JP2024004563A - Alignment device, deposition device, and alignment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique to highly accurately detect an edge of a substrate in an alignment device that performs alignment of the substrate.

SOLUTION: An alignment device comprises: photographing means that photographs an edge image including an edge of a substrate 200 held by holding means 100; edge detection means that sets a detection area in the edge image and detects, from within the detection area, the edge of the substrate 200 along a reference direction of the detection area; and alignment means that, based on the edge detected by the edge detection means, performs alignment of the holding means 100 for the substrate 200. The edge detection means determines if a line segment along the reference direction detected from within the detection area is the edge of the substrate 200 based on the length in the reference direction of the detection area and the length of the line segment.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to an alignment device, a film forming apparatus including the alignment device, and an alignment method.

Organic EL display devices are known as flat panel display devices. An organic EL element that constitutes an organic EL display device has a basic structure in which a functional layer having a light-emitting layer, which is an organic layer that causes light emission, is formed between two opposing electrodes (a cathode electrode and an anode electrode). The functional layer and the electrode layer of an organic EL element are formed by depositing materials constituting each layer onto a substrate such as glass through a mask in a film deposition apparatus.

When a film forming apparatus performs film forming, an image obtained by photographing a substrate using an imaging device may be used for alignment, inspection, etc. of the substrate. Patent Document 1 discloses a configuration in which an edge image of a substrate held on a carrier is photographed using illumination light from a light source, and alignment of the substrate with respect to the carrier is performed based on positional information of the substrate obtained from the obtained edge image. Disclosed. In this configuration, the edge of the substrate is detected from the edge image in order to obtain position information of the substrate.

Japanese Patent Application Publication No. 2020-003469

However, if there is dirt or scratches on the substrate or a holding means such as a carrier that holds the substrate, the dirt or scratches may be mistakenly recognized as the edge of the substrate when detecting the edge of the substrate. Erroneous edge recognition may cause problems such as a decrease in alignment accuracy between the substrate and the holding means, and even damage to the substrate during substrate transportation.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a technique for detecting edges of a substrate with high precision in an alignment device that aligns the substrate with respect to a holding means.

The alignment device of the present invention includes:
An alignment device that aligns the substrate with respect to a holding means that holds the substrate, the alignment device comprising:
a photographing means for photographing an edge image including an edge of the substrate held by the holding means;
edge detection means for setting a detection area in the edge image and detecting an edge of the substrate along a reference direction of the detection area from within the detection area;
alignment means for aligning the substrate with respect to the holding means based on the edge detected by the edge detection means;
Equipped with
The edge detection means determines whether the line segment is an edge of the substrate based on the length of the detection area in the reference direction and the length of a line segment along the reference direction detected from within the detection area. It is characterized by determining whether
Furthermore, the alignment method of the present invention includes:
a photographing step of photographing an edge image including an edge of the substrate held by a holding means that holds the substrate;
a region setting step of setting a detection region within the edge image;
a line segment detection step of detecting a line segment along a reference direction of the detection area within the detection area;
a length obtaining step of obtaining the length of the line segment;
an edge detection step of detecting an edge of the substrate from the edge image based on the length of the line segment and the length of the detection area in the reference direction;
an alignment step of aligning the substrate with respect to the holding means based on the edge of the substrate detected in the edge detection step;
It is characterized by including.

According to the present invention, it is possible to provide a technique for detecting edges of a substrate with high precision in an alignment device that aligns the substrate with respect to a holding means.

FIG. 1 is a schematic configuration diagram of a film forming apparatus. FIG. 2 is a schematic configuration diagram of a substrate lifting device provided in a carrier delivery chamber. It is a figure which shows the photographed image and edge image of a board|substrate and a board|substrate carrier. FIG. 3 is a diagram illustrating a method for detecting edges of a substrate. FIG. 3 is a flow diagram of detecting edges of a substrate. FIG. 7 is a flowchart of detecting edges of a substrate according to a modified example. It is a schematic block diagram of a film-forming chamber. FIG. 2 is a diagram illustrating the configuration of an electronic device.

EMBODIMENT OF THE INVENTION Below, with reference to drawings, the form for implementing this invention is illustratively described in detail based on an Example. However, the dimensions, materials, shapes, and relative arrangement of the components described in this embodiment should be changed as appropriate depending on the configuration of the device to which the invention is applied and various conditions. That is, the scope of the present invention is not intended to be limited to the following embodiments.

The present invention is suitable for forming a thin film of a film-forming material on the surface of a film-forming object such as a substrate by vapor deposition or sputtering while transporting the film-forming object. The present invention can be understood as a substrate transport device, its control method, and a substrate transport method. The present invention can also be regarded as a film forming apparatus, a control method thereof, or a film forming method. The present invention can also be regarded as an electronic device manufacturing apparatus and an electronic device manufacturing method. The present invention can also be understood as a program that causes a computer to execute a control method, and a storage medium that stores the program. A storage medium may be a non-transitory computer readable storage medium.

The present invention can be applied, for example, to a film forming apparatus that forms a thin film of a film forming material on the surface of an object to be film-formed, such as a substrate, by vapor deposition or sputtering while conveying the film-forming object, such as a substrate, and forms a thin film with a desired pattern by vacuum evaporation. It can be desirably applied to an apparatus for forming (a material film). Any material such as glass, a film of a polymeric material, a silicon wafer, or metal can be selected as the material of the substrate, and the substrate may be, for example, a substrate in which a film of polyimide or the like is deposited on a glass substrate. . Furthermore, any material such as an organic material or a metallic material (metal, metal oxide, etc.) may be selected as the vapor deposition material. In addition to the vacuum deposition apparatus described in the following description, the present invention can also be applied to film forming apparatuses including sputtering apparatuses and CVD (Chemical Vapor Deposition) apparatuses. The technology of the present invention is
Specifically, it is applicable to manufacturing equipment for organic electronic devices (eg, organic light emitting elements, thin film solar cells), optical members, and the like. Among these, an organic light emitting device manufacturing apparatus that forms an organic light emitting device by evaporating a deposition material and depositing it on a substrate through a mask is one of the preferred application examples of the present invention. Hereinafter, the case where the present invention is applied to an electronic device manufacturing apparatus will be described as an example, but the alignment apparatus of the present invention is not limited to this, and can be applied to the various manufacturing apparatuses described above.

(Example)
<Film forming equipment>
FIG. 1 is a plan view showing a schematic configuration of a film forming apparatus including an alignment apparatus according to an embodiment of the present invention. Here, a film forming apparatus used in an organic EL display production line will be described. When manufacturing an organic EL display, a substrate of a predetermined size is carried into a film forming apparatus, and organic EL and metal layers are formed thereon. The substrate after film formation is carried out to a post-process and undergoes post-processing such as cutting the substrate.

In this embodiment, a film forming apparatus called an in-line type will be described as an example. In an in-line film forming apparatus, a plurality of chambers are arranged side by side, and the substrate 200, substrate carrier 100, and mask M are sequentially transported into each chamber, and various treatments are performed in each chamber. be done. To transport the substrate, etc., a transport roller or a linear motor is used as a transport means. A plurality of conveyance rollers are arranged along the conveyance direction on both sides of the conveyance path, and are rotated by the driving force of an AC servo motor (not shown) to convey the substrate carrier 100 and the mask M into and out of each room. do. Each chamber is configured so that a vacuum atmosphere or an inert gas atmosphere can be created for each chamber or for each of a plurality of adjacent chambers. In order to maintain the vacuum state inside the vacuum container, the film forming apparatus is equipped with a vacuum pump (not shown).

Note that the film forming apparatus to which the alignment apparatus of the present invention is applied is not limited to an in-line type, but may be a cluster type film forming apparatus. In a cluster type film forming apparatus, a film is formed on a substrate while being transported between a plurality of chambers arranged around a transport robot.

In FIG. 1, among the plurality of chambers, only the chamber that performs typical processing is shown with the symbol R, and the other chambers are omitted by black dots. Further, in FIG. 1, a thin solid line arrow indicates a transport route of the substrate carrier 100, a thin broken line arrow indicates a transport route of the substrate 200, and a thick solid line arrow indicates a transport route of the mask M. The operation of the devices provided in each room is controlled by a control unit C such as a computer. The control section C can be provided individually for each device, or a common control section C can be provided for a plurality of devices. Generally, it is a well-known technology that various operations are controlled by a control unit. As the control unit C, for example, an information processing device or a processing circuit equipped with calculation resources such as a processor and a memory can be used.

First, the substrate carrier 100 and the substrate 200 are sent to the substrate placement chamber R1, and the substrate 200 is held above the substrate carrier 100 in the substrate placement chamber R1. The substrate carrier 100, which serves as a holding means for holding the substrate 200, is arranged in the substrate mounting chamber R1 with the substrate holding surface facing upward in the vertical direction. The substrate 200 carried into the substrate mounting chamber R1 is placed on the substrate holding surface of the substrate carrier 100 so that the surface to be deposited faces upward in the vertical direction. During this placement, the film forming apparatus images the substrate 200 to obtain position information, and performs position adjustment (first alignment) so that the substrate 200 is at a predetermined position on the substrate carrier 100. The substrate carrier 100 and the substrate 200 held by the substrate carrier 100 are transported to the reversing chamber R2.

A reversing mechanism for reversing the orientation of the substrate holding surface of the substrate carrier 100 from vertically upward to vertically downward is disposed in the reversing chamber R2. In the reversing chamber R2, the substrate carrier 100 is rotated 180 degrees upside down together with the substrate 200 so that the substrate 200 is held below the substrate carrier 100.

Furthermore, the mask M is transported to the reversing chamber R2 from a route different from the transport route of the substrate carrier 100. In the reversing chamber R2, the substrate carrier 100 holding the substrate 200 on the lower side is placed on the mask M. The substrate 200 held by the substrate carrier 100 is then transported to the film forming chamber R3 together with the mask M sent to the reversing chamber R2. Note that the rotation of the substrate carrier 100, the joining with the mask M, and the mounting on the mask M may be performed in separate chambers.

An alignment device that aligns the substrate carrier 100 (and the substrate 200 held therein) and the mask M is arranged in the reversing chamber R2. The alignment device places the substrate carrier 100 on the mask M in a state where the substrate 200 and the mask M have a predetermined positional relationship in the in-plane direction of the film-forming surface of the substrate 200. When placing the substrate carrier 100 on the mask M in the reversing chamber R2, the film forming apparatus images the substrate 200 and the mask M to acquire positional information, and adjusts the position of the substrate 200 and the mask M in the in-plane direction. 2 alignment).

Subsequently, in the film forming chamber R3, a thin film is formed on the surface of the substrate 200 through a mask M having an opening at a desired film forming position, and then the substrate carrier 100 and the like are transported to the mask unloading chamber R4. Ru. Note that, generally, a plurality of film forming chambers R3 are provided as shown in FIG. 1 so that thin films can be formed using different materials. Therefore, normally, by transporting the substrate 200 once, a film forming process is performed in one specific film forming chamber R3.

After film formation, the substrate 200 held by the substrate carrier 100 is lifted from the mask M in the mask unloading chamber R4. The mask M that has been used a predetermined number of times is carried out from the mask carrying-out chamber R4 to the outside of the apparatus. The substrate 200 held by the substrate carrier 100 and the mask M to be used again are transported from the mask unloading room R4 to the relay room R5. The mask M in the relay room R5 is transported toward the reversal room R2. A mask stocker may be arranged on the production line to store a plurality of masks M and take them out as needed. The substrate carrier 100 and the substrate 200 in the relay room R5 are inverted in an inversion chamber (not shown) so that the film-forming surface of the substrate 200 and the substrate holding surface of the substrate carrier 100 face upward in the vertical direction, and then transferred to the substrate separation chamber. It is transported to R6.

Then, the substrate 200 is separated from the substrate carrier 100 in the substrate separation chamber R6. After that, the substrate carrier 100 is carried out to the outside of the film forming apparatus or transported to the substrate mounting chamber R1 again. Further, the substrate 200 peeled off from the substrate carrier 100 is taken out to the outside. Note that the present invention is not limited to the deposit-up configuration as shown in FIG. 1, but may also take a deposit-down configuration or a side deposit configuration.

<Operation of placing the board on the board carrier>
The operation of holding the substrate 200 on the substrate carrier 100 by the substrate lifting device disposed in the substrate mounting chamber R1 will be described with reference to FIGS. 2(a) and 2(b). FIG. 2A is a diagram showing how the substrate 200 carried into the carrier delivery chamber 300 is supported by the lifting mechanism 400. FIG. 2(b) is a diagram showing how the substrate 200 is held by the substrate carrier 100 in the carrier delivery chamber 300.

First, the schematic configuration of the substrate lifting device will be described. The substrate lifting device includes a carrier delivery chamber 300, a lifting mechanism 400, and a clamp rotation mechanism 500 as a clamp driving means. Note that a plurality of elevating mechanisms 400 having a similar configuration may be arranged in the substrate elevating device.

The carrier delivery chamber 300 includes an opening 321 through which the substrate 200 passes, and a substrate gate valve 322 that can open and close this opening 321. Further, although not shown in the drawings, the inside of the carrier delivery chamber 300 includes an opening through which the substrate carrier 100 passes, and a carrier gate valve that can open and close this opening. Through these openings, the substrate 200 and the substrate carrier 100 are carried into and out of the carrier delivery chamber 300 by a transport means such as a robot hand.

Further, the carrier delivery chamber 300 is provided with a carrier support member 330 that supports the substrate carrier 100 when the substrate 200 is placed on the substrate carrier 100. This carrier support member 330 supports the outer periphery of the substrate carrier 100 so as not to interfere with the operation of support pins provided in the elevating mechanism. Alternatively, the carrier support member 330 may be provided with an opening in a region through which the support pin passes. Moreover, a conveyance roller for conveying the substrate carrier 100 may be provided in the substrate mounting chamber R1 (carrier delivery chamber 300). In this case, when the substrate 200 is placed on the substrate carrier 100, the transport roller can support the substrate carrier 100.

Further, the carrier delivery room 300 is provided with an imaging means 350 (photographing means). Although only one imaging means 350 is shown in each figure, generally a plurality of imaging means 350 are provided. The control unit C can perform positional adjustment (alignment) of the substrate carrier 100 and the substrate 200 by acquiring position information from an image of the substrate carrier 100 and the substrate 200 taken by the imaging means 350. In the carrier delivery chamber 300, in order to perform alignment based on the edge image of the substrate 200, an imaging means 350 is arranged so that the viewing angle includes at least part of the sides and ends of the substrate 200.

Further, the imaging means 350 can also serve as a determining means for determining the type of substrate carrier 100 or the type of substrate 200. For example, various marks are attached depending on the type of the substrate carrier 100, and the type of the substrate carrier 100 can be determined based on the marks imaged by the imaging means 350. The imaging means 350 used for alignment and the imaging means 350 as a discrimination means may be provided separately, or one of the plurality of imaging means 350 generally provided for alignment may also be used as a discrimination means. You can also do it.

In this embodiment, only the support pin 411 of the lifting mechanism 400 is inserted into the carrier delivery chamber 300, and only the push pin 511 of the clamp rotation mechanism 500 is inserted into the carrier delivery chamber 300. There is. Thereby, lubricant, abrasion powder, and the like can be prevented from entering the carrier delivery chamber 300. Note that the entire substrate lifting device may be arranged in the substrate mounting chamber R1, or the carrier transfer chamber 300 described above may correspond to the substrate mounting chamber R1. In the latter case, most of the structure of the lifting mechanism (other than the support pin 411) and most of the structure of the clamp rotation mechanism 500 (other than the push-in pin 511) are arranged outside the substrate mounting chamber R1. will be done.

The elevating mechanism 400 includes a plurality of support pins 411, a first plate 410 that supports the plurality of support pins 411, and a ball screw mechanism 420 as a first elevating means for elevating the first plate 410. The plurality of support pins 411 serving as support means for supporting the substrate 200 are configured to be able to abut against the substrate 200 from below in the vertical direction, and as the support pins 411 move up and down within the carrier delivery chamber 300, the substrate 200 is supported. 200 goes up and down. Although a case is shown in which a ball screw mechanism is employed as the elevating means for elevating and lowering the first plate 410, other known techniques such as a rack and pinion system may also be employed as the elevating means.

The substrate lifting device also includes an alignment mechanism 430 as alignment means that adjusts the position of the substrate 200 with respect to the substrate carrier 100 by moving the plurality of support pins 411 in a direction perpendicular to the lifting direction of the substrate 200. Note that in this embodiment, the direction in which the substrate 200 is raised and lowered is the vertical direction. Therefore, the alignment mechanism 430 is configured to be able to move the plurality of support pins 411 in the horizontal direction. As for the movement mechanism of the support pin 411 in the alignment mechanism 430, various known techniques such as a ball screw mechanism or a rack and pinion type mechanism can be adopted.

With the alignment mechanism 430 configured as described above, the substrate 200 placed on the plurality of support pins 411 can be moved in the horizontal direction, and the position of the substrate 200 with respect to the substrate carrier 100 can be adjusted.

The clamp rotation mechanism 500 includes a plurality of push pins 511, a clamp plate 510 that supports the plurality of push pins 511, and a ball screw mechanism 520 that moves the clamp plate 510 up and down. The clamp rotation mechanism 500 is a mechanism that rotates the clamp 110 provided on the substrate carrier 100 to hold the substrate 200. A plurality of clamps 110 are provided on the substrate carrier 100, and the push pins 511 are provided at positions corresponding to the clamps 110. Although a case is shown in which a ball screw mechanism is employed as the elevating means for elevating and lowering the clamp plate 510, other known techniques such as a rack and pinion system may also be employed as the elevating means.

As mentioned above, the substrate carrier 100 includes a plurality of clamps 110 for holding the substrate 200. The clamp 110 is rotatably provided on the substrate carrier 100 in a state where it is biased by a biasing member in a first rotation direction, which is a direction in which the substrate 200 held by the substrate carrier 100 is clamped. Then, when placing the substrate 200 on the substrate carrier 100 and when peeling the substrate 200 from the substrate carrier 100, the clamp 110 is urged by the push pin 511 and rotates in the second rotation direction. In FIG. 2A, the clamp 110 on the left side is rotatably provided on the substrate carrier 100 in a state where it is biased clockwise, and the clamp 110 on the right side is in a state where it is biased counterclockwise. is rotatably provided on the substrate carrier 100.

Next, the movement of the substrate lifting device when holding the substrate 200 on the substrate carrier 100 in the carrier delivery chamber 300 will be described in detail. After the substrate 200 is carried into the carrier delivery chamber 300, it is supported by a plurality of support pins 411 at a position above the substrate carrier 100.

The image capturing means 350 captures an image of the substrate 200 while the substrate 200 is supported by the plurality of support pins 411 . Then, the control unit C acquires the positional information of the substrate 200 based on the image taken by the imaging means 350, and grasps the positional relationship between the substrate 200 and the substrate carrier 100.

Then, the control unit C moves the substrate 200 in the X-axis direction and the Y-axis direction by the alignment mechanism 430 in order to adjust the position of the substrate 200 with respect to the substrate carrier 100. As a result, the substrate 200 faces the substrate carrier 100 at a predetermined mounting position.

Thereafter, the support pins 411 are lowered by the lifting mechanism 400, and the tips of the plurality of support pins 411 move below the lower surface of the substrate carrier 100. During this process, the substrate 200 is placed on the substrate carrier 100. Note that the substrate carrier 100 is provided with a plurality of suction pads, and the substrate 200 is in a state of being suctioned by the plurality of suction pads. Note that simply placing the substrate 200 on the substrate carrier 100 may result in insufficient suction by the suction pad, so a step of pressing the substrate 200 downward to ensure more reliable suction by the suction pad is performed. It is also preferable to go through the process.

When the support pins 411 are lowered, the clamps 110 are pushed by the push pins 511 so that the substrate 200 can be placed on the substrate carrier 100. After the substrate 200 is placed on the substrate carrier 100, the clamping plate 510 is lowered by the clamp rotation mechanism 500. As a result, the push pin 511 separates from the clamp 110, and the clamp 110 rotates in the first rotation direction to sandwich the substrate 200 between the substrate carriers 100. Then, as shown in FIG. 2(b), the substrate 200 is held by the substrate carrier 100. The substrate 200 held as described above is taken out from the carrier delivery chamber 300 together with the substrate carrier 100 and transported to the reversing chamber R2.

<Alignment of board to board carrier>
The alignment and mounting of the substrate 200 on the substrate carrier 100 in the alignment device included in the film forming apparatus according to this embodiment will be described in more detail.

As described above, the control unit C acquires the positional information of the substrate 200 based on the image taken by the imaging means 350 in the substrate mounting chamber R1, and grasps the positional relationship with the substrate carrier 100. Then, the control unit C causes the alignment mechanism 430 to move the substrate 200 in the X-axis direction and the Y-axis direction. Thereby, the substrate 200 is placed at a predetermined placement position so as to face the substrate carrier 100, and then the substrate 200 is placed on the substrate carrier 100 by the elevating mechanism 400.

In this embodiment, as the imaging means 350, an optical imaging device is used in which the amount of illumination light from the light source, shutter speed, gain value, etc. can be controlled by the control unit C. The control unit C can adjust the obtained image by controlling at least one of the light amount, shutter speed, and gain value. Therefore, the control section C functions as a parameter adjustment means.

The control unit C of this embodiment analyzes the image taken by the imaging means 350, recognizes the edge of the substrate 200, and acquires position information of the substrate 200 based on the edge. With reference to FIGS. 3(a) to 3(d), a procedure for acquiring positional information of the board 200 from an image taken by the imaging means 350 will be described. FIG. 3(a) shows an image taken by the imaging means 350. FIG. 3(b) shows an edge image created by the control unit C based on the image taken by the imaging means 350. FIG. 3C shows how the edge of the substrate 200 is properly detected within the edge image. FIG. 3D shows, as a comparative example, how a scratch on the substrate carrier 100 is mistakenly recognized as an edge of the substrate 200 in the edge image.

The imaging means 350 of this embodiment targets one of the four corner edge portions of the substrate 200 having a substantially rectangular surface, and FIG. 3(a) shows the inside of the viewing angle 351. . In FIG. 3A showing an image taken by the imaging means 350, regions made of similar materials are shown in similar colors. That is, the inside of the substrate carrier 100 and the inside of the substrate 200 each have similar pixel values.

At the time of photographing in FIG. 3A, the substrate 200 is located above the substrate carrier 100 in the vertical direction, so when viewed from the imaging means 350 disposed above the substrate mounting chamber R1, a portion of the substrate carrier 100 is The substrate 200 is in an overlapping state. In the range of the viewing angle 351, the substrate 200 has an edge 210A parallel to the substrate transport direction and an edge 210B perpendicular to the substrate transport direction. Furthermore, in this example, the corners of the substrate 200 have a partially cut-out shape (corner edges 210C). Note that a carrier mark may be formed on a part of the substrate carrier 100. Further, FIG. 3A shows a photographed image when the substrate 200 is at a predetermined reference position when the substrate 200 is photographed by the imaging means 350. Here, the reference position is a designed target position. The reference position of the substrate 200 is set so that the edges 210A and 210B of the substrate 200 fall within the viewing angle 351 even if the position of the substrate 200 deviates from the reference position.

The control unit C performs image processing on the captured image to create an edge image. Existing edge extraction processing can be used to create an edge image; for example, an edge detection filter such as a differential filter can be applied to image data to create an edge image. In edge extraction, noise reduction processing such as smoothing may be performed as necessary. As in the edge image shown in FIG. 3(b), a portion that has a large change in pixel value from the pixel value of an adjacent pixel is extracted as an edge. In other words, the transition between the non-edge portion and the edge is detected based on the difference in contrast. As a result, the edges 210A, 210B and the corner edges 210C forming the outline of the substrate 200 are shown in an emphasized manner in the edge image, indicating transition portions between the edges and other portions.

When the edge of the substrate 200 is properly detected, the control unit C detects a first reference line 220A along the edge 210A and a second reference line along the edge 210B in the edge image, as shown in FIG. 3(c). A line 220B is obtained. The control unit C acquires position information in the in-plane direction of the substrate 200 from the first reference line 220A and the second reference line 220B that intersect with each other. Then, alignment of the substrate 200 with respect to the substrate carrier 100 is performed based on the position information. In this manner, in this embodiment, the positional information of the substrate is obtained from the positional information of the two edges of the substrate.

When creating an edge image, if the substrate 200 or the substrate carrier 100 has scratches or dirt, the scratches or dirt may be highlighted in the edge image in the same way as the edges of the substrate 200. In this case, scratches and dirt may be mistakenly recognized as edges during edge detection, which may affect alignment. For example, as in the comparative example shown in FIG. 3D, if the substrate carrier 100 has a scratch Sc, the first reference line 220A may be created along the scratch Sc instead of the edge 210A. In this way, if the first reference line 220A is created at an incorrect position due to the flaw Sc being erroneously recognized as an edge, alignment will be performed based on incorrect positional information of the substrate 200. If the alignment is not performed properly, the substrate 200 will not be placed in the correct position with respect to the substrate carrier 100, and various problems may occur, such as substrate cracking during transportation by the transportation means.

<Edge detection method>
In the present invention, in order to improve the edge detection accuracy of the substrate 200, a detection area is set within the edge image, and based on the length of the line within the detection area, it is determined whether the detected line segment is the edge of the substrate. We decided to make a judgment. Hereinafter, details of the edge detection method in an edge image according to the present invention will be described with reference to FIGS. 4(a) to 4(d), taking as an example a case where the substrate carrier 100 has a scratch Sc.

After creating an edge image, the control unit C serving as an edge detection means sets a rectangular first detection area T1 and a second detection area T2 within the edge image, as shown in FIG. 4(a). The first detection area T1 is an area for detecting the edge 210A, and the first detection area T1 is set so that the edge 210A is included in the area when the substrate 200 is located at the reference position. Similarly, the second detection region T2 is a region for detecting the edge 210B, and the second detection region T2 is set so that the edge 210B is included in the region. When the extending direction of the edge 210A when the substrate 200 is at the reference position is the first direction D1, and the extending direction of the edge 210B is the second direction D2, the first detection area T1 has a rectangular shape that is long in the second direction D2. , the sides of the first detection region T1 are parallel to the first direction D1 or the second direction D2. On the other hand, the second detection area T2 has a rectangular shape that is long in the first direction D1, and the sides of the second detection area T2 are parallel to the first direction D1 or the second direction D2. By setting the detection area in this manner, the desired edge is included in the detection area even if the substrate 200 is slightly displaced from the reference position at the time of photographing. Note that the shape and size of each detection area can be changed as appropriate depending on the substrate and substrate carrier. The edge detection method according to the present invention will be described below, taking as an example a case where a part of the scratch Sc is included in the first detection area T1.

After setting the detection area, the control unit C detects a line segment along the reference direction of the detection direction from within the detection area. Here, the reference direction of the detection area is set in a direction along the edge of the substrate 200 to be detected. Further, the line segment may be allowed to have some inclination with respect to the reference direction, and may be set not to be detected as a line segment if the angle between the reference direction and the line segment is greater than a predetermined value. In this embodiment, the control unit C divides the detection area in the detection direction and detects line segments within each divided area in order from the outer divided area of the substrate 200. As shown by arrows in FIG. 4(b), the detection direction in the first detection area T1 is parallel to the second direction D2, and the detection direction in the second detection area T2 is parallel to the first direction D1. That is, in the first detection region T1, first, a part of the scratch Sc on the outside of the substrate 200 is detected as the line segment L1a, instead of the edge 210A. On the other hand, in the second detection region T2, a part of the edge 210B is detected as a line segment L2a. Note that when detecting a line segment, even if there is a slight break in the middle, it may be treated as an unbroken point and detected as one line segment.

When a line segment is detected, the control unit C determines whether the detected line segment is an edge of the substrate 200 based on the length of the line segment. Specifically, the control unit C calculates the ratio of the length of the detected line segment to the length (width) of the detection area in the reference direction as the score value SV, and if the score value SV is equal to or greater than a predetermined value, Then, the line segment is detected as an edge of the substrate 200. In this embodiment, a line segment is detected as an edge of the substrate 200 when the score value is 80% or more. That is, in each of the first detection region T1 and the second detection region T2, the threshold value of the score value for detecting a line segment as an edge of the substrate 200 is 80%. In this example, the same threshold value is set for the first detection area T1 and the second detection area T2, but the first threshold value for the first detection area T1 is set to 90%, and the first threshold value for the second detection area T2 is set to 90%. Different threshold values may be set for each detection area, such as setting the threshold value of 2 to 80%.

As shown in FIG. 2(b), in the first detection region T1, the length Q1 of the first detection region T1 in the first direction D1 is used in calculating the score value SV. By using the width in a direction approximately parallel to the direction in which the edge 210A of the substrate 200 extends for calculating the score value SV, the threshold value of the score value SV can be set high, thereby reducing erroneous recognition of edges. When the control unit C detects a part of the scratch Sc as a line segment L1a, the control unit C calculates the score value SV1a= from the length Q1 of the first detection area T1 in the first direction D1 and the length P1a of the line segment L1a in the first direction D1. Calculate P1a/Q1 [%]. Here, if the score value SV1a is less than the threshold value, the control unit C determines that the line segment L1a is not an edge of the substrate 200, and starts detecting a new line segment along the detection direction. In this embodiment, the score value SV1a is 50%, and the control unit C determines that the line segment L1a is not an edge of the substrate 200.

When detection of a new line segment is started in the first detection area T1, a part of the edge 210A is then detected as a line segment L1b, as shown in FIG. 4(c). Then, the score value SV1b=P1b/Q1 [%] is calculated from the length Q1 of the first detection region T1 in the first direction D1 and the length P1b of the line segment L1b in the first direction D1. Since the edge 210A extends across the first detection region T1, the score value SV1b is calculated as 100%. Then, the control unit C detects the line segment L1b as an edge of the substrate 200, assuming that the score value SV1b is equal to or greater than the threshold value of 80%. In addition, if the length of the detected line segment is longer than the length of the detection area in the reference direction and the score value is 100% or more, that line segment is detected as an edge, and subsequent line segment detection and judgment are performed. It is also possible not to do it.

In the second detection area T2, the length Q2 of the second detection area T2 in the second direction D2 is used in calculating the score value. In the second detection area T2, there are no scratches or stains, and a part of the edge 210B is first detected as a line segment L2a. Then, the score value SV2a=P2a/Q2 [%] is calculated from the length Q2 of the second detection region T2 in the second direction D2 and the length P2a of the line segment L2a in the second direction D2. Since the edge 210A extends across the first detection region T1, the score value SV1b is calculated as 100%. Then, the control unit C detects the line segment L2a as an edge of the substrate 200, assuming that the score value SV2a is equal to or greater than the threshold value of 80%.

Based on the edges detected in each detection area through the above steps, the control unit C uses a first reference line 220A along the edge 210A as position information of the substrate 200, as shown in FIG. 4(d). A second reference line 220B along the edge 210B is obtained. That is, since the positional information of two sides of the surface of the substrate 200 is obtained, the positional information of the substrate 200 in the in-plane direction of the substrate 200 can be obtained.

Note that in this embodiment, it was determined whether a line segment is an edge based on the length of the line segment detected within the detection area, but in addition to the length of the line segment, the angle of the line segment The determination may also be made based on the size and thickness. By increasing the edge determination criteria in this way, more accurate edge detection becomes possible.

<Edge detection processing flow>
Referring to FIG. 5, the edge detection flow for the substrate 200 of this embodiment will be described. When the substrate 200 is carried into the substrate mounting chamber R1, the substrate 200 is placed above the substrate carrier 100 so that the edge of the substrate 200 is roughly included in the viewing angle 351 of the imaging means 350. At this time, the substrate 200 is placed at the reference position, but some deviation from the reference position is allowed. Then, as a photographing step, after the image capturing means 350 photographs an edge image of the board, the control unit C starts edge detection within the edge image (S100).

First, in the region setting step of step S101, a first detection region T1 and a second detection region T2 are set. At this time, a part of the edge 210A (first side) of the substrate 200 located approximately at the reference position is included in the first detection area T1, and a part of the edge 210B (second side) is included in the second detection area T2. included.

In the line segment detection step of step S102, the control unit C detects line segments from the edge image. As described above, in this embodiment, the detection direction is set from the outside to the inside of the substrate 200. Therefore, if a flaw on the substrate carrier 100 is included in the edge image, the flaw on the substrate carrier 100 is detected as a line segment before the edge of the substrate 200.

In the length acquisition step of step S103, the length of the line segment detected in step S102 is acquired. Then, in the score value calculation step of step S104, a score value of each line segment is obtained based on the length of the line segment obtained in step S103. In the first detection area T1, a first ratio of the length of the first line segment to the length Q1 of the first detection area T1 in the first direction D1 is calculated as a score value. In the second detection area T2, a second ratio of the length of the second line segment to the length Q2 of the second detection area T2 in the second direction D2 is calculated as a score value.

In the determination step of step S105, it is determined whether the score value acquired in step S104 exceeds a threshold value. Here, if it is determined that the score value does not exceed the threshold (S
105: NO), it is determined that the line segment detected in step S102 is not an edge of the substrate 200, and the process proceeds to a line segment detection step of step S106, where detection of a new line segment is started along the detection direction. Then, when a new line segment is detected in step S102, the steps from step S103 to step S105 are repeated again. Note that if a new line segment cannot be detected in step S106, a configuration may be adopted in which an error is notified to the user.

If it is determined in step S105 that the score value of the line segment exceeds the threshold (YES in S105), in the edge detection step of step S107, the edge of the substrate 200 is detected based on the determination result in step S105. . When an edge of the substrate 200 is detected in each detection area, edge detection ends (S108). Then, as an alignment step, the substrate 200 is aligned with the substrate carrier 100 based on the positional information of the substrate 200 obtained from the detected edges.

As described above, according to this embodiment, even if the substrate carrier 100 has scratches or dirt, it is possible to reduce the possibility of erroneously recognizing the scratches or dirt as edges of the substrate 200, and to raise the edge of the substrate 200. Can be detected accurately. As a result, problems such as a decrease in alignment accuracy and damage to the substrate can be suppressed.

Note that the configuration of the present invention is not limited to the above-described configuration, and various changes can be made without losing the sameness as the invention embodied in the above-described embodiments. For example, in the above embodiment, the present invention was applied to edge detection when aligning the substrate to the substrate carrier in the substrate mounting chamber, but the present invention was applied when aligning the substrate in other chambers. May be applied. In addition, in the above embodiment, the score value used for edge detection of the board was the ratio of the length of the line segment to the length of the detection area, but the length of the line segment itself or the length of the line segment The difference between the detection area and the length of the detection area may be used as the score value.

Further, in the edge detection flow shown in FIG. 5, determination is made by comparing the score value of a line segment with a threshold value, but the present invention is not necessarily limited thereto. For example, a determination flow may be used in which line segments detected within the detection area are compared and the line segment with the highest score value is detected as an edge. Referring to FIG. 6, a method will be described as a modification of the above-described embodiment in which line segments detected within the detection area are compared and the line segment with the highest score value is detected as an edge.

When edge detection is started (S200), 0 is first substituted into [maximum score value] in step S201. The method from step S202 to step S205 of setting a detection area, detecting a line segment from within the detection area, and obtaining a line segment score value is similar to the edge detection flow shown in FIG. be.

In the determination steps S206, 208, and 209, various determinations are made regarding the score value acquired in step S204. First, in step S206, it is determined whether the score value is 100 or more. Here, if it is determined that the score value is 100 or more (YES in S206), the process advances to step S207, where a line segment with a score value of 100 or more is determined as an edge of the substrate 200, and edge detection ends ( S214).

On the other hand, if it is determined in step S206 that the score value is less than 100 (NO in S206), the process proceeds to step S208, and it is determined whether the score value is greater than or equal to the threshold value. Here, if the score value is greater than or equal to the threshold (YES in S208), the process advances to step S209, and it is determined whether the score value is greater than [maximum score value]. If the score value is greater than the [maximum score value] (YES in S209), the score value is substituted into the [maximum score value] in step S210. Then, in step S211, it is determined whether detection of all line segments within the detection area has been completed. Note that if the score value is determined to be less than the threshold in step S208 (NO in S208) or if the score value is determined to be less than the [maximum score value] in step S209 (No in S209), The process proceeds to step S211 without assigning a new numerical value to the score value]. Further, each determination process is not limited to being performed in the above order, and the order of steps S208 and S209 may be exchanged, and step S208 is performed most after all line segment detection is completed. It may also be performed only for high score values.

If it is determined in step S211 that detection of all line segments has not been completed (NO in S211), the process advances to step S212, a line segment detection step, and detection of a new line segment is started along the detection direction. be done. Then, when a new line segment is detected in step S203, the steps from step S204 to step S211 are repeated again.

If it is determined in step S211 that line segment detection has been completed (YES in S211), in the edge detection process of step S213, the line segment having the [maximum score value] from among the line segments detected so far is 200 edges are detected. When an edge of the substrate 200 is detected in each detection area, edge detection ends (S214). Then, as an alignment step, the substrate 200 is aligned with the substrate carrier 100 based on the positional information of the substrate 200 obtained from the detected edges. Note that if no line segment can be detected within the detection area or if a line segment with a score value greater than or equal to a threshold value cannot be detected, an error may be notified to the user. As described above, by increasing the criteria for determining a line segment with a score value of 100 or more or the longest line segment among the detected line segments to be an edge of the board, edges of the board can be detected with higher accuracy. can do.

<Film forming chamber>
With reference to FIG. 7, the film forming process in the film forming chamber R3 will be described in more detail. An evaporation source 600 as a film forming source is provided in the film forming chamber R3. The substrate 200 held by the substrate carrier 100 is positioned and supported within the film forming chamber R3 so that it faces downward. Further, a mask M is also arranged below the substrate 200 in a state in which it is positioned with respect to the substrate 200. The mask M is provided with an opening at a position corresponding to a position where a thin film is to be formed on the substrate 200. Thereby, film formation is performed on the substrate 200 held by the substrate carrier 100 via the mask M.

In this embodiment, film formation (vapor deposition) is performed by vacuum evaporation. Specifically, the film-forming material is evaporated or sublimated from the evaporation source 600, and the film-forming material is vapor-deposited onto the substrate 200 to form a thin film on the substrate 200. Since the evaporation source 600 is a known technique, detailed explanation thereof will be omitted. For example, the evaporation source 600 can be configured with a container such as a crucible that contains a film forming material, a heating device that heats the container, and the like. Note that the film forming source is not limited to the evaporation source 600, and may be a sputtering cathode for forming a film by sputtering.

<Method for manufacturing electronic devices>
Next, an example of a method for manufacturing an electronic device using the film forming apparatus according to this embodiment will be described. Hereinafter, the configuration of an organic EL display device will be shown as an example of an electronic device, and a method for manufacturing the organic EL display device will be illustrated.

First, the organic EL display device to be manufactured will be explained. FIG. 8(a) shows an overall view of the organic EL display device 700, and FIG. 8(b) shows a cross-sectional structure of one pixel.

As shown in FIG. 8A, in the display area 701 of the organic EL display device 700, a plurality of pixels 702 each including a plurality of light emitting elements are arranged in a matrix. Although details will be explained later, each light emitting element has a structure including an organic layer sandwiched between a pair of electrodes. Note that the pixel herein refers to the smallest unit that can display a desired color in the display area 701. In the case of the organic EL display device according to this embodiment, a pixel 702 is configured by a combination of a first light emitting element 702R, a second light emitting element 702G, and a third light emitting element 702B that emit light different from each other. The pixel 702 is often composed of a combination of a red light-emitting element, a green light-emitting element, and a blue light-emitting element, but it may also be a combination of a yellow light-emitting element, a cyan light-emitting element, and a white light-emitting element. There are no restrictions.

FIG. 8(b) is a schematic partial cross-sectional view taken along line BB in FIG. 8(a). The pixel 702 consists of a plurality of light emitting elements, and each light emitting element has a first electrode (anode) 704, a hole transport layer 705, one of the light emitting layers 706R, 706G, and 706B, and an electron transport layer on a substrate 703. It has a layer 707 and a second electrode (cathode) 708. Among these, the hole transport layer 705, the light emitting layers 706R, 706G, and 706B, and the electron transport layer 707 correspond to organic layers. Further, in this embodiment, the light-emitting layer 706R is an organic EL layer that emits red, the light-emitting layer 706G is an organic EL layer that emits green, and the light-emitting layer 706B is an organic EL layer that emits blue. The light-emitting layers 706R, 706G, and 706B are formed in patterns corresponding to light-emitting elements (sometimes referred to as organic EL elements) that emit red, green, and blue, respectively.

Further, the first electrode 704 is formed separately for each light emitting element. The hole transport layer 705, the electron transport layer 707, and the second electrode 708 may be formed in common for the plurality of light emitting elements 702R, 702G, and 702B, or may be formed for each light emitting element. Note that an insulating layer 709 is provided between the first electrodes 704 in order to prevent the first electrodes 704 and the second electrodes 708 from shorting due to foreign matter. Furthermore, since the organic EL layer is degraded by moisture and oxygen, a protective layer 710 is provided to protect the organic EL element from moisture and oxygen.

In FIG. 8(b), the hole transport layer 705 and the electron transport layer 707 are shown as one layer, but depending on the structure of the organic EL display element, they may be formed as multiple layers including a hole blocking layer and an electron blocking layer. may be formed. Further, between the first electrode 704 and the hole transport layer 705, a positive hole having an energy band structure that allows holes to be smoothly injected from the first electrode 704 to the hole transport layer 705 is provided. A hole injection layer can also be formed. Similarly, an electron injection layer can also be formed between the second electrode 708 and the electron transport layer 707.

Next, an example of a method for manufacturing an organic EL display device will be specifically described.

First, a substrate (mother glass) 703 on which a circuit (not shown) for driving an organic EL display device and a first electrode 704 are formed is prepared.

Acrylic resin is formed by spin coating on the substrate 703 on which the first electrode 704 is formed, and the acrylic resin is patterned by lithography so that an opening is formed in the part where the first electrode 704 is formed, and an insulating layer is formed. Form 709. This opening corresponds to the light emitting region where the light emitting element actually emits light.

A substrate 703 on which an insulating layer 709 has been patterned is placed on a substrate carrier on which an adhesive member is arranged. The substrate 703 is held by the adhesive member. After being carried into a first organic material film forming apparatus and inverted, a hole transport layer 705 is formed as a common layer on the first electrode 704 in the display area. The hole transport layer 705 is formed by vacuum deposition. In reality, the hole transport layer 705 is formed to have a larger size than the display area 701, so a high-definition mask is not required.

Next, the substrate 703 on which up to the hole transport layer 705 has been formed is carried into a second organic material film forming apparatus. The substrate and the mask are aligned, the substrate is placed on the mask, and a light-emitting layer 706R that emits red light is formed on a portion of the substrate 703 where an element that emits red light is to be arranged.

Similar to the formation of the light-emitting layer 706R, a light-emitting layer 706G that emits green light is formed by a third organic material film-forming device, and a light-emitting layer 706B that emits blue light is further formed by a fourth organic material film-forming device. . After the formation of the light emitting layers 706R, 706G, and 706B is completed, the electron transport layer 707 is formed over the entire display area 701 using a fifth film formation apparatus. The electron transport layer 707 is formed as a layer common to the three color light emitting layers 706R, 706G, and 706B.

A second electrode 708 is formed by moving the substrate on which the electron transport layer 707 has been formed using a metal vapor deposition material film forming apparatus.

Thereafter, the film is moved to a plasma CVD apparatus, a protective layer 710 is formed, and the film forming process on the substrate 703 is completed. After inversion, the adhesive member is peeled off from the substrate 703 to separate the substrate 703 from the substrate carrier. Thereafter, the organic EL display device 700 is completed through cutting.

If the substrate 703 on which the insulating layer 709 has been patterned is exposed to an atmosphere containing moisture or oxygen from the time the substrate 703 on which the insulating layer 709 has been patterned is carried into the film forming apparatus until the film forming of the protective layer 710 is completed, the light emitting layer made of the organic EL material may There is a risk of deterioration due to moisture and oxygen. Therefore, in this embodiment, substrates are carried in and out between film forming apparatuses under a vacuum atmosphere or an inert gas atmosphere.

DESCRIPTION OF SYMBOLS 100...Carrier (holding means), 200...Substrate, 220A...Intersection (first reference point), 220B...Intersection (second reference point), 350...Imaging means (photographing means), 411...Support pin (supporting means) ), C...Control unit (judgment means), L1...Distance

Claims (15)

An alignment device that aligns the substrate with respect to a holding means that holds the substrate, the alignment device comprising:
a photographing means for photographing an edge image including an edge of the substrate held by the holding means;
edge detection means for setting a detection area in the edge image and detecting an edge of the substrate along a reference direction of the detection area from within the detection area;
alignment means for aligning the substrate with respect to the holding means based on the edge detected by the edge detection means;
Equipped with
The edge detection means determines whether the line segment is an edge of the substrate based on the length of the detection area in the reference direction and the length of a line segment along the reference direction detected from within the detection area. An alignment device characterized by determining whether The substrate has a substantially rectangular surface,
The alignment apparatus according to claim 1, wherein the reference direction is a direction parallel to a side of the substrate when the substrate is at a predetermined reference position. The alignment device according to claim 1, wherein the detection area has a rectangular shape with sides parallel to the reference direction. The edge detection means calculates a ratio of the length of the line segment to the length of the detection area in the reference direction, and if the ratio is greater than or equal to a predetermined value, the line segment is an edge of the substrate. The alignment device according to claim 1, wherein the alignment device determines that 2. The edge detection means determines that the line segment is an edge of the substrate when the length of the line segment is equal to or longer than the length of the detection area in the reference direction. 1. The alignment device according to 1. 2. The alignment apparatus according to claim 1, wherein the edge detection means determines that the longest line segment among the line segments detected within the detection area is the edge of the substrate. The photographing means includes a first side of the substrate extending in a first direction and a second side extending in a second direction different from the first direction in the edge image when the substrate is at a predetermined reference position. Take pictures to include
The alignment according to claim 1, wherein the edge detection means sets a first detection area including the first side and a second detection area including the second side as the detection area. Device. The first detection area has a rectangular shape that is long in the second direction,
8. The alignment device according to claim 7, wherein the second detection area has a rectangular shape that is elongated in the first direction. The edge image has a rectangular shape long in the first direction,
8. The alignment device according to claim 7, wherein the length of the first detection area in the first direction is longer than the length of the second detection area in the second direction. The edge detection means includes:
A first ratio of a length of a first line segment in the first detection area to a length of the first detection area in the first direction is calculated, and the first ratio is equal to or greater than a first threshold value. If there is, the first line segment is determined to be an edge of the substrate,
A second ratio of a length of a second line segment in the second detection area to a length of the second detection area in the second direction is calculated, and the second ratio is greater than or equal to a second threshold. 8. The alignment apparatus according to claim 7, wherein if there is an edge of the substrate, the second line segment is determined to be an edge of the substrate. The alignment apparatus according to claim 1, wherein the edge detection means detects the line segment from the detection area based on the contrast of the edge image. 2. The alignment apparatus according to claim 1, wherein the edge detection means determines whether the line segment is the edge based on the angle of the line segment in addition to the length of the line segment. The alignment apparatus according to claim 1, wherein the edge detection means determines whether the line segment is the edge based on the thickness of the line segment in addition to the length of the line segment. . The alignment device according to any one of claims 1 to 13,
a film-forming source that releases a film-forming material toward the substrate held by the holding means;
A film forming apparatus comprising: a photographing step of photographing an edge image including an edge of the substrate held by a holding means that holds the substrate;
a region setting step of setting a detection region within the edge image;
a line segment detection step of detecting a line segment along a reference direction of the detection area within the detection area;
a length obtaining step of obtaining the length of the line segment;
an edge detection step of detecting an edge of the substrate from the edge image based on the length of the line segment and the length of the detection area in the reference direction;
an alignment step of aligning the substrate with respect to the holding means based on the edge of the substrate detected in the edge detection step;
An alignment method comprising:

Images