査対象４に設けられた孔４５ａ、台座５に設けられた台座孔５ａにおける反射量（輝度）を略０とする、あるいは、反射量を低下させることが可能となる。本実施形態では、撮像画像の各画素に対して閾値を設け、閾値以上の輝度で２値化を行っているが、２値化を行うことで、検査対象４の裏面に位置する電極４５ｂ、検査対象４に設けられた孔４５ａ、台座５に設けられた台座孔５ａは、その全領域、あるいは、一部領域の輝度が閾値以下となり、全領域、あるいは、一部領域が認識（観察）対象から外れることになる。例えば、図９（Ａ）では、Ｘ軸正の方向から照明光Ｌが入射することになるが、入射する照明光Ｌが電極４５ｂの端部（Ｘの値が大きい側）で反射を起こし、電極４５ｂの他の部分よりも輝度が強くなることが考えられる。そのため、電極４５ｂの照明光が入射する側の端部では、２値化後においても、認識（観察）可能な画像として残ってしまう。 On the other hand, in the foreign substance inspection apparatus 1 according to the present embodiment, as described with reference to FIG. 4, the transmission amount of the illumination light L to the inspection object is selected by selecting the color of the illumination light L according to the surface color of the inspection object 4. The reflection amount (luminance) at the electrode 45b located on the back surface of the inspection object 4, the hole 45a provided in the inspection object 4 and the pedestal hole 5a provided in the pedestal 5 is made substantially zero, or the reflection amount Can be reduced. In the present embodiment, a threshold value is provided for each pixel of the captured image and binarization is performed with a luminance equal to or higher than the threshold value. However, by performing binarization, the electrode 45b positioned on the back surface of the inspection object 4, In the hole 45a provided in the inspection object 4 and the pedestal hole 5a provided in the pedestal 5, the luminance of the entire region or a part of the region is below a threshold value, and the entire region or a part of the region is recognized (observed). It will be excluded from the target. For example, in FIG. 9A, the illumination light L is incident from the positive direction of the X axis, but the incident illumination light L is reflected at the end of the electrode 45b (the side where the value of X is large), It is conceivable that the luminance is stronger than the other part of the electrode 45b. Therefore, the end of the electrode 45b on the side where the illumination light is incident remains as a recognizable (observable) image even after binarization.
　本実施形態の異物検査装置１で使用するマスク６ｂは、図９（Ｃ）に示す２値化された撮像画像２３に基づいて作成されることになり、図９（Ｄ）に示す形態となる。マスク６ｂでは、図９（Ｃ）に示されるように、撮像画像２３において孔４５ａが消去されているため、孔４５ａに対する不感帯領域６１ａを必要としない。また、電極４５ｂについては、電極４５ｂの実寸よりも小さい不感帯領域６１ｂ’で済むことになる。よって、図９（Ｂ）の白色光におけるマスク６ａと、図９（Ｄ）の本実施形態のマスク６ｂを比較して分かるように、不感帯領域を小さく抑え、残る領域、すなわち、異物の検査対象となる領域拡大を図ることが可能となっている。なお、異物の検出を行う際の画像処理として、撮像画像２３に対する２値化は必ずしも行う必要はなく、２値化に代えてｎ値化（ｎ≧３）とすることとしてもよい。 The mask 6b used in the foreign substance inspection apparatus 1 of the present embodiment is created based on the binarized captured image 23 shown in FIG. 9C, and has the form shown in FIG. 9D. . In the mask 6b, as shown in FIG. 9C, since the hole 45a is erased in the captured image 23, the dead zone region 61a for the hole 45a is not required. Further, the dead zone region 61b 'smaller than the actual size of the electrode 45b is sufficient for the electrode 45b. Therefore, as can be seen by comparing the mask 6a for white light in FIG. 9B and the mask 6b of the present embodiment in FIG. 9D, the dead zone area is kept small, and the remaining area, that is, a foreign object inspection target. It is possible to expand the area that becomes. It should be noted that as the image processing when detecting the foreign matter, the binarization of the captured image 23 is not necessarily performed, and the binarization may be performed instead of the binarization (n ≧ 3).
　異物検査装置１の画像処理で使用するマスク６ｂは、異物が付着していないことを十分に確認した検査対象４を撮影し、その撮像画像を使用して作成される。また、同じ構成の検査対象４であっても、レジスト色等の表面色、及び、照明光Ｌの色が異なる場合には、電極像２３ｂ等の大きさも変化するため、検査対象４の表面色毎に作成されることが好ましい。 The mask 6b used in the image processing of the foreign matter inspection apparatus 1 is created by taking an image of the inspection object 4 that has been sufficiently confirmed that no foreign matter has adhered, and using the captured image. Further, even if the inspection target 4 has the same configuration, when the surface color such as the resist color and the color of the illumination light L are different, the size of the electrode image 23b and the like also changes. It is preferable to create each.
　図１０は、本実施形態の異物検査装置１における異物検査工程を示すフロー図である。本実施形態では、図３で説明した製造工程途中のカラーフィルタを検査対象４としている。異物検査工程では、まず、台座５に検査対象４が設置される（Ｓ１１）。そして、検査対象４の表面色であるカラーレジスト色が、ＬＥＤ線光源３ａ、３ｂに設定されている照明光Ｌの色と適合しているか否かが判定される。製造ラインの変更などに伴い、対象となるカラーレジスト色が変更された場合等、照明光Ｌの色が検査対象４の表面色、すなわち、塗布されているカラーレジストの色に適合しない場合（Ｓ１２：Ｎｏ）には、検査対象４の表面色に適合するように、照明光Ｌの色を変更する（Ｓ１３）。ＬＥＤ線光源３ａには、Ｒ（赤）、Ｇ（緑）、Ｂ（青）のＬＥＤが設けられており、各色ＬＥＤの明るさを変化させることで、照明光Ｌの色を変更する（調光する）ことが可能である。 FIG. 10 is a flowchart showing a foreign substance inspection process in the foreign substance inspection apparatus 1 of the present embodiment. In the present embodiment, the color filter in the middle of the manufacturing process described with reference to FIG. In the foreign matter inspection step, first, the inspection object 4 is installed on the base 5 (S11). Then, it is determined whether or not the color resist color that is the surface color of the inspection object 4 is compatible with the color of the illumination light L set in the LED line light sources 3a and 3b. The color of the illumination light L does not match the surface color of the inspection object 4, that is, the color of the applied color resist, such as when the target color resist color is changed due to a change in the production line (S12). : No), the color of the illumination light L is changed so as to match the surface color of the inspection object 4 (S13). The LED line light source 3a is provided with R (red), G (green), and B (blue) LEDs, and changes the color of the illumination light L by changing the brightness of each color LED (adjustment). Light).
　そして、検査対象４の表面に照明光を照射し（Ｓ１４）、撮像部２ａ～２ｒで撮像を行う。なお、本実施形態では、撮像画像２３の一部領域である有効検査領域Ｒ１を、異物の検査に使用する。撮像画像２３は、２値化された（Ｓ１６）後、表面色に対応したマスクが施される（Ｓ１９）。なお、前述したようにマスクは表面色に対応しているため、マスクが表面色に適合していない場合（Ｓ１７：Ｎｏ）、マスクは表面色に適合するものに変更される（Ｓ１８）。 Then, the surface of the inspection object 4 is irradiated with illumination light (S14), and imaging is performed by the imaging units 2a to 2r. In the present embodiment, the effective inspection region R1 that is a partial region of the captured image 23 is used for the inspection of foreign matter. The captured image 23 is binarized (S16), and then a mask corresponding to the surface color is applied (S19). Since the mask corresponds to the surface color as described above, if the mask does not match the surface color (S17: No), the mask is changed to one that matches the surface color (S18).
　異物の有無の検査は、２値化された撮像画像２３に対し、マスクによる不感帯領域以外の領域に対して行われる（Ｓ２０）。図６で説明したように、異物の検出は、異物で生じる散乱光を観察することで行われるが、この散乱光の範囲（図６の黒色で示す部分）が閾値を超える場合、異物ありとして判断される。検査が行われた後、検査対象４は、台座５から移動され（Ｓ２１）、異物無しの場合（Ｓ２２：Ｎｏ）は、検査対象４は次の工程に入る。一方、異物有りの場合（Ｓ２２：Ｙｅｓ）には、検査対象４は、塗布されたカラーレジストを取り除く等の再処理工程が行われる、あるいは、廃棄処理の対象となる（Ｓ２３）。なお、異物の有無の検査は、上述する形態以外に、各種形態で行うことが可能である。 The inspection for the presence or absence of a foreign object is performed on the binarized captured image 23 in an area other than the dead zone area by the mask (S20). As described with reference to FIG. 6, foreign matter is detected by observing scattered light generated by the foreign matter. If the range of the scattered light (shown in black in FIG. 6) exceeds a threshold value, it is assumed that there is a foreign matter. To be judged. After the inspection is performed, the inspection object 4 is moved from the pedestal 5 (S21), and when there is no foreign object (S22: No), the inspection object 4 enters the next step. On the other hand, when there is a foreign substance (S22: Yes), the inspection object 4 is subjected to a reprocessing step such as removing the applied color resist or is subjected to a disposal process (S23). The inspection for the presence or absence of foreign matters can be performed in various forms other than the above-described forms.
　このように、本実施形態では、検査対象４の表面色と補色関係にある照明光Ｌを検査対象４に照射し、撮影された画像に基づいて異物の検査を行うことで、検査対象４の裏面に位置する電極４５ｂ、検査対象４に設けられた孔４５ａ、台座５の傷等のための不感帯領域を小さくする、あるいは、不感帯領域を必要としないことが可能となり、異物の検査を行う領域の拡大を図り、検査精度の向上を図ることが可能となる。 As described above, in this embodiment, the inspection object 4 is irradiated with the illumination light L having a complementary color relationship with the surface color of the inspection object 4 and the foreign object is inspected based on the captured image. An area for inspecting foreign matter, because it is possible to reduce the dead zone area due to scratches on the electrode 45b, the hole 45a provided on the inspection object 4 and the pedestal 5 or the like, or no dead zone area is required. It is possible to increase the inspection accuracy and improve the inspection accuracy.
　なお、本発明はこれらの実施形態のみに限られるものではなく、それぞれの実施形態の構成を適宜組み合わせて構成した実施形態も本発明の範疇となるものである。 Note that the present invention is not limited to these embodiments, and embodiments configured by appropriately combining the configurations of the respective embodiments also fall within the scope of the present invention.
１：異物検査装置
２ａ～２ｒ：撮像部
３ａ、３ｂ：ＬＥＤ線光源
４：検査対象
５：台座
６ａ、６ｂ：マスク
２１：撮像面
２２：光学系
２３：撮像画像
２３ｂ：電極像
４１：透明基板
４２：ブラックマトリックス
４３Ｒ、４３Ｇ、４３Ｂ：カラーレジスト
４４：フォトマスク
４４ａ：開口
４５ａ：孔
４５ｂ：電極
６１ａ、６１ｂ、６１ｂ’：不感帯領域
Ｃ１：画像中心
Ｃ２：光軸
Ｅ：角度
Ｌ：照明光
Ｐ：撮像範囲
Ｒ１：有効検査領域
Ｒ２：無効検査領域
Ｓ（Ｓ１～Ｓ６）：球形微小粒子
Ｔ：撮像範囲 1: foreign matter inspection devices 2a to 2r: imaging units 3a, 3b: LED line light source 4: inspection target 5: pedestal 6a, 6b: mask 21: imaging surface 22: optical system 23: captured image 23b: electrode image 41: transparent substrate 42: Black matrix 43R, 43G, 43B: Color resist 44: Photomask 44a: Opening 45a: Hole 45b: Electrodes 61a, 61b, 61b ′: Dead zone C1: Image center C2: Optical axis E: Angle L: Illumination light P : Imaging range R1: Effective inspection region R2: Invalid inspection region S (S1 to S6): Spherical microparticle T: Imaging range

Claims (9)

  1. 　検査対象の表面に付着した異物を検査する異物検査装置であって、
    　前記検査対象の表面色と補色関係にある照明光を前記検査対象に照射する光源部と、
    　前記検査対象を撮影する撮像部と、
    　前記撮像部で撮影された画像に基づいて異物を検出する検出部と、を備える
    　異物検査装置。     A foreign matter inspection apparatus for inspecting foreign matter attached to the surface of an inspection object,
    A light source unit that irradiates the inspection object with illumination light having a complementary color relationship with the surface color of the inspection object;
    An imaging unit for imaging the inspection object;
    A foreign matter inspection apparatus comprising: a detection unit that detects foreign matter based on an image photographed by the imaging unit.
  2. 　前記検出部は、撮影された画像中、異物の検出対象から除外する不感帯領域を指定するマスクを使用して異物を検出し、
    　前記不感帯領域は、前記検査対象の裏面に位置する構造物、あるいは、検査対象に設けられた孔の大きさよりも小さい
    　請求項１に記載の異物検査装置。     The detection unit detects a foreign object using a mask that designates a dead zone area to be excluded from the detection target of the foreign object in the captured image,
    The foreign substance inspection device according to claim 1, wherein the dead zone region is smaller than a structure located on a back surface of the inspection target or a size of a hole provided in the inspection target.
  3. 　前記マスクは、前記検査対象の表面色と補色関係にある前記照明光を検査対象に照射して撮影された画像に基づいて形成されたものである
    　請求項２に記載の異物検査装置。     The foreign matter inspection apparatus according to claim 2, wherein the mask is formed based on an image photographed by irradiating the inspection target with the illumination light having a complementary color relationship with the surface color of the inspection target.
  4. 　前記検出部は、前記検査対象の前記表面色に応じてマスクを変更する
    　請求項２に記載の異物検査装置。     The foreign matter inspection apparatus according to claim 2, wherein the detection unit changes a mask according to the surface color of the inspection target.
  5. 　前記光源から照射される前記照明光は、インコヒーレント光である
    　請求項１に記載の異物検査装置。     The foreign matter inspection apparatus according to claim 1, wherein the illumination light emitted from the light source is incoherent light.
  6. 　前記検査対象は、表面にカラーレジスト膜が塗布された基板であって、
    　前記照明光は、前記カラーレジスト膜の色と補色関係にある
    　請求項１に記載の異物検査装置。     The inspection object is a substrate having a surface coated with a color resist film,
    The foreign matter inspection apparatus according to claim 1, wherein the illumination light has a complementary color relationship with a color of the color resist film.
  7. 　前記光源部は、前記検査対象の表面色に応じて前記照明光の色を変更する
    　請求項１に記載の異物検査装置。     The foreign matter inspection apparatus according to claim 1, wherein the light source unit changes a color of the illumination light according to a surface color of the inspection target.
  8. 　前記撮像部は、前記検査対象で反射した正反射光を受光しない位置であって、前記検査対象の表面に付着した異物の散乱光を受光する位置に配置されている
    　請求項１に記載の異物検出装置。     The foreign object according to claim 1, wherein the imaging unit is a position that does not receive the specularly reflected light reflected by the inspection object, and is a position that receives the scattered light of the foreign object attached to the surface of the inspection object. Detection device.
  9. 　検査対象の表面に付着した異物を検査する異物検査方法であって、
    　前記検査対象の表面色と補色関係にある照明光を前記検査対象に照射し、
    　前記検査対象を撮影し、
    　前記撮像部で撮影された画像に基づいて異物を検出する
    　異物検査方法。     A foreign matter inspection method for inspecting foreign matter adhering to a surface to be inspected,
    Irradiating the inspection object with illumination light having a complementary color relationship with the surface color of the inspection object;
    Photograph the inspection object,
    A foreign matter inspection method for detecting foreign matter based on an image photographed by the imaging unit.
PCT/JP2018/022470 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method WO2019239501A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2020524994A JP6980241B2 (en) 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method
PCT/JP2018/022470 WO2019239501A1 (en) 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method
CN201880094385.9A CN112236671A (en) 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method
TW108119929A TWI721447B (en) 2018-06-12 2019-06-10 Foreign body inspection device and foreign body inspection method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2018/022470 WO2019239501A1 (en) 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method

Publications (1)

Publication Number Publication Date
WO2019239501A1 true WO2019239501A1 (en) 2019-12-19

Family

ID=68842040

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2018/022470 WO2019239501A1 (en) 2018-06-12 2018-06-12 Foreign matter inspection device and foreign matter inspection method

Country Status (4)

Country Link
JP (1) JP6980241B2 (en)
CN (1) CN112236671A (en)
TW (1) TWI721447B (en)
WO (1) WO2019239501A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0426844A (en) * 1990-05-22 1992-01-30 Dainippon Printing Co Ltd Foreign matter inspecting method
JP2007040862A (en) * 2005-08-04 2007-02-15 Dainippon Printing Co Ltd Foreign matter inspection device and method
JP2007085964A (en) * 2005-09-26 2007-04-05 Toshiba Matsushita Display Technology Co Ltd System and method for measuring transparent film
JP2012002661A (en) * 2010-06-16 2012-01-05 Io Giken Co Ltd Appearance inspection device

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1056652A (en) * 1964-04-14 1967-01-25 Int Standard Electric Corp Flaw detection apparatus
JP2004219108A (en) * 2003-01-09 2004-08-05 Dainippon Printing Co Ltd Method and apparatus for inspecting irregularities in film thickness of colored film
JP5403852B2 (en) * 2005-08-12 2014-01-29 株式会社荏原製作所 Detection device and inspection device
WO2011049190A1 (en) * 2009-10-24 2011-04-28 株式会社Djtech Visual testing device and printed solder testing device
US8501503B2 (en) * 2011-04-28 2013-08-06 Nanda Technologies Gmbh Methods of inspecting and manufacturing semiconductor wafers
JP2014077685A (en) * 2012-10-10 2014-05-01 Ntn Corp Device and method for detecting pattern defects
JP6500518B2 (en) * 2015-03-10 2019-04-17 オムロン株式会社 Sheet inspection device
JP2017156659A (en) * 2016-03-04 2017-09-07 凸版印刷株式会社 Defect inspection device and defect inspection method for color filter

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0426844A (en) * 1990-05-22 1992-01-30 Dainippon Printing Co Ltd Foreign matter inspecting method
JP2007040862A (en) * 2005-08-04 2007-02-15 Dainippon Printing Co Ltd Foreign matter inspection device and method
JP2007085964A (en) * 2005-09-26 2007-04-05 Toshiba Matsushita Display Technology Co Ltd System and method for measuring transparent film
JP2012002661A (en) * 2010-06-16 2012-01-05 Io Giken Co Ltd Appearance inspection device

Also Published As

Publication number Publication date
TW202004557A (en) 2020-01-16
TWI721447B (en) 2021-03-11
JP6980241B2 (en) 2021-12-15
CN112236671A (en) 2021-01-15
JPWO2019239501A1 (en) 2021-03-18

Similar Documents

Publication Publication Date Title
JP5909751B2 (en) Flat glass foreign matter inspection apparatus and inspection method
TWI626438B (en) Inspection apparatus and article manufacturing method
TW201531695A (en) Automatic appearance inspection device
KR102066520B1 (en) Epitaxial wafer backside inspection apparatus and epitaxial wafer backside inspection method using the same
KR20090028505A (en) End section inspecting apparatus
JP2004037248A (en) Inspection device and inspection method for through hole
KR101203210B1 (en) Apparatus for inspecting defects
KR101320183B1 (en) Method for inspecting pattern defect, apparatus for inspecting pattern defect, method of manufacturing photomask, and method of manufacturing substrate for display device
JP7125576B2 (en) Foreign matter inspection device and foreign matter inspection method
JP4151306B2 (en) Inspection method of inspection object
JP7011348B2 (en) Foreign matter inspection device and foreign matter inspection method
WO2019239501A1 (en) Foreign matter inspection device and foreign matter inspection method
JP2009236760A (en) Image detection device and inspection apparatus
JP2008039444A (en) Method and apparatus for inspecting foreign matter
JP2014077685A (en) Device and method for detecting pattern defects
JP2007147547A (en) Density unevenness testing apparatus
JPH09189665A (en) Dark field illumination device used for defect inspecting device
JP3149336B2 (en) Optical member inspection device
JP2012058029A (en) Periodic pattern inspection device
JP2006284217A (en) Visual inspection method and visual inspection device for color filter
JP6086277B2 (en) Pattern inspection apparatus and illumination optical system used therefor
JP2008111746A (en) Substrate inspection device and substrate inspection method
JP5685833B2 (en) Periodic pattern inspection method
JP2004146108A (en) Phosphor inspection method and device
KR20210051766A (en) Wafer Surface Defect Inspection Equipment

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18922717

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2020524994

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18922717

Country of ref document: EP

Kind code of ref document: A1