KR20120075349A - Substrate processing method - Google Patents

Abstract

PURPOSE: A substrate processing method is provided to rapidly process after searching the alignment MARK in case the alignment MARK cannot be detected due to deformation of the substrate. CONSTITUTION: A substrate processing method comprises the following steps: loading the substrate in which the alignment MARK is given on a table; obtaining location information of the substrate from the alignment MARK recorded by a camera based on a reference location for recording the alignment MARK; and processing the substrate after setting the processing location of the substrate by a processing tool based on the location information. The substrate processing method searches the align MARK image by moving the camera or the table in case the alignment MARK image is not detected in the image. The substrate processing method revises the processing location using the processing tool by calculating the spatial deviation value of the imaging location and reference location for recording image.

Description

Substrate Processing Method {SUBSTRATE PROCESSING METHOD}

TECHNICAL FIELD This invention relates to the method of performing a board | substrate process by a processing tool based on the alignment mark provided to the board | substrate. The present invention is a substrate processing method that is particularly useful for substrates that are susceptible to deformation, such as low temperature calcined ceramic (LTCC) substrates.

Patent Document 1 discloses a processing method for forming a scribe groove by rolling a cutter wheel (also referred to as a scribing wheel) on the surface of a substrate while rolling a cutter wheel in order to segment the glass substrate.

5 is a perspective view showing an example of a conventional scribe device. The scribe apparatus 31 is equipped with the table 32 which mounts the board | substrate W. As shown in FIG. The table 32 is movable in the Y direction along the horizontal rail 33 and is driven by a ball screw 35 that is rotated by the motor 34. In addition, the table 32 is rotatable in a horizontal plane by the drive unit 36 incorporating a motor.

The bridge 39 supported by the support pillars 37 standing up on both sides with the table 32 therebetween supports the guide bar 38 extending in the X direction. The scribe head 41 is driven by the motor 42 and is mounted so as to be movable in the X direction along the guide groove 40 formed in the guide bar 38. The holder 42a is attached to the scribe head 41, and the tool 42 (cutter wheel) for a process is hold | maintained by this holder 42a. The machining tool 43 is capable of adjusting the blade tip direction. The table 32 is moved in the Y direction or the scribe head 41 is moved in the X direction along the guide groove 40 while the processing tool 43 is lowered and the blade tip is pressed against the substrate W. 6, the scribe groove S _{1 in the} X direction and the scribe groove S _{2 in the} Y direction are formed in the lattice shape on the substrate W. As shown in FIG.

Moreover, the camera 44 is provided in the upper part of the bridge 39, and the focus can be adjusted by moving up and down by manual operation. The image picked up by the camera 44 is displayed on the monitor 45.

An alignment mark (cross mark) for specifying a position is formed at the corner of the substrate W mounted on the table 32, and the camera 44 captures the substrate in the vicinity of the alignment mark. Detect location. Specifically, the shape data (cross-shaped data) of the alignment mark is stored in advance in the scribing apparatus, and the alignment mark image is compared by comparing the image data of the substrate captured by the camera 44 with the stored shape data. It is determined by pattern recognition whether or not is imprinted in the image. When it is determined that the alignment mark image has been taken, it is determined that the substrate is loaded at the correct position, and the scribe head 41 is moved to the predetermined processing start position to start the scribing operation.

If the alignment mark image is not detected in the image, it is determined that the substrate is out of the correct position, and an error message for prompting correction of the substrate position is issued. As a result, the operator manually adjusts the substrate position while correcting the position shift while confirming the image captured by the camera 44 with the monitor 45.

In addition, in the scribing apparatus 31 of FIG. 5, the positioning reference pin 46 for guiding a board | substrate is provided so that it may protrude on a table surface. By mounting this end face of the board | substrate W in contact with this reference pin 46, the alignment mark of the board | substrate W is not largely deviated from the imaging visual field range which can be taken by the camera 44. As shown in FIG.

Japanese Patent No. 3078668

However, when the substrate to be processed is an LTCC substrate, there are the following problems. LTCC board | substrate is a board | substrate which wired the conductor to the sheet which mixed the aggregate of alumina and a glass compound, and makes it a multilayer film, and this multilayer film is baked at the temperature of 1000 degrees C or less normally, for example, about 800 degreeC. Although the alignment mark is formed before firing, it tends to deform and shrink as shown by the virtual lines of FIGS. 4A and 4B during firing. When deformation | transformation of a board | substrate generate | occur | produces, the position on the board | substrate of alignment mark A will deviate from the position (design value) originally designed. Therefore, if the substrate W is accurately loaded at the position on the table where the alignment mark A is to be taken within the imaging visual field range of the camera, the alignment mark A will deviate from the imaging visual field range of the camera and be detected by the influence of the substrate deformation. It becomes impossible and becomes error display.

In this case, the substrate is manually moved to a position where the image of the alignment mark A can be detected, but once the automatic operation is stopped and the position is corrected, the work is complicated and the time loss is large.

On the other hand, if the loading position of the board | substrate W is guide | induced by providing the positioning reference pin 46 in the table surface, the frequency | count of occurrence of an error display can be reduced, but in that case, the presence of the reference pin 46 is scribed. There also existed a drawback that the range of movement of the tool 43 for a process used in this invention was restrict | limited, and a restriction | limiting was added to the processable area | region.

Accordingly, an object of the present invention is to search for alignment marks without interrupting the operation of the apparatus when the alignment marks cannot be detected due to deformation of the substrate, to detect the image containing the alignment marks, and to continue the machining operation. It is to provide a substrate processing method that can be done.

Moreover, although it becomes frequent when a positioning reference pin is not provided on a table, even if the loading position of a board | substrate shifts slightly, it aims at providing the board | substrate processing method which made it easy to detect an alignment mark. do.

In the scribing method of the present invention made to solve the above problems, an alignment mark image picked up by a camera at an imaging reference position set to mount a substrate provided with an alignment mark on a table and to image the alignment mark ( Is a substrate processing method of acquiring position information of a substrate from an image including an alignment mark image and processing the substrate after determining a machining position on the substrate by a machining tool based on the position information, and imaging at an imaging reference position. When the alignment mark image is not detected, the camera or the table is moved so that the imaging position is sequentially moved around the imaging reference position so that the alignment mark image is searched, and the imaging position when the alignment mark image is detected. Calculate the position shift amount of the imaging reference position And it is adapted to correct the processing position by the processing tool.

In the method of the present invention, when the alignment mark cannot be detected at the imaging reference position due to the deformation of the substrate, the alignment mark image is searched by moving the camera or the table to move the imaging position sequentially around the imaging reference position. do. As a result, even when the alignment mark image cannot be detected in the imaging visual field range at the first shooting reference position, the camera or table is sequentially moved to the peripheral imaging position to search in the same imaging visual field range. It is possible to detect the mark image, calculate the position shift amount between the imaging position and the imaging reference position when the alignment mark image was detected, and correct the machining position by the machining tool based on this position shift amount. The operation of the machining can be continued. As a result, troublesome manual labor such as position correction of the substrate can be eliminated, and work time can be reduced.

Further, even if the alignment mark is slightly shifted from the photographing reference position, the alignment mark image can be detected, and the deviation position between the imaging position and the reference setting position where the alignment mark image was detected can be calculated to determine the machining position. As a result, there is no need to provide a positioning reference pin on the table as in the prior art, and the reference pin does not interfere with the machining tool, so that the machining tool can be freely moved to the periphery of the substrate.

(Means and effects to solve other problems)

In the above invention, it is preferable to move the imaging position sequentially in a vortex shape around the imaging reference position when searching for the alignment mark image.

Thereby, even if the alignment mark was moved in which direction on the table, the alignment mark can be searched.

In the above invention, the imaging visual field range at each imaging position by the camera may be circular or rectangular, and the imaging positions may be moved so that the imaging visual field ranges of adjacent imaging positions overlap each other at the peripheral part of the visual field.

Thereby, an alignment mark image can reliably enter the imaging visual field range in any adjacent imaging position, and can detect a detection defect.

In the above invention, it is preferable that the detectable region of the alignment image determined by the moving range of the imaging position of the camera and the imaging visual field range contains at least 5 mm horizontally and centering on the shooting reference position.

Since mounting a board | substrate to a table with a positional accuracy of about 5 mm can be performed easily, an alignment mark can be detected reliably by making at least 5 mm vertically and horizontally centering around a photography reference position. Therefore, even if there is no reference pin for positioning provided in the conventional apparatus, it can be easily aligned. In addition, by making the reference pin unnecessary, problems (such as interference with scribe means) caused by the reference pin can be prevented.

In the above invention, the substrate may be an LTCC substrate.

In the LTCC substrate, the alignment mark is deformed during firing, but in this case, the alignment mark can be easily detected.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows an example of the scribe apparatus for implementing one Example of the substrate processing method which concerns on this invention.
FIG. 2 is a diagram showing an example of a movement order of an imaging position centered on an imaging reference position when searching for an alignment mark image. FIG.
3 is a block diagram showing a control system of the scribe device;
4 is a plan view showing a modified state of the LTCC substrate;
5 is a perspective view showing an example of a conventional scribe device.
6 is a plan view showing a scribed substrate in a lattice shape;

Below, the substrate processing method of this invention is demonstrated in detail based on the Example which scribes an LTCC board | substrate.

1 is a perspective view showing an example of a scribing apparatus for scribing an LTCC substrate. This scribe device 1 is provided with the table 2 which can hold | maintain the LTCC board | substrate W by an adsorption mechanism (not shown). The table 2 is able to move along the rails 3 and 3 in the Y direction by driving the ball screw 4 by the motor M ₁ . Moreover, the table 2 is able to rotate in the horizontal plane by the drive part 5 in which the motor was built.

The bridge 8 supported by the support pillars 6 and 6 standing up on both sides with the table 2 interposed therebetween supports the guide bar 7 extending in the X direction. The scribe head 10 is driven by the motor M ₂ and is able to move along the guide groove 9 formed in the guide bar 7 in the X direction.

The holder 11 is attached to the scribe head 10. In this holder 11, a dedicated cutter wheel (tool for processing) 12 for scribing the substrate W is held. The cutter wheel 12 can adjust the angle of the blade edge | tip (relative direction of travel with respect to a board | substrate) to an X direction and a Y direction. Then, the cutter wheel 12 is lowered and the substrate W is transferred in the Y direction while the blade tip is pressed against the substrate W, or the scribe head 10 is moved in the X direction along the guide 7. The scribe grooves in the X and Y directions can be formed.

In addition, the scribe head 10 is provided with a camera 13 which moves integrally with the cutter wheel 12. Focus can be adjusted by moving this camera 13 up and down. The distance between the camera 13 and the cutter wheel 12 is previously measured, and the position in the image taken by the camera 13 and the position of the cutter wheel 12 correspond one-to-one. The image data picked up by the camera 13 is displayed on the monitor 14 and output to the image processing unit 21 (see FIG. 3) described later.

An alignment mark A (see FIG. 4) for specifying the position of the substrate W is formed at the corner of the substrate W stacked on the table 2, and the substrate W is formed by the camera 13. By imaging (in the vicinity to which the alignment mark A is attached), the image (also called alignment mark image) in which the alignment mark image is included is detected, and the position of the alignment mark A of the board | substrate W is detected by this. Specifically, a process of extracting a pattern of alignment mark A is performed by the image processing unit 21 of the control system 20 described later from the captured image, and contrasts with the shape data (cross mark) of the alignment mark stored in advance. By doing this, the position of the alignment mark A is detected.

In addition, the camera 13 (and the scribe head 10) has the origin position determined as a reference, and the motor M _{1 when} the position detection of the alignment mark A of the substrate W mounted on the table 2 is performed. , M ₂ ) is returned to the home position, and imaging is performed at the home position. Since the position of the camera 13 in the origin return state becomes the first imaging position at the time of the operation for searching for the alignment mark A, this is referred to as the "photographing reference position".

3 is a block diagram showing the control system 20 of the scribe device 1. The image data signal output from the camera 13 is supplied to the control unit 22 as the alignment mark matching image data through the image processing unit 21. The input part 23 is an input device which can input various processing programs, such as a scribing operation | movement of the board | substrate W, and the search program used for detecting the position of an alignment mark is also input. The control unit 22 is connected to an X-direction motor driver 24, a Y-direction motor driver 25, a table rotation motor driver 26, a scribe head driver 27, and a data holding area 28 (memory). . In the data holding area 28, shape data (cross data) necessary for matching the alignment mark by pattern recognition is stored in association with the position detection together with various processing programs.

The control unit 22 controls the position in the rotation axis direction of the table 2 in the X direction of the scribe head 10 on the basis of the processing program input from the input unit 23 and the setting parameter data required for the scribe operation in advance. To control the movement of the table 2 in the Y direction. In addition, during scribing by the cutter wheel 12, the cutter wheel 12 is controlled to press-contact the surface of the substrate W with an appropriate load.

In addition, when searching for the alignment mark A with respect to the board | substrate W, the operation which contrasts the shape data of the alignment mark stored in the data holding area 28, and the image extracted by the image processing part 21 is performed.

Next, the search operation of the alignment mark performed by the control unit 22 will be described. Although the tolerance of position detection can be arbitrarily changed as a parameter of the control program of the apparatus, in this embodiment, the tolerance of position detection is set to 1 mm, and the imaging visual field range of the camera 13 is the magnification of the camera (70 times). In relation to the above, one side is defined as a rectangular region of 2 mm. That is, when the board | substrate is imaged in a certain imaging position, if the center position (center of a cross mark) of the alignment mark is imprinted in the imaging visual field range, it will be judged that alignment mark A could be detected in the imaging position.

First, the board | substrate W is imaged with the camera 13 returned to the origin position. At this time, the camera 13 captures a rectangular region having a diameter of 2 mm in the imaging visual field range at the imaging reference position. The image picked up by the camera 13 and the shape data of the alignment mark stored in the data holding area 28 are collated, and the image of the alignment mark A is pattern-recognized in the image, and the center of the mark is within the imaging visual field range. If it is, it is determined that alignment mark A could be detected, and it is determined that the position of the substrate W is within an allowable error at the imaging reference position. Then, the cutter wheel 12 (machining tool) is moved to a desired machining start position set in advance to start a scribing operation.

If the image of the alignment mark A is not taken in the imaging visual field range at the imaging reference position, or the center of a mark is out of the imaging visual field range, it is determined that it is out of a reference setting position. In that case, the camera 13 or the table 2 is arbitrarily pitched from the imaging reference position to its periphery via the X-direction motor driver 24 and the Y-direction motor driver 25 (as a parameter of the control program of the driver). Although it can be set, it is usually set arbitrarily in consideration of the relationship between the size of the alignment mark and the imaging visual field range of the camera, and is moved by about 1.8 mm) in this embodiment. The pitch of the movement is shorter than the diameter (2 mm) of the imaging visual field range in order to search for the alignment mark image while the peripheral portion of the imaging visual field range overlaps with the visual field range at the previous imaging position.

FIG. 2 is a diagram showing the movement order (search order) of the imaging position with respect to the substrate W by the camera 13, and numbers (1) to (25) given to FIG. It is shown. The imaging visual field range of the camera 13 becomes a rectangular area | region with one side 2 mm, and the number 1 which is located in the center is set as the "imaging reference position" which is an initial imaging position. This imaging reference position is the origin position of the camera 13 as mentioned above.

When the substrate W is imaged at the imaging reference position [number (1)], when the alignment mark image is not in the imaging visual field range and the alignment mark image is not detected, the camera 13 or the table 2 Then, the imaging position is moved to the number 2 by moving one pitch (1.8 mm) to the left. Subsequently, as shown by the arrow in Fig. 2B until the alignment mark image is detected, the periphery is moved in a vortex around the imaging reference position [number (1)] and (1) → (2) → (3). The imaging position is moved in the order of (25).

For example, when an alignment mark image is detected at the imaging position of the number 20, the control unit 22 calculates the total sum of the position shift amounts from the imaging reference position (number (1)) to the number (20). The calculation result is used for automatic correction of the machining start position of the cutter wheel 12, and the scribe operation is started by moving the cutter wheel 12 to the machining start position after the correction.

In this way, even though the alignment mark image can be detected by the imaging at the original imaging reference position, even if it cannot be detected by the deformation of the substrate W or the like, the operation of the apparatus is automatically stopped without interruption. The scribe operation can be continued by searching for and detecting the alignment image, thereby eliminating the troublesome work such as the position correction of the substrate W and eliminating the loss of the work time.

Further, even when the alignment mark image cannot be detected at the imaging reference position, the image pickup position is sequentially moved in a predetermined pitch and in a predetermined movement order so that the search can be performed so that the alignment mark image can be detected. Positioning reference pins for positioning on the table eliminate the need to load the substrate correctly. Therefore, there is no possibility that the positioning reference pin and the scribe head 10 collide with each other, and the scribe head 10 can be freely moved to the periphery of the substrate W. FIG.

In the present embodiment, the range for searching by moving the imaging position is limited to 5 mm in length and width, so that if an alignment mark exists within the range, it can be reliably found. It may be widened widely. In addition, although the one-time moving pitch at the time of searching was set to about 1.8 mm by the control parameter of a control program, you may adjust a pitch according to a tolerance. At this time, it is preferable that a part of the previous imaging visual field range is overlapped so as to eliminate the blind area where the alignment mark cannot be detected. In addition, in this embodiment, although the imaging visual field range was made into the rectangular area | region, you may make it circular. In the case of a rectangle, it becomes easy to eliminate the rectangular area.

In addition, although the search of the alignment mark image by the camera 13 is made to include the area | region of 5 mm in length and width, if it is this range, the deviation of the alignment mark by the deformation | transformation of an LTCC board | substrate can fully be covered.

In the above embodiment, the camera 13 is integrally attached to the scribe head 10, but may be mounted on the bridge 8. What is necessary is just to be able to correspond the positional relationship of the camera 13 and the machining tool 12 one-to-one.

As mentioned above, although the typical Example of this invention was described, this invention is not necessarily specific only to the Example mentioned above. For example, it is applicable to the whole brittle material board | substrates, such as a glass substrate, a semiconductor substrate, a thin film solar cell substrate, in addition to the LTCC board | substrate which is easy to deform | transform as a process target substrate. In addition to the cutter wheel, the machining tool 12 mounted on the scribe head 11 may be a fixed blade having a directional direction at the blade edge, or the like. In the case of performing a laser scribe, the laser beam is condensed into a beam spot and then the substrate It may be an optical tool having an optical system for irradiating

INDUSTRIAL APPLICABILITY The present invention can be applied to a substrate processing apparatus such as a scribing apparatus for forming a scribe groove in a substrate such as an LTCC substrate.

A: alignment mark
W: substrate
1: scribe device
2: table
13: camera
20: control system
22: control unit

Claims (5)

The board | substrate with which the alignment mark was provided is mounted on a table, the positional information of the said board | substrate is acquired from the alignment mark image imaged by the camera in the imaging reference position set for imaging the said alignment mark, and based on the positional information Is a substrate processing method for processing the substrate after determining the processing position on the substrate by the processing tool,
In the imaging at the imaging reference position, when the alignment mark image is not detected, the alignment mark image is searched by moving the camera or the table so that the imaging position is sequentially moved around the imaging reference position. A substrate processing method characterized by calculating a position shift amount between an imaging position and an imaging reference position when the alignment mark image is detected to correct a machining position by the machining tool. The substrate processing method according to claim 1, wherein, during the search for the alignment mark image, the imaging position is sequentially moved around the imaging reference position in a vortex shape. 3. The imaging position range according to claim 1 or 2, wherein the imaging visual field range at each imaging position by the camera is circular or rectangular, and the imaging positions are moved so that the imaging visual field ranges of adjacent imaging positions overlap each other at a peripheral portion of the visual field. Substrate processing method which was made to let. The detectable area of the alignment image determined by the moving range of the imaging position of the camera and the imaging visual field range includes at least 5 mm horizontally and centered on the shooting reference position. Substrate processing method. The substrate processing method according to claim 1 or 2, wherein the substrate is an LTCC substrate.

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