JPH11190698A - Defect inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make wide visual field image focusing possible using a small aperture image focusing lens. SOLUTION: A lighting means is constituted using a multiple wavelength light source 1 and a concave reflecting mirror 4c so that a luminous flux angle of illuminating light is smaller than the aperture angle of a detecting lens, that the illuminating light is made to irradiate a specific area on an inspected sample and that each luminous flux of the illuminating light is converged on the vicinity of the pupil of the detecting lens without aberration. An image focusing means is provided with a transmission part 7B not larger than an exit pupil installed near the pupil of the detecting lens 6, and a light shielding part 7A shielding part of transmitted light or reflected light of the illuminating light in the specific area on the detected sample. An image in a linear area focused by the light having passed the transmission part is detected by a one- dimensional or two-dimensional array type detector 8. A signal processing means detects a black defect, a flaw, a foreign matter defect, and the like of the inspected sample on the basis of a detection signal from the one-dimensional or two-dimensional array type detector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect of an electrode pattern or a filter pattern formed on a glass substrate in a process of manufacturing a liquid crystal display, and a defect for detecting whether or not foreign matter is attached to the glass substrate. It relates to an inspection device.

[0002]

2. Description of the Related Art A liquid crystal display (LCD: Liqui)
d Crystal Display) is a CRT (C
Since it can be made thinner and lighter than an Anode Ray Tube, a CTV (Color Tele Tube) can be used.
vision) and OA equipment, etc., and the screen size is increased to 10 inches or more.
Higher definition and colorization are being promoted. The liquid crystal display has a TN (Twisted N)
eMatic) type, STN (Super Twiste)
d Natural) type and TFT (Thin Fil)
m Transistor) type. Among these liquid crystal displays, a color liquid crystal display particularly has a color filter substrate which is patterned corresponding to each pixel electrode. The color filter substrate and the pixel electrode substrate enable color display of a liquid crystal display. The defect inspection apparatus detects various defects (for example, a black defect, a projection defect, a pinhole defect, a color defect defect, a pattern defect, etc.) occurring on the color filter substrate and the pixel electrode substrate. A conventional defect inspection apparatus utilizes the fact that a filter pattern formed on a color filter substrate and an electrode pattern formed on a pixel electrode substrate have a repetitive property (periodicity). Various defects are detected based on the data. Some defect inspection devices use, for example, a spatial filtering method. This utilizes the characteristic that scattered light from a regular pattern on a glass substrate is shielded by a light-shielding portion of a spatial filter, and that diffracted light from a defect passes through the spatial filter and forms an image. Others use an optical Fourier transform system as a kind of pattern discriminator.

[0003]

Generally, a defect inspection apparatus using a diffraction phenomenon forms a wide field of view on a glass substrate at a time because parallel light of monochromatic light is used as illumination light. Is difficult. Therefore, in order to collectively image a wide field of view, a large-diameter imaging lens is required, resulting in a problem that the cost of the optical system is increased. In addition, as the size of the liquid crystal display increases, the size of the glass substrate is changed from 300 × 400 mm to 360 × 460 mm to 370 ×, which can take four 10-inch class panels.
470mm, and currently inspects glass substrates of size 550 x 650mm or more, which can take 10.4-12.1-inch class panels on 6 sides or 15-inch class panels on 2 sides. It is a proposition to do it at high speed. When the size of the glass substrate is increased as described above, there is a problem that it takes too much time to inspect for defects by using a conventional imaging optical system having a small visual field. In order to shorten the inspection time, a large-diameter imaging lens that can collectively image a wide field of view on a glass substrate may be used, but such an optical system is very expensive, so the inspection apparatus There is a problem that the cost of the device itself is increased, which is not preferable from the viewpoint of cost reduction. The present invention has been made in view of the above points, and an object of the present invention is to provide a low-cost defect inspection apparatus that enables wide-field imaging using a small-diameter imaging lens.

[0004]

According to a first aspect of the present invention, there is provided a defect inspection apparatus for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and irradiating the sample to be inspected with light. Imaging the transmitted light or reflected light of the illumination light using an imaging lens, an image forming means for detecting the image with a one-dimensional array detector, and processing a signal output from the detector,
A defect inspection apparatus for a specimen to be inspected, comprising: signal processing means for detecting a defect on the specimen to be inspected; and sample transport means for transporting the specimen to be inspected in a predetermined direction. The light is composed of a light beam converging at each point on the sample to be inspected, and the concave reflecting mirror is a beam angle which is a maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected. Are configured to be smaller than the aperture angle of the imaging lens, so that the illumination light irradiates a region including a linear region on the sample to be inspected, and each of the light beams of the illumination light The imaging unit is configured to converge without aberration near the pupil of the image lens, and the imaging unit includes a transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the imaging lens; The illumination in the linear region above A light-shielding portion that shields a part of transmitted light or reflected light of light, wherein the one-dimensional array-type detector detects an image of a linear region formed by light passing through the light-transmitting portion; The processing unit detects a defect of the sample to be inspected based on a detection signal from the one-dimensional array type detector, and the sample transporting unit detects a defect in a longitudinal direction of the linear region irradiated by the illumination light. The test sample is transported continuously in a vertical direction. In the defect inspection apparatus according to the first invention, the illumination light applied to the surface of the sample to be inspected by the illuminating means normally passes through the sample to be inspected when there is no defect on the surface of the sample to be inspected. Or is reflected normally on the surface of the sample to be inspected. However, when a black defect, a scratch or a foreign matter defect is present on the surface of the sample to be inspected, the illumination light is attenuated, scattered, or deflected according to the defect. Of the light reflected, transmitted, scattered, and deflected on the surface of the sample to be inspected, light within a range smaller than the aperture angle of the imaging lens is taken into the imaging lens. When the light-shielding part blocks normal reflected light or transmitted light in the light taken into the imaging means, the scattered and deflected extraordinary light passes through the transmission part and forms an image on the one-dimensional array type detector. . Conversely, when the light shielding unit blocks the scattered or deflected abnormal light in the light taken into the imaging means, normal reflected light or transmitted light passes through the transmission unit and passes to the one-dimensional array type detector. Form an image. Therefore, the signal processing means can detect a defect such as a black defect and a scratch / foreign matter defect of the sample to be inspected based on the output from the one-dimensional array type detector. In addition, in the first invention, since the inspection is performed by the one-dimensional array detector, the first invention has a transport unit that transports the sample to be inspected in a direction perpendicular to the longitudinal direction of the one-dimensional array detector.

According to a second aspect of the present invention, there is provided a defect inspection apparatus comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror; and a transmitted light of the illumination light illuminating the inspection sample. An image forming means for forming an image of reflected light by using an image forming lens and detecting the image with a one-dimensional array type detector;
A signal processing unit configured to process a signal output from the two-dimensional array detector and display a defect on the sample to be visually inspected; and a sample transport unit configured to transport the sample to be inspected in a predetermined direction. A defect inspection apparatus for a sample to be inspected,
The illuminating light of the illuminating means is composed of a light beam converging at each point on the sample to be inspected, and the concave reflecting mirror has a maximum luminous flux of the illuminating light incident or emitted at each point on the sample to be inspected. The luminous flux angle, which is a cone angle, is configured to be smaller than the opening angle of the imaging lens, the illumination light irradiates a region including a linear region on the test sample, and the illumination light Each of the light beams is configured to converge without aberration near the pupil of the imaging lens, and the imaging unit includes a transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the imaging lens. And a light-shielding portion that shields a part of the transmitted light or reflected light of the illumination light in the linear region on the sample to be inspected, and a linear region formed by light passing through the transparent portion. The image is detected by the one-dimensional array type detector, and The display means displays a defect of the sample to be inspected based on a detection signal from the one-dimensional array type detector so that the defect can be distinguished. And continuously transports the sample to be inspected in a direction perpendicular to the sample. The defect inspection apparatus according to the second invention has display means for processing an image signal detected by the one-dimensional array type detector and displaying it in a visually recognizable manner. A defect or a defect such as a scratch / foreign matter defect is displayed so as to be distinguishable.

According to a third aspect of the present invention, there is provided a defect inspection apparatus comprising: an illuminating means for irradiating illumination light from a light source to a specimen using a concave reflecting mirror; and an illumination light illuminating the inspection specimen by the illumination means. Imaging means for imaging transmitted light or reflected light by an imaging lens and detecting the image with a two-dimensional array type detector, and processing a signal output from the two-dimensional array type detector, A defect processing apparatus for inspecting a sample to be inspected, comprising: signal processing means for detecting a defect on the sample to be inspected; wherein the illumination light of the illumination means comprises a light beam converging at each point on the sample to be inspected. The concave reflecting mirror is configured such that a light beam angle, which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than an opening angle of the imaging lens. The illumination light is the sample to be inspected Are arranged so that each of the luminous fluxes of the illumination light converges near the pupil of the imaging lens without aberration. A transmission unit having a size equal to or smaller than an exit pupil installed near the pupil, and a light-shielding unit that shields a part of transmitted light or reflected light of the illumination light in the planar area on the test sample, The two-dimensional array type detector detects an image of a planar area formed by the light passing through the transmitting part, and the signal processing means detects the image based on a detection signal from the two-dimensional array type detector. This is to detect a defect of the inspection sample. In the defect inspection apparatus according to the third aspect of the invention, the illuminating means is configured to irradiate the planar area of the sample to be inspected, and the imaging means is also capable of detecting a planar image. It is composed of Based on the image signal detected by the two-dimensional array type detector, a defect such as a black defect or a scratch / foreign matter defect of the sample to be inspected is detected.

According to a fourth aspect of the present invention, there is provided a defect inspection apparatus comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror; and an illumination light illuminating the inspection sample by the illumination means. A defect inspection apparatus that forms transmitted light or reflected light by an imaging lens and displays the image on a screen, wherein the illumination light of the illumination unit converges at each point on the sample to be inspected. And the concave reflecting mirror comprises:
The luminous flux angle, which is the maximum cone angle of the luminous flux of the illumination light incident or emitted at each point on the specimen, is configured to be smaller than the opening angle of the imaging lens, and the illumination light is The illumination device is configured to irradiate a planar region on a sample, and each of the luminous fluxes of the illumination light is condensed near the pupil of the imaging lens without aberration. A transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the lens, and a light-shielding unit that shields a part of transmitted light or reflected light of the illumination light in the planar region on the test sample. Forming an image of a planar area formed by light passing through the transmitting portion on a screen,
The defect of the sample to be inspected is made visible based on the image on the screen. In the defect inspection apparatus according to the fourth aspect of the invention, the illuminating means is configured to irradiate a planar region of the sample to be inspected, and the imaging means responds to a black defect or a scratch / foreign matter defect of the sample to be inspected. The resulting image is displayed on the screen.

According to a fifth aspect of the present invention, there is provided a defect inspection apparatus comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror; and an illumination light illuminating the inspection sample by the illumination means. Imaging means for imaging transmitted light or reflected light by an imaging lens and detecting the image with a two-dimensional array type detector, and processing a signal output from the two-dimensional array type detector, A display means for visually displaying a defect on the inspection sample, wherein the illumination light of the illumination means converges at each point on the inspection sample. And the concave reflecting mirror is configured such that a light beam angle, which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the inspection sample, is smaller than an opening angle of the imaging lens. Wherein the illumination light is The illumination device is configured to irradiate a planar region on a sample, and each of the luminous fluxes of the illumination light is condensed near the pupil of the imaging lens without aberration. A transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the lens, and a light-shielding unit that shields a part of transmitted light or reflected light of the illumination light in the planar region on the test sample. Detecting an image of a planar area formed by the light passing through the transmission unit with the two-dimensional array detector, and displaying the image based on a detection signal from the two-dimensional array detector. The defect of the sample to be inspected is displayed in a distinguishable manner. The defect inspection apparatus according to the fifth aspect of the invention has display means such as a monitor for processing an image signal detected by the two-dimensional array detector and displaying the processed image signal visually. A black defect or a scratch / foreign matter defect of the sample is displayed so as to be distinguishable.

A defect inspection apparatus according to a sixth aspect of the present invention is an illumination device for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and transmitted light of the illumination light illuminating the sample to be inspected. Alternatively, the reflected light is imaged using an imaging lens, and the image is detected by a one-dimensional array type detector, and a signal output from the detector is processed to form an image on the sample to be inspected. A defect inspection apparatus for a sample to be inspected, comprising: a signal processing unit for detecting a defect; and a sample transporting unit for transporting the sample to be inspected in a predetermined direction, wherein the illumination light of the illumination unit emits the sample to be inspected. The concave reflecting mirror is constituted by a light beam angle which is the maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected. It is configured to be smaller than the opening angle, The illumination light irradiates an area including a linear area longer than the aperture of the imaging lens on the sample to be inspected, and each of the light beams of the illumination light has no aberration near the pupil of the imaging lens. The imaging unit is configured to collect light, and the imaging unit includes a transmission unit having a size equal to or smaller than an exit pupil installed near a pupil of the imaging lens, and the transmission unit in the linear region on the sample to be inspected. A light-shielding portion that shields a part of the transmitted light or the reflected light of the illumination light, and detects the image of the linear region formed by the light that has passed through the transmission portion with the one-dimensional array type detector, The signal processing unit detects a defect of the inspection sample based on a detection signal from the one-dimensional array type detector, and the sample transporting unit detects a defect in a longitudinal direction of the linear region irradiated by the illumination light. Continually transports the test sample in a vertical direction By Rukoto,
It is to inspect various defects on the sample to be inspected in a region wider than the aperture of the imaging lens. The defect inspection apparatus according to a sixth aspect of the present invention is the defect inspection apparatus according to the first aspect, wherein the illuminating means irradiates the illumination light onto an area including a linear area longer than the aperture of the imaging lens on the sample to be inspected. And inspects various defects on the sample to be inspected over an area wider than the aperture of the imaging lens. That is, the aperture is configured to increase in the order of the aperture of the imaging lens, the length of the linear region on the sample to be inspected, and the aperture of the illumination lens. As a result, it is possible to inspect a defect on a specimen to be inspected over a wider area by using an imaging lens having a small diameter.

[0010] A defect inspection apparatus according to a seventh aspect of the present invention is an illumination device for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and transmitted light of the illumination light applied to the sample to be inspected. Alternatively, the reflected light is imaged using an imaging lens, and the image is detected by a one-dimensional array type detector, and a signal output from the detector is processed to form an image on the sample to be inspected. A defect inspection apparatus for a specimen to be inspected, comprising: display means for visually displaying a defect; and sample transport means for transporting the specimen in a predetermined direction, wherein the illumination light of the illumination means is illuminated by the illumination light. The concave reflecting mirror is formed by a light beam angle which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the inspection sample. Configured to be smaller than lens aperture angle The illumination light irradiates an area including a linear area longer than the aperture of the imaging lens on the sample to be inspected, and each of the light fluxes of the illumination light is near a pupil of the imaging lens. The imaging unit is configured to collect light without aberration, and the imaging unit includes a transmission unit having a size equal to or smaller than an exit pupil provided near a pupil of the imaging lens, and the linear region on the sample to be inspected. A light-shielding portion that shields a part of the transmitted light or the reflected light of the illumination light, and converts the image of the linear region formed by the light that has passed through the transparent portion into the first region.
Detected by a two-dimensional array type detector, and the display means
The defect of the sample to be inspected is displayed so as to be distinguishable based on a signal from the two-dimensional array type detector, and the sample transport means is arranged in a direction perpendicular to a longitudinal direction of the linear region irradiated by the illumination light. By continuously transporting the sample to be inspected, various defects on the sample to be inspected are inspected over an area wider than the aperture of the imaging lens.
The defect inspection apparatus according to a seventh aspect of the present invention is the defect inspection apparatus according to the second aspect, wherein the illuminating means irradiates the illumination light on an area including a linear area longer than the diameter of the imaging lens on the inspection sample. And inspects various defects on the sample to be inspected over an area wider than the aperture of the imaging lens.

According to an eighth aspect of the present invention, there is provided a defect inspection apparatus, comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror; and transmitted light of the illumination light illuminating the sample to be inspected. Alternatively, the reflected light is imaged using an image forming lens, and an image forming means for detecting the image with a two-dimensional array type detector, and a signal output from the detector is processed to form an image on the sample to be inspected. A defect inspection apparatus for inspecting a specimen, comprising: signal processing means for detecting a defect; wherein the illumination light of the illumination means comprises a light beam converging at each point on the specimen, The mirror is configured such that the light beam angle, which is the maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than the opening angle of the imaging lens, and the illumination light is Diameter of the imaging lens on the sample to be inspected The illumination device is configured to irradiate a large planar area, and each of the light beams of the illumination light is focused without aberration near a pupil of the imaging lens. A transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the lens, and a light-shielding unit that shields a part of transmitted light or reflected light of the illumination light in the planar region on the test sample. Detecting an image of a planar region formed by the light passing through the transmitting portion with the two-dimensional array detector, and the signal processing means detects the image based on a detection signal from the two-dimensional array detector. It detects a defect on the sample to be inspected in a region wider than the aperture of the imaging lens. The defect inspection apparatus according to an eighth aspect of the present invention is the defect inspection apparatus according to the third aspect, wherein the illuminating means irradiates the illumination light onto a planar area wider than the aperture of the imaging lens on the inspection sample. It is configured to inspect various defects on the sample to be inspected over a region wider than the aperture of the imaging lens.

According to a ninth aspect of the present invention, there is provided a defect inspection apparatus comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror; A defect inspection apparatus that forms an image of reflected light with an imaging lens and displays the image on a two-dimensional screen, wherein the illumination light of the illumination unit includes a light beam converging at each point on the sample to be inspected. The concave reflecting mirror is configured such that a light beam angle, which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than an opening angle of the imaging lens. The illumination light illuminates a planar area on the sample to be inspected that is wider than the aperture of the imaging lens, and each of the luminous fluxes of the illumination light condenses near the pupil of the imaging lens without aberration. And the connection The means includes a transmitting portion having a size equal to or smaller than an exit pupil provided in the vicinity of a pupil of the imaging lens, and blocking a part of transmitted light or reflected light of the illumination light in the linear region on the test sample. And a light-shielding portion that forms an image of a planar region formed by light passing through the transmission portion on the screen, and allows a defect of the sample to be inspected to be visually observed based on the image on the screen. It is configured as described above. The defect inspection apparatus according to the ninth invention has a
In the defect inspection apparatus according to the invention, the illuminating means is configured to irradiate the illumination light onto a planar area larger than the aperture of the imaging lens on the sample to be inspected, and the area larger than the aperture of the imaging lens. In this way, various kinds of defects on the sample to be inspected are inspected.

According to a tenth aspect of the present invention, there is provided a defect inspection apparatus, comprising: an illuminating means for irradiating illumination light from a light source to a sample to be inspected by using a concave reflecting mirror; Imaging means for imaging the reflected light with an imaging lens and detecting the image with a two-dimensional array detector, and processing signals output from the detector to visually recognize defects on the sample to be inspected A defect inspecting apparatus for inspecting the specimen, the illumination light being provided by the illuminating means being constituted by a light beam converging at each point on the specimen, wherein the concave reflecting mirror is provided. Is configured such that the light beam angle, which is the maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than the opening angle of the imaging lens, and the illumination light is From the aperture of the imaging lens on the sample to be inspected Also be configured to illuminate a large surface area, each light beam of the illumination light is configured to aberration without condensed near the pupil of the imaging lens,
The image forming means includes a transmitting portion having a size equal to or smaller than an exit pupil provided in the vicinity of a pupil of the image forming lens, and transmitting light or reflected light of the illumination light in the planar area on the sample to be inspected. A light-shielding portion that shields a portion, wherein the two-dimensional array-type detector detects an image of a planar area formed by light passing through the transmission portion, and the display unit detects the two-dimensional array-type detection. A defect of the sample to be inspected in a region wider than the aperture of the imaging lens is displayed so as to be distinguishable based on a detection signal from a container. The defect inspection apparatus according to the tenth invention is the defect inspection apparatus according to the fifth invention,
The illuminating means is configured to irradiate illumination light onto a planar area wider than the aperture of the imaging lens on the sample to be inspected. It is configured to inspect for defects.

According to an eleventh aspect of the present invention, there is provided a defect inspection apparatus comprising:
In the defect inspection apparatus according to any one of the inventions, the light-shielding portion may transmit light or reflected light of the transmitted light or reflected light of the test sample that is normally transmitted or reflected by the test sample. It is characterized in that the light is shielded and the transmitting portion guides scattered light or deflected light caused by a defect on the surface of the sample to be inspected to the one-dimensional array type detector or the two-dimensional array type detector. In the defect inspection apparatus according to the eleventh aspect, the light-shielding portion blocks normal reflected light or transmitted light in the light taken into the imaging means, and scattered and deflected abnormal light passes through the transmission portion to be one-dimensional. This defines the case where an image is formed on an array type detector or a two-dimensional array type detector.

The defect inspection apparatus according to the twelfth invention has a first
In the defect inspection apparatus according to any one of the first to tenth aspects of the present invention, the light-shielding portion may be scattered light or deflected light of transmitted light or reflected light of the sample to be inspected due to a defect on the surface of the sample to be inspected. And the transmitting section guides the light that has normally transmitted or reflected the test sample to the one-dimensional array type detector or the two-dimensional array type detector. In the defect inspection apparatus according to the twelfth aspect, the light-shielding portion is scattered in the light captured by the imaging means,
The case is defined in which the deflected abnormal light is blocked, and normal reflected light or transmitted light passes through the transmission part and forms an image on the one-dimensional array detector or the one-dimensional array detector.

[0016]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a diagram showing a schematic configuration of a defect inspection apparatus according to the first embodiment for detecting a defect or foreign matter on a color filter substrate and a pixel electrode substrate of a liquid crystal display. This defect inspection apparatus detects the presence or absence of a flaw or foreign matter defect from a sample to be inspected (a color filter substrate, a pixel electrode substrate, or the like) by an inspection optical system described later.

First, the defect inspection apparatus holds a sample to be inspected by the sample transport section 21 and transports it in a predetermined direction. X for detecting the position of the sample is provided in the sample transport unit 21.
-It has a Y-axis encoder 22. The XY axis encoder 22 detects a relative position of the sample to be inspected on the XY axis based on a scale provided on a side surface of the sample transport unit 21. The detector drive circuit 23 drives the scattered light deflection light detector 28, the A / D converter 29, the determination circuit 2A, and the scratch / foreign matter defect memory 2B based on the X-axis coordinate signal from the XY axis encoder 22. Control. The scattered light polarized light detector 28 is constituted by a one-dimensional array type detector.

A scattered light deflection light detector 28 detects an image formed by light scattered or deflected by a scratch or foreign matter on the sample to be inspected, and outputs a detection signal V 1 to an A / D converter 29. The A / D converter 29 converts the detection signal V1 into a digital signal and outputs the digital signal to the determination circuit 2A. Judgment circuit 2A
Determines whether the detection signal V1 is greater than a predetermined value, and outputs a signal indicating the determination result to the scratch / foreign matter defect memory 2B.
Output to In the case where a repetitive pattern or a directional pattern is formed on the sample 5 to be inspected, the influence of the pattern is reduced by using a difference image circuit corresponding to the adjacent pattern comparison processing method in the determination circuit 2A. The minute pattern defect may be detected by removing it. The flaw / foreign matter defect memory 2B stores a signal indicating the result of the determination by the determination circuit 2A using the coordinate signals X and Y from the XY axis encoder 22 as addresses. When the processing for the predetermined coordinate signal Y is completed, this coordinate signal is incremented,
Similar processing is repeatedly executed to obtain defect information corresponding to the entire surface of the sample 5 to be inspected in FIGS. 1A and 1B. The microprocessor unit (MPU) 2C
Based on a signal from the flaw / foreign matter defect memory 2B, the flaw / foreign matter defect of the sample to be inspected is determined, converted into displayable data, and output to the display 2D. The display 2D is M
It is a display panel that displays display data from the PU2C so as to be visible.

FIGS. 1A and 1B show the sample transfer section 2 of FIG.
FIG. 1A is a diagram showing the configuration of each optical system with respect to a sample 5 to be inspected held in FIG. 1, FIG. 1A is a diagram of the optical system viewed from a + Y-axis direction, and FIG. 1B is a diagram of the optical system viewed from a + X-axis direction. It is. In this embodiment, the sample 5 to be inspected is inspected by the transmitted light. 1A and 1
In B, the optical system includes an illumination unit and an imaging unit. The illumination means includes a multi-wavelength light source 1, a condenser lens 2, a slit diaphragm 3, an auxiliary condenser lens 4A, an illumination diaphragm 33, a half mirror 4B, and a concave reflecting mirror 4C. When an attempt is made to illuminate a large-area inspection sample 5 using a conventional condenser lens composed of a large-diameter convex lens without using a concave reflecting mirror, due to the spherical aberration of the large-diameter convex lens, it is difficult to illuminate the vicinity of the imaging lens. A large blur occurs in the collection of illumination, and the detection sensitivity is reduced. When the concave reflecting mirror 4C is used, no spherical aberration occurs, and the detection sensitivity is improved. The imaging means includes a detection lens group 6 and a light shielding plate 7. One-dimensional array detector 8
Corresponds to the scattered light deflection light detector 28 in FIG.

The multi-wavelength light source 1 outputs a white light beam, and a halogen lamp or the like is used. this is,
This is because, in the thin film sample 5 on an LSI Si wafer or the like, thin-film interference due to monochromatic light due to a slight variation in the thickness of the thin film occurs, and this becomes noise, so that conventional laser illumination cannot be applied. Conventional laser illumination cannot be used even when a mosaic RGB color is formed on the sample 5 such as an LCD color filter. For example, R
This is because, when the respective colors of the GB pattern are transmitted and illuminated, if the red laser is used to illuminate, the R pattern portion has sensitivity but the G pattern and B pattern have no sensitivity. Therefore, if white light illumination is used, the thin film interference effect can be reduced.
Each of the GB patterns also has sensitivity. But,
If a large-diameter convex lens is used as an illumination condenser lens for a large-area sample inspection, chromatic aberration occurs, and the convergence of illumination is largely blurred near the pupil position of the imaging lens, and the detection sensitivity is reduced. If there is no thin film or color filter on the surface of the sample 5, a multi-wavelength light source is not necessary, and therefore, a single-mode or multi-mode semiconductor laser, gas laser, ultra-high pressure mercury lamp, or the like can be used as the multi-wavelength light source 1. Even in this case, when the sample 5 has a large area, use of a large-aperture lens for the condenser 4C causes spherical aberration, and condensed illumination is largely blurred near the pupil position of the imaging lens, thereby lowering the detection sensitivity. I do. Then, if the aberration is removed by using the concave reflecting mirror 4C, blurring of the two can be prevented, the illumination can be efficiently collected, and the detection sensitivity can be improved.

The condensing lens 2 condenses the light beam of the multi-wavelength light source 1 on the front focal position (position of the slit stop 3) of the auxiliary condensing lens 4A. The substantially parallel light beam that has passed through the auxiliary condenser lens 4 </ b> A is located at the position of the illumination stop 33 at the optical axis (not shown) of the illumination system.
Intersects with the concave reflecting mirror 4C. Here, the stop 33 is a pupil of the illumination system and determines the luminous flux angle θ of the light incident on the sample 5 to be inspected. The slit diaphragm 3 has an elongated slit along the Z-axis direction, and has a shape such that a light beam from the multi-wavelength light source 1 irradiates an area on the sample 5 to be inspected including an elongated linear area in the X-axis direction. I have. The auxiliary condenser lens 4A, the illumination stop 33, the half mirror 4B, and the concave reflecting mirror 4C are light beams passing through the slits S (A1 to B1) of the slit stop 3, that is, the slits S of the slit stop 3.
Is formed on the surface of the inspection area 5 as an image A2. In FIG. 1B, a multi-wavelength light source 1, a condenser lens 2,
The illustration of the illumination stop 33 and the auxiliary condenser lens 4A is omitted, and the slit stop 3 and the slit S are shown by dotted lines.

The detection lens group 6 converts an image A2 of a linear region corresponding to the shape of the slit S of the slit stop 3 formed on the surface of the sample 5 to be inspected into a rear focal position of the detection lens group 6, that is, one-dimensionally. An image is formed on the surface of the array type detector 8 as an image A3. When the image A2 of the linear area of the slit stop 3 formed on the surface of the sample 5 to be inspected is scattered or deflected on the surface of the sample 5 to be inspected, the scattered light and the deflected light are taken into the detection lens group 6. Image A on the surface of the one-dimensional array detector 8
3 is formed. The detection lens group 6 includes a plurality of plano-convex lenses and a biconvex lens.

However, in this embodiment, the position of the pupil (exit pupil) of the detection lens group 6, that is, the condensing position of the concave reflecting mirror 4C (the position intersecting with the optical axis of the detection system (not shown)) is set. A light-shielding plate 7 having a small-diameter light-shielding portion 7A for shielding light (direct light) not scattered or deflected on the surface of the sample 5 is provided. Therefore, light (direct light) that has not been scattered or deflected on the surface of the sample 5 to be inspected is blocked by the light shielding portion 7A of the light shielding plate 7 and does not form an image on the surface of the one-dimensional array type detector 8. Only the light scattered or deflected on the surface of the test sample 5 is transmitted to the annular light transmitting portion 7 of the light shielding plate 7.
After passing through B, an image is formed on the surface of the one-dimensional array type detector 8. Note that the detection lens group 6 is composed of a plurality of lens groups, an example of which is shown, and it goes without saying that the detection lens group 6 may be composed of a combination of other lens groups.

Since the light-shielding portion 7A of the light-shielding plate 7 has a light-shielding portion 7C constituting a stop around the light-shielding portion 7A, the opening angle of the detection lens group 6 is θ0. The illumination light of the illuminating means is composed of a light flux converging at each point on the sample 5 to be inspected, and is the maximum cone angle of the light beam of the illumination light which is incident on the sample 5 to be inspected from the illumination means or emitted from the sample 5. Some luminous flux angles are θ
Here, the opening angle θ0 of the detection lens group 6 is set to be larger than the light beam angle θ. Accordingly, of the light scattered or changed on the surface of the inspection object 5, only the light beam passing through the ring-shaped light passing portion 7 B within the opening angle θ 0 is taken into the imaging means, and the surface of the one-dimensional array type detector 8 is Image. That is, the opening angle θ0
Can be changed by appropriately adjusting the size of the outer diameter of the ring-shaped light transmitting portion 7B of the light shielding plate 7. The other image B1 of the slit diaphragm 3 is formed as an image B2 on the surface of the inspection area 5 on the opposite side with the optical axis symmetrical, and further, the image B1 is formed on the surface of the one-dimensional array type detector 8.
An image is formed as 3, but an auxiliary line indicating the state is omitted in FIG.

FIG. 1C is a conceptual diagram showing a case where the concave reflecting mirror 4C shown in FIGS. 1A and 1B is replaced by a convex lens 4C1 having a focal length f. In FIG. 1C, the illumination diaphragm 33 is located at the front focal length of the convex lens 4C1, and the test sample 5 is located at the rear focal length of the convex lens 4C1. The illumination stop 33 corresponds to a position 70 which is twice the focal length of the convex lens 4C1. The light condensing at the position 70 is the light condensing on the lens pupil position 7 by the action of the imaging lens 6. (The illumination system diaphragm 33 is used as the detection system diaphragm 7 (7
0). ). The same relationship is applied to the concave reflecting mirror 4C in FIGS. 1A and 1B. Therefore,
The substantially parallel light beam that has passed through the illumination stop 33 is a concave reflecting mirror 4C.
At the position of the light-shielding plate 7 (pupil of the detection lens group 6) and intersects the optical axis of the detection system. FIG.
In FIG. 1A and FIG. 1B, the light-shielding plate 7 is arranged at this intersection position.

FIGS. 3A and 3B are diagrams showing the schematic configuration of each optical system of the defect inspection apparatus according to the second embodiment, similarly to FIGS. 1A and 1B. 3A and 3B, the same components as those in FIGS. 1A and 1B are denoted by the same reference numerals, and a description thereof will be omitted. 3A and 3B
Is different from the embodiment of FIGS. 1A and 1B in that
The point is that the shape of the slit diaphragm 3A is square (two-dimensional), and the shape of the two-dimensional array type detector 8A is also square (two-dimensional) accordingly. Thus, the slit aperture 3A and the two-dimensional array sensor 8
1A and 1B since A is two-dimensionally configured.
Since the defect inspection of a sufficiently large area can be performed without performing the scanning process in the Y-axis direction unlike the defect inspection apparatus of the above, the time required for the defect inspection of the entire surface of the sample 5 to be inspected is greatly reduced. It can be reduced.

FIGS. 4A and 4B are diagrams showing the schematic configuration of each optical system, similarly to FIGS. 1A and 1B. In FIG. 4A, illustration of the multi-wavelength light source 1, the condenser lens 2, the slit diaphragm 3, and the auxiliary condenser lens 4A of FIG. 1A is omitted. 1A and 1B in FIGS. 4A and 4B.
Since components having the same configuration as B are denoted by the same reference numerals,
The description is omitted. However, lower portions of the concave reflecting mirror 4D and the half mirror 4B are omitted. FIG.
4A and FIG. 4B is different from those of FIGS. 1A and 1B in that the length L (A2-B2) of the image of the slit diaphragm 3B formed on the surface of the sample 5 to be inspected is different from the detection lens group 6A.
Is as large as or larger than the diameter Dφ of
Further, the slit SB of the slit stop 3B is longer than the slit S of the slit stop 3 of FIG. 1, the concave reflecting mirror 4D is sufficiently larger than the concave reflecting mirror 4C of FIGS. 1A and 1B, and the detection lens group 6A is formed of FIGS. 1B is different from the combination of a plurality of lenses shown in FIG. 1B. It goes without saying that the detection lens group 6A may be configured by a combination of other lenses. In this manner, by increasing the diameter of the slit SB of the slit diaphragm 3B and the diameter of the concave reflecting mirror 4D and using a normal aperture for the detection lens group 6A, the area to be inspected of the specimen 5 to be inspected, that is, the slit diaphragm 3B Since the linear illumination area to be formed can be enlarged, the inspection area by one scanning in the X direction can be greatly improved, so that the inspection time can be shortened, that is, the defect inspection time of the specimen 5 can be reduced. The time required can be greatly reduced.

FIG. 4C is a conceptual diagram showing a case where the concave reflecting mirror 4D of FIGS. 4A and 4B is replaced by a convex lens 4C2. In FIG. 4C, the illumination stop 33 is a convex lens 4.
The test sample 5 is provided at a position on the front side of C2, which is approximately twice as long as the focal length, and the test sample 5 is located at the rear focal length of the convex lens 4C2. The illumination diaphragm 33 is a convex lens 4C2
Corresponds to a position 70 which is twice the focal length. The same relation is applied to the concave reflecting mirror 4D of FIGS. 4A and 4B. Therefore, the substantially parallel light beam that has passed through the illumination diaphragm 33 is reflected by the concave reflecting mirror 4D, is condensed on the surface of the sample 5 to be inspected, and is located at the position of the light shielding plate 7 (the pupil of the detection lens group 6). Intersect. 4A and 4B, the light shielding plate 7 is arranged at the intersection.

FIGS. 5A and 5B are diagrams showing the schematic configuration of each optical system as in FIGS. 1A and 1B. 5A and 5B, the same components as those in FIGS. 1A and 1B are denoted by the same reference numerals, and a description thereof will be omitted. In FIG. 5B, the multi-wavelength light source 1, the condenser lens 2, the auxiliary condenser lens 4A, and the illumination stop 33 are omitted. 5A and 5B is different from that of FIGS. 1A and 1B in that a light shielding plate 71 is provided at a pupil position inside the detection lens group 6B.
Is provided. Here, the pupil diameter of the lens group 6B is the same as the inner diameter Cφ of the light shielding portion 7C of the light shielding plate 71. The detection lens group 6B is a modification of the one in FIG. 1, and its basic operation is hardly changed. The one-dimensional array type detector 8 is provided corresponding to the longitudinal direction of the linear illumination region formed on the surface of the sample 5 to be inspected, and receives light scattered or deflected on the surface of the sample 5 to be inspected. The scattered light deflection light detector 28.

FIGS. 6A and 6B are diagrams showing a schematic configuration of each optical system, similarly to FIGS. 4A and 4B. 6A and 6B, the same components as those in FIGS. 4A and 4B are denoted by the same reference numerals, and the description thereof will be omitted. 6A and 6B, the one-dimensional array detector 8 is omitted. The point that the defect inspection apparatus according to the embodiment of FIGS. 6A and 6B differs from that of FIGS. 4A and 4B is that the condensing position of the concave reflecting mirror 4C is located in front of the detection lens group 6C. That is, the light shielding plate 72 is disposed at the light condensing position. By arranging the light shielding plate 72 in front of the detection lens group 6C in this manner, light that has not been scattered or deflected on the surface of the sample 5 to be inspected, that is, direct light, does not enter the detection lens group 6C. Unnecessary stray light (noise) or the like on the lens surface in the detection lens group 6C, which is generated when direct light is incident on the detection lens group 6C, is not generated. It is possible to detect only the scattered or deflected light scattered or deflected with high accuracy without noise. Further, by arranging the light shielding plate 72 outside the detection lens group 6C, it is possible to simplify the manufacture and arrangement of the light shielding plate 72.

FIG. 7 is a diagram schematically showing an output waveform of the scattered light polarized light detector 28 in FIG. 2 in the surface state of the sample 5 to be inspected. In the convex portion 91, the output V1 of the scattered light deflection light detector 28 increases according to the shape of the convex portion 91. Wound 9
2. Similarly, the output V1 of the scattered light deflected light detector 28 also increases in the foreign matter attaching portion 93 and the uneven portion 94 according to the defect shape. On the other hand, when a defect such as a black portion 95 in a thin film shape whose transmittance or reflectance is different from normal exists on the sample to be inspected, scattered light or polarized light is not generated in that portion,
The fluctuation of the output V1 of the scattered light deflection light detector 28 is weak. Since the output V1 is obtained according to the shape of each defect in this manner, it is possible to recognize a defect occurring in the inspection sample based on the output V1.

FIG. 8 is a diagram showing two methods of a defect detection method according to the defect inspection apparatus according to the present invention. FIG.
(A) relates to the optical systems shown in FIGS. 1A, 1B, 3A, 3B, 4A, 4B, 5A, 5B, 6A, and 6B, respectively. This is a transmission detection method applicable when it is made of a transmission material. In this transmission detection method, the light beam from the illumination
, And the transmitted light is imaged by the image forming means 82. On the other hand, when the sample to be inspected is made of an opaque material, that is, a reflective material, the defect inspection of the sample to be inspected 5A is performed by a reflection detection method as shown in FIG. In the case of this reflection detection method, the light beam from the illumination means 81 is irradiated onto the sample 5A to be inspected, and the reflected light is imaged by the imaging means 82. FIGS. 8B to 8D are diagrams schematically showing how an illumination light beam transmits through a sample to be inspected in the transmission detection method, and schematically shows a light beam near the optical axis. FIG. 8B shows a case where the sample to be inspected is normal. The illumination light beam passes through the sample to be inspected while maintaining its incident angle, and enters the imaging means 82. FIG. 8C shows a case where the sample to be inspected has an uneven defect portion. The illumination light flux is transmitted through the uneven defect portion at an angle different from the incident angle and is incident on the imaging means 82. FIG. 8D shows a case where a defect (foreign matter) defect exists in the sample to be inspected.
Each part of the defect is scattered in a complicated manner, and a part of the scattered light enters the imaging means 82. FIGS. 8F to 8H are diagrams schematically showing how an illumination light beam is reflected from an object to be inspected in the reflection detection method, and a light beam near the optical axis thereof. FIG. 8F shows a case where the sample to be inspected is normal. The illumination light beam is reflected by the sample to be inspected while maintaining its incident angle, and is incident on the imaging means 82. FIG. 8 (G) shows a case where an unevenness defect is present in the sample to be inspected. The illumination light beam is reflected at the unevenness defect at an angle different from the incident angle, and is incident on the imaging means 82. FIG. 8H shows a case where a defect (foreign matter) defect exists in the sample to be inspected. The illumination light flux is complicatedly irregularly reflected (scattered) at each part of the defect (foreign matter), and a part of the reflected light is reflected. The light enters the image forming means 82. The components detected by the transmission detection method include a semiconductor photomask, an LCD electrode substrate, an LCD color filter substrate, a disk glass substrate, a semiconductor photomask substrate, and an LCD.
Polarizing plate for LCD, and retardation plate for LCD and STN. In addition, BGA (Ball Grid Array Substrate), Si wafer for semiconductor, PD
There are a substrate for P and an Al substrate for disks.

FIG. 9 is a view showing a modified example of the light shielding plate 7, and shows a shape observed from the Z direction. FIG.
(A) shows the configuration of the light shielding plate 7 itself in FIG. 1, having a light shielding portion 7A at the center, a ring-shaped light transmitting portion 7B around the light shielding portion 7A, and a light shielding portion 7C therearound.
Having. A light shielding plate having a shape as shown in FIG. 9A is used when the sample to be inspected is a mirror-finished sample. FIG. 9 (B)-
FIG. 9D shows a modification of FIG. 9A. In the light shielding plate of FIG. 9B, the shape of the light shielding portion 7A is linear. In the light-shielding plate of FIG. 9C, the shape of the light-shielding portion 7A is cross-shaped. The light-shielding plate in FIG. 9D includes a plurality of light-shielding portions 7A in which light-shielding portions 7A are arranged in a straight line. Note that in the case of FIG. 9D, the light-shielding portions may be arranged in a cross as in FIG. 9C. The light shielding plate having a shape as shown in FIGS. 9B to 9D is used when the sample to be inspected is a sample with a regular and directional pattern. Further, it goes without saying that the formation of the light shielding portion may be configured according to an existing pattern other than the shape shown in FIG.

It goes without saying that the light shielding portion 7A and the light transmitting portion 7B may be interchanged. In this case, the one-dimensional array detector 8 directly detects light. next,
A specific example in the case where the light shielding part and the light transmitting part are exchanged will be described. When the light-shielding portion 7A and the light-transmitting portion 7B are interchanged, a defect inspection device as shown in FIG. 10 is configured. That is, the defect inspection apparatus shown in FIG. 10 has a direct light detector 24 instead of the scattered light deflection light detector 28 shown in FIG. 2, and further has a black defect memory 27 instead of the scratch / foreign matter defect memory 2B. Become. The direct photodetector 24 detects an image formed by light transmitted or reflected normally by the sample to be inspected, and outputs a detection signal V2 to the A / D converter 25. The A / D converter 25 converts the detection signal V2 into a digital signal and outputs the digital signal to the determination circuit 26. The determination circuit 26 determines whether the detection signal V2 is smaller than a predetermined value,
A signal indicating the determination result is output to the black defect memory 27. The black defect memory 27 stores a signal indicating a determination result of the determination circuit 26 using the coordinate signals X and Y from the XY axis encoder 22 as addresses. When a repetitive pattern or a directional pattern is formed on the sample 5 to be inspected, the influence of the pattern is determined by using a difference image circuit corresponding to the adjacent pattern comparison processing method in the determination circuit 26. The minute pattern defect may be detected by removing it. The black defect memory 27 is the XY axis encoder 22
Circuit 26 using the coordinate signals X and Y from
Is stored. When the processing for the predetermined coordinate signal Y is completed, this coordinate signal is incremented, and the same processing is repeatedly executed to obtain defect information corresponding to the entire surface of the sample 5 to be inspected in FIGS. 11A and 11B. ing. The microprocessor unit (MPU) 2C determines a black defect of the sample to be inspected based on a signal from the black defect memory 27, converts the black defect into displayable data, and outputs the data to the display 2D. The display 2D is a display panel that visually displays display data from the MPU 2C.

FIGS. 11A and 11B are diagrams showing the configuration of each optical system for the sample 5 to be inspected held by the sample transport section 21 in FIG. 10, and the basic configuration corresponds to FIGS. 1A and 1B. I have. FIG. 11A is a diagram of the optical system viewed from the + Y-axis direction, and FIG. 11B is a diagram of the optical system viewed from the + X-axis direction. 1A and 1B in FIGS. 11A and 11B.
Components having the same configuration as those described above are denoted by the same reference numerals, and description thereof will be omitted. 11A and 11B are different from those shown in FIGS. 1A and 1B in that the light shielding plate 73 allows only light that is not scattered or deflected on the surface of the sample 5 to be inspected, that is, only direct light to pass. It is a point that has become. That is, the light-shielding portion 7A of the light-shielding plate 7 in FIG. 9A is a light-transmitting portion, and the light-transmitting portion 7B is a light-shielding portion or a light-shielding portion. As a result, only light (direct light) that has not been scattered or deflected on the surface of the sample 5 to be inspected transmits through the light transmitting portion of the light shielding plate 73 and forms an image on the surface of the one-dimensional array detector 8. Become. This gives 1
The dimensional array type detector 8 operates as the direct photodetector 28 in FIG. Conversely, the light scattered or deflected on the surface of the sample 5 to be inspected is blocked by the light blocking portion of the light blocking plate 73, and no image is formed on the surface of the one-dimensional array type detector 8.

FIG. 12 is a view schematically showing an output waveform V2 of the defect inspection apparatus using the optical system as shown in FIGS. 11A and 11B, that is, the direct photodetector 24 of FIG. Convex part 9
In 1, the output waveform V2 of the direct photodetector 24 decreases according to the shape of the convex portion 91. Scratched part 92, foreign matter adhesion part 93
Similarly, the output waveform V2 of the direct photodetector 24 in the concave and convex portions 94 is small but small in accordance with the defect shape.
On the other hand, when there is a defect on the sample to be inspected such as the black portion 95 which is in the form of a thin film and whose transmittance or reflectivity is different from normal, scattered light or polarized light is not generated at that portion. The output waveform V2 of the direct photodetector 24 is
Corresponding to the shape. Therefore,
Based on the greatly reduced output waveform V2, it is possible to easily recognize a black defect occurring on the test sample. 11A and 11B, FIG. 1A and FIG.
Although only the case where the light shielding plate is located behind the detection lens group as in B is illustrated, the invention is not limited to this, and the light shielding plate may be located inside the detection lens group as shown in FIGS. 5A and 5B. Needless to say, it may be located on the front side of the detection lens group as shown in FIGS. 6A and 6B.

FIG. 13 is a view showing an example of the configuration of a defect inspection apparatus using the two-dimensional array type detector 8A for scattered light deflection light as shown in FIGS. 3A and 3B. In this defect inspection apparatus, the output of the two-dimensional array type detector 8A is displayed on the corresponding scratch / foreign matter display monitor 111. FIG.
Reference numeral 4 denotes a screen 1 for scattered light polarized light at each position instead of using the one-dimensional array type detector 8 of FIGS. 1A and 1B or the two-dimensional array type detector 8A of FIGS. 3A and 3B.
FIG. 3 is a diagram illustrating a configuration example of a defect inspection device when the device 21 is arranged. FIG. 15 shows a two-dimensional array detector 8 for direct light instead of the one-dimensional array detector 8 shown in FIGS. 11A and 11B.
FIG. 2 is a diagram illustrating a configuration example of a defect inspection apparatus using A. In this defect inspection apparatus, the output of the two-dimensional array type detector 9 is displayed on the corresponding black defect display monitor 112. FIG. 16 shows the one-dimensional array detector 8 shown in FIGS. 11A and 11B and the two-dimensional array detector 8 shown in FIG.
FIG. 9 is a diagram illustrating a configuration example of a defect inspection apparatus in a case where a light screen 122 is directly arranged at each of these positions instead of using A. The defect inspection apparatus as shown in FIG. 13 to FIG. 16 can easily recognize the defect of the sample 5 to be inspected visually without performing complicated signal processing on the output from the detector.

In the above-described embodiment, the light beam from the multi-wavelength light source 1 is reflected by the concave mirror 4 using the half mirror 4B.
Although the case where the light flux reflected by the C and reflected by the concave reflecting mirror 4C passes through the half mirror and is condensed on the specimen 5 to be inspected has been described, the invention is not limited to this, and as shown in FIG. The light beam from the multi-wavelength light source 1 is directly reflected by the concave reflecting mirror 4E without using a half mirror between the inspection sample and the half mirror.
It goes without saying that the light may be focused on the sample 5 to be inspected. The intersection angle θa between the optical axis connecting the illumination stop 33 and the concave reflecting mirror 4E and the optical axis connecting the sample 5 to be inspected and the concave reflecting mirror 4E is desirably 45 degrees or less. FIG. 17 shows a case where the present invention is applied to the illumination means of the defect inspection apparatus shown in FIGS. 5A and 5B.
It goes without saying that the present invention may be applied to the illumination means of the defect inspection apparatus shown in FIGS. 4A and 4B, 6A and 6B, 11A and 11B.

In the above-described embodiment, a case has been described in which a light shielding member for shielding light is used for the light shielding plate 7. However, the present invention is not limited to this. You can use something that reflects the rest,
Alternatively, a half mirror whose reflectance is gradually changed may be used. That is, in the above embodiment,
Although the case of the binary level of light shielding and transmission has been described, it goes without saying that shading may be provided such as semi-transmission. For example, in the case of FIG. 9C, the light blocking ratio in the central portion is high, and the light blocking ratio is reduced toward the periphery.
In the case of (D), the light blocking ratio of the central circular portion may be increased, and the light blocking ratio of the peripheral circular portion may be reduced. Further, in the above-described embodiment, a case has been described in which a light shielding member for shielding light is used as the light shielding plate 7, but a phase plate, a polarizing plate (analyzer), or the like may be used instead of the light shielding member. In the case of using a phase plate, it is necessary to provide an illumination ring diaphragm between the sample 5 to be inspected and the slit diaphragm 3 as described in a column of “Phase contrast microscope” in a textbook or the like. Description is omitted. When a polarizing plate is used,
The details of obtaining a polarized illumination by installing a polarizer in the illumination system are also described in detail in the column of “Polarizing microscope” in a textbook or the like, and thus the description is omitted here. Also, needless to say, when a phase plate or a polarizing plate is used, shading such as semi-transmission may be similarly applied. When a phase plate is used, the detection signal V1 of the direct light detector 24 and the detection signal V2 of the scattered light deflected light detector 28 shown in FIG. 2 are different from the detection signal V2 having a phase difference and the detection signal V2 having no phase difference, respectively. It goes without saying that the detection signal V1 becomes the detection signal V2 having a change in polarization and the detection signal V1 having no change in polarization when a polarizing plate is used. By using a phase plate and a polarizing plate in this way,
These defects can also be inspected for a phase shift photomask, an optical glass substrate, a phase shift photomask substrate, a Si wafer with a thin film, an LCD alignment film, and the like.
For example, a 550 × 650 mm LCD polarizing plate, retardation plate, glass substrate, color filter, or 300φ LSI
2. Si wafer for LSI, 5 inch diagonal LSI photomask, 40 inch diagonal PDP glass substrate, electrode substrate,
5 inch diameter polycarbonate substrate for DVD
It is possible to collectively inspect the entire surface of the sample 5 having no large-area panne such as a polycarbonate substrate for an Mo (magneto-optical) disk having an inch diameter and having a pattern. When there is no thin film or color filter on the surface of the sample 5, it is not necessary to use the multi-wavelength light source 1 having a wide wavelength distribution. A multi-wavelength light source 1 having a narrow wavelength distribution such as an e-ray spectrum of a high-pressure mercury lamp can also be used.

[0040]

According to the present invention, a wide-field image can be formed using a small-diameter imaging lens, and the cost of the entire defect inspection apparatus can be reduced.

[Brief description of the drawings]

FIG. 1A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a first embodiment as viewed from an X-axis direction.

FIG. 1B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the first embodiment as viewed from the Y-axis direction.

FIG. 1C is a diagram showing a conceptual diagram in a case where the concave reflecting mirror in FIGS. 1A and 1B is replaced with a convex lens.

FIG. 2 is a diagram showing a schematic configuration of an entire defect inspection apparatus that detects defects and foreign matter on a color filter substrate and a pixel electrode substrate of a liquid crystal display by scattered light or polarized light transmitted or reflected on the surface of a sample to be inspected.

FIG. 3A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a second embodiment as viewed from the X-axis direction.

FIG. 3B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the second embodiment as viewed from the Y-axis direction.

FIG. 4A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a third embodiment as viewed from the X-axis direction.

FIG. 4B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the third embodiment as viewed from the Y-axis direction.

FIG. 4C is a diagram showing a conceptual diagram when the concave reflecting mirror in FIGS. 4A and 4B is replaced with a convex lens.

FIG. 5A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a fourth embodiment as viewed from the X-axis direction.

FIG. 5B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the fourth embodiment as viewed from the Y-axis direction.

FIG. 6A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a fifth embodiment as viewed from the X-axis direction.

FIG. 6B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the fifth embodiment viewed from the Y-axis direction.

FIG. 7 is a diagram schematically showing an output waveform of the scattered light deflection light detector of FIG. 2 in a surface state of a sample to be inspected.

FIG. 8 is a view showing two methods of a defect detection method according to the defect inspection apparatus according to the present invention.

FIG. 9 is a view showing a modification of the light shielding plate.

FIG. 10 is a diagram showing a schematic configuration of an entire defect inspection apparatus that detects defects and foreign substances on a color filter substrate and a pixel electrode substrate of a liquid crystal display by direct light transmitted or reflected on the surface of a sample to be inspected.

FIG. 11A is a diagram showing a schematic configuration of each optical system of a defect inspection apparatus according to a sixth embodiment as viewed from the X-axis direction.

FIG. 11B is a diagram showing a schematic configuration of each optical system of the defect inspection apparatus according to the sixth embodiment as viewed from the Y-axis direction.

12 is a diagram schematically showing an output waveform of the direct photodetector in FIG. 10 in a surface state of a sample to be inspected.

FIG. 13 is a diagram showing another configuration example of the defect inspection apparatus of FIG. 2;

FIG. 14 is a diagram showing still another configuration example of the defect inspection apparatus of FIG. 2;

FIG. 15 is a diagram showing another example of the configuration of the defect inspection apparatus of FIG. 10;

FIG. 16 is a diagram showing still another example of the configuration of the defect inspection apparatus of FIG. 10;

FIG. 17 is a view showing a modification of the illumination means of the defect inspection apparatus according to the embodiment of the present invention.

[Explanation of symbols]

1 ... light source, 2 ... condenser lens, 3,3B ... slit aperture,
S, SB: slit, 3A: square aperture slit stop, S
A: square aperture slit, 33: illumination stop, 4A: auxiliary condenser lens, 4B: half mirror, 4C, 4D: concave reflecting mirror, 5: transmission material type inspection sample, 5A: reflection material type inspection sample, 6 , 6A, 6B, 6C ... detection lens group, 7, 7
1, 72, 73: light shielding plate, 70: light condensing position, 7A: light shielding portion, 7B: light transmitting portion, 7C: light shielding portion, 8: one-dimensional array type detector, 8A: two-dimensional array type detector, 21 sample transporting unit, 22 XY axis encoder, 23 detector driving circuit, 24 direct light detector, 25, 29 A / D converter, 26, 2A determination circuit, 27 black defect memory, 2
8 scattered light deflection light detector, 2B scratch / foreign matter defect memory, 2C MPU, 2D display, 81 lighting means, 8
2 ... Imaging means, 111 ... Scratch / foreign matter display monitor, 112
... Monitor for displaying black defects, 121 ... Screen for scattering / deflecting light, 122, Screen for direct light

Claims (12)

[Claims] An illumination unit for irradiating illumination light from a light source to a sample to be inspected by using a concave reflecting mirror, and a transmitted or reflected light of the illumination light applied to the sample to be inspected using an imaging lens. Imaging means for detecting an image with a one-dimensional array detector; signal processing means for processing a signal output from the detector to detect a defect on the sample to be inspected; A defect transport device for transporting the sample to be inspected in a predetermined direction, wherein the illumination light of the illumination unit is formed by a light beam converging at each point on the sample to be inspected. The concave reflecting mirror is configured such that a light beam angle which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected is smaller than an opening angle of the imaging lens. And the illumination light is on the sample to be inspected. The light source is configured to irradiate an area including a linear area, and each of the luminous fluxes of the illumination light is focused without aberration near a pupil of the imaging lens. A transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the lens, and a light-shielding unit that shields a part of transmitted light or reflected light of the illumination light in the linear region on the sample to be inspected. Detecting the image of the linear region formed by the light passing through the transmitting portion with the one-dimensional array detector, and the signal processing means is configured to detect the image based on a detection signal from the one-dimensional array detector. Detecting a defect of the sample to be inspected, wherein the sample transporting means continuously transports the sample to be inspected in a direction perpendicular to a longitudinal direction of a linear region irradiated by the illumination light. Defect inspection equipment. 2. Illumination means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and transmitting or reflecting the illumination light illuminated on the sample to be inspected using an imaging lens. Imaging means for forming an image with a one-dimensional array detector, and processing a signal output from the one-dimensional array detector so that a defect on the sample to be inspected can be visually recognized. A defect inspection apparatus for a sample to be inspected, comprising a display unit for displaying, and a sample transporting unit for transporting the sample to be inspected in a predetermined direction, wherein the illumination light of the illumination unit is provided on each of the inspection samples. The concave reflecting mirror is configured such that a light beam angle, which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected, is larger than an aperture angle of the imaging lens. The illumination is also configured to be smaller. Are configured to irradiate a region including a linear region on the sample to be inspected, and each of the luminous fluxes of the illumination light is condensed near the pupil of the imaging lens without aberration. The image unit is a transmission unit having a size equal to or smaller than an exit pupil installed near the pupil of the imaging lens, and a part of the transmitted light or reflected light of the illumination light in the linear region on the test sample. A light-shielding portion that shields light, wherein the one-dimensional array-type detector detects an image of a linear region formed by light passing through the transmissive portion, and the display means detects the image from the one-dimensional array-type detector. Based on the detection signal, the defect of the sample to be inspected is displayed so as to be distinguishable, and the sample transporting unit moves the sample to be inspected in a direction perpendicular to the longitudinal direction of the linear region irradiated by the illumination light. Defect inspection equipment characterized by continuous transport Place. 3. Illumination means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and forming an image of transmitted light or reflected light of the illumination light illuminated on the inspection sample by the illumination means. Imaging means for forming an image with a lens and detecting the image with a two-dimensional array type detector, and processing a signal output from the two-dimensional array type detector to detect a defect on the sample to be inspected A defect inspection apparatus for a sample to be inspected, comprising: a signal processing unit; and the illumination light of the illumination unit is composed of a light beam converging at each point on the sample to be inspected. The luminous flux angle, which is the maximum cone angle of the luminous flux of the illumination light incident or emitted at each point on the inspection sample, is configured to be smaller than the opening angle of the imaging lens, and the illumination light is the inspection sample. To illuminate the upper planar area. Each of the luminous fluxes of the illumination light is configured to converge without aberration near the pupil of the imaging lens, and the imaging unit includes an exit pupil or less located near the pupil of the imaging lens. And a light-shielding portion that shields a part of the transmitted light or the reflected light of the illumination light in the planar region on the sample to be inspected, and forms an image by the light that has passed through the transparent portion. The two-dimensional array type detector detects an image of the planar area to be processed, and the signal processing unit detects a defect of the sample to be inspected based on a detection signal from the two-dimensional array type detector. Characteristic defect inspection equipment. 4. An illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and forming an image of transmitted light or reflected light of the illumination light illuminated on the inspection sample by the illumination means. A defect inspection apparatus that forms an image with a lens and displays the image on a screen, wherein the illumination light of the illumination unit is formed of a light beam converging at each point on the sample to be inspected, and the concave reflecting mirror is A light beam angle, which is a maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than an opening angle of the imaging lens; The illumination device is configured to irradiate a planar region on an inspection sample, and each of the light beams of the illumination light is focused near the pupil of the imaging lens without aberration. The projection lens set near the pupil of the image lens A light-transmitting portion having a size equal to or smaller than the pupil, and a light-shielding portion that shields a part of transmitted light or reflected light of the illumination light in the planar region on the test sample, and light that has passed through the transparent portion. A defect of the sample to be inspected based on the image on the screen, the defect being inspected. 5. An illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and forming an image of transmitted light or reflected light of illumination light illuminated on the inspection sample by the illumination means. Imaging means for forming an image with a lens and detecting the image with a two-dimensional array type detector, and processing a signal output from the two-dimensional array type detector to visually recognize a defect on the sample to be inspected. A defect inspection apparatus for a specimen to be inspected, comprising: a display means for displaying the inspection light on the inspection specimen, wherein the illumination light of the illumination means is composed of a light flux converging at each point on the specimen to be inspected; A light beam angle, which is a maximum cone angle of the light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than an opening angle of the imaging lens; Irradiates a planar area on the test sample Each of the light beams of the illumination light is configured to converge without aberration near the pupil of the imaging lens, and the imaging unit includes an exit pupil installed near the pupil of the imaging lens. A light-transmitting part having the following size; and a light-shielding part that shields a part of transmitted light or reflected light of the illumination light in the planar region on the sample to be inspected. The two-dimensional array type detector detects an image of the planar region to be imaged, and the display means displays a defect of the sample to be inspected based on a detection signal from the two-dimensional array type detector. And a defect inspection apparatus. 6. An illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and transmitting or reflecting the illumination light illuminating the sample to be inspected using an imaging lens. Imaging means for detecting an image with a one-dimensional array detector; signal processing means for processing a signal output from the detector to detect a defect on the sample to be inspected; A defect transport device for transporting the sample to be inspected in a predetermined direction, wherein the illumination light of the illumination unit is formed by a light beam converging at each point on the sample to be inspected. The concave reflecting mirror is configured such that a light beam angle which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected is smaller than an opening angle of the imaging lens. And the illumination light is on the sample to be inspected. It is configured to irradiate a region including a linear region longer than the aperture of the imaging lens, and each of the light beams of the illumination light is condensed near the pupil of the imaging lens without aberration. The imaging means includes: a transmission portion having a size equal to or smaller than an exit pupil provided near a pupil of the imaging lens; and a transmission light or a reflection light of the illumination light in the linear region on the test sample. A light-shielding portion that shields the light-transmitting portion, wherein an image of a linear region formed by light passing through the transmission portion is detected by the one-dimensional array-type detector; Detecting a defect of the inspection sample based on a detection signal from a detector, wherein the sample transporting unit continuously connects the inspection sample in a direction perpendicular to a longitudinal direction of a linear region irradiated by the illumination light. The image is transferred to the A defect inspection apparatus for inspecting various defects on the sample to be inspected in a region wider than the diameter of the lens. 7. An illuminating means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and transmitting or reflecting the illumination light illuminating the sample to be inspected using an imaging lens. Imaging means for detecting the image with a one-dimensional array detector, and processing means for processing a signal output from the detector to visually display a defect on the sample to be inspected. A defect transport device for transporting the sample to be inspected in a predetermined direction, wherein the illumination light of the illumination means converges at each point on the sample to be inspected. The concave reflecting mirror is configured such that a light beam angle, which is a maximum cone angle of a light beam of the illumination light incident or emitted at each point on the sample to be inspected, is smaller than an opening angle of the imaging lens. Wherein the illumination light is It is configured to irradiate an area including a linear area longer than the aperture of the imaging lens on the specimen, and each of the light beams of the illumination light is condensed near the pupil of the imaging lens without aberration. Wherein the imaging means comprises: a transmitting portion having a size equal to or smaller than an exit pupil provided near a pupil of the imaging lens; and a transmitted light or a reflected light of the illumination light in the linear region on the sample to be inspected. A light-blocking portion that blocks a part of the light, wherein the one-dimensional array-type detector detects an image of a linear region formed by the light that has passed through the transmitting portion, Based on the signal from the array type detector, the defect of the sample to be inspected is displayed so as to be distinguishable, and the sample transporting means is arranged in the direction perpendicular to the longitudinal direction of the linear region irradiated by the illumination light. By continuously transporting the test sample, A defect inspection apparatus for inspecting various defects on the sample to be inspected over an area wider than the diameter of the imaging lens. 8. An illumination means for irradiating illumination light from a light source to a sample to be inspected by using a concave reflecting mirror, and transmitting or reflecting the illumination light illuminating the sample to be inspected using an imaging lens. Imaging means for detecting the image with a two-dimensional array detector, and signal processing means for processing a signal output from the detector to detect a defect on the sample to be inspected. A defect inspection apparatus for a specimen to be inspected, wherein the illumination light of the illuminating means is composed of a light beam converging at each point on the specimen to be inspected, and the concave reflecting mirror is provided on the specimen to be inspected. The light beam angle, which is the maximum cone angle of the light beam of the illumination light incident or emitted at each point, is configured to be smaller than the opening angle of the imaging lens, and the illumination light forms the image on the inspection sample. It illuminates a planar area larger than the lens aperture Each of the light beams of the illumination light is configured to converge without aberration near the pupil of the imaging lens, and the imaging unit includes an exit pupil installed near the pupil of the imaging lens. A light-transmitting part having the following size; and a light-shielding part that shields a part of transmitted light or reflected light of the illumination light in the planar region on the sample to be inspected. The two-dimensional array type detector detects an image of the planar area to be formed, and the signal processing unit is configured to detect an area larger than the aperture of the imaging lens based on a detection signal from the two-dimensional array type detector. A defect inspection device for detecting a defect on the sample to be inspected. 9. Illumination means for irradiating illumination light from a light source to a sample to be inspected using a concave reflecting mirror, and forming an image of transmitted light or reflected light of the illumination light illuminated on the sample to be inspected by an imaging lens. And a defect inspection apparatus for displaying the image on a two-dimensional screen, wherein the illumination light of the illumination means is composed of a light beam converging at each point on the sample to be inspected, and the concave reflecting mirror is The luminous flux angle, which is the maximum cone angle of the luminous flux of the illumination light incident or emitted at each point on the inspection sample, is configured to be smaller than the opening angle of the imaging lens, and the illumination light is the inspection sample. It is configured to irradiate a planar area larger than the aperture of the imaging lens above, and each of the luminous fluxes of the illumination light is focused near the pupil of the imaging lens without aberration. The imaging means is provided near the pupil of the imaging lens. A transmission portion having a size equal to or smaller than an exit pupil installed beside the light source; and a light-shielding portion that shields a part of transmitted light or reflected light of the illumination light in the planar region on the sample to be inspected. Defect inspection, wherein an image of a planar area formed by light passing through the portion is formed on the screen, and the defect of the sample to be inspected is made visible based on the image on the screen. apparatus. 10. An illumination means for irradiating illumination light from a light source to a sample to be inspected by using a concave reflecting mirror, and forming an image of transmitted light or reflected light of the illumination light applied to the sample to be inspected by an imaging lens. And an image forming means for detecting the image with a two-dimensional array detector, and a display means for processing a signal output from the detector to visually display a defect on the sample to be inspected. A defect inspection apparatus for a sample to be inspected, wherein the illuminating light of the illuminating means is composed of a light beam converging at each point on the sample to be inspected, and the concave reflecting mirror includes The light beam angle, which is the maximum cone angle of the light beam of the illumination light incident or emitted at a point, is configured to be smaller than the opening angle of the imaging lens, and the illumination light is the imaging lens on the sample to be inspected. Irradiate a planar area larger than the aperture of Wherein each of the luminous fluxes of the illumination light is condensed in the vicinity of the pupil of the imaging lens without aberration, and the imaging means includes an exit pupil provided in the vicinity of the pupil of the imaging lens. A light-transmitting part having the following size; and a light-shielding part that shields a part of transmitted light or reflected light of the illumination light in the planar region on the sample to be inspected. The two-dimensional array type detector detects an image of the planar area to be formed, and the display means detects an image in a region wider than the aperture of the imaging lens based on a detection signal from the two-dimensional array type detector. A defect inspection apparatus for displaying a defect of the sample to be inspected in a distinguishable manner. 11. The light-shielding portion blocks light transmitted or reflected normally through the test sample among light transmitted or reflected by the test sample, and the transmission portion forms a defect on the surface of the test sample. The defect inspection apparatus according to any one of claims 1 to 10, wherein scattered light or deflected light caused by (1) is guided to the one-dimensional array type detector or the two-dimensional array type detector. . 12. The light-shielding portion shields scattered light or deflected light resulting from a defect on the surface of the sample to be inspected among transmitted light or reflected light of the sample to be inspected, and the transmission portion normalizes the sample to be inspected. The defect inspection apparatus according to any one of claims 1 to 10, wherein the light transmitted to or reflected from the device is guided to the one-dimensional array type detector or the two-dimensional array type detector. .