TW201804266A - Position detection device and position detection method including using at least one camera to obtain image information - Google Patents

Abstract

The invention provides a position detection device configured to position a substrate from both sides of the substrate. A supporting element is configured to support the substrate. At least one camera is configured to take photos of the substrate supported by the supporting element. A processor is configured to obtain position information of the substrate based on a first image taken by one camera from an edge part of the substrate supported by the supporting element. Then, position information of an up side down substrate is obtained based on a second image taken by one camera from an edge part of the up side down substrate supported by the supporting element, the first image, and the position information of the substrate obtained with the first image.

Description

Position detection device and method

The invention relates to a position detection device and a position detection method.

A technique for positioning a substrate using an alignment mark formed on the substrate when drawing and processing the substrate is known. In the case of drawing and processing on both sides of the substrate, it is desirable that the drawing position and processing position of the front and back are consistent with each other. Since the alignment mark is embedded in the inner layer of the substrate and an alignment mark is detected from both sides, positioning can be performed on both sides of the front and back.

As a method of detecting the alignment mark of the inner layer from both sides, a method of irradiating strong light to make the alignment mark protrude and a method of performing counter boring until the alignment mark is exposed can be considered.

Patent Document 1 below discloses a screen printing technique for positioning a substrate based on image data obtained by photographing the vicinity of a corner portion of the substrate.

(Prior technical literature) (Patent Literature)

Patent Document 1: Japanese Patent Application Laid-Open No. 2014-205286

For a substrate on which an alignment mark is not formed on the inner layer, a method of positioning the substrate by detecting the alignment mark from both sides cannot be applied. Patent Document 1 discloses a technique of positioning only on one side of a substrate, but does not disclose a technique of positioning on both sides.

An object of the present invention is to provide a position detection device and a position detection method capable of positioning a substrate on both sides of the substrate.

According to an aspect of the present invention, there can be provided a detection device including: a support portion, a support substrate; at least one imaging device that photographs the substrate supported by the support portion; and a processing portion, wherein the processing portion is based on a The imaging device obtains a first image obtained by photographing a corner portion of the substrate supported by the supporting portion, and obtains position information of the corner portion. The second image obtained by shooting the corner portion of the substrate, the first image, and the position information of the corner portion obtained based on the first image, and the corner of the substrate with the front and back flipped is obtained. Location information.

According to another aspect of the present invention, a position detection method may be provided, in which a first image is acquired by photographing a corner portion of a substrate from a first surface side of the substrate, and based on the first image, obtaining The position information of the corner portion when the first surface side of the substrate is viewed, the second corner of the substrate is photographed from the second surface side of the side opposite to the first surface to obtain a second image. Image, based on the first image, the second image, and the position information of the corner portion of the substrate obtained from the first image, and the image obtained when viewed from the second surface side of the substrate is obtained. Corner location information.

The first image obtained by photographing the corners of the substrate, the second image obtained by photographing the same corners of the substrate with the front and back flipped, and the position information of the substrate obtained from the first image Since the position information of the aforementioned substrate with the front and back flipped is obtained, the corners can be set as common reference points on both sides of the substrate. Compared with the method of detecting the position of the corner by performing image analysis on the first image and the second image, it is possible to reduce the deviation of the common reference point on both sides of the substrate.

10‧‧‧ support

11A, 11B‧‧‧ Camera

12‧‧‧ Processing Department

13‧‧‧Memory Department

15A, 15B‧‧‧Camera range

16A, 16B‧‧‧Lifting mechanism

20‧‧‧ abutment

21‧‧‧ mobile agency

23‧‧‧stage

24‧‧‧ Door Frame

26‧‧‧ Inkjet Head

30‧‧‧Control device

31‧‧‧Memory device

35‧‧‧ input device

36‧‧‧Output device

50‧‧‧ substrate

51‧‧‧ Corner of substrate

55‧‧‧ Image of the corner of the substrate and its surroundings (first image)

55a‧‧‧1st flip image

55b‧‧‧template

56‧‧‧ Image of the corner of the substrate and its surroundings (second image)

57‧‧‧face

61‧‧‧Support substrate

62, 63‧‧‧ conductive film

DF‧‧‧ Depth of Field

FIG. 1A is a schematic perspective view of a position detection device according to an embodiment, FIG. 1B is a diagram illustrating a step of inverting a front surface and a back surface of a substrate, and FIG. 1C is a schematic perspective view after the substrate of the position detection device according to the embodiment is inverted.

FIG. 2A is a diagram showing an example of a first image of a corner portion of a substrate and its surroundings, and FIG. 2B is a diagram showing an example of a second image of a corner portion of a substrate and its surroundings.

FIG. 3 is a diagram for explaining a method of detecting a position of a corner portion of a substrate based on a first image and a second image.

FIG. 4 is a diagram for explaining an example in which a matching error occurs.

FIG. 5A and FIG. 5B respectively show the inside of the substrate photographed by the imaging device. Part of the sectional view.

FIG. 6 is a schematic front view of a film forming apparatus according to another embodiment.

FIG. 7 is a plan view of a substrate used in the auxiliary embodiment shown in FIG. 6, and FIG. 7B is a cross-sectional view taken along a dotted line 7B-7B in FIG. 7A.

FIG. 8 is a flowchart of a method of forming a photoresist pattern for etching on a substrate used in the embodiment assisted in FIG. 6.

Referring to FIG. 1A to FIG. 4, a position detection device and a position detection method according to the embodiment will be described.

FIG. 1A is a schematic perspective view of a position detection device according to an embodiment. The position detection device based on this embodiment includes a support portion 10, imaging devices 11A and 11B, a processing portion 12, and a memory portion 13. The support portion 10 supports a substrate 50, which is a processing object, on an upper surface (support surface) thereof. The imaging device 11A captures an image in the imaging range 15A on the support surface of the support portion 10 to obtain image data. The imaging device 11B captures another range of the support surface of the support portion 10 to obtain image data. The processing unit 12 implements a function of position detection by executing a processing program stored in the memory unit 13. In the memory unit 13, in addition to the processing program, image data acquired by the imaging devices 11A and 11B or processing results of the processing unit 12, that is, coordinate data, are also stored. The planar shape of the substrate 50 has a plurality of corners.

Next, a method of detecting the position of the substrate 50 using the position detection device shown in FIG. 1A will be described.

First, as shown in FIG. 1A, the supporting surface of the supporting portion 10 supports the substrate 50. The relative position of the substrate 50 and the imaging device 11A is adjusted so that one corner 51 is accommodated in the imaging range 15A. In this adjustment, the support unit 10 can be moved or the imaging device 11A can be moved by an instruction from the processing unit 12. In this state, the imaging device 11A captures an area including the corner portion 51 of the substrate 50. The processing unit 12 captures an image (hereinafter, referred to as a first image 55) obtained by the imaging device 11A. The processing unit 12 stores the image data of the first image 55 taken from the imaging device 11A in the storage unit 13.

An example of the first image 55 is shown in FIG. 2A. The first image 55 includes a corner portion 51 of the substrate 50 inside. The processing unit 12 (FIG. 1A) performs image analysis of the first image 55 to detect the position of the corner portion 51 within the imaging range 15A. An example of the position detection procedure is described below.

The processing unit 12 first extracts the outline of the substrate 50. Thereafter, straight lines are used to approximate one pair of edges of the corner portion 51 respectively. The coordinates of the intersection of the two straight lines obtained by the approximation are set as the coordinates of the corner portion 51. Based on the coordinates of the corner portion 51 and the relative positional relationship between the support portion 10 and the imaging device 11A, position information of the corner portion 51 (for example, coordinates in an alignment coordinate system fixed with respect to the support portion 10) is obtained. Similarly, the position and posture related to the in-plane direction of the substrate 50 are determined by determining position information of at least one other corner. The processing unit 12 (FIG. 1A) stores the calculated position information of the corner portion 51 and other corner portions in the memory portion 13 (FIG. 1A).

After the position and orientation of the substrate 50 is determined, a surface (hereinafter, referred to as a first surface) facing the substrate 50 is processed. This process is, for example, a process of forming a film having a desired pattern.

Next, as shown in FIG. 1B, the front and back surfaces of the substrate 50 are reversed, and the supporting surface of the supporting portion 10 supports the substrate 50. Thereby, the second surface on the side opposite to the first surface of the substrate 50 faces upward.

As shown in FIG. 1C, the relative position of the substrate 50 and the imaging device 11B is adjusted so that the corner portion 51 of the substrate 50 is accommodated in the imaging range 15B of the imaging device 11B. In this type of adjustment, the support unit 10 can be moved or the imaging device 11B can be moved by an instruction from the processing unit 12. In this state, the imaging device 11B captures an area including the corner portion 51 of the substrate 50. The processing unit 12 captures an image (hereinafter, referred to as a second image 56) acquired by the imaging device 11B.

An example of the second image 56 captured by the imaging device 11B is shown in FIG. 2B. The second image 56 includes a corner portion 51 of the substrate 50 and a peripheral portion thereof. In the first image 55 shown in FIG. 2A, the substrate 50 is displayed in the lower left area of the entire image. In the example shown in FIG. 2B, the substrate 50 is displayed on the entire image because the substrate 50 is reversed by the front and back. Lower right area.

The processing unit 12 obtains the angle in the second image 56 based on the coordinates of the corner portion 51 of the substrate 50 in the first image 55 (FIG. 2A), the second image 56 (FIG. 2B), and the first image 55. The coordinates of the part 51. Hereinafter, a method of obtaining the position information of the corner portion 51 of the substrate 50 with the front and back flipped will be described with reference to FIG. 3.

As shown in FIG. 3, a first flip image 55a is obtained by mirror-converting the first image 55. A part of the image including the substrate 50 and the corner portion 51 is cut out from the first flip image 55a to obtain a template 55b. Pattern matching between the second image 56 and the template 55b is performed. The coordinates of the corner portion 51 in the second image 56 are calculated based on the coordinates of the corner portion 51 in the template 55b when the similarity becomes maximum. Template 55b The coordinates of the corner 51 have been calculated using the method described with reference to FIG. 2A.

From the coordinates of the corner portion 51 in the second image 56, the position information of the corner portion 51 (for example, the coordinates in the coordinate system) is obtained. Similarly, the position and posture of the substrate 50 reversed by the front and back are determined by obtaining position information of at least another corner.

After the position and orientation in the alignment coordinate system of the substrate 50 are determined, the second surface facing upward of the substrate 50 is processed. This process is, for example, a process of forming a film having a desired pattern.

Next, an example in which a matching error may occur will be described with reference to FIG. 4.

As shown in FIG. 4, when the area of the area occupied by the substrate 50 in the first image 55 is larger than the area of the area occupied by the substrate 50 in the second image 56, the template 55 b cannot be accommodated in the second image 56. The area occupied by the substrate 50 in the middle. Therefore, in the pattern matching process, a solution with a high degree of similarity cannot be obtained, and a matching error occurs.

When a matching error occurs, the processing unit 12 (FIG. 1C) moves at least one of the support unit 10 and the imaging device 11B, and increases the proportion of the substrate 50 in the second image 56 (FIG. 2B). After that, by executing the pattern matching method shown in FIG. 3, a normal solution can be obtained in the pattern matching process.

Next, the excellent effects of the position detection device and the position detection method based on the embodiment shown in FIGS. 1A to 5B will be described.

In this embodiment, the first surface of the substrate 50 is processed and the second surface is processed. During the processing, the common corner portion 51 and the like are used as alignment reference points for positioning. Therefore, alignment of the film formed on the first surface and the film formed on the second surface can be performed. It is not necessary to form an alignment mark in the substrate 50.

The edge of the substrate 50 is not necessarily a geometrically tight straight line. Therefore, for example, when the contour of the substrate 50 in the first image 55 shown in FIG. 2A is approximated by a straight line to obtain the coordinates of the corner portion 51, if the lengths of the contours are different, the calculation may be caused. The coordinates of the outgoing corner portion 51 are also different. The corner 51 obtained from the intersection of the contour line of the substrate 50 in the second image 56 shown in FIG. 2B and the intersection of the contour line of the substrate 50 in the first image 55 in FIG. 2A appear. The corners 51 that emerge are not likely to be the same points on the substrate 50. When the two are not the same, the corner portion 51 serving as the reference position when processing the first surface and the corner portion 51 serving as the reference position when processing the second surface do not closely match. As a result, the relative positional relationship between the film formed on the first surface and the film formed on the second surface may deviate from the target relationship.

In the above embodiment, when the coordinates of the corner portion 51 of the substrate 50 in the second image 56 shown in FIG. 2B are obtained, as shown in FIG. 3, the coordinates based on the first image 55 and the second image 56 are used. Pattern matching. More specifically, the coordinates of the corner 51 of the second image 56 are not obtained from the coordinates of the intersection of the outline of the second image 56, but the coordinates and the pattern of the intersection of the outline of the first image 55 are used instead. The results of the matching are used to obtain the coordinates of the corner portion 51 of the second image 56. Therefore, before and after the front and back of the substrate 50 are reversed, the corner portions 51 determined by image analysis can be ensured to be approximately the same on the substrate 50. This makes it possible to suppress the positional deviation between the film formed on the first surface and the film formed on the second surface.

5A and 5B, a preferred depth of field of the imaging devices 11A and 11B will be described. 5A and 5B are cross-sectional views of a part of the inside of the substrate 50 which is imaged by the imaging devices 11A and 11B, respectively.

As shown in FIGS. 5A and 5B, the end surface 57 of the substrate 50 is not necessarily perpendicular to the surfaces on both sides. In the example shown in FIG. 5A, the end surface 57 in the imaging range 15A (FIG. 1A) of the imaging device 11A is inclined obliquely downward. When the front and back of the substrate 50 are reversed, the end surface 57 in the imaging range 15B (FIG. 1C) of the imaging device 11B faces obliquely upward. The imaging devices 11A and 11B include both the upper surface and the lower surface of the substrate 50 supported by the support portion 10 within the range of the depth of field DF.

By setting the depth of field DF in this way, even if the front and back surfaces of the substrate 50 are reversed, the imaging devices 11A and 11B can always be brought into focus at the outermost edges. This can ensure that the corner portion 51 obtained from the first image 55 and the corner portion 51 obtained by the pattern matching process based on the first image 55 and the second image 56 are substantially the same.

Next, various modifications of the above embodiment will be described.

In the above embodiment, the imaging device 11A that acquires the first image 55 (FIG. 2A) in the photographing process shown in FIG. 1A and the acquisition of the second image 56 (FIG. 2B) in the photographing process shown in FIG. 1C are prepared. Camera device 11B. Instead of preparing two imaging devices 11A and 11B by moving one imaging device 11A, the first image 55 (FIG. 2A) and the second image 56 (FIG. 2B) may be acquired by one imaging device 11A.

In the above embodiment, in the pattern matching process shown in FIG. 3, the first image 55 is inverted (mirror conversion), and the image is inverted from the first image. 55a cuts out the template 55b, but it is also possible to flip the second image 56 and cut out the template from the flipped second image without having to flip the first image 55. In addition, a template can be cut out from the first image 55, and pattern matching processing between the template and the image in which the second image 56 is reversed can also be performed, and the first image 55 can also be reversed, and the second image A template is cut out at 56 and pattern matching processing is performed between the template and the image in which the first image 55 is reversed.

In the above embodiment, the position and posture of the substrate 50 are obtained by obtaining the position information of at least two corners of the substrate 50, but the position information of the corners of three or more locations may also be obtained. By increasing the corners of the position detection object, the accuracy of position detection can be improved.

In the above embodiment, when the coordinates of the corner portion 51 of the substrate 50 in the first image 55 shown in FIG. 2A are obtained, the outline of the substrate 50 is detected, but other than that, the first The image 55 and the reference image are subjected to a pattern matching process to obtain the coordinates of the corner portion 51.

In the above embodiment, as shown in FIGS. 5A and 5B, as the imaging devices 11A and 11B, those having characteristics such that the upper surface and the lower surface of the substrate 50 are accommodated within the range of the depth of field DF are used. As the imaging devices 11A and 11B, a structure in which the depth of field DF is shallower than the thickness of the substrate 50 and has an autofocus function may be used instead. When the end surface of the substrate 50 is inclined, it is sufficient to control the imaging devices 11A and 11B in such a manner as to perform automatic focusing on the outer edge.

Next, referring to FIGS. 6 to 8, another embodiment will be described. In the following embodiments, the position detection device based on the embodiment shown in FIGS. 1A to 5B is applied to an inkjet-type film forming device.

FIG. 6 is a schematic front view of a film forming apparatus according to this embodiment. The stage 23 is supported by the base 20 via the moving mechanism 21. The stage 23 corresponds to the support portion 10 of the embodiment shown in FIGS. 1A and 1C. The substrate 50 is supported by the upper surface (support surface) of the stage 23. The moving mechanism 21 can move the substrate 50 in a two-dimensional direction by moving the stage 23 in a two-dimensional direction parallel to the support surface. The moving mechanism 21 and the stage 23 can use an XY stage, for example. Normally, the supporting surface of the stage 23 is kept horizontal.

Above the substrate 50 supported by the stage 23, a plurality of inkjet heads 26 and a plurality of imaging devices 11A and 11B are arranged. The inkjet head 26 and the imaging devices 11A and 11B are supported by the base 20 via a gate frame 24. The imaging devices 11A and 11B can be raised and lowered by the raising and lowering mechanisms 16A and 16B, respectively. A plurality of nozzle holes are provided in each inkjet head 26. A droplet of the film material is discharged from the nozzle hole toward the substrate 50. The imaging devices 11A and 11B photograph a part of the substrate 50 supported by the stage 23 and send image data of the acquired two-dimensional image to the control device 30. The control device 30 has a function of the processing unit 12 of the embodiment shown in FIGS. 1A and 1C. In addition, the control device 30 can raise and lower the imaging devices 11A and 11B by controlling the elevating mechanisms 16A and 16B to adjust the focal positions of the imaging devices 11A and 11B.

A film can be formed by hardening a liquid film material attached to the substrate 50. As a film material, a photocurable resin, a thermosetting resin, etc. can be used. A light source or a heat source for curing the film material attached to the substrate 50 is disposed on the side of the inkjet head 26.

The control device 30 controls the movement of the stage 23 by the moving mechanism 21 and the discharge of the film material from the nozzle holes of the inkjet head 26. The control device 30 includes The memory device 31 stores pattern data of a film to be formed in the memory device 31. The control device 30 controls the moving mechanism 21 and the inkjet head 26 based on the pattern data, whereby a film of a desired pattern can be formed on the substrate 50.

Various instructions and data are input from the input device 35 to the control device 30. The input device 35 uses, for example, a keyboard, a pointing device, a USB port, a communication device, and the like. Various information related to the operation of the film forming apparatus is output to the output device 36. The output device 36 uses, for example, a liquid crystal display, a speaker, a USB port, a communication device, and the like.

Next, referring to FIG. 7A and FIG. 7B, a substrate 50 which is a processing target will be described.

FIG. 7A is a plan view of the substrate 50, and FIG. 7B is a cross-sectional view taken along a dotted line 7B-7B in FIG. 7A. The substrate 50 includes an insulating support substrate 61 and conductive films 62 and 63 provided on both surfaces thereof. As the support substrate 61, for example, a ceramic substrate is used. As the conductive films 62 and 63, for example, copper foil is used. The outer periphery of the conductive films 62 and 63 is arranged slightly inward of the outer periphery of the support substrate 61. On the surface of the support substrate 61, it is ensured that the conductive film 62 is not provided near the edge of the support substrate 61 (inside the outer periphery). Framed area of 63.

Next, a method of forming a photoresist pattern for etching on the substrate 50 will be described with reference to FIG. 8.

FIG. 8 is a flowchart of a method of forming a photoresist pattern for etching in the substrate 50. First, in step S1, the substrate 50 is placed on the holding surface of the stage 23 and fixed by a vacuum chuck or the like. In step S2, the position of the substrate 50 is detected. In this process, the same method as that described with reference to FIGS. 1A and 2A is used to detect the position of the substrate 50.

Next, in step S3, while moving the substrate 50, the photoresist material is ejected from the inkjet head 26 (FIG. 6), and a photoresist pattern is formed on the surface (first surface) of the substrate 50 facing upward.

In step S4, the front and back of the substrate 50 supported by the stage 23 are reversed. In step S5, the position of the substrate 50 is detected. In the detection process, the method described with reference to FIG. 1C and FIG. 3 is applied, that is, the method using pattern matching processing is applied. In step S6, while moving the substrate 50, the photoresist material is ejected from the inkjet head 26 (FIG. 6), and a photoresist pattern is formed on the surface (second surface) of the substrate 50 facing upward. After that, the photoresist pattern is used as an etching mask, and the conductive films 62 and 63 are etched. After the etching, the photoresist pattern is removed.

In the processing of the first surface of the substrate 50 and the processing of the second surface, the common corner portion is used as a reference for positioning, so that the photoresist patterns formed on the first surface and the second surface can be highly accurate with each other. Degrees of alignment.

Next, a case where the depth of field of the imaging devices 11A and 11B is shallower than the thickness of the substrate 50 will be described. As shown in FIG. 5A, when the end surface of the substrate 50 is inclined, in order to focus on the outer edge, the upper surface of the substrate 50 must be accommodated in the range of the depth of field. As shown in FIG. 5B, when the end surface of the substrate 50 is inclined, it is necessary to accommodate the lower surface of the substrate 50 within the range of the depth of field. The control device 30 controls the lift mechanisms 16A and 16B so that the outer edge of the substrate 50 is accommodated in the range of the depth of field. Thereby, even in any of the cases of FIGS. 5A and 5B, it is possible to focus on the outer edge of the substrate 50. In this way, the control device 30 and the lifting mechanisms 16A and 16B serve as the image pickup devices 11A and 11B on the upper and lower surfaces of the substrate 50. Among the edges, an auto-focusing mechanism that focuses on the outer edges focuses and functions.

The above-mentioned embodiments are examples, and of course, partial replacement or combination of structures shown in different embodiments can also be performed. The same functions and effects based on the same structure of a plurality of embodiments will not be mentioned for each embodiment. In addition, the present invention is not limited to the above embodiments. For example, it will be apparent to those skilled in the art that various changes, improvements, and combinations can be made.

10‧‧‧ support

11A‧‧‧ Camera

11B‧‧‧ Camera

12‧‧‧ Processing Department

13‧‧‧Memory Department

15A‧‧‧Camera range

15B‧‧‧Camera range

50‧‧‧ substrate

51‧‧‧ Corner of substrate

Claims (6)

A position detection device includes: a support portion that supports a substrate; at least one imaging device that photographs the substrate supported by the support portion; and a processing portion that the processing portion uses the one imaging device to align the supported portion with one The first image obtained by photographing the corners of the substrate supported is used to obtain the position information of the corners, and the corners of the substrate supported by the support are performed based on the front and back flipped by a camera device. The second image, the first image, and the position information of the corners obtained based on the first image are obtained by shooting, and the position information of the corners of the substrate with the front and back flipped is obtained. The position detection device according to item 1 of the scope of patent application, wherein both the upper surface and the lower surface of the substrate supported by the support portion are included in the range of the depth of field. The position detection device according to item 1 of the scope of patent application, further comprising an auto-focusing mechanism for focusing the imaging devices 11A, 11B on the edges of the upper surface and the lower surface of the substrate 50 that are positioned further outside. Position detection device as described in any of claims 1 to 3 Wherein, when the processing unit obtains the position information of the corner portion of the substrate with the front and back flipped, the processing unit performs an image in which one of the first image and the second image is mirror-converted and another The pattern matching of an image, and based on the result of the pattern matching, the position information of the corners of the substrate with the front and back flipped is obtained. The position detection device according to item 4 of the scope of patent application, wherein the first image and the second image are images of a region including the corner portion of the substrate in the interior. A position detection method in which a corner image of a substrate is captured from a first surface side of the substrate to obtain a first image, and the angle when viewed from the first surface side of the substrate is obtained based on the first image. Position information of the camera, the second image is obtained by photographing the corner portion of the substrate from the second surface side opposite to the first surface, based on the first image, the second image, and the basis The position information of the corner portions of the substrate obtained by the first image is obtained, and the position information of the corner portions when viewed from the second surface side of the substrate is obtained.