Alignment device, film forming apparatus and alignment method

Abstract

An alignment device is characterized by being provided with: an image capturing means for capturing an edge image including an edge of a substrate (200) held by a holding means (100); an edge detection means for setting a detection region in the edge image, and detecting the edge of the substrate (200) along the reference direction of the detection region from within the detection region; and an alignment means for aligning the substrate (200) with respect to the holding means (100) on the basis of the edge detected by the edge detection means, the edge detection means determining whether or not a line segment is the edge of the substrate (200) on the basis of the length of the detection region in the reference direction and the length of the line segment detected from within the detection region along the reference direction.

Description

Technical Field

[0001] The present invention relates to an alignment device, a film forming device having the alignment device, and an alignment method. Background Art

[0002] As a flat panel display device, an organic EL display device is known. An organic EL element constituting an organic EL display device has a basic structure in which a functional layer is formed between two electrodes (a cathode electrode and an anode electrode) facing each other, and the functional layer has a light-emitting layer as an organic material layer that causes light emission. The functional layer and electrode layer of the organic EL element are formed by forming a film of the material constituting each layer on a substrate such as glass through a mask in a film forming device.

[0003] When a film forming device is performing film forming, an image obtained by photographing a substrate using an imaging device is sometimes used for alignment or inspection of the substrate. Patent document 1 discloses a structure in which an edge image of a substrate held on a carrier is photographed using illumination light from a light source, and the substrate is aligned with respect to the carrier based on position information of the substrate obtained from the obtained edge image. In this structure, in order to obtain position information of the substrate, the edge of the substrate is detected from the edge image.

[0004] Prior Art Literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2020-003469 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, if there are stains or scratches on the substrate or on the holding components such as the carrier that holds the substrate, the stains or scratches may be mistakenly identified as the edge of the substrate during the edge detection of the substrate. Misidentification of the edge may cause the alignment accuracy between the substrate and the holding component to decrease, and further cause the substrate to be damaged during the transfer of the substrate.

[0009] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a technology for detecting an edge of a substrate with high accuracy in an alignment device for aligning a substrate with respect to a holding member.

[0010] Solutions to Solve Problems

[0011] The alignment device of the present invention performs alignment of a substrate relative to a holding member holding the substrate, and is characterized in that:

[0012] The alignment device comprises:

[0013] a photographing member for photographing an edge image including an edge of the substrate held by the holding member;

[0014] an edge detection unit that sets a detection area in the edge image and detects an edge of the substrate along a reference direction of the detection area from within the detection area; and

[0015] an alignment component, which aligns the substrate relative to the holding component based on the edge detected by the edge detection component,

[0016] The edge detection unit 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 the line segment detected from within the detection area along the reference direction.

[0017] Furthermore, the alignment method of the present invention is characterized in that

[0018] The alignment method comprises:

[0019] a photographing step of photographing an edge image including an edge of the substrate held by a holding member for holding the substrate;

[0020] A region setting step of setting a detection region in the edge image;

[0021] A line segment detection step of detecting, within the detection area, line segments along a reference direction of the detection area;

[0022] A length obtaining step of obtaining the length of the line segment;

[0023] an edge detection step of detecting an edge of the substrate from the edge image according to the length of the line segment and the length of the reference direction of the detection area; and

[0024] The alignment step aligns the substrate with respect to the holding member based on the edge of the substrate detected in the edge detection step.

[0025] Effects of the Invention

[0026] According to the present invention, it is possible to provide a technique for detecting an edge of a substrate with high accuracy in an alignment device that aligns a substrate with respect to a holding member. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of a film forming device.

[0028] Figure 2 This is a schematic structural diagram of a substrate lifting device installed in a carrier transfer chamber.

[0029] Figure 3 The figures show the captured images and edge images of the substrate and substrate carrier.

[0030] Figure 4 It is a diagram showing a method of detecting an edge of a substrate.

[0031] Figure 5 It is a flow chart of edge detection of substrate.

[0032] Figure 6 This is a flowchart of edge detection of a substrate according to a modified example.

[0033] Figure 7 This is a schematic structural diagram of the film forming chamber.

[0034] Figure 8 A diagram illustrating the structure of an electronic device. DETAILED DESCRIPTION

[0035] Hereinafter, with reference to the accompanying drawings, the mode for implementing the present invention is described in detail by way of example based on the embodiments. However, the size, material, shape and relative arrangement of the components described in the present embodiment should be appropriately changed according to the structure and various conditions of the device to which the invention is applied. That is, the scope of the present invention is not limited to the following embodiments.

[0036] The present invention is preferably applied to forming a thin film of film-forming material on the surface of a film-forming object such as a substrate by evaporation or sputtering while conveying the substrate. The present invention can be understood as a substrate conveying device and a control method thereof, and a substrate conveying method. The present invention can also be understood as a film-forming device and a control method thereof or a film-forming method. The present invention can also be understood as an electronic device manufacturing device or an electronic device manufacturing method. The present invention can also be understood as a program that enables a computer to execute a control method or a storage medium storing the program. The storage medium can also be a non-temporary storage medium that can be read by a computer.

[0037] The present invention can be applied to, for example, a film forming device that forms a thin film of a film forming material on its surface by evaporation or sputtering while conveying a film forming object such as a substrate, and can be preferably applied to a device that forms a thin film (material film) of a desired pattern by vacuum evaporation. As the material of the substrate, any material such as glass, a film of a polymer material, a silicon wafer, a metal, etc. can be selected. For example, the substrate can also be a substrate on which a film such as polyimide is deposited on a glass substrate. In addition, as the evaporation material, any material such as an organic material, a metal material (metal, metal oxide, etc.) can also be selected. In addition, in addition to the vacuum evaporation device described in the following description, the present invention can also be applied to a film forming device including a sputtering device or a CVD (Chemical Vapor Deposition: Chemical Vapor Deposition) device. Specifically, the technology of the present invention can be applied to manufacturing devices for organic electronic devices (such as organic light-emitting elements, thin-film solar cells), optical components, etc. Among them, a manufacturing device for an organic light-emitting element that forms an organic light-emitting element by evaporating the evaporation material and evaporating it onto a substrate through a mask is one of the preferred application examples of the present invention. Hereinafter, a 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 thereto and can be applied to the various manufacturing apparatuses described above. Example

[0038] <Film forming device>

[0039] Figure 1 This is a top view showing a schematic structure of a film forming device including an alignment device according to an embodiment of the present invention. Here, a film forming device on a manufacturing line of an organic EL display is described. When manufacturing an organic EL display, a substrate of a specified size is loaded into the film forming device to form an organic EL or metal layer. The substrate after film formation is loaded to a post-process and subjected to post-processing such as substrate cutting.

[0040] In this embodiment, a film forming apparatus called an in-line type is used as an example for explanation. In an in-line film forming apparatus, a plurality of chambers (cavities) are arranged in an array, and a substrate 200, a substrate carrier 100, and a mask M are sequentially transported to each chamber, and various processes are performed in each chamber. In the transport of the substrate, etc., a transport roller or a linear motor is used as a transport component. A plurality of transport rollers are arranged along the transport direction on both sides of the transport path, and the substrate carrier 100 and the mask M are transported to the inside and outside of each chamber by rotating them respectively using the driving force of an AC servo motor not shown in the figure. In each chamber, a vacuum atmosphere or an inert gas atmosphere is formed according to each chamber or a plurality of adjacent chambers. In order to maintain the vacuum state inside the vacuum container, the film forming apparatus is provided with a vacuum pump not shown in the figure.

[0041] Furthermore, the film forming apparatus to which the alignment device of the present invention is applied is not limited to an inline type, but may be a cluster type film forming apparatus. In a cluster type film forming apparatus, a film is formed while a substrate is transferred between a plurality of chambers arranged around a transfer robot.

[0042] exist Figure 1 In the figure, only the chambers that perform representative processing among the multiple chambers are marked with reference numerals R and are shown in the figure, and the other chambers are omitted using black dots. Figure 1 In the figure, the thin solid arrow indicates the conveying path of the substrate carrier 100, the thin dotted arrow indicates the conveying path of the substrate 200, and the thick solid arrow indicates the conveying path of the mask M. The actions of the devices in each chamber are controlled by a control unit C such as a computer. The control unit C can be set for each device individually or a common control unit C can be set for multiple devices. Generally speaking, it is a well-known technology that the control unit controls various actions. As the control unit C, for example, an information processing device or a processing circuit having computing resources such as a processor or a memory can be used.

[0043] First, the substrate carrier 100 and the substrate 200 are sent to the substrate loading chamber R1, and in the substrate loading chamber R1, the substrate 200 is held on the upper side of the substrate carrier 100. The substrate carrier 100, which is a holding component for holding the substrate 200, is arranged in the substrate loading chamber R1 with the substrate holding surface facing upward in the vertical direction. The substrate 200 transported into the substrate loading chamber R1 is placed on the substrate holding surface of the substrate carrier 100 with the film-forming surface facing upward in the vertical direction. During this placement, the film-forming device photographs the substrate 200 to obtain position information, and performs position adjustment (first alignment) so that the substrate 200 reaches a predetermined position on the substrate carrier 100. The substrate carrier 100 and the substrate 200 held on the substrate carrier 100 are transported to the reversing chamber R2.

[0044] The reversing chamber R2 is provided with a reversing mechanism for reversing the substrate holding surface of the substrate carrier 100 from vertically upward to vertically downward. 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 at the lower side of the substrate carrier 100.

[0045] Furthermore, the mask M is transported to the reversing chamber R2 from a path different from the transport path of the substrate carrier 100. In the reversing chamber R2, the substrate carrier 100 holding the substrate 200 at the lower side is placed on the mask M. Then, the substrate 200 held on the substrate carrier 100 is transported to the film forming chamber R3 together with the mask M transported to the reversing chamber R2. In addition, the rotation of the substrate carrier 100, the merging with the mask M, and the placement on the mask M may be performed in different chambers.

[0046] An alignment device for aligning the substrate carrier 100 (and the substrate 200 held thereon) with the mask M is disposed 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 are in a predetermined positional relationship in the in-plane direction of the film-forming surface of the substrate 200. When the substrate carrier 100 is placed on the mask M in the reversing chamber R2, the film forming device captures the substrate 200 and the mask M, obtains position information, and performs position adjustment of the substrate 200 and the mask M in the in-plane direction (second alignment).

[0047] Next, in the film forming chamber R3, after a thin film is formed on the surface of the substrate 200 via the mask M having openings at the desired film forming position, the substrate carrier 100 and the like are transported to the mask unloading chamber R4. Figure 1 As shown, a plurality of film forming chambers R3 are generally provided so that thin films can be formed from different materials. Therefore, a film forming process is usually performed in a specific film forming chamber R3 by conveying the substrate 200 once.

[0048] After film formation, in the mask unloading chamber R4, the substrate 200 held on the substrate carrier 100 is lifted from the mask M. The mask M that has been used a predetermined number of times is unloaded from the mask unloading chamber R4 to the outside of the device. The substrate 200 held on the substrate carrier 100 and the mask M to be used again are transported from the mask unloading chamber R4 to the relay chamber R5. The mask M in the relay chamber R5 is transported toward the reversing chamber R2. A mask storage device that stores a plurality of masks M and is carried out as needed may also be arranged on the manufacturing line. The substrate carrier 100 and the substrate 200 in the relay chamber R5 are turned over in a reversing chamber (not shown) so that the film-forming surface of the substrate 200 and the substrate holding surface of the substrate carrier 100 are vertically facing upward, and then transported to the substrate stripping chamber R6.

[0049] Then, in the substrate peeling chamber R6, the substrate 200 is peeled off from the substrate carrier 100. Then, the substrate carrier 100 is carried out to the outside of the film forming apparatus, or is again carried to the substrate loading chamber R1. In addition, the substrate 200 peeled off from the substrate carrier 100 is taken out to the outside. In addition, the present invention is not limited to Figure 1 Such an upward deposition structure may also adopt a downward deposition structure or a side deposition structure.

[0050] <Substrate Loading Operation on Substrate Support>

[0051] Reference Figure 2 (a) and (b) illustrate the operation of holding the substrate 200 on the substrate carrier 100 by the substrate lifting and lowering device disposed in the substrate loading chamber R1. Figure 2 (a) is a diagram showing a state in which the substrate 200 carried into the carrier delivery chamber 300 is supported by the lifting mechanism 400 . Figure 2 (b) is a diagram showing a state in which the substrate 200 is held by the substrate carrier 100 in the carrier delivery chamber 300 .

[0052] First, the schematic structure of the substrate lifting device is described. The substrate lifting device includes a carrier delivery chamber 300, a lifting mechanism 400, and a clamp rotating mechanism 500 as a clamp driving member. In addition, a plurality of lifting mechanisms 400 having the same structure may be arranged in the substrate lifting device.

[0053] 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 the opening 321. Although not shown in the figure, an opening through which the substrate carrier 100 passes and a carrier gate valve that can open and close the opening are provided in the carrier delivery chamber 300. Through these openings, the substrate 200 or the substrate carrier 100 is carried in and out of the carrier delivery chamber 300 by a conveying member such as a robot.

[0054] In addition, a carrier support member 330 is provided in the carrier delivery chamber 300, and the carrier support member 330 supports the substrate carrier 100 when the substrate 200 is placed on the substrate carrier 100. The carrier support member 330 supports the outer periphery of the substrate carrier 100 in a manner that does not hinder the movement of the support pins provided in the lifting mechanism. Alternatively, an opening may be provided in the carrier support member 330 in the area where the support pins pass. In addition, a conveying roller for conveying the substrate carrier 100 may be provided in the substrate loading chamber R1 (carrier delivery chamber 300). In this case, when the substrate 200 is placed on the substrate carrier 100, the conveying roller can support the substrate carrier 100.

[0055] In addition, a camera unit 350 (photographing unit) is provided in the carrier delivery chamber 300. In each figure, only one camera unit 350 is shown, but generally, a plurality of camera units 350 are provided. The control unit C can adjust (align) the positions of the substrate carrier 100 and the substrate 200 by acquiring position information from the image of the substrate carrier 100 and the substrate 200 photographed by the camera unit 350. In the carrier delivery chamber 300, the camera unit 350 is arranged so that at least a part of the side and end of the substrate 200 is included in the field of view in order to perform alignment based on the edge image of the substrate 200.

[0056] In addition, the imaging unit 350 can also function as a discriminating unit for discriminating the type of the substrate carrier 100 or the type of the substrate 200. For example, various marks can be added according to the type of the substrate carrier 100, and the type of the substrate carrier 100 can be discriminated based on the marks photographed by the imaging unit 350. The imaging unit 350 for alignment and the imaging unit 350 as the discriminating unit can be provided separately, and one of the imaging units 350 generally provided in plurality for alignment can also be used as the discriminating unit.

[0057] In this embodiment, for the lifting mechanism 400, only the support pin 411 is inserted into the carrier delivery chamber 300, and for the fixture rotation mechanism 500, only the push-in pin 511 is inserted into the carrier delivery chamber 300. In this way, it is possible to suppress the intrusion of lubricants or wear powder into the carrier delivery chamber 300. In addition, it is possible to form a structure in which the entire substrate lifting device is arranged in the substrate loading chamber R1, or it is possible to form a structure in which the above-mentioned carrier delivery chamber 300 is equivalent to the substrate loading chamber R1. In the latter case, most of the structures of the lifting mechanism (structures other than the support pin 411) and most of the structures of the fixture rotation mechanism 500 (structures other than the push-in pin 511) are arranged outside the substrate loading chamber R1.

[0058] The lifting mechanism 400 includes a plurality of support pins 411, a first plate 410 supporting the plurality of support pins 411, and a ball screw mechanism 420 as a first lifting member for lifting the first plate 410. The plurality of support pins 411 as a supporting member for supporting the substrate 200 are configured to be able to abut against the substrate 200 from the lower side in the vertical direction, and the substrate 200 is lifted and lowered by the support pins 411 moving up and down in the carrier delivery chamber 300. In addition, as the lifting member for lifting the first plate 410, a case where a ball screw mechanism is used is shown, but other known technologies such as a rack and pinion method can also be used as the lifting member.

[0059] In addition, the substrate lifting device includes an alignment mechanism 430 as an alignment member, and the alignment mechanism 430 adjusts the position of the substrate 200 relative to the substrate carrier 100 by moving the plurality of support pins 411 in the vertical direction relative to the lifting direction of the substrate 200. In addition, in the present embodiment, the lifting direction of the substrate 200 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 moving mechanism of the support pins 411 in the alignment mechanism 430, various known technologies such as a ball screw mechanism or a rack and pinion mechanism can be adopted.

[0060] By using 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 relative to the substrate carrier 100 can be adjusted.

[0061] The jig rotating mechanism 500 includes a plurality of press-in pins 511, a jig plate 510 supporting the plurality of press-in pins 511, and a ball screw mechanism 520 for raising and lowering the jig plate 510. The jig rotating mechanism 500 is a mechanism for rotating a jig 110 provided on a substrate carrier 100 in order to hold a substrate 200. A plurality of jigs 110 are provided on the substrate carrier 100, and the press-in pins 511 are provided at positions corresponding to the jigs 110. In addition, a case where a ball screw mechanism is used as a lifting member for raising and lowering the jig plate 510 is shown, but other known techniques such as a rack and pinion system can also be used as a lifting member.

[0062] As described above, the substrate carrier 100 includes a plurality of clamps 110 for holding the substrate 200. The clamps 110 are rotatably provided on the substrate carrier 100 in a state where a force is applied by a force-applying member in a direction of the substrate 200 clamped and held on the substrate carrier 100, i.e., in a first rotational direction. Furthermore, when the substrate 200 is placed on the substrate carrier 100 or when the substrate 200 is peeled off from the substrate carrier 100, the clamps 110 are forced by the push pins 511 to rotate in a second rotational direction. Figure 2 In (a), the left clamp 110 is rotatably provided on the substrate carrier 100 in a state where it is biased in the clockwise direction, and the right clamp 110 is rotatably provided on the substrate carrier 100 in a state where it is biased in the counterclockwise direction.

[0063] Next, the operation of the substrate lifting device when the substrate 200 is held 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 above the substrate carrier 100 .

[0064] The imaging unit 350 captures an image of the substrate 200 while the substrate 200 is supported by the plurality of support pins 411. The control unit C then obtains position information of the substrate 200 based on the image captured by the imaging unit 350 and determines the positional relationship between the substrate 200 and the substrate carrier 100.

[0065] Furthermore, the control unit C moves the substrate 200 in the X-axis direction and the Y-axis direction via the alignment mechanism 430 in order to adjust the position of the substrate 200 relative to the substrate carrier 100. As a result, the substrate 200 faces the substrate carrier 100 at a predetermined placement position.

[0066] After that, the support pins 411 are lowered by the lifting mechanism 400, and the ends of the plurality of support pins 411 are moved to a position lower than the lower surface of the substrate carrier 100. In this process, the substrate 200 is placed on the substrate carrier 100. In addition, a plurality of adsorption pads are provided on the substrate carrier 100, and the substrate 200 is adsorbed by the plurality of adsorption pads. In addition, if the substrate 200 is merely placed on the substrate carrier 100, adsorption by the adsorption pads may sometimes become insufficient, and therefore, it is also preferable to go through a process of making adsorption by the adsorption pads more reliable by pressing the substrate 200 downward.

[0067] When the support pins 411 are lowered, the clamp 110 is pressed by the pressing pins 511 so that the substrate 200 can be placed on the substrate carrier 100. Then, after the substrate 200 is placed on the substrate carrier 100, the clamp plate 510 is lowered by the clamp rotating mechanism 500. As a result, the pressing pins 511 leave the clamp 110, and the clamp 110 rotates in the first rotation direction to clamp the substrate 200 to the substrate carrier 100. Then, as shown in FIG. Figure 2 As shown in (b), the substrate 200 is held by the substrate carrier 100. The substrate 200 held as described above is carried out from the carrier delivery chamber 300 together with the substrate carrier 100, and is carried to the reversing chamber R2.

[0068] <Alignment of Substrate to Substrate Carrier>

[0069] The alignment and placement of the substrate 200 on the substrate carrier 100 in the alignment device included in the film forming apparatus of the present embodiment will be described in more detail.

[0070] As described above, the control unit C obtains the position information of the substrate 200 based on the image captured by the imaging unit 350 in the substrate loading chamber R1, and grasps the positional relationship with the substrate carrier 100. Then, the control unit C moves the substrate 200 in the X-axis direction and the Y-axis direction through the alignment mechanism 430. Thus, after the substrate 200 faces the substrate carrier 100 at a predetermined loading position, the substrate 200 is loaded on the substrate carrier 100 through the lifting mechanism 400.

[0071] In this embodiment, an optical imaging device is used as the imaging component 350, in which the light amount of illumination light from the light source, the shutter speed, the 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, the shutter speed, and the gain value. Therefore, the control unit C functions as a parameter adjustment unit.

[0072] The control unit C of this embodiment analyzes the image captured by the imaging unit 350, identifies the edge of the substrate 200, and obtains the position information of the substrate 200 based on the edge. Figure 3 (a) to (d) describe a procedure for acquiring position information of the substrate 200 from an image captured by the imaging unit 350 . Figure 3 (a) shows an image captured by the imaging unit 350 . Figure 3 (b) shows an edge image generated by the control unit C based on the image captured by the imaging unit 350 . Figure 3 (c) shows a case where the edge of the substrate 200 is properly detected in the edge image. Figure 3 (d) shows a case where a flaw on the substrate carrier 100 is mistakenly recognized as an edge of the substrate 200 in the edge image as a comparative example.

[0073] The imaging component 350 of this embodiment takes one of the four corners of the substrate 200 having a substantially rectangular surface as an imaging object. Figure 3 (a) shows the inside of the field of view 351. Figure 3 In (a), the same color represents the region composed of the same material. That is, the inside of the substrate carrier 100 and the inside of the substrate 200 have similar pixel values.

[0074] exist Figure 3 At the moment of shooting (a), since the substrate 200 is located on the upper side of the substrate carrier 100 in the vertical direction, the substrate 200 overlaps a portion of the substrate carrier 100 as seen from the camera component 350 disposed above the substrate loading chamber R1. Within the range of the field of view angle 351, the substrate 200 has an edge 210A in a direction parallel to the substrate conveying direction and an edge 210B in a direction perpendicular to the substrate conveying direction. Moreover, in this example, the corner of the substrate 200 is in a shape in which a portion is missing (corner edge 210C). In addition, a carrier mark may be formed on a portion of the substrate carrier 100. In addition, Figure 3 (a) shows a captured image of the substrate 200 when the substrate 200 is captured by the imaging unit 350 and the substrate 200 is in a predetermined reference position. Here, the reference position refers to a target position in design. Even if the position of the substrate 200 is slightly deviated from the reference position, the reference position of the substrate 200 is set so that the edges 210A and 210B of the substrate 200 are within the field of view angle 351.

[0075] The control unit C performs image processing on the captured image to generate an edge image. The edge image can be generated by using existing edge extraction processing, for example, edge detection filters such as differential filters can be applied to image data to generate an edge image. In edge extraction, noise reduction processing such as smoothing can also be performed as needed. Figure 3(b) As shown in FIG. 1 , the portion with a large change in pixel value from the adjacent pixel is extracted as an edge. In other words, the portion other than the edge and the transition portion of the edge are detected by the difference in contrast. As a result, in the edge image, the portion other than the edge and the transition portion of the edge are emphasized as the edges 210A, 210B and the corner edge 210C of the outline of the substrate 200.

[0076] When the edge of the substrate 200 is properly detected, as shown in FIG. Figure 3 As shown in (c), the control unit C obtains a first reference line 220A along the edge 210A in the edge image and a second reference line 220B along the edge 210B. The control unit C obtains the position information of the in-plane direction of the substrate 200 from the first reference line 220A and the second reference line 220B that intersect each other. Then, the substrate 200 is aligned with respect to the substrate carrier 100 based on the position information. In this way, in this embodiment, the position information of the substrate is obtained from the position information of the two edges of the substrate.

[0077] When the edge image is generated, if there is a scratch or stain on the substrate 200 or the substrate carrier 100, the scratch or stain on the edge image may be emphasized in the same manner as the edge of the substrate 200. Therefore, during edge detection, the scratch or stain may be mistakenly recognized as an edge, which may affect alignment. Figure 3 As in the comparative example shown in (d), if there is a scratch Sc on the substrate carrier 100, the first reference line 220A may be generated along the scratch Sc instead of the edge 210A. In this way, if the first reference line 220A is generated at an incorrect position by misidentifying the scratch Sc as an edge, alignment is performed based on incorrect position information of the substrate 200. Furthermore, if alignment is not performed properly, the substrate 200 cannot be placed at the correct position relative to the substrate carrier 100, which may cause various problems such as cracks in the substrate when being transported by the transport component.

[0078] <Edge Detection Method>

[0079] In the present invention, in order to improve the edge detection accuracy of the substrate 200, a detection area is set in the edge image, and whether the detected line segment is the edge of the substrate is determined based on the length of the line in the detection area. Figure 4 (a) to (d) describe in detail the edge detection method in the edge image of the present invention by taking the case where a scratch Sc exists on the substrate carrier 100 as an example.

[0080] When the control unit C as the edge detection component generates an edge image, Figure 4As shown in (a), a rectangular first detection area T1 and a second detection area T2 are set in the edge image. 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 area T2 is an area for detecting the edge 210B, and the second detection area T2 is set so that the edge 210B is included in the area. When the extending direction of the edge 210A when the substrate 200 is at the reference position is set as the first direction D1, and the extending direction of the edge 210B is set as the second direction D2, the first detection area T1 is a rectangle long in the second direction D2, and the side of the first detection area T1 is parallel to the first direction D1 or the second direction D2. On the other hand, the second detection area T2 is a rectangle long in the first direction D1, and the side of the second detection area T2 is parallel to the first direction D1 or the second direction D2. By setting the detection area in this way, even if the substrate 200 is slightly deviated from the reference position during imaging, the desired edge is included in the detection area. In addition, the shape and size of each detection area can be appropriately changed according to the substrate or substrate carrier. Hereinafter, the edge detection method of the present invention will be described by taking the case where a part of the flaw Sc is included in the first detection area T1 as an example.

[0081] After setting the detection area, the control unit C detects line segments along the reference direction of the detection direction from within the detection area. Here, the reference direction of the detection area is set to the direction along the edge of the substrate 200 to be detected. In addition, the line segment can be set to allow a slight tilt relative to the reference direction, and when the angle between the reference direction and the line segment is greater than a specified value, it is not detected as a line segment. In this embodiment, the control unit C divides the detection area in the detection direction, and detects the line segments in each divided area in sequence starting from the divided area outside the substrate 200. Figure 4 As shown by the arrow in (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 area T1, instead of the edge 210A, a part of the scratch Sc on the outside of the substrate 200 is first detected as the line segment L1a. On the other hand, in the second detection area T2, a part of the edge 210B is detected as the line segment L2a. In addition, when detecting the line segment, even if there is a slight interruption in the middle, it can be regarded as no interruption and detected as a line segment.

[0082] When a line segment is detected, the control unit C determines whether the detected line segment is the 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 reference direction of the detection area as the score value SV, and when the score value SV is greater than a predetermined value, the line segment is detected as the edge of the substrate 200. In this embodiment, when the score value is greater than 80%, the line segment is detected as the edge of the substrate 200. That is, in each of the first detection area T1 and the second detection area T2, the threshold of the score value for detecting the line segment as the edge of the substrate 200 is 80%. In addition, in this embodiment, the same threshold is set in the first detection area T1 and the second detection area T2, but different thresholds may be set in each detection area, such as setting the first threshold of the first detection area T1 to 90% and the second threshold of the second detection area T2 to 80%.

[0083] like Figure 2 As shown in (b), in the first detection area T1, when calculating the score value SV, the length Q1 of the first detection area T1 in the first direction D1 is used. By using the width of the substrate 200 in a direction substantially parallel to the direction in which the edge 210A extends to calculate the score value SV, the threshold of the score value SV can be set higher, thereby reducing the misidentification of the edge. If the control unit C detects a part of the flaw Sc as the line segment L1a, the score value SV1a=P1a / Q1[%] is calculated based on 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. Here, when the score value SV1a is lower than the threshold, the control unit C determines that the line segment L1a is not the edge of the substrate 200 and starts the detection of 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 the edge of the substrate 200.

[0084] When the detection of a new line segment starts in the first detection area T1, as shown in FIG. Figure 4 As shown in (c), a portion of the edge 210A is then detected as a line segment L1b. And, based on the length Q1 of the first direction D1 of the first detection area T1 and the length P1b of the line segment L1b in the first direction D1, a score value SV1b=P1b / Q1[%] is calculated. Since the edge 210A extends across the first detection area T1, the score value SV1b is calculated to be 100%. And, the control unit C sets the score value SV1b to a threshold value of 80% or more and detects the line segment L1b as the edge of the substrate 200. In addition, when the length of the detected line segment is greater than the length of the reference direction of the detection area and the score value is greater than 100%, the line segment may be detected as an edge, and the subsequent line segment detection and determination are not performed.

[0085] In the second detection area T2, when calculating the score value, the length Q2 of the second direction D2 of the second detection area T2 is used. In the second detection area T2, there are no scratches or stains, and a portion of the edge 210B is first detected as a line segment L2a. Then, the score value SV2a=P2a / Q2[%] is calculated based on the length Q2 of the second direction D2 of the second detection area T2 and the length P2a of the second direction D2 of the line segment L2a. Since the edge 210A extends across the first detection area T1, the score value SV1b is calculated to be 100%. Then, the control unit C sets the score value SV2a to a threshold value of 80% or more and detects the line segment L2a as the edge of the substrate 200.

[0086] like Figure 4 As shown in (d), the control unit C obtains the first reference line 220A along the edge 210A and the second reference line 220B along the edge 210B as the position information of the substrate 200 based on the edges detected in each detection area through the above steps. That is, since the position information of the two sides of the surface of the substrate 200 can be obtained, the position information of the substrate 200 in the in-plane direction of the substrate 200 can be obtained.

[0087] In addition, in this embodiment, whether a line segment is an edge is determined based on the length of the line segment detected in the detection area, but in addition to the length of the line segment, it can also be determined based on the angle or thickness of the line segment. By increasing the edge determination criterion in this way, higher-precision edge detection can be performed.

[0088] <Edge Detection Processing Flow>

[0089] Reference Figure 5 , the edge detection process of the substrate 200 of this embodiment is described. When the substrate 200 is carried into the substrate loading chamber R1, the substrate 200 is arranged above the substrate carrier 100 in such a manner that the edge of the substrate 200 is roughly included in the field of view 351 of the camera component 350. At this time, the substrate 200 is arranged at the reference position, but a slight deviation from the reference position is allowed. And, as a shooting process, after the edge image of the substrate is shot by the camera component 350, the control unit C starts edge detection in the edge image (S100).

[0090] First, in the area setting process of step S101, the first detection area T1 and the second detection area T2 are set. At this time, a portion of the edge 210A (first side) of the substrate 200 located at the substantially reference position is included in the first detection area T1, and a portion of the edge 210B (second side) is included in the second detection area T2.

[0091] In the line segment detection process of step S102, the control unit C detects line segments based on the edge image. As described above, in this embodiment, the detection direction is set to the direction from the outside to the inside of the substrate 200. Therefore, when the edge image includes a flaw of the substrate carrier 100, the flaw of the substrate carrier 100 is detected as a line segment before the edge of the substrate 200.

[0092] In the length acquisition process of step S103, the length of the line segment detected in step S102 is acquired. Then, in the score value calculation process of step S104, the score value of each line segment is acquired based on the length of the line segment acquired 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 direction D1 of the first detection area T1 is calculated as a score value. Then, in the second detection area T2, a second ratio of the length of the second line segment to the length Q2 of the second direction D2 of the second detection area T2 is calculated as a score value.

[0093] In the determination process of step S105, it is determined whether the score value obtained in step S104 exceeds the threshold value. Here, if it is determined that the score value does not exceed the threshold value ("No" in S105), it is determined that the line segment detected in step S102 is not the edge of the substrate 200, and the line segment detection process of step S106 is entered to start the detection of a new line segment along the detection direction. Then, if a new line segment is detected in step S102, the process from step S103 to step S105 is repeated again. In addition, it can also be configured to report an error to the user if a new line segment cannot be detected in step S106.

[0094] In step S105, when it is determined that the score value of the line segment exceeds the threshold value ("Yes" in S105), in the edge detection process of step S107, the edge of the substrate 200 is detected based on the determination result of step S105. In each detection area, if the edge of the substrate 200 is detected, the edge detection ends (S108). Then, based on the position information of the substrate 200 obtained from the detected edge, the substrate 200 is aligned with the substrate carrier 100 as an alignment process.

[0095] As described above, according to this embodiment, even when there are scratches or stains on the substrate carrier 100, it is possible to reduce the possibility of misidentifying the scratches or stains as the edge of the substrate 200, and to detect the edge of the substrate 200 with high accuracy. Furthermore, it is possible to suppress the occurrence of problems such as a decrease in alignment accuracy and damage to the substrate.

[0096] In addition, the structure of the present invention is not limited to the above structure, and various changes can be made within the scope of not losing the sameness as the invention embodied in the above embodiment. For example, in the above embodiment, the present invention is applied to edge detection when aligning a substrate relative to a substrate carrier in a substrate loading chamber, but the present invention can also be applied when aligning a substrate in other chambers. In addition, in the above embodiment, as a score value used in edge detection of a substrate, the ratio of the length of a line segment to the length of a detection area is used, but the length of the line segment itself, the difference between the length of the line segment and the length of the detection area, etc. can also be used as a score value.

[0097] In addition, Figure 5 In the edge detection process shown, the judgment is made by comparing the score value of the line segment and the threshold value, but the present invention is not limited to this. For example, a judgment process can also be used to compare the line segments detected in the detection area and detect the line segment with the highest score as the edge. Figure 6 As a variation of the above-described embodiment, a method of comparing line segments detected within a detection area and detecting a line segment with the highest score as an edge is described.

[0098] When edge detection is started (S200), first, as step S201, 0 is substituted into the [maximum score value]. Also, the method of setting the detection area from step S202 to step S205, detecting line segments within the detection area, and obtaining the score values ​​of the line segments is similar to the method of Figure 5 The edge detection process shown is the same.

[0099] In the determination process of steps S206, 208, and 209, various determinations are made on the score value obtained in step S204. First, in step S206, it is determined whether the score value is greater than 100. Here, if it is determined that the score value is greater than 100 ("Yes" in S206), the process proceeds to step S207, and the line segment with a score value greater than 100 is determined as the edge of the substrate 200, and the edge detection ends (S214).

[0100] 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 to determine whether the score value is above the threshold value. Here, if the score value is above the threshold value ("Yes" in S208), the process proceeds to step S209 to determine whether the score value is greater than the [maximum score value]. Then, 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 the detection of all line segments in the detection area is completed. In addition, if it is determined in step S208 that the score value is less than the threshold value ("No" in S208), or if it is determined in step S209 that the score value is less than the [maximum score value] ("No" in S209), the process proceeds to step S211 without substituting the new value into the [maximum score value]. In addition, the determination steps are not limited to be performed in the above order, and the order of step S208 and step S209 may be swapped. Step S208 may be performed only for the highest score value after all line segments are detected.

[0101] In step S211, if it is determined that the detection of all line segments has not been completed ("No" in S211), the process proceeds to the line segment detection process of step S212, and the detection of new line segments is started along the detection direction. Then, if a new line segment is detected in step S203, the process from step S204 to step S211 is repeated again.

[0102] In step S211, when it is determined that the detection of the line segment is completed ("Yes" in S211), in the edge detection process of step S213, the line segment with the [maximum score value] is detected as the edge of the substrate 200 from the line segments detected so far. In each detection area, if the edge of the substrate 200 is detected, the edge detection is completed (S214). Then, based on the position information of the substrate 200 obtained from the detected edge, the substrate 200 is aligned with the substrate carrier 100 as an alignment process. In addition, it can also be configured to report an error to the user when no line segment is detected in the detection area or when a line segment with a score value above the threshold is not detected. As described above, by adding the determination condition that a line segment with a score value of 100 or more or the longest line segment among the detected line segments is determined as the edge of the substrate, the edge of the substrate can be detected with higher accuracy.

[0103] <Film Forming Room>

[0104] Reference Figure 7, the film forming process in the film forming chamber R3 is 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 on the substrate carrier 100 is supported in a downwardly facing state while being positioned in the film forming chamber R3. In addition, a mask M is also arranged on the lower side of the substrate 200 in a state positioned relative to the substrate 200. An opening is provided at a position of the mask M corresponding to a position where a thin film is formed on the substrate 200. Thus, film formation is performed on the substrate 200 held on the substrate carrier 100 via the mask M.

[0105] In this embodiment, film formation (evaporation) based on vacuum evaporation is performed. Specifically, the film forming material evaporates or sublimates from the evaporation source 600, and the film forming material is evaporated on the substrate 200 to form a thin film on the substrate 200. Since the evaporation source 600 is a well-known technology, its detailed description is omitted. For example, the evaporation source 600 can be composed of a container such as a crucible for accommodating the film forming material and a heating device for heating the container. In addition, the film forming source is not limited to the evaporation source 600, and the film forming source can also be a sputtering cathode for film formation by sputtering.

[0106] <Method for manufacturing electronic device>

[0107] Next, an example of a method for manufacturing an electronic device using the film-forming apparatus of this embodiment is described. Hereinafter, as an example of an electronic device, the structure of an organic EL display device is shown, and an example of a method for manufacturing the organic EL display device is described.

[0108] First, the organic EL display device to be manufactured will be described. Figure 8 (a) is an overall view of the organic EL display device 700. Figure 8 (b) shows the cross-sectional structure of one pixel.

[0109] like Figure 8 As shown in (a), in the display area 701 of the organic EL display device 700, a plurality of pixels 702 having a plurality of light-emitting elements are arranged in a matrix. The details will be described later, and each light-emitting element has a structure having an organic layer clamped by a pair of electrodes. In addition, the pixel mentioned here refers to the smallest unit that can display the desired color in the display area 701. In the case of the organic EL display device of this embodiment, the pixel 702 is composed of a combination of a first light-emitting element 702R, a second light-emitting element 702G, and a third light-emitting element 702B that display different light. The pixel 702 is mostly composed of a combination of a red light-emitting element, a green light-emitting element, and a blue light-emitting element, but it can also be a combination of a yellow light-emitting element, a cyan light-emitting element, and a white light-emitting element. There is no particular limitation as long as it is at least one color.

[0110] Figure 8 (b) Yes Figure 8(a) is a partial cross-sectional schematic diagram of the BB line. The pixel 702 is composed of a plurality of light-emitting elements, each of which has a first electrode (anode) 704, a hole transport layer 705, any one of the light-emitting layers 706R, 706G, and 706B, an electron transport layer 707, and a second electrode (cathode) 708 on a substrate 703. Among them, the hole transport layer 705, the light-emitting layers 706R, 706G, 706B, and the electron transport layer 707 are equivalent to organic layers. In addition, 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 into patterns corresponding to the light-emitting elements (sometimes also described as organic EL elements) that emit red, green, and blue, respectively.

[0111] In addition, 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 by a plurality of light-emitting elements 702R, 702G, and 702B, or may be formed for each light-emitting element. In addition, in order to prevent the first electrode 704 and the second electrode 708 from being short-circuited due to foreign matter, an insulating layer 709 is provided between the first electrode 704. Furthermore, since the organic EL layer is degraded by moisture or oxygen, a protective layer 710 is provided to protect the organic EL element from moisture or oxygen.

[0112] exist Figure 8 In (b), the hole transport layer 705 and the electron transport layer 707 are represented by one layer, but they may be formed by a plurality of layers including a hole blocking layer and an electron blocking layer depending on the structure of the organic EL display element. In addition, a hole injection layer having an energy band structure that allows smooth hole injection from the first electrode 704 to the hole transport layer 705 may be formed between the first electrode 704 and the hole transport layer 705. Similarly, an electron injection layer may also be formed between the second electrode 708 and the electron transport layer 707.

[0113] Next, an example of a method for manufacturing an organic EL display device will be described in detail.

[0114] First, a circuit (not shown) for driving the organic EL display device and a substrate (mother glass) 703 on which a first electrode 704 is formed are prepared.

[0115] Acrylic resin is formed by spin coating on the substrate 703 having the first electrode 704 formed thereon, and the acrylic resin is patterned by photolithography to form an opening in the portion where the first electrode 704 is formed, thereby forming an insulating layer 709. The opening corresponds to a light emitting region where the light emitting element actually emits light.

[0116] The substrate 703 patterned with the insulating layer 709 is placed on a substrate carrier provided with an adhesive member. The substrate 703 is held by the adhesive member. The substrate 703 is carried into the first organic material film forming device, turned over, and the 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 evaporation. In fact, since the hole transport layer 705 is formed to a larger size than the display area 701, a high-precision mask is not required.

[0117] Next, the substrate 703 with the hole transport layer 705 formed thereon is carried into the second organic material film forming apparatus, the substrate and the mask are aligned, the substrate is placed on the mask, and a red light emitting layer 706R is formed on the portion of the substrate 703 where the red light emitting element is arranged.

[0118] Similar to the film formation of the light-emitting layer 706R, the light-emitting layer 706G emitting green is formed by the third organic material film-forming device, and the light-emitting layer 706B emitting blue is formed by the fourth organic material film-forming device. After the film formation of the light-emitting layers 706R, 706G, and 706B is completed, the electron transport layer 707 is formed on the entire display area 701 by the fifth film-forming device. The electron transport layer 707 is formed as a layer common to the three-color light-emitting layers 706R, 706G, and 706B.

[0119] The substrate on which the electron transport layer 707 has been formed is moved by a metallic vapor deposition material film forming apparatus, and the second electrode 708 is formed.

[0120] After that, the substrate 703 is moved to a plasma CVD device to form a protective layer 710, completing the film forming process on the substrate 703. After flipping, the substrate 703 is separated from the substrate carrier by peeling off the adhesive member from the substrate 703. After that, the organic EL display device 700 is completed by cutting.

[0121] From the time when the substrate 703 patterned with the insulating layer 709 is carried into the film forming apparatus until the film forming of the protective layer 710 is completed, if the substrate is exposed to an atmosphere containing moisture or oxygen, the light-emitting layer composed of the organic EL material may be degraded by moisture or oxygen. Therefore, in this embodiment, the substrate is carried in and out of the film forming apparatus in a vacuum atmosphere or an inert gas atmosphere. Description of Reference Numerals

[0122] 100…carrier (holding component), 200…substrate, 220A…intersection (first reference point), 220B…intersection (second reference point), 350…imaging component (shooting component), 411…support pin (support component), C…control unit (determination component), L1…distance.

Claims

1. An alignment device for aligning a substrate relative to a holding member holding the substrate, characterized in that: The alignment device comprises: a photographing member for photographing an edge image including an edge of the substrate held by the holding member; an edge detection component, which sets a detection area in the edge image and detects an edge of the substrate along a reference direction of the detection area from within the detection area; as well as an alignment component, which aligns the substrate relative to the holding component based on the edge detected by the edge detection component, The edge detection unit 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 the line segment detected from within the detection area along the reference direction.

2. The alignment device according to claim 1, characterized in that The substrate has a substantially rectangular surface. The reference direction is a direction parallel to the side of the substrate when the substrate is in a predetermined reference position.

3. The alignment device according to claim 1, characterized in that: The detection area is a rectangle having sides parallel to the reference direction.

4. The alignment device according to claim 1, characterized in that The edge detection unit calculates a ratio of the length of the line segment to the length of the detection area in the reference direction, and determines that the line segment is an edge of the substrate when the ratio is equal to or greater than a predetermined value.

5. The alignment device according to claim 1, characterized in that: The edge detection unit determines that the line segment is an edge of the substrate when the length of the line segment is equal to or greater than the length of the detection area in the reference direction.

6. The alignment device according to claim 1, characterized in that: The edge detection unit determines that the longest line segment among the line segments detected within the detection area is the edge of the substrate.

7. The alignment device according to claim 1, characterized in that: The imaging unit captures the substrate in a manner such that a first side extending in a first direction of the substrate and a second side extending in a second direction different from the first direction are included in the edge image when the substrate is at a predetermined reference position. The edge detection unit sets a first detection area including the first side and a second detection area including the second side as the detection area.

8. The alignment device according to claim 7, characterized in that The first detection area is a rectangle that is long in the second direction, The second detection area is a rectangle that is long in the first direction.

9. The alignment device according to claim 7, characterized in that: The edge image is a rectangle that is long in the first direction, A length of the first detection area in the first direction is longer than a length of the second detection area in the second direction.

10. The alignment device according to claim 7, characterized in that The edge detection component calculating a first ratio of a length of a first line segment within the first detection area to a length of the first detection area in the first direction, and determining that the first line segment is an edge of the substrate when the first ratio is greater than a first threshold value, 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 when the second ratio is greater than or equal to a second threshold, the second line segment is determined to be an edge of the substrate.

11. The alignment device according to claim 1, characterized in that The edge detection section detects the line segment from the detection area based on the contrast of the edge image.

12. The alignment device according to claim 1, characterized in that The edge detection component 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.

13. The alignment device according to claim 1, characterized in that The edge detection component 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.

14. A film forming device, characterized in that: The film forming device comprises: The alignment device of any one of claims 1 to 13; and The film forming source discharges a film forming material toward the substrate held by the holding member.

15. An alignment method, characterized in that: The alignment method comprises: a photographing step of photographing an edge image including an edge of the substrate held by a holding member for holding the substrate; A region setting step of setting a detection region in the edge image; A line segment detection step of detecting, within the detection area, line segments along a reference direction of 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 according to the length of the line segment and the length of the reference direction of the detection area; as well as The alignment step aligns the substrate with respect to the holding member based on the edge of the substrate detected in the edge detection step.

Images