KR20150077596A - Substrate inspecting apparatus and inspecting method using the same - Google Patents

Abstract

In accordance with an embodiment of the present invention, a substrate inspecting apparatus comprises: a substrate transmission unit to transmit a substrate; a movement focusing unit moved from an upper part of the substrate transmission unit to an inspection position of the substrate to perform focusing for photographing an image; a movement unit to move the movement focusing unit; a fixing photographing unit fixed and disposed on one side of the substrate transmission unit to acquire an image for the inspection position placed on the movement unit in accordance with the result of the focusing performed in the movement unit; and a controller to control operations of the substrate transmission unit, the movement focusing unit, the movement unit and the fixing photographing unit. In accordance with the present invention, the substrate inspecting apparatus allows the distance between an inspecting coordinate and a laser beam generator to be constantly maintained by the movement focusing unit, by which the accuracy of laser beam focusing can be uniformly maintained, and also is capable of rapidly acquiring the inspection image and securing a multiple simultaneous focusing state for several inspecting coordinates using a plurality of movement focusing units.

Description

[0001] The present invention relates to a substrate inspecting apparatus and a substrate inspecting method using the substrate inspecting apparatus.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate inspection apparatus and a substrate inspection method using the same, and more particularly, to a substrate inspection apparatus for reviewing and reviewing a substrate that has been roughly inspected in advance and a substrate inspection method using the same.

Inspection of the substrate during the manufacture of the substrate for a thin film display is typically carried out. Substrate inspection is divided into initial inspection and review inspection. Initial inspection is the process of inspecting the whole substrate in a short time. And review inspections are performed more precisely for review inspections found in the initial inspections.

Review inspections are performed by enlarging the inspections at a high magnification. Since the test object is inspected at a high magnification, the focus of the test object must be precisely adjusted, and this focus adjustment should be performed automatically.

The operation of automatically focusing is called auto focusing. In a substrate inspection apparatus, a laser can be used for autofocusing. In the autofocusing using a laser, a laser beam is irradiated to an inspection target position on a substrate. When an image of the laser beam reflected from the substrate reaches the image sensor, pixel values (intensity of incident light, etc.) And determines whether the focus is matched. When it is determined that focus alignment is performed, the illumination light is operated to acquire an image of the inspection position through the image sensor.

Korea Open Patent No. 2012-0105149 (released on September 25, 2012)

An object of the present invention is to provide a method and an apparatus for acquiring a final inspection image through a stationary photographing unit having a fixed position and a method of performing autofocusing on the inspection image provided to the stationary photographing unit using a moving- And a substrate inspection method using the same.

A moving part for moving the moving focusing part, a moving part for moving the moving part, a moving part for moving the substrate, a moving part for moving the substrate from the one side of the transmitting part to the inspection position of the substrate, A stationary photographing unit that is fixed on one side of the transmitting unit and acquires an image of the inspection position according to a focusing result performed by the moving unit, and a controller that controls the operation of the substrate transferring unit, the moving focusing unit, And a control unit for controlling the control unit.

The moving focusing unit may include an objective lens near the substrate, a motor for controlling the focusing of the objective lens, a laser oscillating unit for irradiating the laser beam toward the substrate through the objective lens, An image sensor may be provided.

The moving focusing unit may include a beam splitter installed between the objective lens and the image sensor for focusing so as to provide an image of the substrate to the fixed image pickup unit and providing an optical axis separated to the fixed image pickup unit.

The moving focusing unit may include an optical system having a flare lamp and causing an optical axis of the flare lamp and an optical axis of the laser incident on the substrate to be coaxial with respect to an inspection position of the substrate.

The fixed photographing unit includes a reflection mirror for reflecting an image of the inspection position of the substrate provided from the moving image focusing sensor to the inspection image sensor, a zoom mirror provided between the reflection mirror and the inspection image sensor, Optical system.

Wherein the moving focusing unit includes a first moving focusing unit and a second moving focusing unit that are independently moved by the moving unit, and the reflecting mirror of the stationary photographing unit is configured to detect an image provided by the first moving focusing unit, And a beam splitter is provided between the reflection mirror and the zoom optical system for reflecting the image provided by the second moving focusing unit to the inspection image sensor.

A method for inspecting a substrate according to an exemplary embodiment of the present invention includes the steps of: receiving initial inspection information on an externally inspected substrate and setting inspection coordinates of a substrate necessary for a review inspection; The method comprising the steps of: selectively transferring the substrate and the moving focusing unit; performing focusing using a laser in the moving focusing unit with respect to the inspection coordinates of the substrate; operating the lamp when the focusing is completed, And an image is transmitted to a fixed photographing unit fixed at a predetermined position via the moving focusing unit to photograph an image.

Wherein a plurality of inspection coordinates of the substrate are set, each inspection coordinate of each of the substrates is individually matched to a plurality of the moving focusing parts, and each of the moving focusing parts is moved independently to focus the plurality of inspection coordinates Can be performed.

It is possible to prevent the time for acquiring an image from each of the moving focusing units from progressing at the same time so that images are simultaneously transmitted from the moving focusing units to the fixed photographing units.

The apparatus for inspecting a substrate and the method of inspecting a substrate using the apparatus according to the present invention can maintain the accuracy of laser focusing uniformly because the distance between the inspection coordinates and the laser oscillating unit is kept constant by the moving focusing unit, It is possible to perform simultaneous multiple inspection of a plurality of inspection coordinates and obtain a rapid inspection image.

1 is a block diagram showing the configuration of a substrate inspection apparatus according to an embodiment of the present invention.
2 is a perspective view of a substrate inspection apparatus according to an embodiment of the present invention.
3 is a view showing an optical system of a substrate inspection apparatus according to an embodiment of the present invention.
4A and 4B are views for explaining the operation of the substrate inspection apparatus according to the embodiment of the present invention.
5 is a view for explaining the operation of a substrate inspection apparatus according to another embodiment of the present invention.
6 is a view for explaining a substrate inspection method according to an embodiment of the present invention.

Hereinafter, embodiments of a substrate inspection apparatus and a substrate inspection method using the same according to the present invention will be described with reference to the drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, To be fully informed.

FIG. 1 is a block diagram showing a configuration of a substrate inspection apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view of a substrate inspection apparatus according to an embodiment of the present invention.

The substrate inspection apparatus 10 according to the embodiment of the present invention is a review substrate inspection apparatus for reviewing defects found on a substrate S having undergone initial inspection in another substrate inspection apparatus. The initial inspection, which is the primary inspection, is performed at a very high speed with respect to the entire substrate S.

Defects found in the initial inspection are secondarily inspected precisely in the review substrate inspection apparatus 10 as in the embodiment of the present invention. Then, through this review inspection, information about the inspection target is finally obtained. This inspection information may be whether or not the inspection object is defective, other foreign matter, or repairable error, and may be various information related to the yield of the substrate (S).

Hereinafter, the configuration of a substrate inspection apparatus according to an embodiment of the present invention will be described in more detail with reference to the drawings.

1 and 2, a substrate inspection apparatus 10 according to an embodiment of the present invention includes a substrate transfer unit 20 for transferring a substrate S, a transfer unit 20 for transferring a substrate S from above the substrate transfer unit 20, A first moving focusing unit 100, a second moving focusing unit 200, and a moving unit 100 for moving the moving focusing units 100 and 200, which move to an inspection position and perform focusing for image capturing of an inspection object, A stationary photographing unit 300 which is fixed on one side of the substrate transferring unit 20 and acquires an image of the inspection position according to a focusing result performed by the moving unit 30, And a control unit 40 for controlling operations of the units 100, 200, the moving unit 30, and the fixed photographing unit 300.

The controller 60 is connected to the control unit 40 and communicates with other external devices via a database 60 in which data on inspection objects and inspection results are stored and receives information on necessary inspection objects. And an input / output unit 50 for outputting a result of the inspection performed by the control unit 50 to another external control device.

More specifically, the substrate transfer unit 110 receives the substrate S that has undergone the mutually-inspected inspection from another substrate inspection apparatus 10, and transfers the substrate S in one direction. The substrate transfer unit 110 may be implemented by a roller conveyor system, a belt conveyor system, an air conveyor system, or an air slide unit.

The moving unit 30 is for moving the first moving focusing unit 100 and the second moving focusing unit 200 in a direction perpendicular to the direction in which the substrate S advances. The moving unit 30 moves the first moving focusing unit 100 and the second moving focusing unit 200 to the housing 110 of each of the moving focusing units 100 and 200 so that the first moving focusing unit 100 and the second moving focusing unit 200 can linearly operate independently of each other. An installed linear actuator and an LM guide and a ball screw installed for linear movement of the linear actuators.

Next, the internal structures of the moving focusing unit 100 and the stationary photographing unit 300 will be described in more detail. 3 is a view showing an optical system of a substrate inspection apparatus according to an embodiment of the present invention.

3, the first moving focusing unit 100 includes an objective lens 120 disposed inside the housing 110 and positioned close to the substrate S, and a focus adjustment unit 120 for adjusting the focusing of the objective lens 120 A voice coil motor (VCM) 130, a laser oscillating section 140 for irradiating the substrate S with a laser beam via an objective lens 120, a focusing image for receiving a laser beam reflected from the substrate S, A sensor 150 is provided.

The image sensor 150 for focusing is positioned at the uppermost portion of the interior of the housing 110 and a first beam splitter 160 is provided at a lower portion thereof. A half mirror 190 is disposed between the image sensor for focusing 150 and the first beam splitter 160 and a laser oscillating unit 140 is disposed on the side of the half mirror 190.

The laser beam emitted from the laser oscillating unit 140 is reflected by the half mirror 190 and travels toward the objective lens 120. The laser beam reflected by the substrate S is transmitted through the objective lens 120 to the half mirror 190, And then passes through the half mirror 190.

At this time, a 1/4 wave plate is installed below the half mirror 190 to allow the laser reflected from the substrate S to transmit through the half mirror 190. The half mirror 190 may be coated with a wavelength film. Therefore, the laser beam reflected by the substrate S is changed in polarization direction so that it can pass through the half mirror 190 and proceed to the upper focusing image sensor 150.

The illumination-use flash lamp 170 is provided on the side of the image sensor 150 for focusing. In an embodiment of the present invention, the illuminating glare lamp 170 may be embodied as a xenon lamp. A third beam splitter 180 is disposed below the illumination glare lamp 170 and a first beam splitter 160 is disposed on the side of the third beam splitter 180. The optical axis of the illumination flash and the optical axis of the laser are coaxial with respect to the inspection position of the substrate S by the third beam splitter 180 and the first beam splitter 160. [

The second beam splitter 161 is disposed below the first beam splitter 160 and the voice coil motor 130 and the objective lens 120 are positioned below the second beam splitter 161 .

The laser beam for auto focusing is reflected by the substrate S and then proceeds to the image sensor 150 for focusing. The illumination light is reflected by the substrate S and then reflected by the second beam splitter 161, (300).

In other words, the laser light and the illumination light reflected by the substrate S must have polarization components opposite to each other. To this end, a plurality of optical devices for polarization can be provided in the optical system so that the polarization components of the laser and the illumination light are realized by P waves or S waves. Accordingly, the laser light for auto focusing and the illumination light for the inspection image are separately obtained from the image sensor for focusing 150 and the image sensor for inspection 320, respectively.

The second moving focusing part 200 is substantially identical in configuration to the first moving focusing part 100 and is moved in a second direction to prevent the optical path for image acquisition with the first moving focusing part 100 from overlapping. The beam splitter (not shown) of the focusing unit 200 is provided at a position different from that of the second beam splitter 161 of the first moving focusing unit 100. A transmission window 111 through which the illumination light reflected by the second moving focusing unit 200 can travel to the fixed photographing unit 300 may be formed in the housing 110 of the first movement focusing unit 100 have.

Next, the fixed photographing unit 300 includes a housing 310 fixed to the frame 11 of the substrate inspection apparatus 10. [ The inspection image sensor 320 is located at the uppermost position inside the housing 310. A reflection mirror 330 for reflecting the image of the inspection position of the substrate S provided from the first moving focusing part 100 to the inspection image sensor 320 is installed under the inspection image sensor 320 do.

A zoom optical system 350 is provided between the reflection mirror 330 and the inspection image sensor 320. A beam splitter 340 is provided between the zoom optical system 350 and the reflection mirror 330 to reflect the image provided by the second moving focusing unit 200 to the image sensor 320 for inspection.

The database 60 may be connected to another substrate inspection apparatus (not shown) or other control apparatus through a input / output unit 50 by wire or wirelessly. The database 60 receives and stores inspection coordinates for the substrate S primarily inspected by another substrate inspection apparatus. At this time, the received information may include other information about the defect, for example, the kind of the estimated defect, and the like.

5 is a view for explaining the operation of a substrate inspection apparatus according to another embodiment of the present invention. 5, the apparatus for inspecting a substrate 10 according to another embodiment of the present invention includes two fixed image pickup units 300 and 600 and a plurality of movable focusing units 100, 200, and 400 500) may be provided in total, so that the inspection of the substrate S can be performed at a faster inspection speed. In another embodiment of the present invention, inspection can be performed on two or more positions at the same time, so that the close inspection of the substrate S can be performed at an inspection speed two times faster theoretically.

Hereinafter, embodiments of a substrate inspection method using the substrate inspection apparatus 10 according to an embodiment of the present invention constructed as described above will be described.

6 is a view for explaining a substrate inspection method according to an embodiment of the present invention. As shown in FIG. 6, the substrate inspection method according to the embodiment of the present invention receives initial inspection information about a substrate S inspected at a roughly high speed in advance from the outside through the input / output unit 50, And stores the inspection information in the database 60.

Then, the control unit 40 generates a plurality of review check coordinates necessary for review review using the initial inspection information stored in the database 60 (S100). However, only one review check coordinate can be created when there is only one review check target.

Each of these review check coordinates is identified by a unique identifier. Then, a plurality of mobile focusing units 100 and 200 allocate a mobile focusing unit, which is determined to have the highest inspection efficiency, to each of the identified review check coordinates (S110)

Here, the inspection efficiency is determined by comparing the number of the review check coordinates with the number of the moving focusing units 100 and 200 to minimize the moving distance of the moving focusing units 100 and 200, ), Minimizing inspection time and maximizing the efficiency of equipment operation.

When the inspected substrate S to be inspected is transferred to the substrate transferring unit 20, the substrate transferring unit 20 advances the substrate S forward (S120). When the review inspection coordinates of the substrate S are close to the moving focusing units 100 and 200, the moving focusing unit 100 and the second moving focusing unit 200, And the corresponding focusing unit moves to the corresponding inspection coordinates.

For example, when the corresponding inspection coordinates of the substrate S are located on the first moving focusing part 100, the laser oscillating part 140 of the first moving focusing part 100 oscillates the laser. The laser beam at this time is imaged on the substrate S in a specific pattern by a filter or the like. The laser oscillated by the laser oscillating unit 140 is reflected by the reflection mirror 190 and is incident on the substrate S via the objective lens 120. Then, the image sensor 150 for focusing picks up a pattern of the laser beam formed on the substrate S.

The pattern recognition of the laser is performed by obtaining data on the amount of light in the pixels sensed by the image sensor for focusing 150 photographed with the laser, and checking whether the focus is matched on the basis of the obtained data. Then, the focusing image sensor 150 captures an image of the laser image formed on the substrate S, and at the same time, the voice coil motor 130 adjusts the focus of the objective lens 120 (S130) .

When it is determined that the focus alignment is finally made, the glare lamp 170 is operated and the illumination light is incident on the substrate S, and the image of the substrate S with respect to the inspection coordinates in the focused state is focused on the objective lens 120, The second beam splitter 161 and the reflection mirror 330 of the fixed photographing unit 300 and the zooming optical system 350 to the inspection image sensor 320. Accordingly, the inspection image sensor 320 obtains the final inspection image. (S140).

On the other hand, an enlarged and reduced image of the image with respect to the inspection coordinates can be easily obtained by zooming in and out of the zoom optical system 350 of the fixed photographing unit 300. At this time, a method of obtaining an image is performed by focusing operation of the above-described mobile focusing parts 100 and 200 and incidence of illumination light.

When a plurality of inspection coordinates of the substrate S are set and inspection coordinates of the respective substrates S are inspected using a plurality of the moving focusing units 100 and 200, (200) individually match the inspection coordinates to be inspected. Then, each of the moving focusing units 100 and 200 is independently moved to perform focusing on a plurality of inspection coordinates.

When inspection is performed for a plurality of inspection coordinates at substantially the same time, images transmitted from the plurality of mobile focusing units 100 and 200 are not simultaneously transmitted to one fixed photographing unit 300, The incidence time of the illumination light can be set differently so as to be transmitted at another time.

5, the fixed image pickup units 300 and 600 may simultaneously acquire inspection images when the plurality of fixed image pickup units 300 and 600 are used.

In the substrate inspection apparatus 10 according to the embodiment of the present invention and the substrate inspection method using the same, since the distance between the inspection coordinates and the laser oscillation unit is always kept constant by the moving focusing unit, the accuracy of laser focusing can be maintained uniform Also, a plurality of moving focusing units can be used to secure simultaneous focusing states for a plurality of inspection coordinates and obtain a rapid inspection image.

The embodiments of the present invention, which are described above and shown in the drawings, should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

20: substrate transfer section
30 ... movable part
40 ... control unit
50 ... input / output unit
100 ... first focusing point
200 ... Second moving focusing section
300 ... fixed photographing unit

Claims (9)

A substrate transferring unit for transferring the substrate;
A moving focusing unit moving the substrate from one side of the transmitting unit to the inspection position of the substrate to perform focusing for photographing;
A moving part for moving the moving focusing part;
A stationary photographing unit for acquiring an image of the inspection position according to a focusing result of the moving unit, the substrate being fixed to one side of the transmitting unit;
And a control unit for controlling operations of the substrate transferring unit, the moving focusing unit, the moving unit, and the fixed photographing unit.
[2] The apparatus of claim 1, wherein the moving focusing unit comprises: an objective lens close to the substrate; a motor for controlling the focusing of the objective lens; a laser oscillator for irradiating the laser beam toward the substrate through the objective lens; And an image sensor for focusing the laser beam reflected from the substrate.
3. The apparatus according to claim 2, wherein the moving focusing unit includes a beam splitter provided between the objective lens and the image sensor for focusing to provide an optical axis to the fixed photographing unit, The substrate inspection apparatus comprising:
The substrate inspection apparatus according to claim 2, wherein the moving focusing unit includes a flare lamp, and an optical system for causing an optical axis of the flare lamp and an optical axis of the laser to be coaxial with respect to an inspection position of the substrate, .
The apparatus according to claim 1, wherein the stationary photographing unit comprises: a reflection mirror for reflecting an image of an inspection position of the substrate provided from the moving image focusing sensor to the inspection image sensor; And a zoom optical system provided between the sensors.
6. The apparatus according to claim 5, wherein the moving focusing portion includes a first moving focusing portion and a second moving focusing portion, each of which is independently moved by the moving portion, and wherein the reflecting mirror of the stationary photographing portion And a beam splitter is provided between the reflection mirror and the zoom optical system for reflecting the image provided by the second moving focusing unit to the inspection image sensor, .
Receiving initial inspection information on a substrate previously inspected from the outside and setting inspection coordinates of the substrate necessary for a review inspection;
Selectively moving the substrate and the moving focusing unit such that the moving focusing unit is positioned at the inspection coordinates of the substrate;
Performing focusing using the laser in the moving focusing unit with respect to the inspection coordinates of the substrate;
And when the focusing is completed, operating the lamp to transmit an image of the inspection coordinates of the substrate to a stationary photographing unit fixed at a predetermined position through the moving focusing unit to photograph an image.
The apparatus according to claim 7, wherein a plurality of inspection coordinates of the substrate are set, inspection coordinates of each of the substrates are individually matched to a plurality of the moving focusing parts, and each of the plurality of moving focusing parts is independently moved, A method of inspecting a substrate for performing focusing on inspection coordinates.
The method according to claim 8, wherein the time for acquiring an image in each of the moving focusing portions is prevented from proceeding at the same time so that an image is prevented from being simultaneously transmitted to the fixed photographing portion in each of the moving focusing portions.

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