JPH05223521A - Macro inspection apparatus capable of reading out position - Google Patents

Abstract

PURPOSE:To accurately read out the position of a defect when the defect of a specimen is detected by means of a macro inspection machine. CONSTITUTION:A macro inspection apparatus is composed of the following: an inspection-light projection unit 1 with which a specimen is irradiated; a tilted specimen stand 2 which is arranged at the rear of the specimen S and which can be tilted freely; a spot projection unit 4 which is attached integrally to the tilted specimen stand 2; and an X-Y stage 3 which is equipped with a length-measuring instrument. The X-Y stage 3 is moved to the X-Y axis direction; the spot projection unit 4 is made to coincide with a defect part in the specimen; the movement amount of the stage is measured automatically; the defect part is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a macro inspection device capable of reading a defect position on a surface of an LCD substrate or the like.

[0002]

2. Description of the Related Art Conventionally, when a transparent substrate such as a quartz wafer or LCD is irradiated with light to detect scratches and film thickness unevenness on the sample surface with a macro inspection device with the naked eye, the sample is used as a product. It is necessary to analyze the defect again by enlarging the defective portion again with another inspection machine such as a microscope to determine whether the defect is possible or how much the quality and function are deteriorated. In this case, the operator should remember the defect position found in the first inspection, or if it is a transparent sample such as an LCD substrate, mark it on the back surface of the substrate and then move on to the next inspection. The defect part was analyzed. However, in order to bring the defective part of the sample placed on the microscope stage directly under the objective, the sample had to be moved back and forth, left and right, and the revolver and the like inevitably hindered, bringing the defect position directly below. It was difficult and annoying to the worker.

Further, if the sample is large like an LCD substrate,
In some cases, there are several defective parts in the same sample, the operator cannot remember these defective positions, and much time is required for marking. This marking operation itself was not good in terms of contamination.

FIG. 6 shows a schematic mechanism of a conventional IC macro device. The light from the light source A is projected onto the sample S via the lens B to inspect a defect of the sample S on the sample table D which can be swung and rotated. The device for reading the coordinates of the defect position is It could not be mounted on the sample table D which swings due to the mechanism and obstacles. Therefore, the entire sample S mounted on the sample table D is copied on a TV monitor (not shown), and first, the defective portion on the sample surface is inserted with an indicator stick or the like, and the position where the image is reflected on the monitor is roughly estimated. There was something to read. In this case, there is a problem that the TV monitor occupies a large space, and there is a complexity that an operator needs to see the sample itself and the TV monitor at the same time, and the accuracy is naturally poor.

Even so, as shown in FIG. 7, the IC wafer E
In the case of the inspection, since the pattern to be the chip C is printed at intervals, it is easy for the operator to remember the defect position, such as "in what column from the left, in what upper right of the chip from the left". Even with such a memory method, I managed to make it. However, in the case of an LCD substrate, it is extremely difficult to specify the position because the entire screen with a diagonal of 10 inches or more is filled with the same fine pattern.

As described above, the LCD substrate has many defective portions, there is no mark for memorizing the defective portions, and the number of processings per unit time, that is, the through butt is required to be several times larger than that of the IC. Therefore, there is a need for an apparatus for inspecting the defect coordinates after reading the defect coordinates with another apparatus and moving the sample by instructing the coordinates to call the defect portion.

[0007]

As described above, the operator must remember the defect position, mark it on the back surface of the LCD substrate, or monitor it on the TV and set the tip of the indicator rod pointing to the sample defect part. There is a complicated and inconvenient work such as reading on the monitor, and if there are many defective parts, the problem becomes more and more difficult, the defect position can not be remembered, or the mark is a problem of contamination and man-hours. However, there are drawbacks such as poor accuracy.

As described above, the present invention aims to be able to inspect defect positions of an LCD substrate or the like efficiently and accurately,
Furthermore, it realizes the automation.

[0009]

[Means for Solving the Problems] A tiltable sample holder that holds a sample and a stage that is provided at the bottom of the sample sample and that can move in the X and Y axis directions facing the sample.
The stage consists of a reader that reads the amount of movement in each of the X and Y axis directions, and a spot projection unit that is integrally attached to the stage and illuminates the sample surface.
It is characterized in that the amount of movement of the stage is displayed as a coordinate position of the defective portion by moving the stage in the axial direction to match the spot with the defective portion of the sample.

[0010]

Since the present invention has the above-mentioned structure, when a defect of the sample is found, the position coordinates of the defective portion of the stage can be accurately and efficiently read by a simple operation of matching the spot projection unit to the position. It became so. Moreover, automation has become possible.

[0011]

1 and 2 are basic conceptual diagrams of the present invention. 1
Is an inspection light projecting unit including a light source 1a and a lens 1b for irradiating the sample S from above, and the tilted sample base 2 holding the sample S is tilted only in one direction. The stage 3 has a table 3 that moves in each of the x and y axes.
It is provided with a and 3b and readers 3x and 3y for reading the movement amounts thereof, respectively. Reference numeral 4 denotes a spot light projecting unit including a lens 4a and an LED light source 4b, which is attached to the stage 3 and is configured so that spot light is applied from below the sample S.

In the figure, an observer irradiates the sample S with inspection light to search for a defective portion, and if found, moves the stage 3 to align the spot projection unit 4 with the defective portion. Read the coordinates of the x and y axes at that time. Since the origin P of the lower right corner of the transparent glass of the sample S is aligned with the coordinate center of the X and Y axes, the defect coordinates from the origin P can be read. In this case, the reading accuracy may be about ± 0.5 mm. The reason for this is that in the case of inspecting with a microscope, the diameter is about 4 mm in the case of an eyepiece with 20 times the field of view of a 5 × objective, so it is sufficient if a defect can be inserted in this field of view. Therefore ±
It may be 1 mm, but preferably ± 0.5 mm. This is because the first defect may be searched for when using a 10x objective. Therefore, it is preferable to select the spot projection unit 4 capable of irradiating the sample with the spot light having a diameter of about 1 mm.

FIG. 3 shows a specific embodiment of the present invention. The light emitted from the inspection light projecting unit 1, that is, the light from the light source 1a having a parabolic reflection surface, is condensed once and then converted into a large light beam.
The Fresnel lens 1b, which is a sheet, converts the light into parallel light or convergent light onto the sample S held on the tilted sample table 2 with the inspection light. On this tilted sample table 2, a sample holder 2a for holding a sample S, and a motor for tilting the tilted sample table 2 up and down.
2b is provided, and the tilted sample table 2 is tilted 0 ° to 45 ° facing the observer side with the spindle 2c as a fulcrum by the drive of the motor 2b, as described later. At the time of attaching and detaching the sample S, the sample S is lowered so that its tip is lowered onto the stopper 2d and stopped.
In addition, a stage 3 that is movable in the x and y axis directions is provided at the bottom of the tilted sample table 2, and reading is performed to read the amount of movement of each of the tables 3a and 3b of the stage 3 that moves in the x and y axis directions. 3x and 3y are provided. Further, above the coordinate plane of the stage 3, spot projection units 4 are fixedly mounted on the stage 3 in several columns and several rows.
It moves together with the movement in the axial direction.

FIG. 4 shows an example of installation of a plurality of spot projection units 4. In the figure, the x and y axis directions are m,
It is divided into n equal parts and one spot projection unit 4 (6 in this case, 4A ₁ , 4A ₂ , 4A ₃ , 4B ₁ , 4, 4B ₂ , 4B _{3 for} each range unit).
Indicates the inspection range (A ₁ , A ₂ , A ₃ , B ₁ , B
₂ , B ₃ ). That is, m = 3n
= 2, so the inspectable range in the x and y directions is K
X, KY, strokes of the stage 3 in the x and y directions are kx,
If ky, kx = KX (1 / m), that is, kx = KX (1/3), and ky = KY (1 / n), that is, ky = KY (1/2). 5 is a controller, 6 is a computer, and 6a is a coordinate display. The robot unit 7 includes an elevator base 7a having a function of moving up and down, a rotary plate 7b rotatably provided on the base 7a, and a sample transfer arm that horizontally slides back and forth on the rotary plate 7b. It consists of 7c. These are in contact with each other so as to be movable according to an instruction from the controller 5. The sample storage cassette 8 includes a base 8a,
It is composed of a plurality of sample storage shelves 8b provided on the base 8a.

FIG. 5 shows a control communication system between the controller 5 and each device member. First, operate the controller 5,
The elevator table 7a is moved up and down to an appropriate height, the rotary plate 7b of the robot unit 7 is rotated, and the sample transfer arm 7c is slid toward the position of the desired sample S stored in the sample storage cassette 8. The target sample S is moved forward, the sample transfer arm 7c is slid backward to rotate the turntable 7b, and the sample S is transferred to the sample holder 2a of the tilted sample table 2. When the sample holder 2a securely holds the sample S, the motor 2b is driven until the angle desired by the observer is reached, and the tilted sample table 2 is stopped. The above-described series of operations may be performed by manually operating the controller 5, or if all of them are stored in the computer 6 and only the place where the sample S is placed is designated by a key, naturally all the operations are performed. It can also be automated.

At this time, the light source 1a of the inspection projection unit 1 and the LED light source 4b of the spot projection unit 4 are turned on. When the observer finds a defective portion of the sample S, the spot projection unit (for example, 4A ₁ ) closest to the defective portion is selected from the six spot projection units 4 provided on the stage 3 of the tilted sample stage 2. , A push button of the controller 5 or a key (not shown) is operated to align with the defective portion. The amount of movement of the spot projection unit 4A ₁ on the coordinates of the stage 3 can be read by the readers 3x and 3y, respectively, and is input to the computer 6 so that the defective portion is recorded as x and y coordinates. By repeating this operation, a plurality of defective portions can be read. After the inspection is completed, tilt the sample table 2 to the stop
After returning to the original position where it stops contacting 2d, the sample S is stored in the sample storage cassette 8 by the sample transfer arm 7c, and the next detailed inspection is carried out. Here, the sample S is transferred to and from the sample storage cassette 8, but it goes without saying that the sample S may be directly transferred to a microscope stage (not shown) and then stored in the sample storage cassette. In this case, if a stage having the same scale as that of the stage of the present invention is also provided on the side of the precision inspection machine in the next step, the defective portion can immediately appear, which is extremely effective.

[0017]

The position readable macro inspection apparatus according to the present invention can easily read the position coordinates of the defective portion on the sample substrate, and is free from the complexity of marking and storing. It greatly contributes to simplification and enhancement of work efficiency. Furthermore, even when re-inspecting precisely with another inspection machine, the coordinate position of the defective portion can immediately appear, so that a series of inspection operations can be automated.

[Brief description of drawings]

FIG. 1 is a side view showing the basic concept of the present invention.

FIG. 2 is a perspective view showing the basic concept of the present invention.

FIG. 3 is a side view of a configuration showing an embodiment of the present invention.

FIG. 4 shows an arrangement example of a spot projection unit according to the present invention.

FIG. 5 shows a control communication system between the controller according to the present invention and other device members.

FIG. 6 is a schematic mechanism diagram of a conventional macro inspection device.

FIG. 7 shows an example of an IC wafer chip arrangement.

[Explanation of symbols]

 1 Inspection / projection unit 2 Inclined sample stage 3 Stage 3x, 3y Reader 4, 4a Spot projection unit 5 Controller 6 Computer 6a Display 7 Robot unit 8 Sample storage cassette S Sample

Claims (2)

[Claims] 1. A macro inspection apparatus for irradiating a transparent sample substrate such as a quartz wafer or LCD with light to detect scratches, dust, film thickness unevenness, etc. on the sample surface with the naked eye, and is capable of pivoting to hold the sample. An inclined sample stage, a stage provided at the bottom of the inclined sample stage and movable in the X and Y axis directions facing the sample, and a reader for reading the movement amount of each of the X and Y axis directions of the stage, It consists of a spot projection unit that is integrally attached to the stage and illuminates the sample surface.By moving the stage in the X and Y axis directions to match the spot to the defective portion of the sample, the movement amount of the stage A position readable macro inspection device characterized by displaying as a coordinate position of a part. 2. The spot projection unit is installed for each unit range in which the stage is vertically and horizontally divided into a plurality of units, and the stroke of the stage is inversely proportional to the number of the spot projection units. A position readable macro inspection device according to item 1.