JP2005181194A - Stage for optical device, defect inspecting device, and the optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stage for optical devices and an optical stage using it, capable of accurately carrying out observations, measurements or the like. <P>SOLUTION: The stage 13 for the optical devices is equipped with a mount surface 13a, which is subjected to optical polishing and on which a substrate 14 is mounted, and a hole 21 formed in the mount surface 13a. The hole 21 has a chamfered section 21b, formed by chamfering on the side of the mount surface 13a, and the chamfer section 21b is subjected to the optical polishing, and a plane, intersecting with the mount surface 13a of the hole 21, is made to inclined downward from the mount surface 13a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical apparatus stage, a defect inspection apparatus using the same, and an optical apparatus.

  In order to improve the yield of liquid crystal display devices, there is a defect inspection device that inspects a color filter substrate. In a defect inspection apparatus for a color filter substrate, the substrate is irradiated with light, and the reflected light or transmitted light is detected by a detector to determine the presence or absence of a defect.

  In a transmission type defect inspection apparatus using transmitted light, a color filter substrate as a target object is placed on a stage in order to hold it in a stable state. Then, light from the light source is irradiated from the front surface side or the back surface side of the substrate with the substrate placed on the stage, and the light is transmitted through the substrate and the stage and detected by a CCD or photodiode detector. Therefore, a transparent stage that transmits light from a light source is used as a stage used in a transmission type defect inspection apparatus (Patent Document 1).

  A stage having an opening in the measurement region of the substrate can also be used. However, when a large opening is provided in the stage, the substrate is bent. In particular, the larger the substrate, the larger the amount of deflection, and there is a problem that the inspection cannot be performed accurately.

  A transparent stage used in the defect inspection apparatus will be described with reference to FIG. FIG. 5 is a side sectional view showing the structure of the stage. FIG. 5 shows an enlarged configuration of the stage on which the substrate is placed.

  A substrate 14 on which a color filter is formed is placed on the transparent stage 13. A light source (not shown) is provided on the back side of the substrate. Light from this light source enters the lens 12. The lens 12 collects incident light and makes the light incident on a substrate 14 made of a transparent material such as glass placed on a stage. Light incident on the substrate through the transparent stage 13 passes through the substrate 14. The light transmitted through the substrate enters the lens 15 disposed above the stage. Then, the light from the lens 15 is taken into a photodetector (not shown) such as a CCD or a photodiode. The photodetector outputs a signal based on the intensity of the captured light. The processing device performs a predetermined process based on this signal to inspect the defect.

  The stage 13 is usually provided with a plurality of holes 21 for transporting the substrate 14. That is, a support pin (not shown) lifts the substrate 14 from the hole 21 when the substrate is transported, and a gap is provided between the substrate 14 and the stage 13. The substrate transfer robot enters the gap, and the support pins are lowered to transfer the substrate 14 from the stage to the substrate transfer robot. Then, the substrate 14 is transferred by moving the substrate transfer robot while the substrate 14 is transferred from the stage 13 to the transfer robot.

However, when the substrate 14 is inspected at a position corresponding to the hole 21 on the stage used in the conventional defect inspection apparatus, there are the following problems. For example, a glass processing mark is provided at the edge 22 where the placement surface 13a on which the substrate 14 of the stage 13 is placed and the side portion 21a of the hole 21 intersect. The transmitted image is shaded as it is in the vicinity of the image plane. End up. In particular, when the NA (numerical aperture) of the objective lens is small, glass processing traces form an image, which increases the influence on observation and measurement. Accordingly, there is a problem that the processing trace of the glass affects the measurement and observation at the edge portion of the hole 21.
JP 2001-148625 A (paragraph number 0011)

As described above, the conventional defect inspection apparatus has a problem that the holes provided in the stage affect observation, measurement, and the like.
The present invention has been made in view of the above problems, and an object thereof is to provide a stage for an optical device capable of accurately observing, measuring, etc., a defect inspection apparatus using the same, and an optical device. .

  The stage for an optical device according to the first aspect of the present invention has a mounting surface (for example, the mounting surface 13a in the present embodiment) for mounting a target object (for example, the substrate 14 in the present embodiment). A transparent optical device stage comprising an optically polished mounting surface and a hole (for example, hole 21 in the present embodiment) provided in the mounting surface, The surface intersecting with the mounting surface is optically polished. Thereby, it is possible to observe and measure the target object without being affected by the edge.

  The stage for an optical device according to the second aspect of the present invention is the above-described stage for an optical device, wherein a surface that intersects the placement surface of the hole is inclined below the placement surface. Thereby, a target object can be stably mounted on a mounting surface.

  The optical device stage according to a third aspect of the present invention is the above optical device stage, further comprising a chamfered portion chamfered on the mounting surface side of the hole, and the chamfered portion and the mounting surface described above. Are crossed. Thereby, it is possible to easily form a hole in which the influence of the edge is reduced.

  An optical device according to a fourth aspect of the present invention includes the above-described optical device stage. Thereby, it is possible to observe and measure the target object without being affected by the edge.

  A defect inspection apparatus according to a fifth aspect of the present invention includes: a light source that irradiates light to a color filter substrate; a detector that detects light from the light source that has passed through the color filter substrate; and the color filter substrate. A defect inspection apparatus provided with a transparent stage in which a hole is formed on a mounting surface to be mounted, wherein a surface intersecting the mounting surface and the mounting surface of the hole is optically polished It is. Thereby, it is possible to observe and measure the target object without being affected by the edge.

  A defect inspection apparatus according to a sixth aspect of the present invention is the above-described defect inspection apparatus, wherein a surface of the hole intersecting with the placement surface described above is inclined below the placement surface. Thereby, a target object can be stably mounted on a mounting surface.

  The defect inspection apparatus according to a seventh aspect of the present invention is the above-described defect inspection apparatus, further comprising a chamfered portion that chamfers the mounting surface side of the hole, and the chamfered portion and the mounting surface intersect each other. It is what you are doing. Thereby, it is possible to easily form a hole in which the influence of the edge is reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the stage for optical apparatuses which can perform observation, a measurement, etc. correctly, a defect inspection apparatus using the same, and an optical apparatus can be provided.

  Hereinafter, embodiments to which the present invention can be applied will be described. The following description is to describe the embodiment of the present invention, and the present invention is not limited to the following embodiment. For clarity of explanation, the following description is omitted and simplified as appropriate. Further, those skilled in the art will be able to easily change, add, and convert each element of the following embodiments within the scope of the present invention. In addition, what attached | subjected the same code | symbol in each figure has shown the same element, and abbreviate | omits description suitably.

  A defect inspection apparatus according to the present invention will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of a transmission type defect inspection apparatus according to the present embodiment. 1 is an optical device, 11 is a light source, 12 is a lens, 13 is a stage 13 is a substrate, 15 is a lens, 16 is a detector, and 17 is a processing device.

  The defect inspection apparatus according to the present embodiment is a defect inspection apparatus for performing a defect inspection of a color filter substrate used in a liquid crystal display device. The substrate 14 used for the color filter is usually a transparent glass substrate having a thickness of 0.5 mm to 1.1 mm, and a black matrix and a colored layer are provided on the surface side of the substrate 14. Inspection is performed by placing the substrate 14 on a transparent stage so that the stage 13 is in contact with the surface (back surface) opposite to the surface on which the black matrix and the colored layer are provided. The stage 13 is usually provided to place the substrate 14 horizontally.

  In the present embodiment, light is irradiated from the back side of the color filter substrate 14 through the stage 13. And the light which permeate | transmitted the board | substrate 14 is detected by the detector 16, and the presence or absence of a defect is discriminate | determined based on the light quantity of the light which the detector 16 detected. For example, when a white defect that transmits light is formed on the substrate 14 on which the color filter is formed, the light amount detected by the detector 16 is higher than a predetermined light amount. On the other hand, when the black defect which shields light is formed in the board | substrate 14, the light quantity which the detector 16 detects becomes lower than predetermined light quantity. The presence / absence of a defect can be determined based on fluctuations in the amount of light detected by the detector 16.

  Light from the light source 11 enters the lens 12. The light source 11 only needs to emit light, such as a laser light source or a lamp light source. The light incident on the lens 12 is condensed so as to illuminate the detection spot on the surface of the substrate 14. The light collected by the lens 12 passes through the stage 13 and enters the substrate 14. The stage 13 is formed of a transparent material such as glass so as to transmit light from the light source 11. Of course, when the light source 11 is light of only a specific wavelength such as a laser light source, light of that wavelength may be transmitted. Further, it may be formed of a material that transmits only a part of the incident light. In this way, the detection area of the substrate 14 is illuminated.

  The light incident on the substrate 14 passes through the substrate 14 and enters the lens 15. The lens 15 which is an objective lens collects light so as to enter the detector 16. The detector 16 is a photodetector such as a CCD camera or a photodiode, and outputs information related to the amount of incident light to the processing device 17. The processing device 17 is an information processing device such as a personal computer (PC), and performs a predetermined process based on information regarding the input light quantity. The processing device 17 determines the presence or absence of a defect based on the processing result. Further, the optical system including the detector 16 and the light source 11 is driven horizontally in conjunction with the inspection to inspect the entire surface of the substrate. Alternatively, the stage 13 may be driven to inspect the entire surface of the substrate.

  The above stage will be described in detail with reference to FIG. FIG. 2 is a diagram showing a configuration of the stage 13 in a state where the substrate 14 is placed. FIG. 2A is a side sectional view of the stage 13, and FIG. 2B is a top view of the stage 13.

  The stage 13 is usually provided with a hole 21 for transporting the substrate 14. As shown in FIG. 2B, the stage 13 is provided with four holes 21. The four holes 21 are provided at positions corresponding to the four corners of the substrate 14, respectively. A support pin 18 is provided below the stage 13 as shown in FIG. The support pin 18 is disposed at a position corresponding to the hole 21. The support pin 18 is provided so as to be movable in the vertical direction, and can be inserted into the hole 21.

  When transporting the substrate 14 placed on the stage, the support pins 18 are moved upward and inserted into the holes 21. The support pins 18 come into contact with the lower surface of the substrate 14 through the holes 21 to lift the substrate 14 and provide a gap between the substrate 14 and the stage 13. The substrate transfer robot enters the gap and lowers the support pins 18, whereby the substrate 14 is transferred from the stage to the substrate transfer robot. Then, the substrate 14 is transferred by moving the substrate transfer robot while the substrate 14 is transferred from the stage 13 to the transfer robot. When the substrate 14 is transferred onto the stage, the substrate 14 is transferred onto the stage according to the reverse procedure. Note that the support pin 18 is moved below the optical system so as not to affect the inspection during the inspection.

  A configuration when the substrate 14 is inspected at the position of the hole 21 provided in the stage 13 will be described with reference to FIG. FIG. 3 is a side sectional view of the stage 13 at the position of the hole 21. Reference numeral 13 a denotes a mounting surface of the substrate 14 on the stage 13. Reference numeral 21 a denotes a side portion of the hole 21, and 21 b denotes a chamfered portion of the hole 21. Reference numeral 22 denotes an edge where the mounting surface 13a and the hole 21 intersect. The hole 21 includes a side portion 21a perpendicular to the placement surface 13a and a chamfered portion 21b provided between the side portion 21a and the placement surface 13a.

  When the substrate 14 is inspected at the position of the hole, the optical system is moved to align the lens 12 and the lens 15 with the position of the hole 21 as shown in FIG. Of course, the detector 16 and the light source 11 shown in FIG. 1 also move in the same manner. Alternatively, the stage 13 may be moved to align the position of the hole 21 with the positions of the lens 12 and the lens 15. The hole 21 has a diameter of about 10 mm to 50 mm, for example, and is provided so as to penetrate the stage 13 having a thickness of 10 mm.

  A placement surface 13a of the stage 13 on which the substrate 14 is placed is provided horizontally so as to place the substrate 14 horizontally. The stage 13 is processed in a direction perpendicular to the placement surface 13a, and a hole 21 is formed. Therefore, the side portion 21a of the hole 21 is formed perpendicular to the placement surface 13a. Further, a chamfered portion 21b is formed between the side portion 21a and the placement surface 13a. That is, the edge 22 where the upper end 23 of the side portion 21a and the mounting surface 13a intersect is processed to be chamfered. The upper part of the hole 21 is chamfered, and the side surface of the hole is composed of a side part 21a and a chamfered part 21b. In the present embodiment, since the chamfered portion 21b is provided between the side surface 21a perpendicular to the placement surface 13a and the placement surface, it can be easily processed.

  The chamfered portion 21b is optically polished and becomes an optically polished surface. Further, the mounting surface 13a is also optically polished and is an optically polished surface. Since the edge 22 is a ridge line between the mounting surface 13a, which is an optical polishing surface, and a chamfered portion 21b, which is an optical polishing surface, it is possible to prevent a decrease in transmittance at the edge 22 portion. Therefore, even when the portion of the edge 22 is inspected, the transmitted light can be accurately inspected without being affected by the edge 22.

  The chamfered portion 21b, that is, the surface that intersects the placement surface 13a of the hole 21 is inclined downward from the placement surface 13a. Therefore, the substrate 14 can be placed horizontally on the placement surface 13a. Thereby, the board | substrate 14 can be stably mounted in the mounting surface 13a of the stage 13, and an exact test | inspection can be performed.

  Since the distance between the upper end 23 of the side portion 21a and the surface opposite to the mounting surface 13a of the stage 13 is, for example, about 2 mm, the length of the side portion 21a is about 8 mm. The chamfered portion 21b is provided so as to be inclined 45 ° downward from the placement surface 13a. Therefore, for example, if the diameter of the side portion 21a of the hole 21 is 10 mm, the diameter of the hole 21 in the mounting surface 13a is 14 mm.

  In the case of optical polishing, a polishing liquid containing abrasive grains dispersed on the polishing surface is dropped. Then, polishing is performed by pressing the cloth against the polishing surface. Alternatively, polishing paper or the like to which abrasive grains are attached may be used without using cloth and polishing liquid. In the present embodiment, the mounting surface 13a and the inclined chamfer 21b are optically polished. Therefore, optical polishing can be easily performed as compared with the side portion 21a provided perpendicular to the mounting surface 13a. For example, the side portion 21a of the hole 21 perpendicular to the mounting surface 13a is used as a processing surface, and only the chamfered portion 21b that is inclined with respect to the mounting surface 13a is used as an optical polishing surface. With such a configuration, the inside of the hole 21 can be easily optically polished, so that a stage in which the influence of the edge portion is reduced can be manufactured at low cost.

  On the other hand, the upper end 23 of the side portion where the side portion 21a and the chamfered portion 21b intersect becomes a ridge line between the optical polishing surface and the processing surface. However, by providing the optically polished chamfered portion 21b, the distance between the upper end 23 of the side portion 21a and the substrate can be increased. For example, in the case of the above-described configuration, the distance between the placement surface 13a and the upper end 23 of the side portion 21a is 2 mm. Thereby, even when the board | substrate 14 is test | inspected in the position corresponding to the hole 21, the influence of the upper end 23 of the side part 21a can be reduced.

  With the above-described configuration, the influence of edges can be reduced in an optical system having an NA (numerical aperture) of 0.13 and a magnification of 5 times. Even with such an optical system having a low numerical aperture, it was possible to accurately inspect at the position of the hole 21. Of course, the sizes of the holes 21 and the chamfered portions 21b can be set to appropriate dimensions according to the numerical aperture and magnification of the optical system.

  In FIG. 3, the chamfered portion 21 b has a C chamfer, but may have an R chamfer as shown in FIG. 4. In this case, an R chamfer with a radius of 2 mm can be obtained with the same configuration as described above. Thereby, the distance of the upper end 23 of the side part 21a and the mounting surface 13a can be separated. Further, since the chamfered portion 21b is optically polished, the edge 22 becomes a ridge line between the optically polished surfaces. Therefore, the inspection can be performed without being affected by the edge 22. Furthermore, even when the chamfering is performed, the chamfered portion 21b is inclined downward from the mounting surface, so that the substrate 14 can be mounted horizontally.

  In addition, in the above-mentioned embodiment, although the cross section demonstrated as a circular hole, the cross-sectional shape of a hole is not restricted circularly, For example, a rectangle and a polygon may be sufficient. The present invention is not limited to the through hole, and can be used for a hole provided as a recess from the placement surface 13a. Furthermore, when a stage is comprised from several stand | bases, it is also possible to utilize the above-mentioned in the hole provided in the clearance gap between a stand | base | stand and a stand. Further, the present invention is not limited to the one used for the hole of the support pin for transporting the substrate. Moreover, not only the structure which makes the surface which cross | intersects the mounting surface of a hole be a chamfering part, but the surface which cross | intersects the mounting surface of a hole is made into an optical polishing surface, and edge 22 is made into the ridgeline of optical polishing surfaces. The influence of the edge portion can be reduced.

  In the above-described embodiment, the stage has been described as a stage used in a defect inspection apparatus, but is not limited to a defect inspection apparatus. For example, the present invention can be used for an optical apparatus using a transparent stage such as a microscope, a measuring apparatus, an inspection apparatus, and an observation apparatus. Furthermore, the target object is not limited to the color filter, and can be used for, for example, a transparent photomask or a reticle. In general, a color filter substrate used in a liquid crystal display device has a large target pattern as compared with a photomask for a semiconductor device, and thus has a low numerical aperture and a small numerical aperture. Therefore, the present invention is suitable for the color filter substrate because it is easily affected by the edge portion.

It is a figure which shows the structure of the optical apparatus concerning this invention. It is a figure which shows the structure of the stage for optical apparatuses concerning this invention. It is an expanded sectional view which shows the structure of the stage for optical apparatuses concerning Embodiment 1 of this invention. It is an expanded sectional view which shows a different structure of the stage for optical apparatuses concerning Embodiment 1 of this invention. It is an expanded sectional view which shows the structure of the conventional stage for optical apparatuses.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical apparatus, 11 Light source, 12 Lens, 13 Stage, 13a Mounting surface,
14 substrate, 15 lens, 16 detector, 17 processing device, 18 support pin,
21 hole, 21a side, 21b chamfer, 22 edge, 23 upper end of side

Claims (7)

A mounting surface for mounting a target object, optically polished mounting surface;
A stage for a transparent optical device provided with a hole provided in the mounting surface,
A stage for an optical device, wherein a surface of the hole that intersects the mounting surface is optically polished.   The stage for an optical device according to claim 1, wherein a surface of the hole that intersects the mounting surface is inclined downward from the mounting surface. Further comprising a chamfered portion chamfered on the mounting surface side of the hole,
The stage for an optical device according to claim 1, wherein the chamfered portion and the mounting surface intersect each other.   An optical device comprising the optical device stage according to claim 1. A light source for irradiating the color filter substrate with light;
A detector for detecting light from the light source transmitted through the color filter substrate;
A defect inspection apparatus comprising a transparent stage in which holes are formed on a mounting surface on which the color filter substrate is mounted,
A defect inspection apparatus in which the placement surface and a surface intersecting with the placement surface of the hole are optically polished.   The defect inspection apparatus according to claim 5, wherein a surface that intersects the placement surface of the hole is inclined downward from the placement surface. Further comprising a chamfered portion chamfered on the mounting surface side of the hole,
The defect inspection apparatus according to claim 5 or 6, wherein the chamfered portion and the placement surface intersect each other.

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