JP2007040862A - Foreign matter inspection device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foreign matter inspection device allowing inspection not to affect an unexposed colored layer, and not limiting greatly a layout and equipment constitution in a production line, in the foreign matter inspection device for detecting a foreign matter in the unexposed colored layer on a substrate for forming a color filter, before exposed by an exposure unit for carrying out proximity exposure. <P>SOLUTION: This foreign matter inspection device includes a mounting block for mounting the substrate arranged with the unexposed colored layer as an inspected substrate, under the condition where the inspected substrate is mounted in a horizontal state, one or more of laser beam irradiation parts for irradiating a desired inspection area of the unexposed colored layer, in a side face side of the inspected substrate, at an inclined angle with a laser beam, one or more of photographing means arranged in an upper side in a direction orthogonal to an unexposed colored layer forming face of the inspected substrate, for photographing scattered lights in the foreign matter of the laser beams emitted from the laser beam irradiation parts, and for acquiring photographed image data by the scattered lights over the whole inspection area, and an image processing part for image-processing the respective photographed image data acquired by the respective photographing means, and for extracting the foreign matter in the unexposed colored layer over the whole inspection area. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an unexposed colored layer disposed on one side of a substrate for forming a color filter for a display device, before transferring and exposing the pattern of the transfer mask by proximity exposure. The present invention relates to a foreign matter inspection apparatus and a foreign matter inspection method for inspecting foreign matter.

In recent years, a color liquid crystal display (LCD) has been actively used as a flat display.
A color liquid crystal display uses three primary colors (R, G, B) as a constituent pixel portion, and performs color display by controlling transmission of each light of the three primary colors by electrical switching of the liquid crystal. There are an active matrix method and a simple matrix method, and a color filter (hereinafter also referred to as CF) is used in either method.
This color filter includes, for example, a colored layer composed of R, G, and B colored patterns on a transparent substrate, a black matrix located at a boundary portion of each pixel, a color filter layer composed of a protective layer and a transparent electrode layer. The liquid crystal display is used in the form of a color filter forming substrate.
As a method for producing such a color filter, a dyeing base material is applied on a glass substrate, and a pattern formed by exposure and development through a photomask is dyed. A coloring pigment is previously applied in a photosensitive resist. Disperse pigments by exposing and developing through a photomask, printing methods that print each color with printing ink, and coloring layers of each color by electrodeposition using transparent electrodes patterned on the substrate The electrodeposition method to be formed is known, but at present, the pigment dispersion method is the mainstream.
In the production of a color filter produced by the pigment dispersion method, the increase in the number of surfaces in the production stage has progressed due to the demand for reduction in production cost, the demand for an increase in the size of the display, and the like, and the processing substrate has become larger.

Exposure in the production of such a color filter produced by the pigment dispersion method is usually a proximity exposure method, and a pattern of an exposure mask (also referred to as an original plate) is applied to one surface of a glass substrate for forming a color filter. Transfer exposure is performed on the formed photosensitive color layer in which a color pigment is dispersed in advance in the photosensitive resist.
However, in the proximity exposure method in which the gap between the exposure mask and the substrate for forming the color filter is narrow, if there is a foreign matter in the colored layer on the substrate for forming the color filter for some reason, the exposure mask is damaged during exposure. There was a problem.
With the increase in the size of the glass substrate for forming the color filter, the exposure mask is also increased in size and becomes very expensive, and the cost of recreating the exposure mask due to scratches has become a problem.
There has been a demand for an apparatus for detecting a foreign matter in a colored layer on a substrate for forming a color filter before exposure with an exposure machine.
However, if you want to perform a foreign matter inspection to detect foreign matter in the colored layer on the color filter forming substrate just before exposure with the exposure machine, this is an inspection before exposure with the exposure machine, so that it does not affect the unexposed colored layer. In addition, there are many restrictions on the layout of the production line and the equipment configuration.

The applicant of the present application disclosed in Japanese Patent Application Laid-Open No. 10-48144 (Patent Document 1), an image obtained by photographing a color filter forming substrate on which a color filter layer is formed, which is being conveyed by a horizontal conveying means such as a conveyor, with a line sensor camera. Have proposed a foreign matter inspection apparatus for inspecting foreign matter by image processing.
However, what is described here is a foreign substance inspection for inspecting foreign substances on each color filter forming substrate after a step of exposure, development, etc., which has undergone a cutting process of cutting the one produced in multiple facets into each color filter forming substrate. It relates to the device.
JP, 10-48144, A When the foreign substance inspection which detects the foreign substance of the colored layer on the substrate for color filter formation just before exposing with an exposure machine is desired, due to the layout of the production line and the equipment configuration, as described above A mechanism such as conveyor conveyance may not be provided immediately before exposure.

As described above, in recent years, a color liquid crystal display (LCD) has been actively used, and as a method for forming a color filter of a color filter forming substrate provided with a color filter layer used for the color liquid crystal display, Currently, the production of color filters by the pigment dispersion method using proximity exposure is currently the mainstream, but due to demands for reducing manufacturing costs and the demand for larger display sizes, etc. As a result, the size of the processing substrate is increasing.
Under such circumstances, recently, in proximity exposure for patterning of an unexposed colored layer for forming a color filter, the exposure mask is damaged by foreign matter, and there are various limitations. There has been a demand for an apparatus for detecting foreign matter in an unexposed colored layer on a substrate for forming a color filter before exposure with an exposure machine that performs proximity exposure.
This invention respond | corresponds to this, and it is a foreign material inspection apparatus which detects the foreign material of the unexposed colored layer on the board | substrate for color filter formation before exposing with the exposure machine which performs proximity exposure, An unexposed colored layer It is an object of the present invention to provide a foreign substance inspection apparatus that can perform inspection so as not to affect the manufacturing process and that does not impose many restrictions on the layout of the production line and the device configuration.

The foreign matter inspection apparatus according to the present invention is configured so that the unexposed colored layer for forming the color filter disposed on the one surface side of the substrate is subjected to the exposure of the transfer mask pattern by proximity exposure. A foreign matter inspection apparatus for inspecting foreign matter, wherein a substrate on which the unexposed colored layer is disposed is a substrate to be inspected, a mounting table for mounting the substrate to be inspected in a horizontal state, and a side surface of the substrate to be inspected , One or more laser light irradiation units for irradiating a desired inspection region of the unexposed colored layer with a laser beam at an inclined angle, and a direction orthogonal to the unexposed colored layer forming surface of the substrate to be inspected. One or more photographing means for photographing the scattered light of the foreign matter of the laser light emitted from the laser light irradiating unit and acquiring the photographed image data by the scattered light over the entire inspection region; Each shot acquired by the shooting means The image data subjected to image processing, the entire inspection region, and an image processing unit for extracting a foreign matter in the colored layer of the unexposed, and is characterized in that it comprises.
In the foreign matter inspection apparatus described above, the wavelength of the laser light emitted from each laser light irradiation unit is deviated from the photosensitive wavelength of the unexposed colored layer.
Further, in any one of the above foreign matter inspection apparatuses, the wavelength of the laser light emitted from each laser light irradiation unit is a wavelength at which the spectral transmittance of the unexposed colored layer is low. It is.
Further, in the above foreign matter inspection apparatus, each laser light irradiation unit has a linear region as an irradiation region with respect to the unexposed colored layer of the substrate to be inspected. The linear irradiation area is scanned one-dimensionally along the surface of the unexposed colored layer by changing the position in the vertical direction with respect to the mounting table, and a predetermined surface area is irradiated. To do. Further, in the foreign matter inspection apparatus according to claim 4, each laser light irradiation unit is to uniformly spread the light from the light source in a planar manner to be emitted light, It irradiates the unexposed colored layer.
Alternatively, in the foreign matter inspection apparatus according to claim 4, each laser beam irradiating unit spreads light from the light source uniformly in a plane to be emitted light, and the laser beam spread in a plane Is reflected through a lens system or by a reflecting mirror made of a concave mirror to irradiate the unexposed colored layer as planar parallel light.
Alternatively, in the foreign matter inspection apparatus according to any one of claims 1 to 3, each laser light irradiation unit sets a predetermined region as an irradiation region with respect to an unexposed colored layer of the substrate to be inspected. Therefore, the irradiation area is scanned two-dimensionally along the unexposed colored layer surface to irradiate a predetermined surface area.
In any one of the above-described foreign matter inspection apparatuses, the mounting table is a pre-alignment stage of an exposure apparatus when performing the proximity exposure.
Moreover, in any one of the above foreign matter inspection apparatuses, the mounting table is a cooling plate (a plate with a temperature adjustment function).
Here, “irradiate the laser beam at an inclined angle” means that the laser beam is not in a direction orthogonal to the horizontal substrate to be inspected but in a direction inclined toward the unexposed colored layer, and each laser beam. This means that the laser beam is irradiated at an angle in a range where the specularly reflected light irradiated on the substrate to be inspected by the irradiation unit is not captured by each imaging means.
In addition, “light from the light source is uniformly spread in a plane to be emitted light” means that the light is spread uniformly from the light source to a plane in a plane to be emitted light. The shape is also called a fan shape.
The colored layer here is a photosensitive colored layer used for the production of a color filter by the pigment dispersion method described above, and is usually sensitive to UV light.

In the foreign matter inspection method of the present invention, an unexposed colored layer for forming a color filter disposed on one surface side of a substrate is subjected to transfer exposure of a transfer mask pattern by proximity exposure. A foreign matter inspection method for inspecting a foreign matter, wherein the substrate on which the unexposed colored layer is disposed is used as a substrate to be inspected, the substrate to be inspected is placed on a mounting table in a horizontal state, and the substrate is inspected from the side surface side. Irradiating a predetermined inspection area of the unexposed colored layer with a laser beam at an inclined angle, and arranging one or more photographings arranged on the upper side in a direction perpendicular to the unexposed colored layer forming surface of the inspected substrate Means for photographing scattered light in the foreign matter of the irradiated laser light, obtaining photographed image data by scattered light over the entire inspection area, subjecting the obtained photographed image data to image processing, and the entire inspection area Of the unexposed coloration It is characterized in that to extract foreign matter in. And it is said foreign material inspection method, Comprising: The wavelength of the irradiated laser beam has shifted | deviated from the photosensitive wavelength of the said unexposed colored layer, It is characterized by the above-mentioned.
In any one of the above foreign matter inspection methods, the wavelength of the irradiated laser beam is a wavelength at which the spectral transmittance of the unexposed colored layer is low.

(Function)
The foreign matter inspection apparatus according to the present invention is configured as described above to detect foreign matter on an unexposed colored layer on a color filter forming substrate before exposure by an exposure machine that performs proximity exposure. Therefore, it is possible to provide a foreign substance inspection apparatus that can inspect so as not to affect the unexposed colored layer and that does not impose many restrictions on the layout of the production line and the device configuration.
Specifically, a substrate on which an unexposed colored layer is disposed is a substrate to be inspected, a mounting table for placing the inspected substrate in a horizontal state, and a desired unexposed colored layer on the side surface of the inspected substrate The inspection region is arranged at the upper side in a direction orthogonal to the unexposed colored layer forming surface of the substrate to be inspected, and one or more laser light irradiation portions that irradiate laser light at an inclined angle, and the laser light irradiation The scattered light of the laser beam irradiated from the part is photographed, and the photographed image data by the scattered light is obtained over the entire inspection region, and each of the photographed means obtained by each of the photographing means This is achieved by providing an image processing unit that performs image processing on the photographed image data and extracts foreign matter in the unexposed colored layer in the entire inspection region.
In other words, the laser beam from the laser beam irradiator generates scattered light that hits the foreign matter. However, the laser beam can be irradiated over the entire desired area of the unexposed colored layer of the substrate to be inspected, and the desired unexposed colored layer can be irradiated. It is possible to photograph scattered light from foreign matter over the entire area, and further includes an image processing unit, and from the photographed image data photographed with scattered light, the presence or absence of foreign matter over the entire desired area of the unexposed colored layer is detected. It is possible to detect.
The laser beam is not particularly limited as long as it has an intensity capable of detecting scattered light from a foreign substance by an imaging means (camera) and avoids the photosensitive wavelength of the unexposed colored layer.
Here, by using laser light, scattering is likely to occur, and since laser light has high straightness, the amount of light can be increased even at a relatively low output.
In addition, since the wavelength of the laser beam is high, the wavelength of the laser beam (peak wavelength) is unexposed and colored by laser beam irradiation by adopting the form of the invention of claim 2 in which the wavelength of the laser beam is deviated from the photosensitive wavelength to some extent. The layer can be made light-sensitive.
For example, a red laser having a wavelength of 655 nm can be used while avoiding the photosensitive wavelength.
Further, the wavelength of the laser light emitted from each laser light irradiation part is a wavelength at which the spectral transmittance of the unexposed colored layer is low. Thus, the influence of reflected light can be reduced.
This corresponds to the case where an unexposed colored layer of G color (green) or B color (blue) is inspected with a red laser having a wavelength of 655 nm.
Note that a light source obtained by beam-shaping by spreading a laser beam uniformly in a plane in a fan shape is commercially available. As the image processing unit, for example, there is an image processing unit that binarizes captured image data at a predetermined threshold, calculates a pixel connection degree, and has a process of recognizing that there is a foreign object defect when a predetermined number of pixels are connected. .
In reality, the brightness and size when scattered light is captured by the imaging means (camera) are affected by the height at which the foreign object protrudes from the unexposed colored layer, the size and shape of the foreign object, and therefore the scattered light. Assuming that the strength and size are large, the protruding height is large.
In addition, qualitatively, the scattered light intensity is stronger as the shape of the foreign material is more jagged.
In general, the larger the size of the foreign matter is, the more protruding from the colored layer, and the occurrence of scratches on the transfer mask is. Therefore, the extraction of foreign matter by such image processing is effective.

More specifically, each laser beam irradiation unit has a linear region as an irradiation region with respect to the unexposed colored layer of the substrate to be inspected, and the vertical direction of each laser beam irradiation unit and the mounting table described above. The form of the invention of claim 4 is one in which the linear irradiation region is scanned one-dimensionally along the surface of the unexposed colored layer by irradiating a predetermined surface region. However, it is easy to manage the relative position in the top-and-bottom direction by integrating the laser beam irradiation unit, and in this case, it is possible to easily perform one-dimensional scanning with high accuracy and stability.
In this case, each laser beam irradiating unit spreads light from the light source in a planar manner to emit light, and irradiates the unexposed colored layer in a planarly spread state. The form of the invention of 5 or each laser beam irradiating section is to spread the light from the light source in a plane to be emitted light. The laser beam spread in a plane is passed through a lens system or a concave mirror. An embodiment of the invention of claim 6 is used in which the unexposed colored layer is irradiated as planar parallel light reflected by a reflection mirror made of the above. It is possible to reduce the overlap of the laser beams irradiated from the portion, and to irradiate almost all of the inspection region with the light that is uniform in intensity, thereby enabling the extraction of foreign matters with high accuracy.

Further, in the invention of any one of claims 1 to 3, each laser beam irradiation unit has a predetermined area as an irradiation area with respect to an unexposed colored layer of the substrate to be inspected, and the irradiation area is not set. An embodiment of the invention of claim 7 is also one in which a predetermined surface area is irradiated by scanning two-dimensionally along the colored layer surface of exposure.
In this case, it is possible to reduce the number of laser beam irradiation units to one, but two-dimensional scanning is required.
For example, the unit irradiation area is scanned using a linear galvanometer mirror to form a line, and the position of the laser beam irradiation unit and the mounting table in the vertical direction described above is relatively changed. Can be scanned two-dimensionally.

Further, the mounting table is a pre-alignment stage of the exposure apparatus when performing the proximity exposure. By adopting the form of the invention of claim 8, the exposure operation in the exposure apparatus when performing the proximity exposure is efficiently performed. It is possible to do.
In addition, when the pattern of the transfer mask is transferred and exposed to the unexposed colored layer for forming the color filter by proximity exposure, the color for exposure is usually applied to the stage at the time of exposure from the viewpoint of productivity. Before the filter forming substrate is placed, pre-alignment is performed in advance, and a stage for performing this pre-alignment is a pre-alignment stage.
In addition, since the mounting table is a cooling plate (a plate with a temperature adjustment function), it is possible to detect a foreign object with good accuracy, and when the mounting table is a pre-alignment stage of an exposure apparatus, It enables exposure with high accuracy.

  In the foreign matter inspection method of the present invention, the foreign matter inspection method for detecting foreign matter in the unexposed colored layer on the substrate for forming a color filter before exposure by an exposure machine that performs proximity exposure by using such a configuration. Thus, it is possible to provide a foreign matter inspection method that can perform inspection so as not to affect the unexposed colored layer and that does not impose much restrictions on the layout of the production line and the device configuration.

As described above, the present invention is a foreign matter inspection apparatus for detecting foreign matter in an unexposed colored layer on a substrate for forming a color filter before exposure with an exposure machine that performs proximity exposure. It has become possible to provide a foreign substance inspection apparatus that can perform inspections without affecting them and that does not impose much restrictions on the layout of the production line and the equipment configuration.
At the same time, a foreign matter inspection method for detecting foreign matter in an unexposed colored layer on a color filter forming substrate before exposure by an exposure machine that performs proximity exposure is performed so as not to affect the unexposed colored layer. It is possible to provide a foreign matter inspection method that can be applied and that does not impose many restrictions on the layout and equipment configuration of the production line.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 (a) is a schematic perspective view of an example of an embodiment of the foreign matter inspection apparatus of the present invention, FIG. 1 (b) is a cross-sectional view taken along A1-A2 in FIG. 1 (a), and FIG. 3 is a block diagram of the foreign matter inspection apparatus shown in FIG. 1, FIG. 3 is a schematic diagram for explaining imaging by scattered light, FIG. 4 (a) is a plan view for explaining laser light irradiation and irradiation regions, and FIG. 4 (b) is a view seen from the B1 side of FIG. 4 (a), FIG. 5 is a view showing laser irradiation by a plurality of laser irradiation units, and FIG. 6 (a) is a laser beam parallel using a mirror. FIG. 6B is a diagram of a case where laser light is converted into parallel light using a lens, and FIG. 7 is a diagram of a mode of irradiating laser light reflected using a reflection mirror. FIG. 8 is a diagram of a form in which laser light is irradiated from both sides using a reflection mirror.
1 to 8, 10 is a pre-alignment stage (also referred to as a mounting table), 20 is a substrate to be inspected, 30 is a photographing means (CCD camera), 40 is a laser light irradiation unit, 45 is laser light, and 45A is scattered light. , 47, 48 are laser beam irradiation areas, 50 is a laser support base (movable up and down), 60 is a personal computer for control and processing (also referred to as a control unit and image processing unit), 80 is a foreign object, 90 is a concave reflecting mirror, 91 , 92 are plane reflecting mirrors, and 95 is a lens system.

First, an example of an embodiment of the foreign matter inspection apparatus of the present invention will be described with reference to FIG.
The foreign matter inspection apparatus according to the present embodiment transfers the pattern of the transfer mask by proximity exposure to the unexposed colored layer for forming the color filter disposed on the one surface side of the substrate. In a foreign matter inspection apparatus for inspecting foreign matter, a pre-alignment stage 10 for an exposure machine (not shown) that performs proximity exposure and a substrate (hereinafter referred to as a substrate to be inspected) on which an unexposed colored layer for performing foreign matter inspection is arranged It is said to be a mounting table for mounting.
As described above, an exposure substrate on which an unexposed colored layer is disposed for exposure is usually placed on an exposure stage of an exposure machine (not shown) that performs proximity exposure. At this time, pre-alignment is performed in advance on a dedicated pre-alignment stage, and after the pre-alignment is performed, an exposure substrate is placed on an exposure stage of an exposure machine (not shown) to perform an exposure process.
Then, the substrate on which the unexposed colored layer is disposed is used as the substrate to be inspected 20, and in addition to the pre-alignment stage 10 on which the substrate to be inspected 20 is placed in a horizontal state, A desired inspection region of the colored layer is arranged on the upper side in a direction perpendicular to the unexposed colored layer forming surface of the plurality of laser light irradiation units 40 irradiating the laser beam 45 at an inclined angle and the substrate 20 to be inspected. A plurality of imaging means 30 comprising a CCD area sensor camera for imaging scattered light of the laser beam emitted from the laser light irradiation unit and acquiring image data of the scattered light over the entire inspection area; The image processing unit 30 performs image processing on each captured image data captured by each imaging unit 30, and serves as an image processing unit that extracts foreign matter in the unexposed colored layer of the entire inspection region and a control unit that controls each unit. And the personal computer 60 for control and processing, and includes.
In this example, the wavelength of the laser beam emitted from each laser beam irradiation unit is shifted from the photosensitive wavelength of the colored layer of the substrate 20 to be inspected.
As shown in the block diagram of FIG. 2, the foreign matter inspection apparatus of this example is controlled in association with each unit under the control of the control / processing personal computer 60.

The pre-alignment stage 10 is pre-aligned in advance when a substrate on which an unexposed colored layer is arranged for exposure is placed on an exposure stage of an exposure machine (not shown) that performs proximity exposure. This stage has a function for performing slight X and Y position correction and rotation correction.
As the photographing means 30, a CCD area sensor camera is used because the pre-alignment stage 10 of an exposure machine (not shown) that performs proximity exposure is used as a mounting table.
The plurality of imaging means 30 can image the entire inspection area and obtain image data of the entire inspection area.
As shown in FIG. 3, the imaging unit 30 receives the scattered light 45 </ b> A of the laser light 45 applied to the foreign material 80 as a foreign material part and images it, and also captures the entire inspection region using the scattered light. Get image data.
The angle θ is an angle formed between the laser beam 45 and the substrate to be inspected, and the laser beam 45 is not in a direction perpendicular to the substrate to be inspected in the horizontal state, but in a direction inclined toward the unexposed colored layer side. In addition, the specularly reflected light irradiated to the substrate 20 to be inspected by each laser light irradiation unit is irradiated at an angle in a range where the image capturing unit 30 does not capture the image.
The laser support base 50 is configured to fix and hold a plurality of laser beam irradiation units 40 and to move up and down (moving in the vertical direction) integrally.
The control personal computer 60 performs image processing on the captured image data photographed by each photographing means 30, and serves as an image processing unit that extracts foreign matters in the unexposed colored layer of the substrate 20 to be inspected and a control unit that controls each unit. ing.

Here, the laser beam irradiation unit 40 irradiates the laser beam in a fan-shaped flatly spread state, and in combination with the irradiation from the plurality of laser beam irradiation units 40, the substrate 20 to be inspected is not exposed. A predetermined inspection region of the colored layer is irradiated.
The laser beam irradiation unit 40 is fixed and held on a laser support table 50 that can move up and down (moves up and down), and can be moved up and down by the laser support table 50.
When the position of the laser light irradiation unit 40 is fixed, the laser light from each laser light irradiation unit 40 irradiates the linear region of the colored layer from an oblique direction. For example, FIG. As shown in FIG. 4B, at the Ph1 position, the P1-P2 linear region of the inspected substrate 20 is irradiated, and at the Ph2 position, the P3-P4 linear region of the inspected substrate 20 is irradiated. .
Then, the entire region P1, P2, P4, P3 is irradiated by moving the laser beam irradiation unit 40 in the vertical direction from the Ph1 position to the Ph2 position.
If each imaging means 30 is set in the imaging state during the vertical movement of each laser beam irradiation unit 40 from the Ph1 position to the Ph2 position, the foreign matter inspection can be performed on the entire areas P1, P2, P4, and P3.
A single laser light irradiation unit 40 cannot inspect the entire desired inspection region, and a plurality of laser light irradiation units 40 are mounted on a laser support base 50 that can be moved up and down, and these are moved up and down together to form a desired one. The entire inspection area can be inspected.
As shown in FIG. 5, the irradiation areas from the laser light irradiation units 40 overlap on the colored layer of the substrate 20 to be inspected.

The laser beam 45 is not particularly limited as long as it has an intensity capable of detecting scattered light from a foreign substance by the photographing means (camera) 30 and avoids the photosensitive wavelength of the unexposed colored layer.
By removing the wavelength (peak wavelength) of the laser beam 45 from the photosensitive wavelength to some extent, it is possible to eliminate the exposure of the unexposed colored layer by the laser beam 45 irradiation.
Moreover, from the surface which transmits the unexposed colored layer and reduces the influence of reflected light, the wavelength of the laser beam 45 irradiated from each laser beam irradiation unit 40 is the spectral transmittance of the unexposed colored layer. Is preferably a low wavelength.
For example, when a colored layer of each of R color (red), G color (green), and B color (blue) is to be inspected, the laser light has a wavelength of 655 nm excluding the photosensitive wavelength of each color. A red laser can be used.
In particular, when a red laser having a wavelength of 655 nm is used with a G color (green) colored layer or a B color (blue) colored layer as an inspection target, the wavelength of the laser light 45 is the spectral transmittance of the unexposed colored layer. Is preferable because of its low wavelength.

Next, an example of the processing flow of the foreign matter inspection apparatus of this example will be briefly described below.
Note that this replaces the description of the embodiment of the foreign matter inspection method of the present invention.
Here, it is assumed that a predetermined width is inspected between the extension line including the linear regions P1-P2 and the extension line including the linear regions P3-P4 shown in FIG.
First, the substrate 20 to be inspected is placed on the pre-alignment stage 10 at a predetermined position.
The laser support base 50 is moved up and down, the laser beam irradiation units 40 are moved together to the position Ph1, and the linear region P1-P2 is irradiated. Are moved to the Ph2 position.
When moving from the Ph1 position to the Ph2 position, each photographing means 30 is set in a state where it can continue photographing, and photographing is performed throughout this movement.
Each photographing unit 30 photographs the scattered light of the laser light emitted from the laser light illumination unit 40 if there is a foreign object in each photographing region.
The photographed image data photographed by each photographing means 30 is sent to the control personal computer 60 and subjected to image processing.
As the image processing, for example, the captured image data is binarized at a predetermined threshold value, the degree of pixel connection is calculated, and if a predetermined number of pixels are connected, processing for recognizing that there is a foreign object defect is performed.
Note that the brightness and size when scattered light is captured by the imaging means (camera) are affected by the height at which the foreign object protrudes from the unexposed colored layer, the size and shape of the foreign material. A large size may be evaluated as having a large protruding height.
In this way, it is possible to extract foreign matter from the unexposed colored layer of the substrate to be exposed 20 that causes scratches on the transfer mask during proximity exposure.

Since the color filter forming substrate is transmissive except for the substrate on which the black matrix is disposed, the light transmitted through the color filter forming substrate is inspected on the mounting table (also referred to as a stage) at the time of inspection. When reflected by a reflector and brightly shining, it may remain on the binarized image and cause erroneous information.
Since the position of such a reflecting object is fixed, it is detected as a defect even if a binarized image having a predetermined number of connections or more remains in the corresponding place by registering the surrounding area as a non-inspection area in advance. Do not be.
When the laser light having a wavelength band having a low spectral transmittance of the colored layer disposed on the color filter forming substrate is selected as the irradiation light, the influence of the above-described reflector can be reduced.
In other words, the wavelength of the laser light emitted from each laser light irradiation unit is set to a wavelength at which the spectral transmittance of the unexposed colored layer is low, so that the influence of the light that is transmitted through the unexposed colored layer and reflected. Can be reduced.

This example is one example, and the present invention is not limited to this example.
In the case of this example, each laser beam irradiating unit spreads the light from the light source in a fan shape in a planar manner to be emitted light, and irradiates the substrate as it is as shown in FIG. 6B. In addition, the laser beam spread in a fan shape on a plane is reflected through a lens system 95, or the laser beam spread in a fan shape on a plane as shown in FIG. 6A is reflected by a concave reflecting mirror 90 made of a concave mirror. In addition, the substrate to be inspected may be irradiated as planar parallel light.
In the case of this form, it is possible to reduce the overlap of the laser beams irradiated from the respective laser beam irradiation units, and to irradiate almost all of the inspection area with the uniform light in intensity. Extraction is possible.
In addition, as shown in FIG. 7, there is also a mode in which the laser beam 45 from the laser beam irradiation unit 40 is reflected by the plane reflection mirror 91 and irradiated.
Moreover, as shown in FIG. 8, the form which irradiates from both sides using the plane reflection mirror 92 can also be mentioned.

FIG. 1A is a schematic perspective view of an example of an embodiment of a foreign matter inspection apparatus according to the present invention, and FIG. 1B is a cross-sectional view taken along line A1-A2 of FIG. It is a block diagram of the foreign material inspection apparatus shown in FIG. It is the schematic for demonstrating imaging | photography by scattered light. FIG. 4A is a plan view for explaining the laser light irradiation and the irradiation region, and FIG. 4B is a view seen from the B1 side of FIG. 4A. It is the figure which showed the laser irradiation by a several laser irradiation part. FIG. 6A is a diagram in the case where the laser beam is converted into parallel light using a mirror, and FIG. 6B is a diagram in the case where the laser beam is converted into parallel light using a lens. It is a figure of the form which irradiates the laser beam reflected using the reflective mirror. It is a figure of the form which irradiates a laser beam from both sides using a reflective mirror.

Explanation of symbols

10 Pre-alignment stage (also called mounting table)
20 Inspected substrate 30 Imaging means (CCD camera)
40 Laser light irradiation section 45 Laser light 45A Scattered light 47, 48 Laser light irradiation area 50 (movable up and down) Laser support base 60 Control and processing personal computer (also referred to as control section and image processing section)
80 Foreign object 90 Concave reflection mirrors 91 and 92 Planar reflection mirror 95 Lens system

Claims (12)

  A foreign matter inspection apparatus that inspects a foreign matter before transferring and exposing a pattern of a transfer mask by proximity exposure to an unexposed colored layer disposed on one side of a substrate to form a color filter. A substrate on which the unexposed colored layer is disposed as a substrate to be inspected, a mounting table for placing the substrate to be inspected in a horizontal state, and a desired unexposed colored layer on the side surface of the inspected substrate. The inspection region is arranged at the upper side in a direction orthogonal to the unexposed colored layer forming surface of the substrate to be inspected, and one or more laser light irradiation portions that irradiate laser light at an inclined angle, and the laser light irradiation The scattered light of the laser beam irradiated from the part is photographed, and the photographed image data by the scattered light is obtained over the entire inspection region, and each of the photographed means obtained by each of the photographing means Process the captured image data The inspection of the entire region, said image processing unit for extracting a foreign matter in the colored layer in the unexposed, particle inspection apparatus characterized by comprising.   The foreign matter inspection apparatus according to claim 1, wherein the wavelength of the laser light emitted from each laser light irradiation unit is shifted from the photosensitive wavelength of the unexposed colored layer. apparatus.   3. The foreign matter inspection apparatus according to claim 1, wherein the wavelength of the laser light emitted from each laser light irradiation unit is a wavelength at which a spectral transmittance of the unexposed colored layer is low. Foreign matter inspection apparatus characterized by the above.   4. The foreign matter inspection apparatus according to claim 1, wherein each laser light irradiation unit uses a linear region as an irradiation region with respect to an unexposed colored layer of the substrate to be inspected. By linearly changing the position of each laser beam irradiation unit and the mounting table in the vertical direction, the linear irradiation region is scanned one-dimensionally along the unexposed colored layer surface, and a predetermined surface region is scanned. A foreign matter inspection apparatus characterized by being irradiated.   5. The foreign matter inspection apparatus according to claim 4, wherein each laser beam irradiating unit uniformly spreads light from the light source in a planar manner to be emitted light. A foreign matter inspection apparatus for irradiating a colored layer for exposure.   5. The foreign matter inspection apparatus according to claim 4, wherein each laser beam irradiating unit spreads light from the light source uniformly in a plane to be emitted light, and the laser beam spread in a plane is converted into a lens. A foreign matter inspection apparatus that irradiates the unexposed colored layer as planar parallel light through a system or reflected by a reflecting mirror made of a concave mirror.   4. The foreign matter inspection apparatus according to claim 1, wherein each laser beam irradiation unit sets a predetermined area as an irradiation area with respect to an unexposed colored layer of the substrate to be inspected. A foreign matter inspection apparatus characterized by irradiating a predetermined surface region by two-dimensionally scanning the irradiation region along an unexposed colored layer surface.   The foreign matter inspection apparatus according to any one of claims 1 to 7, wherein the mounting table is a pre-alignment stage of an exposure device when performing the proximity exposure.   The foreign matter inspection apparatus according to any one of claims 1 to 8, wherein the mounting table is a cooling plate (a plate with a temperature adjustment function).   A foreign matter inspection method for inspecting a foreign matter before transferring a transfer mask pattern by proximity exposure to an unexposed colored layer for forming a color filter disposed on one side of a substrate. The substrate on which the unexposed colored layer is disposed is used as a substrate to be inspected, the substrate to be inspected is placed on a mounting table in a horizontal state, and is unexposed at an inclined angle from the side surface side of the substrate to be inspected. The irradiated laser is irradiated with a laser beam to a predetermined inspection region of the colored layer, and is irradiated by one or more photographing means arranged on the upper side in a direction orthogonal to the unexposed colored layer forming surface of the substrate to be inspected. The scattered light in the foreign matter is imaged, the captured image data by the scattered light is acquired over the entire inspection area, the acquired captured image data is subjected to image processing, and the unexposed colored layer in the entire inspection area Foreign matter in Particle inspection method comprising and.   The foreign matter inspection method according to claim 10, wherein the wavelength of the irradiated laser beam is shifted from the photosensitive wavelength of the unexposed colored layer. 12. The foreign matter inspection method according to claim 10, wherein the wavelength of the irradiated laser beam is a wavelength at which a spectral transmittance of the unexposed colored layer is low. Inspection method.

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