Alignment device

Abstract

The present application provides an alignment device that suppresses positional deviation during alignment of a substrate and a mask in film formation, and improves alignment accuracy. The alignment device includes an alignment mechanism that adjusts the relative positions of the substrate and the mask in a plane along the film formation surface of the substrate, a moving mechanism that moves the relative positions of the substrate and the mask in a cross direction intersecting the plane, and a measurement mechanism that measures the position of the substrate in the plane. The measurement mechanism measures first position information of a jig mark carried by a jig different from the substrate in a state where the jig is arranged at a first height, and measures second position information of the jig mark in a state where the jig is arranged at a second height.

Description

Technical Field

[0001] This invention relates to an alignment device. Background Technology

[0002] Display devices equipped with flat panel displays such as OLEDs and LCDs are widely used. Among them, OLED displays excel in response speed, viewing angle, and thinness, making them suitable for monitors, televisions, smartphones, and other devices.

[0003] In the manufacturing process of organic EL displays, a mask deposition method is known to form a film with a predetermined pattern by depositing an opening in a mask onto a glass substrate. In this method, after aligning the mask with the glass substrate, the mask and the glass substrate are brought into close contact for film deposition. High-precision alignment of the mask and the glass substrate is crucial for achieving high-precision film deposition using this method.

[0004] Patent Document 1 describes a method for aligning a mask and a glass substrate using mask marks on a mask and substrate marks on a glass substrate. Patent Document 1 also proposes a method for calculating the offset based on the positional deviation of the alignment marks after the glass substrate and mask are in close contact, thereby achieving high-precision alignment.

[0005] [Existing Technical Documents]

[0006] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2020-105629 Summary of the Invention

[0008] [The problem the invention aims to solve]

[0009] In Patent Document 1, as described above, the offset is calculated based on the positional deviation of the alignment marks after the substrate and mask are in close contact. However, when the optical axis of the camera optical system that captures the alignment marks is tilted relative to the movement of the Z-axis sliding member of the carrier (the direction in which the carrier moves along the sliding member), even if the positions of the substrate marks and mask marks are consistent on the camera display, the positional relationship between the substrate marks and mask marks projected onto the mask surface will deviate. Hereinafter, this positional deviation will be referred to as optical axis deviation. Due to the influence of this optical axis deviation, the alignment accuracy may sometimes decrease. In the method described in Patent Document 1, due to the influence of the deviation caused by the contact between the substrate and the mask, it is difficult to separate the component of optical axis deviation inherent in the device itself. Therefore, it is difficult to obtain a correct correction value for errors inherent in the device itself, such as optical axis deviation.

[0010] The present invention was made in view of the above-mentioned problems, and its purpose is to suppress the positional deviation of the substrate and the mask during film formation and improve the alignment accuracy.

[0011] [Solutions for solving the problem]

[0012] The present invention adopts the following structure. That is,

[0013] An alignment device comprising:

[0014] An alignment mechanism that adjusts the relative position of the substrate and the mask in a plane along the film-forming surface of the substrate;

[0015] A moving mechanism that moves the relative position of the substrate with respect to the mask in a direction intersecting the plane; and

[0016] A measuring mechanism that measures the position of the substrate in the plane.

[0017] The alignment device is characterized in that...

[0018] With a clamp, different from the substrate, positioned at a first height, the measuring mechanism measures the first position information of the clamp markings on the clamp.

[0019] With the fixture positioned at the second height, the measuring mechanism measures the second position information of the fixture mark.

[0020] [Invention Effects]

[0021] According to the present invention, positional deviation between the substrate and the mask during film formation can be suppressed, thereby improving alignment accuracy. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the entire production line for a vacuum evaporation deposition unit.

[0023] Figure 2 This is a schematic diagram of the alignment device in a vacuum evaporation apparatus.

[0024] Figure 3 This is an enlarged schematic diagram of the carrier and mask support of the alignment device.

[0025] Figure 4 This is a flowchart of the process for obtaining correction values.

[0026] Figure 5 This is a flowchart of the alignment process.

[0027] Figure 6 It is a graph showing the change of the marker coordinates within the camera's field of view.

[0028] Figure 7 It is a graph showing the deviation and correction value of the Z-height and X-direction of the correction mark.

[0029] Figure 8 This is a diagram showing the structure of the substrate markings and mask markings.

[0030] Figure 9 This is a diagram showing the structure of the fixture and correction marks.

[0031] Figure 10 It is a diagram illustrating the manufacturing process of electronic devices.

[0032] [Explanation of Labels in the Attached Image]

[0033] 10: Glass substrate, 12: Mask, 15: Correction mark, 24: Carrier Z-axis lifting slider

[0034] 26: Alignment platform; 31: Alignment camera; 40: Correction fixture. Detailed Implementation

[0035] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the following description is merely illustrative of preferred structures of the present invention, and the scope of the present invention is not limited to these structures. Moreover, unless otherwise specifically stated, the hardware and software structures, processing flows, manufacturing conditions, dimensions, materials, shapes, etc., of the apparatus described below are not intended to limit the scope of the present invention.

[0036] When forming a film with a desired pattern on a substrate, a mask with a mask pattern adapted to the shape of the film is used. By using multiple masks, the layers to be formed can be arbitrarily configured. In order to form the film at the desired location on the substrate, the relative position (alignment) of the substrate and the mask needs to be adjusted with high precision.

[0037] This invention can be understood as an alignment method and alignment apparatus for alignment (adjustment of the relative position of the substrate and the mask) when forming a film by attaching a film-forming material to a substrate or other film-forming object via a mask. This invention can also be understood as a film-forming method and film-forming apparatus using the above-described alignment method and alignment apparatus. When film formation is performed by vapor deposition, this invention can also be understood as a vapor deposition method and vapor deposition apparatus. This invention can also be understood as an adjustment method, adjustment apparatus, or adjustment fixture for adjusting the above-described alignment apparatus. This invention can also be understood as a manufacturing method and manufacturing apparatus for electronic devices using a film-formed substrate. This invention can also be understood as a control method for each of the above-described apparatuses.

[0038] This invention is preferably applied to cases where a thin film material layer with a desired pattern is formed on the surface of a substrate via a mask. The substrate material can be any material such as glass, resin, metal, or silicon. The film-forming material can be any material such as organic or inorganic materials (metals, metal oxides). The technology of this invention is typically applicable to manufacturing apparatuses for electronic devices and optical components. It is particularly suitable for organic electronic devices such as organic EL displays, organic EL display devices using such organic EL displays, thin-film solar cells, and organic CMOS image sensors. However, the application of this invention is not limited to these.

[0039] <Example 1>

[0040] (Manufacturing line)

[0041] Figure 1 This is a top view schematically illustrating the structure of a manufacturing line for electronic devices. Such a manufacturing line is called a film deposition system that includes film deposition apparatus. Here, a manufacturing line for organic EL displays will be described. In the case of manufacturing organic EL displays, a substrate of a specified size is fed into the manufacturing line, and after the organic EL and metal layers are deposited, post-processing steps such as substrate cutting are performed.

[0042] It should be noted that this invention is not limited to Figure 1 Alignment in such a series-connected film deposition system. For example, the substrate can also be applied to alignment in a cluster-type film deposition system in which multiple film deposition devices are arranged around a transfer robot for film deposition. Moreover, the present invention can also be applied to film deposition devices that do not have a carrier.

[0043] The film-forming apparatus of this embodiment is a vacuum evaporation apparatus that uses an evaporation source to deposit evaporation material onto a substrate. The manufacturing line is located within the evaporation apparatus of an overall vacuum evaporation production line and includes at least a glass substrate loading chamber 101, a carrier assembly chamber 102, a mask assembly chamber 103, an alignment chamber 104, a film-forming chamber 105, and a glass substrate discharge chamber 109. In this embodiment, as... Figure 1 As shown, it also includes a transfer chamber 106, a mask separation chamber 107, a carrier separation chamber 108, a mask transfer chamber 110, and a carrier transfer chamber 111.

[0044] A glass substrate is fed into the glass substrate loading chamber 101. In the carrier assembly chamber 102, the carrier 11 and the glass substrate 10 are assembled. In the mask assembly chamber 103, the carrier 11 and the mask 12 are assembled. In the alignment chamber 104, the carrier and the mask are aligned with high precision. In the film deposition chamber 105, a film deposition process is performed on the glass substrate 10. The film-deposited glass substrate is discharged from the glass substrate discharge chamber 109.

[0045] The glass substrate input chamber 101 receives the glass substrate 10 from upstream and feeds it onto the conveyor line for downstream processing. In the carrier assembly chamber 102, the glass substrate 10 is assembled with a carrier 11 used for conveying the glass substrate 10, which clamps the glass substrate 10 and conveys it downstream. In the mask assembly chamber 103, the carrier 11 and mask 12 are assembled and conveyed downstream respectively. When the carrier 11 and mask 12 are fed from the mask assembly chamber 103 into the alignment chamber 104, high-precision alignment is performed using substrate marks mounted on the glass substrate 10 and mask marks mounted on the mask 12. The carrier 11 and mask 12 abut against each other and are conveyed downstream to the film deposition chamber 105. This alignment process will be described later. The film deposition chamber 105 is equipped with an evaporation source (film deposition source) for heating and evaporating the film-forming material, and performs film deposition processing on the glass substrate 10 via the mask 12.

[0046] The carrier 11 and mask 12 are fed into the mask separation chamber 107 via the transfer chamber 106. In the mask separation chamber 107, the mask 12 separates from the carrier 11. The separated mask 12 returns to the circulation path via the mask transfer chamber 110. In the carrier separation chamber 108, the carrier 11 separates from the glass substrate 10. The separated carrier 11 returns to the circulation path via the carrier transfer chamber 111. The glass substrate 10, having completed the film deposition process, is sent to the next process from the glass substrate delivery chamber 106.

[0047] It should be noted that the manufacturing line can also be configured such that the carrier 11 holding the glass substrate 10 is mounted on the mask 12, and the carrier 11 is flipped up and down so that the film-forming material is attached to the glass substrate 10 from below. In this case, the flipping is performed again after film formation is completed. Moreover, each chamber of the manufacturing line is preferably maintained in a high vacuum state during the manufacturing process of the organic EL display panel.

[0048] (Alignment device)

[0049] Figure 2 This is a cross-sectional view showing the structure of the alignment chamber 104. In the alignment chamber 104, the carrier 11 and the mask 12 are respectively placed from the mask assembly chamber 103 onto the carrier transfer roller 20 and the mask transfer roller 21 for transport. Furthermore, a series of processes are performed as follows: alignment (alignment) is performed to adjust the relative positional relationship between the glass substrate 10 and the mask 12, the carrier 11 with the glass substrate 10 fixed abuts against the mask 12, and the carrier 11 is transported to the next process film deposition chamber 105 according to each mask 12.

[0050] In the following description, an XYZ orthogonal coordinate system is used, with the vertical direction defined as the Z direction. In the XYZ orthogonal coordinate system, when the substrate is fixed parallel to the horizontal plane (XY plane) during film deposition, the direction in which one set of opposite sides of the rectangular glass substrate 10 extends is defined as the X direction, and the direction in which the other set of sides extends is defined as the Y direction. Furthermore, θ represents the rotation angle about the Z-axis.

[0051] Alignment chamber 104 has a vacuum chamber 22. The interior of vacuum chamber 22 is maintained in a vacuum atmosphere or an inactive gas atmosphere such as nitrogen. A mask support unit 16 and a carrier support unit 17 are disposed inside vacuum chamber 22.

[0052] The carrier support unit 17 (substrate support mechanism) functions as a support to support the carrier 11 that is conveyed on the carrier transfer roller 20. The mask 12 is, for example, a metal mask, having an opening pattern corresponding to the thin film pattern formed on the substrate. The mask support unit 16 functions as a support to support the mask 12 that is fed in by the mask transfer roller 21. In the structure of this embodiment, after the carrier 11 is positioned and supported on the mask 12, it is conveyed out on the mask transfer roller 21. It should be noted that in the case of a structure that does not use the carrier 11, a substrate support mechanism that directly supports the substrate can be used.

[0053] Figure 8 (b) shows an example of the structure of the mask 12 in this embodiment. The mask 12 is a structure in which a mask foil 12b with a thickness of about a few μm to tens of μm is welded and fixed on a frame-shaped mask frame 12a. The mask frame 12a supports the mask foil 12b in a stretched state along its surface direction so that the mask foil 12b does not flex. The mask foil 12b includes a junction for dividing the film-forming area of ​​the substrate. When the mask 12 is assembled on the glass substrate 10, the junction of the mask foil 12b is in close contact with the glass substrate 10, shielding the film-forming material. When using a glass substrate or a substrate on which a film made of resin such as polyimide is formed is used as the glass substrate 10, iron alloys can be used as the main materials for the mask frame 12a and the mask foil 12b, and nickel-containing iron alloys are preferred.

[0054] A carrier Z-lifting base 23, a carrier Z-lifting sliding member 24, and a carrier clamping Z-sliding member 25 are provided on the upper outer side of the vacuum chamber 22. Each actuator is composed of, for example, an electric motor and a ball screw, or an electric motor and a linear guide. An alignment stage 26 is also provided on the upper outer side of the vacuum chamber 22. The alignment stage 26 is connected to the carrier Z-lifting base 23 and drives the carrier support unit 17 along the XYθ direction.

[0055] The carrier Z-axis lifting slider 24 (moving mechanism) drives the carrier support unit 17 as a whole along the Z-axis direction to raise and lower it. As a result, the relative distance between the glass substrate 10 and the mask 12 changes in an intersecting direction (typically perpendicular to the plane of the film-forming surface of the glass substrate 10) that intersects the plane along the film-forming surface of the glass substrate 10. The carrier clamping Z-axis slider 25 drives the pressing tool of the carrier support unit 17 to drive the carrier clamping member 27 along the Z-axis, thereby holding the carrier.

[0056] (Discussion on the relative positional deviation between the glass substrate and the mask)

[0057] As mentioned earlier, a positional deviation occurs when the aligned carrier 11 and mask 12 come into contact. As a result, the glass substrate 10, which is fixed to the carrier, is misaligned with the mask, which can sometimes affect the alignment accuracy. The causes of this positional deviation can be contact deviation or mechanical issues with the alignment device 80. Contact deviation can be caused by contact between the carrier 11 and mask 12, or by contact between the glass substrate 10 and mask 12.

[0058] Positional deviations caused by contact include positional deviations caused when the carrier 11 is placed on the mask 12, and positional deviations caused when the large glass substrate 10 contacts and adheres to the mask 12 due to its deflection. These are also referred to as the contact component of positional deviation. This contact component tends to vary according to each individual glass substrate 10, carrier 11, and mask 12.

[0059] On the other hand, the positional deviation caused by mechanical reasons is an inherent positional deviation of the alignment device that occurs during the phase when the relative distance between the carrier 11 and the mask 12 approaches, also known as the optical axis deviation component of the positional deviation. This optical axis deviation component has a constant value for each alignment camera of the alignment device, with small individual differences for each glass substrate, each carrier, and each mask.

[0060] For example, even if the control unit moves the substrate vertically, but actually tilts it slightly from the vertical direction, the relative position of the substrate and the mask encountered at the alignment height will deviate when they are in close contact. Alternatively, if the optical axis of the camera and the Z-axis sliding member's movement (direction of movement) are slightly inconsistent as they descend in the Z-direction, even if alignment is determined to be complete at the alignment height, a deviation in relative position will occur when they are in close contact. It should be noted that the optical axis of the camera and the movement direction of the Z-axis sliding member do not need to be vertical. As long as they are consistent, positional deviation during control can be prevented.

[0061] In conventional methods, the positional deviation component caused by contact and the positional deviation component caused by optical axis deviation are not distinguished; instead, they are both reflected in the offset. Positional deviation caused by substrate contact varies from substrate to substrate due to uneven friction. Therefore, the accuracy of offset correction may decrease due to the influence of the substrate positional deviation component caused by contact, which has low reproducibility. Therefore, a method is required to calculate the mechanical component of positional deviation separately from the contact component. In particular, for high-precision correction of the mechanical component, high-precision measurement of the Z-direction height of the contact deviation caused by the final close contact between the glass substrate 10 and the mask 12 is necessary.

[0062] Therefore, in this application, in order to accurately correct the mechanical component of positional deviation, the method also includes measuring the height of the positional deviation caused by contact for offset correction during alignment. It should be noted that since the mechanical component of positional deviation is an inherent mechanical component of the alignment device 80, it can be calculated in advance by installing correction marks on a dedicated fixture, or it can be calculated during the alignment process. Furthermore, the offset correction of the mechanical component of positional deviation can be used in conjunction with the offset correction of positional deviation caused by contact, or it can be used alone.

[0063] return Figure 2 Continuing the explanation, the alignment stage 26 (alignment mechanism) moves the carrier 11 along the XY direction and rotates it along the θ direction, thereby changing the position of the carrier 11 and the mask 12. Specifically, the alignment stage 26 adjusts the relative position of the glass substrate 10 and the mask 12 in a plane along the film-forming surface of the glass substrate 10 held by the carrier. The alignment stage 26 includes a chamber fixing part 37 connected and fixed to the vacuum chamber 22, an actuator part 28 for XYθ movement, and a connecting part 29 connected to the carrier support unit.

[0064] It should be noted that the alignment stage 26, the carrier Z lifting slider 24, the carrier support unit 17, the carrier clamping member 27, the carrier 11, and the control unit 30 can be considered together as an alignment device 80 for aligning the glass substrate 10 and the mask 12. The alignment device 80 may also include cameras, which will be described later.

[0065] As actuator unit 28, an actuator formed by stacking X, Y, and θ actuators can be used. Furthermore, a UVW actuator with multiple actuators cooperating can also be used. Regardless of the type of actuator unit 28, it is driven according to the control signal sent from the control unit 30, causing the glass substrate 10 to move along the X and Y directions and rotate along the θ direction. For a stacked actuator, the control signal represents the actuation amount of each X, Y, and θ actuator; for a UVW actuator, the control signal represents the actuation amount of each UVW actuator.

[0066] The alignment stage 26 causes the carrier support unit 17 to move in the XYθ direction. It should be noted that in this embodiment, the structure is set to adjust the position of the carrier 11, but it can also be a structure to adjust the position of the mask 12, or a structure to adjust the positions of both the carrier 11 and the mask 12, as long as the glass substrate 10 and the mask 12 can be aligned relative to each other.

[0067] Multiple alignment cameras 31 (measuring mechanisms) are provided on the upper outer side of the vacuum chamber 22 to generate image data through optical imaging. The alignment cameras 31 take pictures through the sealed window 32 provided in the vacuum chamber 22 for maintaining vacuum.

[0068] Multiple alignment cameras 31 are positioned to capture images of the marks mounted at the corners of the glass substrate 10 and the mask 12. When the glass substrate 10 and the mask 12 are within the alignment height range, the camera capture area includes the substrate mark 13 on the surface of the glass substrate and the mask mark 14 on the surface of the mask.

[0069] Here, the configuration of substrate mark 13 and mask mark 14 will be described. Figure 8 (a) is a view of the glass substrate 10 from above. The outer edge of the carrier 11 supporting the glass substrate 10 is indicated by dashed lines. Substrate markings 13a to 13d are formed at the corners of the glass substrate 10. In this example, four alignment cameras 31a to 31d are arranged above the vacuum chamber. These alignment cameras 31a to 31d simultaneously photograph the substrate markings 13a to 13d.

[0070] Figure 8 (b) is a view of the mask 12 from above, showing mask marks 14a to 14d formed at the four corners of the mask frame 12a. The mask marks 14a to 14d are simultaneously photographed by the cameras 31a to 31d. It should be noted that the positions and number of the substrate mark 13, mask mark 14, and camera 31 are not limited to this example.

[0071] Figure 8 (c) shows the field of view 44 (shooting field of view) of a certain alignment camera 31 during the alignment process. In this example, the substrate mark 13 and the mask mark 14 are simultaneously photographed within the field of view 44, thus enabling the determination of the relative positions of the mark centers. It should be noted that the shapes of the substrate mark 13 and the mask mark 14 are not limited to the example shown in the figure, but symmetrical shapes are preferred for ease of calculating the center positions. It should be noted that it is preferable to set up a low-magnification camera with a wide field of view for general alignment and a high-magnification camera for high-precision alignment, performing two-stage alignment.

[0072] The control unit 30 obtains the relative positional relationship between the glass substrate 10 and the mask 12 in the planar direction from the captured image. Furthermore, based on feedback from this relative positional information, the control unit 30 controls the driving amount of the actuator unit 28 and other driving units until the substrate mark 13 and mask mark 14 within each field of view 44 are close to a predetermined positional relationship. In this way, the alignment device 80 aligns the glass substrate 10 and mask 12 on the carrier 11 in a plane parallel to the film-forming surface of the substrate. Then, the carrier Z lifting slider 24 is driven to place the carrier 11 (glass substrate 10) onto the mask 12.

[0073] During the movement of the carrier 11 within the XY plane, the alignment stage 26 is used to move the carrier support unit 17 supporting the carrier 11 by translation along the XY direction or rotation along the θ direction. Here, "within the plane" refers to the plane on which the mask 12 is disposed or a plane substantially parallel to the film-forming surface of the glass substrate 10. That is, during the XY movement and θ rotation of the glass substrate 10, the distance between the glass substrate 10 and the mask 12 in the Z direction remains unchanged, but the position of the glass substrate 10 changes within the XY plane.

[0074] (Structure of the clamp)

[0075] The above describes the alignment process of the glass substrate 10 and mask 12 in a typical film deposition process. Next, the structure of the characteristic fixture in this application and the correction mark 15 attached to the fixture will be described. The correction fixture 40 with the correction mark 15 can be installed on the carrier support unit 17 of the alignment device 80, which holds the carrier. Alternatively, the movable correction fixture 40 can be permanently positioned in the carrier support unit 17 beforehand. When measuring the correction mark, the movable fixture can be moved to a position where it can be photographed. During the normal alignment of the glass substrate 10 and mask 12, the movable fixture can be stored in a position that does not interfere with the alignment. Furthermore, the substrate mark 13 on the glass substrate 10 can also be used. However, when using the glass substrate 10, it is necessary to avoid contact between the glass substrate 10 and the mask 12 when calculating the correction value.

[0076] Figure 9 This is a top view of the correction fixtures 40 (40a-40d). The line corresponding to the outer edge of the carrier 11 is represented by a single-dotted line 11f. It should be noted that the carrier support unit 17 does not simultaneously support both the carrier 11 and the correction fixtures 40; therefore, the single-dotted line 11f is a virtual outer edge line. In this embodiment, there are four correction fixtures 40, each held by the carrier support unit 17 at a position corresponding to one of the four corners of the carrier 11. As a result, the correction marks 15a-15d are housed within the field of view 44a-44d of the aligned cameras 31a-31d.

[0077] The dimensions of the correction fixture 40 in the XY plane need to be increased to at least accommodate the correction mark 15 within the field of view. Furthermore, if the correction fixture 40 is too large, it may partially deflect and potentially contact the mask 12; therefore, the degree of deflection is set to be negligible. Alternatively, to reduce deflection itself, a method can be considered that ensures rigidity by managing the thickness and second moment of the section of the correction fixture, thereby reducing deflection and preventing contact.

[0078] The control unit 30 is a control mechanism that analyzes the image data captured by the alignment camera 31, detects the substrate mark 13, mask mark 14, and correction mark 15, and obtains the coordinates of the marks in the XYZ coordinate system of the device as position information. Based on the positional deviation of the alignment marks between the substrate and the mask, the control unit 30 calculates the XY direction, distance, and angle θ that move the carrier 11. Then, it converts the calculated movement amount into the drive amount of the stepper motor, servo motor, etc., of each actuator of the alignment stage 26, and generates a control signal.

[0079] In this embodiment, the alignment camera 31 captures images at multiple substrate heights, as detailed below. Specifically, the multiple substrate heights in this embodiment are the alignment height (first height) and the contact height between the carrier and the mask (second height). However, the second height only needs to be close to the height of the mask 12 compared to the first height, and it is not necessary for the carrier to contact the mask. It should be noted that "substrate height" refers to the distance between the mask 12 and the glass substrate 10 in the direction of intersection when the height of the mask 12 when it contacts the glass substrate 10 is set to 0, and the distance between the mask 12 and the glass substrate 10 in the direction of intersection with the surface of the mask 12 (or the film-forming surface of the glass substrate 10). In other words, in the direction of intersection with the film-forming surface of the glass substrate 10 (typically the direction perpendicular to the film-forming surface), two images are captured: one when the carrier 11 is at the alignment height and the other when the carrier is at the contact height with the mask. Furthermore, position information (marked coordinate information, first position information) at the alignment height and position information (second position information) at the contact height between the carrier and the mask are obtained. In this embodiment, the shooting is set to be taken at two different heights, but the shooting height and the number of shots are not limited to this example.

[0080] Here, the information obtained at the alignment height and contact height is the coordinates of substrate mark 13 and mask mark 14 under normal alignment conditions. Moreover, when the calibration fixture 40 is used for measurement, it is the coordinates of calibration mark 15 and mask mark 14.

[0081] The control unit 30 also performs various other controls, such as alignment control based on the motion control of each actuator in the actuator unit 28, feeding and feeding control of the carrier 11 and mask 12, and motion control of the carrier Z lifting slider. The control unit 30 can be configured as a computer, for example, equipped with a processor, memory, storage, and I / O. In this case, the functions of the control unit 30 are implemented by the processor executing programs stored in the memory or storage of the storage unit 34. As the computer, a general-purpose personal computer, an embedded computer, or a PLC (programmable logic controller) can be used. Alternatively, some or all of the functions of the control unit 30 can be configured using circuits such as ASICs or FPGAs. It should be noted that the control unit 30 can be set up for each alignment device 80, or one control unit 30 can control multiple alignment devices 80. The calculation of various alignment offset corrections is also performed by the control unit 30.

[0082] The storage unit 34 is the storage mechanism for the executable program and data used by the storage control unit 30. Any storage mechanism such as flash memory, non-volatile memory, SSD, or HDD can be used. The control unit 30 pre-stores the calculated offset in the storage unit 34 and uses it for offset correction during the alignment process.

[0083] Next, details of the carrier support unit 17 of the alignment device 80 will be explained. Figure 3 It is a cross-sectional view showing the enlarged holding part of the carrier 11 and the mask 12. Figure 3 (a) shows the case where the carrier 11 holding the glass substrate 10 is supported. Figure 3 (b) shows the case where the correction fixture 40 of the present invention with correction mark 15 is supported.

[0084] The carrier support unit 17 includes a carrier receiving claw 41 protruding from the support portion along the XY plane, a carrier receiving surface 42 disposed on the upper surface of the carrier receiving claw 41, and a carrier clamping member 27. With the carrier 11 placed and supported on the carrier receiving surface 42, the carrier clamping member 27 is pressed down from above to clamp it, thereby fixing the carrier 11 in a supported state. In this state, the alignment stage 26 is driven, thereby aligning the glass substrate 10 relative to the mask 12.

[0085] After the mask 12 is fed into the vacuum chamber in a position placed on the mask transfer roller 21, it is delivered from the mask transfer roller 21 to the mask support unit 16. The mask support unit 16 has a mask lifting mechanism that allows the mask 12 to move up and down in the Z direction. The alignment described above is performed with the mask 12 delivered and supported on the mask support unit 16. Using the mask support unit 16 is preferred in terms of suppressing the effects of vibration from each transfer roller and achieving high alignment accuracy. However, alignment can also be performed on the mask transfer roller 21 without using the mask support unit 16.

[0086] (Obtaining the correction value)

[0087] Next, use Figure 6 , Figure 7 This describes the method for obtaining the correction value and the correction method of the present invention. Figure 6 This diagram illustrates the state of the correction mark 15 (represented by the circular symbol "〇") and the mask mark 14 (represented by the square symbol "□") captured within the camera's field of view 44 by aligning the camera 31. The solid circular symbol "〇" indicates the positional relationship of the correction mark 15 at the aligned height, represented by coordinates (X, Y) in the camera coordinate system. For simplicity, the reference (0, 0) is set as the center coordinate of the mask mark 14. The height of the carrier Z lifting slider 24 is set as ha at this time.

[0088] Furthermore, in order to determine the relative tilt between the direction of travel of the carrier Z lifting slider 24 and the direction of the camera optical axis 33, the coordinates of the correction mark 15 when the carrier Z lifting slider 24 descends are measured. The lower end during descent is set at the height at which the carrier 11 rests on the mask 12, and this height is set as h0. At this time, the coordinates of the correction mark 15 (represented by the dashed circle 15') change to (X', Y').

[0089] Figure 7 The X-direction change of the carrier Z lifting slider 24 is shown when it descends from ha to h0.

[0090] The change in the X direction at this time is

[0091] XX′=δx.

[0092] Furthermore, the change in the Y direction can also be calculated in the same way.

[0093] YY′=δy.

[0094] In this way, based on the image processing results of the alignment height and the contact height, the relative positional change of the mask mark 14 and the correction mark 15 can be calculated.

[0095] This calculated value can be used as an offset correction value in the XY direction during alignment. That is, by pre-offsetting the substrate mark 13 at the alignment height to a state that is offset from the mask mark 14 by (-δx, -δy), the substrate mark 13 and the mask mark 14 are aligned at the contact height.

[0096] Furthermore, when the camera 31 has a pitch mechanism, optical axis correction can be performed by calculating the relative tilt of the carrier Z lifting slider 24 to the camera optical axis 33 based on the aforementioned correction value. That is, if the relative tilt is taken as X, the optical axis correction is obtained...

[0097] θx = atan(δx / (ha-h0)),

[0098] As Y is relatively tilted,

[0099] θy=atan(δy / (ha-h0))

[0100] By tilting the camera 31, the relative tilt can be reduced, thus reducing the offset during descent.

[0101] It should be noted that as long as the direction of travel of the carrier Z lifting slider 24 is aligned with the optical axis of the camera 31, the relative positions of the marks within the field of view can be made consistent at the alignment height ha and the contact height h0. Therefore, the direction of travel of the carrier Z lifting slider 24 can be corrected instead of the pitch correction of the optical axis. During correction, it is not necessary to set the aforementioned direction of travel and optical axis as vertical.

[0102] It should be noted that the above method is defined under the premise that the tilt of the optical axis during the descent from ha to h0 is linear. However, considering the case where the tilt is not necessarily linear, we can... Figure 7 The correction value is measured at each height along the Z direction with a fine scribbling width, and the correction value is derived by approximate calculation using the least squares method, etc. Moreover, the discrete measured values ​​at each height can be reflected as correction values ​​without using approximation formulas.

[0103] Furthermore, the coordinates (X, Y) of the aforementioned correction mark 15 are based on the mask mark 14. However, even without the mask mark 14, the correction value can be obtained by taking any origin of the camera coordinate system as a reference and obtaining the position change of the correction mark in the XY direction from the origin when moving to various heights ha and h0.

[0104] (Processing flow)

[0105] Next, regarding the sequence of steps for obtaining the alignment correction value using the present invention, refer to... Figure 4This process uses a dedicated fixture and is preferably performed separately from the usual film formation process, during setup, maintenance, or other times when the alignment device is being used.

[0106] First, install the correction clamp 40 with the correction mark 15 on the carrier support unit 17. Alternatively, pull the correction clamp 40 out from its storage position. (Step S1)

[0107] Next, the correction mark 15 is moved in a manner aligned with the center of the camera. The carrier Z lifting slider 24 is driven up and down (step S2).

[0108] Next, at each measurement height required for the alignment sequence, images are taken using the alignment camera 31, and the position of the correction mark 15 is determined based on the obtained images (step S3). The "required measurement heights" mentioned here include the height at which the carrier 11 does not contact the mask 12 even during XYθ driving. Preferably, the range of these measurement heights includes... Figure 7 The actual alignment height *ha* shown is the actual alignment height, and the contact height *h0* is the height at which the carrier 11 contacts the mask 12 and is seated after alignment is completed. This eliminates the influence of mechanical deviation caused by the contact between the carrier 11 and the mask 12, allowing the alignment device to accurately measure and correct for the influence of the relative movement of the lifting slider 24 and the relative tilt of the camera optical axis 33. As a result, alignment accuracy is improved. However, correction values ​​at unmeasured heights can also be calculated through interpolation, extrapolation, or other interpolation processes.

[0109] If the required positional information for measuring height is not fully obtained, return to step S2 to change the height of the correction fixture 40 and take a picture (step S4).

[0110] Furthermore, the control unit 30 performs correction value calculations based on the obtained position information and stores the results in the storage unit 34. (Step S5)

[0111] The positional deviation caused by the optical axis deviation is based on the inherent positional deviation of the device aligning the camera 31 and the carrier Z lifting slider 24. Therefore, if a correction value has already been obtained, it is not necessary to obtain data again unless a situation arises where the optical axis direction or the direction of the slider travels changes due to a malfunction of the device.

[0112] It should be noted that a correction fixture 40 was used in the above process, but a conventional carrier 11 and glass substrate 10 can also be used, replacing the correction mark 15 with a substrate mark 13. In this case, when taking pictures to obtain the correction value, especially at the contact height, it is necessary to avoid contact between the glass substrate 10 and the carrier 11 and the mask 12 to avoid contact deviation components.

[0113] Next, regarding the alignment process that uses correction values, please refer to... Figure 5 Please provide an explanation.

[0114] First, a carrier 11 holding a glass substrate 10 and a mask 12 are separately fed from the mask assembly chamber 103 into the alignment chamber 104 (step S10). At this time, the carrier 11 is conveyed on the carrier conveying roller 20, and the mask 12 is conveyed on the mask conveying roller 21.

[0115] Next, the carrier 11 is delivered from the carrier transfer roller 20 to the carrier support unit 17 by raising the carrier support unit 17 in the Z direction (step S11).

[0116] Additionally, the mask 12 is delivered from the mask transfer roller 21 to the mask support unit 16 by raising the mask support unit 16 (step S12).

[0117] Next, the carrier conveying roller 20 is retracted, and the carrier support unit 17 is lowered in the Z direction to move the carrier 11 to the alignment height (step S13).

[0118] Next, the alignment position is confirmed by taking pictures of the substrate mark 13 on the glass substrate 10 and the mask mark 14 on the mask 12 with the camera 31 (step S14).

[0119] Apply the target position to the alignment position via Figure 4 The correction value is calculated using the process. If the alignment position is within the target value, then proceed to step S17 (step S15). For example, the amount of movement of the substrate mark 13 with the mask mark 14 as the reference (0, 0) during the movement of the carrier 11 from the alignment height ha to the contact height h0 is set as (δx, δy). Moreover, the coordinates of the substrate mark 13 obtained in the image captured at the alignment height ha are set as (x, y). In this case, if the correction amount is applied as the offset value (x-δx, y-δy) and the distance from the reference (0, 0) is within the specified target value range, then proceed to step S17. It should be noted that if the pitch correction of the optical axis has already been performed using the correction value, such offset correction is not required, and only the normal alignment process needs to be performed.

[0120] On the other hand, if the value is not within the target range, return to step S14 and move the alignment stage 26 along the XYθ direction to perform another shot based on the alignment camera (step S16).

[0121] If the target value is within the acceptable range, the carrier support unit 17 is lowered along the Z direction to place the carrier 11 on the mask 12 (step S17). Then, the alignment position is confirmed by taking a picture with the alignment camera 31 (step S18). If the alignment position is not within the target value, the process returns to step S13 and the carrier support unit 17 is raised along the Z direction.

[0122] On the other hand, if the alignment position is within the target value, proceed to step S20 (step S19). Then, the mask support unit 16 is lowered along the Z direction to deliver the mask 12 to the mask transfer roller 21 and send it out to the film forming chamber 105 (step S20).

[0123] As described above, in this invention, a dedicated fixture with correction marks is used to obtain the positional deviation between the substrate and the mask as a correction value. Because this fixture is smaller than the substrate and has less deflection, even at a height where the deflected portion of the substrate would contact the mask, no contact deviation occurs. Therefore, the influence of the contact deviation component, which is a cause of positional deviation, can be eliminated, and only the influence of mechanical components such as optical axis deviation and the deviation in the travel direction of the Z-axis lifting slider is measured.

[0124] As a result, it is possible to accurately grasp the positional deviation caused by mechanical components and use it in various corrections such as offset correction, optical axis pitch correction, and Z-axis sliding component travel direction correction. Therefore, compared to the past, it enables high-precision alignment and excellent film formation.

[0125] <Example 2>

[0126] (Manufacturing methods for organic electronic devices)

[0127] In this embodiment, an example of a method for manufacturing an organic electronic device using a film-forming apparatus equipped with an alignment device is described. Hereinafter, the structure and manufacturing method of an organic EL display device are illustrated as examples of organic electronic devices. First, the manufactured organic EL display device will be described. Figure 10 (a) is an overall view of the organic EL display device 60. Figure 10 (b) represents the cross-sectional structure of a pixel.

[0128] like Figure 10As shown in (a), multiple pixels 62, each equipped with a plurality of light-emitting elements, are arranged in a matrix in the display area 61 of the organic EL display device 60. Each light-emitting element has a structure having an organic layer held by a pair of electrodes. It should be noted that, as used here, a pixel refers to the smallest unit capable of displaying a desired color in the display area 61. In the case of the organic EL display device of this figure, the pixel 62 is constructed by a combination of a first light-emitting element 62R, a second light-emitting element 62G, and a third light-emitting element 62B that exhibit different light emission. The pixel 62 is mostly composed of a combination of red, green, and blue light-emitting elements, but it can also be a combination of yellow, cyan, and white light-emitting elements, as long as there is at least one color, there is no particular limitation.

[0129] Figure 10 (b) is Figure 10 A partial cross-sectional view of line AB in (a). Pixel 62 has an organic EL element, which has a first electrode (anode) 64, a hole transport layer 65, any one of light-emitting layers 66R, 66G, and 66B, an electron transport layer 67, and a second electrode (cathode) 68 on the substrate 10. The hole transport layer 65, the light-emitting layers 66R, 66G, 66B, and the electron transport layer 67 are equivalent to organic layers. Moreover, in this embodiment, the light-emitting layer 66R is a red-emitting organic EL layer, the light-emitting layer 66G is a green-emitting organic EL layer, and the light-emitting layer 66B is a blue-emitting organic EL layer.

[0130] The light-emitting layers 66R, 66G, and 66B are respectively formed in patterns corresponding to the red, green, and blue light-emitting elements (sometimes referred to as organic EL elements). Furthermore, the first electrode 64 is formed separately for each light-emitting element. The hole transport layer 65, electron transport layer 67, and second electrode 68 can be formed shared with multiple light-emitting elements 62R, 62G, and 62B, or they can be formed separately for each light-emitting element. It should be noted that an insulating layer 69 is provided between the first electrode 64 and the second electrode 68 to prevent short circuits due to impurities. In addition, since the organic EL layer deteriorates due to moisture or oxygen, a protective layer P is provided to protect the organic EL element from moisture or oxygen.

[0131] Next, an example of a method for manufacturing an organic EL display device as an electronic device will be specifically described. First, a substrate 10 is prepared, which has a circuit (not shown) for driving the organic EL display device and a first electrode 64.

[0132] Next, acrylic resin is spin-coated onto the substrate 10 where the first electrode 64 is formed. The acrylic resin is then patterned using photolithography to form an opening in the portion where the first electrode 64 is formed, thus forming an insulating layer 69. This opening corresponds to the light-emitting area where the light-emitting element actually emits light.

[0133] Next, the substrate 10, patterned with the insulating layer 69, is fed into the first film-forming apparatus. The substrate is supported by a substrate support unit, and the hole transport layer 65 is formed as a common layer on the first electrode 64 of the display area. The hole transport layer 65 is formed by vacuum evaporation. In practice, the hole transport layer 65 is formed to a size larger than the display area 61, therefore a high-precision mask is not required. Here, the film-forming apparatus used in this step and in the subsequent layer formations is any of the film-forming apparatuses described in the above embodiments.

[0134] Next, the substrate 10, with the hole transport layer 65 formed thereon, is fed into the second film deposition apparatus and supported by the substrate support unit. Alignment is performed between the substrate and the mask, and the substrate is placed on the mask. A red-emitting light-emitting layer 66R is formed on the portion of the substrate 10 where the red element is positioned. According to this example, the mask and substrate can be well aligned, enabling high-precision film deposition.

[0135] Similar to the deposition of the light-emitting layer 66R, a green light-emitting layer 66G is deposited using the third film-forming apparatus, and a blue light-emitting layer 66B is deposited using the fourth film-forming apparatus. After the deposition of the light-emitting layers 66R, 66G, and 66B is completed, an electron transport layer 67 is deposited over the entire display area 61 using the fifth film-forming apparatus. The electron transport layer 67 is formed as a shared layer among the three-color light-emitting layers 66R, 66G, and 66B.

[0136] The substrate with the electron transport layer 67 formed is moved to the sputtering device to form the second electrode 68, and then moved to the plasma CVD device to form the protective layer P, thus completing the organic EL display device 60.

[0137] From the moment the substrate 10 with the insulating layer 69 is fed into the film-forming apparatus until the film formation of the protective layer P is completed, if exposed to an atmosphere containing moisture or oxygen, the light-emitting layer made of organic EL material may deteriorate due to moisture or oxygen. Therefore, in this example, the feeding and unloading of the substrate between the film-forming apparatuses is performed under a vacuum atmosphere or an inactive gas atmosphere.

[0138] According to the manufacturing method of the alignment device, film-forming device, or electronic device of this embodiment, it is possible to form a good film with improved alignment accuracy.

Claims

1. An alignment device characterized by comprising: an alignment mechanism that adjusts a relative position of a substrate and a mask in a plane along a film formation surface of the substrate; a moving mechanism that moves the relative position of the substrate with respect to the mask in a cross direction intersecting the plane; a measuring mechanism that measures a position of the substrate in the plane; and a substrate support mechanism that supports the substrate, the substrate support mechanism being capable of supporting a jig instead of the substrate, the jig having a smaller amount of deflection than the substrate, the measuring mechanism measuring first position information of a correction mark held by the jig in a state where the jig is arranged at a first height, the measuring mechanism measuring second position information of the correction mark in a state where the jig is arranged at a second height closer to the mask than the first height, and a correction value for the relative position adjustment is calculated using the first position information and the second position information in order to adjust an optical axis of a camera held by the measuring mechanism or a shaft of the moving mechanism.

2. The alignment device according to claim 1, characterized in that the substrate support mechanism is provided with the movable jig.

3. The alignment device according to claim 1, characterized in that the measuring mechanism is a mechanism that measures a substrate mark held by the substrate and a mask mark held by the mask, and the correction mark is attached to a position in the jig corresponding to the substrate mark.

4. The alignment device according to claim 2, characterized in that the measuring mechanism is a mechanism that measures a substrate mark held by the substrate and a mask mark held by the mask, and the correction mark is attached to a position in the jig corresponding to the substrate mark.

5. The alignment device according to any one of claims 1 to 4, characterized in that the first height is a height of the substrate when the relative position adjustment is performed.

6. A film formation device characterized by comprising: the alignment device according to any one of claims 1 to 5; and a film formation source that performs film formation on the substrate via the mask, the film formation device being characterized in that the second height is a height when the film formation is performed.

7. A film formation device characterized by comprising a plurality of chambers including a chamber in which the alignment device according to any one of claims 1 to 5 is arranged, in a series. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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