Alignment apparatus, alignment method, film forming apparatus, and manufacturing method

Abstract

The invention relates to an alignment device, an alignment method, a film forming device and a manufacturing method which facilitate detection of marks respectively arranged on a substrate and a mask. The alignment device is used for aligning a substrate and a mask for forming a pattern on a film formation surface of the substrate, and is characterized in that the alignment device is provided with a camera, the camera is arranged on the opposite side of the mask in a state that the substrate and the mask are overlapped, the camera detects a first mark and a second mark, and the first mark and the second mark are arranged on the opposite side of the mask. The first mark is arranged on the back face of the side, opposite to the film forming face, of the substrate, the second mark is arranged on the mask, the mask comprises a pattern part, the pattern part comprises an opening used for forming the pattern, and the first mark is arranged on the back face of the side, opposite to the film forming face, of the substrate. And a protruding portion that protrudes from an outer edge portion of an opposing surface of the pattern portion that faces the film formation surface to a side on which the substrate is overlapped, and the camera detects the second mark provided on an upper surface of the protruding portion.

Description

Technical Field

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

[0002] Organic EL display devices (OLEDs) are used not only in smartphones, televisions, and automobile displays, but also in VR HMDs (Virtual Reality Head Mount Displays). In the process of manufacturing an organic EL display device, a film forming device is generally used when an organic light-emitting element (OLED) is formed on a substrate.

[0003] The film forming device forms an organic film, a metal film, etc. by attaching the evaporated material (film forming material) emitted from the evaporation source to the substrate via a mask having a pattern corresponding to the pixel pattern. At this time, the substrate and the mask need to be aligned with high precision.

[0004] A technique related to the alignment of a substrate and a mask has been proposed (see Patent Document 1). Patent Document 1 discloses a technique in which a camera provided on the side opposite to the mask with respect to the substrate is used to measure the relative position (positional offset) of marks provided on the substrate and the mask, respectively, and the position of at least one of the substrate and the mask is adjusted based on the measurement result.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2017 / 222009

[0008] The camera used in the alignment of the substrate and the mask generally illuminates the mark with measurement light such as visible light, detects (observes) the measurement light (reflected light) reflected by the mark, and thereby optically measures the position of the mark set on the substrate or mask. Therefore, when the transmittance of the substrate or mask is low relative to the measurement light used in the camera, the amount of measurement light (reflected light from the mark) detected by the camera decreases, and the measurement accuracy of the position of the mark set on the substrate or mask decreases. In addition, depending on the transmittance of the substrate or mask with respect to the measurement light, it becomes difficult to measure the position of the mark set on the substrate or mask. Summary of the invention

[0009] Problems to be solved by the invention

[0010] The present invention provides a technique that is useful for detecting marks disposed on a substrate and a mask, respectively.

[0011] Means for solving problems

[0012] As one aspect of the present invention, an alignment device is used for aligning a substrate and a mask, wherein the mask is used to form a pattern on the film-forming surface of the substrate, and is characterized in that it has a camera, which is arranged on the side opposite to the mask when the substrate and the mask overlap, and detects a first mark and a second mark, wherein the first mark is arranged on the back side of the substrate on the side opposite to the film-forming surface, and the second mark is arranged on the mask, and the mask comprises: a pattern portion, wherein the pattern portion comprises an opening for forming the pattern; and a protrusion, wherein the protrusion protrudes from the outer edge portion of the opposite surface of the pattern portion facing the film-forming surface toward the side on which the substrate overlaps, and the camera detects the second mark arranged on the upper surface of the protrusion.

[0013] As another aspect of the present invention, an alignment method for aligning a substrate and a mask, wherein the mask is used to form a pattern on a film-forming surface of the substrate, is characterized in that it comprises: a process of detecting a first mark provided on the substrate and a second mark provided on the mask using the above-mentioned alignment device; and a process of aligning the substrate and the mask based on the result of detecting the first mark and the second mark.

[0014] A film forming apparatus according to still another aspect of the present invention forms a film on a substrate via a mask, and is characterized by comprising the above-mentioned alignment apparatus for aligning the substrate and the mask.

[0015] A production method as still another aspect of the present invention is characterized in that an electronic device is produced using the above-mentioned film-forming apparatus.

[0016] Further objects and other aspects of the present invention will become apparent from the following embodiments described with reference to the accompanying drawings.

[0017] Effects of the Invention

[0018] According to the present invention, for example, a technique useful for detecting marks provided on a substrate and a mask can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a diagram schematically showing the structure of a production line of a film forming apparatus to which one aspect of the present invention can be applied.

[0020] Figure 2 This is a diagram schematically showing the structure of a film forming apparatus as one aspect of the present invention.

[0021] Figure 3 The diagram is an enlarged view of a substrate, a mask, a substrate holding portion, and the vicinity of a mask holding portion.

[0022] Figure 4 The diagram is an enlarged view of a substrate, a mask, a substrate holding portion, and the vicinity of a mask holding portion.

[0023] Figure 5 (A) and (B) are diagrams schematically showing the structure of a camera.

[0024] Figure 6 (A) and (B) are diagrams for explaining an organic EL display device as an electronic device.

[0025] Description of Reference Numerals

[0026] 1: film forming device, 8: alignment device, 101: substrate, 101A: film forming surface, 101B: back surface, 102: mask, 102A: facing surface, 102C: pattern part, 102D: protrusion, 102E: upper surface, CR: camera, M1: first mark, M2: second mark DETAILED DESCRIPTION

[0027] The following detailed description of the embodiments is given with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the invention involved in the claims. In addition, all combinations of features described in the embodiments are not limited to the combinations required by the invention. Two or more of the multiple features described in the embodiments may also be arbitrarily combined. In addition, the same or similar structures are marked with the same figure numerals, and repeated descriptions are omitted.

[0028] Figure 1 1 is a diagram schematically showing the structure (layout) of a production line 100 of a film forming device to which the present invention can be applied as one aspect. The production line 100 includes a system for performing film forming processing on a substrate carried in and carrying out the substrate after the film forming processing, for example, a production line for electronic devices. It should be noted that in the following figures, arrow Z indicates the up-down direction (vertical (gravity) direction), and arrows X and Y indicate mutually orthogonal horizontal directions.

[0029] Production line 100 (film forming device) is particularly suitable as a production line for manufacturing organic light-emitting elements such as OLEDs, organic photoelectric conversion elements such as organic thin-film solar cells. As electronic devices, for example, light-emitting elements, photoelectric conversion elements, touch panels, etc. can be listed. In this embodiment, the electronic device includes a display device with a light-emitting element (such as an organic EL display device), a lighting device (such as an organic EL lighting device), a sensor with a photoelectric conversion element (such as an organic COMS image sensor), etc.

[0030] In the present embodiment, the production line 100 is embodied as a production line for manufacturing a display panel of an organic EL display device for a smartphone, or a display panel of an organic EL display device for a VR HMD. In the case of manufacturing a display panel for a smartphone, a 4.5th generation substrate (about 700 mm × about 900 mm), a 6th generation full-size substrate (about 1500 mm × about 1850 mm) or a half-cut size substrate (about 1500 mm × about 925 mm) is used. Film formation for forming an organic EL element is performed on such a substrate, and the substrate is cut to manufacture a plurality of small-sized panels. In addition, in the case of manufacturing a display panel for a VR HMD, a silicon wafer of a predetermined size (for example, 300 mm) is used. Film formation for forming an organic EL element is performed on such a silicon wafer, and a plurality of small-sized panels are manufactured by cutting the silicon wafer along the area (scribe area) between the element formation areas. However, the size and type of the substrate are not particularly limited and can be set appropriately.

[0031] like Figure 1 As shown, the production line 100 has an octagonal conveying chamber 120 in a plan view. The substrate 101 to be subjected to film forming is carried into the conveying chamber 120 via a conveying path 110 (carrying-in path). Also, the substrate 101 to be subjected to film forming is carried out from the conveying chamber 120 to a conveying path 111 (carrying-out path).

[0032] A plurality of film forming apparatuses 1 for performing film forming processing on substrates 101 are arranged around the transfer chamber 120. Transfer chambers 130 having an octagonal shape in plan view are arranged adjacent to the film forming apparatuses 1. A storage chamber 140 for storing masks 102 is arranged around the transfer chamber 130.

[0033] The conveying chamber 120 is provided with a conveying unit 121 for conveying the substrate 101. In the present embodiment, the conveying unit 121 includes a horizontal multi-joint robot, which holds and conveys the substrate 101 in a horizontal posture. The conveying unit 121 carries out a carrying operation of carrying the substrate 101 to be subjected to film forming process from the conveying path 110 into the film forming device 1, and carries out a carrying operation of carrying the substrate 101 to be subjected to film forming process from the film forming device 1 into the conveying path 111.

[0034] The transport chambers 130 are provided with transport units 131 for transporting the mask 102. In the present embodiment, the transport unit 131 includes a horizontal multi-joint robot that holds and transports the mask 102 in a horizontal posture. The transport unit 131 performs an action of transporting the mask 102 from the storage chamber 140 to the film forming apparatus 1 and an action of transporting the mask 102 from the film forming apparatus 1 to the storage chamber 140.

[0035] Figure 21 is a diagram schematically showing the structure of a film forming device 1 as one aspect of the present invention. The film forming device 1 performs a film forming process of attaching (evaporating) a vapor deposition material to a substrate 101 to form a film. In this embodiment, the film is formed on the substrate 101 via a mask 102. Specifically, the film forming device 1 forms a thin film of the vapor deposition material in a predetermined pattern relative to the film forming surface 101A of the substrate 101 via the mask 102. As the material of the substrate 101, glass, resin, metal, etc. can be appropriately selected. In particular, in this embodiment, the substrate 101 includes, for example, a glass substrate on which a TFT (Thin Film Transistor) is formed, and a silicon wafer on which a semiconductor element is formed. The mask 102 is composed of a magnetic body such as a metal. As the vapor deposition material, an organic material, an inorganic material (such as a metal, a metal oxide), etc. are used. Here, an example in which the film forming device 1 performs a film forming process on the substrate 101 by vacuum evaporation is described, but it is not limited to this, and various film forming processes (film forming methods) such as sputtering and CVD can be applied.

[0036] The film forming apparatus 1 includes a box-shaped vacuum chamber 2. The inner space of the vacuum chamber 2 is maintained in a vacuum atmosphere or an inert gas atmosphere such as nitrogen. In the present embodiment, the vacuum chamber 2 is connected to a vacuum pump (not shown) to maintain the inner space thereof in a vacuum atmosphere.

[0037] The evaporation unit 10 is provided in the internal space of the vacuum chamber 2. The evaporation unit 10 includes an evaporation source that releases the evaporation material upward. A gate 10a for limiting the release of the evaporation material from the evaporation source and releasing the limitation is provided above the evaporation unit 10. The gate 10a is opened and closed by an opening and closing mechanism (not shown). Figure 2 The shutter 10a is closed to limit the release of the vapor deposition material from the vapor deposition unit 10. An anti-adhesion plate 2a is also provided above the vapor deposition unit 10. The anti-adhesion plate 2a has a function of suppressing (preventing) the vapor deposition material released from the vapor deposition unit 10 from being unnecessarily attached to the structure provided in the upper part of the internal space of the vacuum chamber 2.

[0038] A substrate holding portion 3 for holding the substrate 101 in a horizontal position is provided in the internal space of the vacuum chamber 2. The substrate holding portion 3 is arranged on the side opposite to the mask 102 in the internal space of the vacuum chamber 2. In the present embodiment, the substrate holding portion 3 is configured as an electrostatic suction cup (first electrostatic suction cup) for adsorbing and holding the substrate S by electrostatic force. Specifically, the substrate holding portion 3 holds the substrate 101 with the film forming surface 101A of the substrate 101 facing downward (-Z direction) by adsorbing the back surface 101B of the substrate 101 on the side opposite to the film forming surface 101A. It should be noted that a cooling plate (not shown) including a water cooling mechanism or the like may also be provided in the substrate holding portion 3, for example. The cooling plate cools the substrate 101 via the substrate holding portion 3 during the film forming process.

[0039] The substrate holding portion 3 (and the cooling plate) is supported (suspended) by the magnet plate 5 via a support portion (not shown). The magnet plate 5 is a plate that causes a magnetic force to act on the mask 102 to attract the mask 102. The substrate 101 is sandwiched between the magnet plate 5 and the mask 102 attracted by the magnet plate 5 during the film forming process. The magnet plate 5 is provided to bring the substrate 101 and the mask 102 close to each other or to bring the substrate 101 and the mask 102 into close contact (improve the close contact).

[0040] The film forming device 1 has a mask holding mechanism 6 for holding a mask 102. The mask holding mechanism 6 includes a mask holding portion 6a for holding the mask 102 in a horizontal posture and an actuator 6b. The mask holding portion 6a is arranged on the back side 101B of the substrate 101 held by the substrate holding portion 3 in the internal space of the vacuum chamber 2 in a manner surrounding the substrate holding portion 3. In the present embodiment, the mask holding portion 6a is configured as an electrostatic suction cup (second electrostatic suction cup) that uses electrostatic force to adsorb and hold the mask 102. It should be noted that the specific structure of the mask holding portion 6a will be described in detail later. The actuator 6b includes, for example, an electric cylinder and an electric ball screw mechanism to raise and lower the mask holding portion 6a.

[0041] The film forming apparatus 1 includes an alignment device 8 for aligning the substrate 101 and the mask 102. The alignment device 8 includes a drive mechanism 80 and a plurality of cameras CR. The drive mechanism 80 includes a distance adjustment unit 81, a support shaft 82, a stage 83, and a position adjustment unit 84.

[0042] The distance adjustment unit 81 is a mechanism that includes, for example, an electric cylinder and an electric ball screw mechanism and moves the support shaft 82 up and down in the Z direction. The magnet plate 5 is supported (fixed) at the lower end of the support shaft 82. Therefore, the support shaft 82 is moved up and down by the distance adjustment unit 81, thereby moving the substrate holding part 3 up and down via the magnet plate 5. By moving the substrate holding part 3 up and down, the distance between the substrate 101 and the mask 102 in the up and down direction (Z direction) is adjusted, so that the substrate 101 and the mask 102 held in the substrate holding part 3 are brought close to or separated (separated). In other words, the distance adjustment unit 81 brings the substrate 101 and the mask 102 close to or separated in the overlapping direction (Z direction). It should be noted that the "distance" adjusted by the distance adjustment unit 81 is the so-called vertical distance (perpendicular distance). Therefore, the distance adjustment unit 81 can also be said to be a unit that adjusts the vertical position of the substrate 101 held in the substrate holding part 3. The distance adjustment unit 81 is mounted on the position adjustment unit 84 via the stand 83.

[0043] The position adjustment unit 84 adjusts the relative position of the substrate 101 with respect to the mask 102 in the XY plane by displacing (moving) the substrate holding portion 3 in the horizontal direction. In this way, the position adjustment unit 84 functions as a unit for adjusting the relative horizontal position of the substrate 101 and the mask 102. In the present embodiment, the position adjustment unit 84 displaces the substrate holding portion 3 in the X direction, the Y direction, and the rotation direction (θ direction) around the axis in the Z direction. It should be noted that in the present embodiment, the relative position of the substrate 101 and the mask 102 is adjusted by fixing the position of the mask 102 and displacing the substrate 101, but it is not limited to this. For example, the relative position of the substrate 101 and the mask 102 can also be adjusted by fixing the position of the substrate 101 and displacing the mask 102, or by displacing both the substrate 101 and the mask 102.

[0044] The position adjustment unit 84 includes a fixed plate 84a and a movable plate 84b. The fixed plate 84a and the movable plate 84b are rectangular frame-shaped plates. The fixed plate 84a is fixed to the upper wall portion 20 of the vacuum chamber 2. An actuator is provided between the fixed plate 84a and the movable plate 84b, and the actuator displaces the movable plate 84b relative to the fixed plate 84a in the X direction, the Y direction, and the rotation direction around the axis of the Z direction.

[0045] A frame-shaped stand 83 is placed on the movable plate 84b, and the stand 83 supports the distance adjustment unit 81. Therefore, when the movable plate 84b is displaced, the stand 83 and the distance adjustment unit 81 are displaced integrally, so that the substrate 101 held by the substrate holding part 3 can be displaced in the X direction, the Y direction, and the rotation direction around the axis in the Z direction. An opening portion for setting the support shaft 82 and the like is formed in the upper wall portion 20. The opening portion is sealed by a sealing member (not shown) such as a bellows to maintain the airtightness of the internal space of the vacuum chamber 2.

[0046] The camera CR is embodied as an imaging device that captures an image of a measurement object and functions as a measuring device that measures the position of the measurement object, for example. The camera CR is provided, for example, on the upper wall portion 20 of the vacuum chamber 2. In the present embodiment, the camera CR detects marks (alignment marks) provided on the substrate 101 and the mask 102 that are disposed in the internal space of the vacuum chamber 2, respectively, and measures the relative position (positional deviation) of the substrate 101 and the mask 102 based on their positions. In the alignment of the substrate 101 and the mask 102, the relative position of the substrate 101 and the mask 102 is adjusted via the position adjustment unit 84 so that the positional deviation of the substrate 101 and the mask 102 measured by the camera CR converges to an allowable range.

[0047] The film forming apparatus 1 has a control unit 9, which is composed of a computer (information processing device) and controls the entire film forming apparatus 1 by uniformly controlling the (actions of) the various components of the film forming apparatus 1. The control unit 9 includes a processing unit 90, a storage unit 91, an input / output (I / O) interface 92, and a communication unit 93. The processing unit 90 includes a processor represented by a CPU, and implements various actions and processes of the film forming apparatus 1 by executing programs stored in the storage unit 91. The storage unit 91 includes storage devices such as ROM, RAM, and HDD, which store programs executed by the processing unit 90 and various control information. The I / O interface 92 is an interface for communication (transmission and reception of various information and signals) between the processing unit 90 and external devices. The communication unit 93 is a communication device that communicates with a superior device, other control devices, etc. via a communication line.

[0048] Hereinafter, an example of control of the film forming apparatus 1 executed by the control unit 9 (processing unit 90 ) will be described, in which the substrate 101 is carried in, subjected to film forming processing, and then carried out.

[0049] First, the substrate 101 is moved into (the inner space of) the vacuum chamber 2. The substrate 101 is transported to the bottom of the substrate holding part 3 by the transport unit 121. The lower surface of the substrate holding part 3, that is, the adsorption surface 3a (the holding surface for holding the substrate 101) for adsorbing the back surface 101B of the substrate 101 is configured to be horizontal (flat). Then, the substrate 101 transported to the bottom of the substrate holding part 3 is moved to the substrate holding part 3. For example, by raising the transport unit 121 (driving in the +Z direction), the substrate 101 is pressed against the adsorption surface 3a of the substrate holding part 3. In this state, the function of the substrate holding part 3 as an electrostatic suction cup is activated, the back surface 101B of the substrate 101 is adsorbed by the adsorption surface 3a, and the substrate 101 is held by the substrate holding part 3.

[0050] Next, the mask 102 is moved into the vacuum chamber 2 (the internal space thereof). The mask 102 is transported from the storage chamber 140 to the vacuum chamber 2 by the transport unit 131, and is transported to the bottom of the mask holding part 6a and the bottom of the substrate 101 held by the substrate holding part 3. The lower surface of the mask holding part 6a, that is, the adsorption surface 61a (the holding surface for holding the mask 102) for adsorbing the facing surface 102A of the mask 102 is configured to be horizontal (flat). Here, the facing surface 102A of the mask 102 is the surface facing the film forming surface 101A of the substrate 101 held by the substrate holding part 3, and is the surface on the side opposite to the surface of the vapor deposition unit 10 (vapor deposition source). Then, the mask 102 located below the mask holding part 6a and the substrate 101 is moved to the mask holding part 6a. For example, by raising the transport unit 131 (driving in the +Z direction), the mask 102 is pressed against the adsorption surface 61a of the mask holding part 6a. In this state, the function of the mask holding part 6a as an electrostatic chuck is activated, and the facing surface 102A of the mask 102 is adsorbed by the adsorption surface 61a, and the mask 102 is held by the mask holding part 6a. In addition, the mask holding part 6a holding the mask 102 is further raised (driven in the +Z direction) by the actuator 6b, so that the mask 102 is located at the alignment position for aligning the substrate 101 and the mask 102.

[0051] Next, the substrate 101 held by the substrate holding portion 3 and the mask 102 held by the mask holding portion 6a are aligned. The alignment of the substrate 101 and the mask 102 is performed in a state where the substrate 101 and the mask 102 overlap. However, the state where the substrate 101 and the mask 102 overlap refers to a state where the substrate 101 and the mask 102 overlap when viewed from the Z direction, including both a state where the substrate 101 and the mask 102 are in physical contact and a state where they are not in physical contact. Therefore, in the alignment of the substrate 101 and the mask 102, a gap may be provided between the substrate 101 and the mask 102. In this way, in a state where the substrate 101 and the mask 102 overlap, the mark provided on the substrate 101 and the mark provided on the mask 102 are detected by the camera CR provided on the upper wall portion 20 of the vacuum chamber 2.

[0052] The camera CR illuminates the marks provided on the substrate 101 and the mask 102 respectively with visible light (measurement light), detects (observes) the light reflected by the marks (reflected light), and thereby optically measures the positions of the marks provided on the substrate 101 and the mask 102. Therefore, when the transmittance of the substrate 101 and the mask 102 is low relative to the visible light (measurement light) used in the camera CR, the amount of light detected by the camera CR is small, the measurement accuracy is reduced, or the measurement itself becomes difficult.

[0053] Therefore, in this embodiment, the substrate 101, the mask 102, the substrate holding portion 3, and the mask holding portion 6a are provided with a structure (structure) that facilitates detection of the marks provided on the substrate 101 and the mask 102 by the camera CR. Figure 3 and Figure 4 , a structure that is conducive to using the camera CR to detect the marks set on the substrate 101 and the mask 102 is specifically described. Figure 3 and Figure 4 The figure shows the vicinity of the substrate 101, the mask 102, the substrate holding portion 3, and the mask holding portion 6a in an enlarged manner. Figure 3 A cross-sectional view showing a substrate 101, a mask 102, a substrate holding portion 3, and a mask holding portion 6a, Figure 4 The top view shows the substrate 101, the mask 102, the substrate holding portion 3, and the mask holding portion 6a.

[0054] like Figure 3 and Figure 4 As shown, the substrate 101 is provided with a first mark M1 as a measurement target of the camera CR on its back side 101B. The first mark M1 is embodied as an alignment mark detected by the camera CR in the alignment between the substrate 101 and the mask 102. Therefore, the first mark M1 is provided on the back side 101B of the substrate 101 in such a manner as to be within the range of the field of view (detection range) of the camera CR provided on the upper wall portion 20 of the vacuum chamber 2. Thus, in the alignment between the substrate 101 and the mask 102, the first mark M1 provided on the back side 101B of the substrate 101 can be detected by the camera CR.

[0055] On the other hand, the mask 102 includes: a pattern portion 102C including an opening (not shown) for forming a pattern on the film forming surface 101A of the substrate 101; and a protrusion 102D provided around the pattern portion 102C. Figure 3 As shown, the protrusion 102D is a portion protruding from the outer edge OE of the facing surface 102A of the pattern portion 102C to the side (+Z direction) on which the substrate 101 is overlapped along the side surface 101C of the substrate 101. In addition, a second mark M2, which is a measurement object of the camera CR, is provided on the upper surface 102E of the protrusion 102D. The second mark M2 is embodied as an alignment mark detected by the camera CR in the alignment of the substrate 101 and the mask 102. Therefore, the second mark M2 is provided on the upper surface 102E of the protrusion 102D in a manner that is within the range of the field of view (detection range) of the camera CR provided on the upper wall portion 20 of the vacuum chamber 2 and close to the first mark M1 provided on the back surface 101B of the substrate 101. Thus, in the alignment of the substrate 101 and the mask 102, the second mark M2 provided on the upper surface 102E of the protrusion 102D of the mask 102 can be detected by the camera CR.

[0056] When the substrate 101 and the mask 102 are aligned, the first mark M1 provided on the substrate 101 and the second mark M2 provided on the mask 102 are detected by the camera CR. In the present embodiment, as described above, the first mark M1 is provided on the back surface 101B of the substrate 101, and the second mark M2 is provided on the upper surface 102E of the protruding portion 102D of the mask 102. Therefore, even when the transmittance of the substrate 101 and the mask 102 with respect to the visible light (measurement light) used in the camera CR is low, the light (reflected light) from the first mark M1 and the second mark M2, respectively, can be detected in the camera CR with a sufficient amount of light. This is because the light from the first mark M1 and the second mark M2 can be detected by the camera CR without transmitting the substrate 101 and the mask 102. By detecting the first mark M1 provided on the back surface 101B of the substrate 101 and the second mark M2 provided on the upper surface 102E of the protruding portion 102D of the mask 102 in this manner, the relative position (positional deviation) of the substrate 101 and the mask 102 can be measured with high accuracy.

[0057] It should be noted that from the perspective of detecting the first mark M1 and the second mark M2 with high accuracy and / or simplifying the structure of the camera CR, it is necessary to bring the first mark M1 and the second mark M2 within the range of the depth of field (depth of focus) of the camera CR. Therefore, the first mark M1 and the second mark M2 are respectively provided on the back surface 101B of the substrate 101 and the upper surface 102E of the protrusion 102D of the mask 102 in such a manner that they are within the range of the depth of field of the camera CR when the substrate 101 and the mask 102 overlap. In other words, the protrusion amount (height in the Z direction) of the protrusion 102D of the mask 102 is set in such a manner that the second mark M2 is within the range of the depth of field of the camera CR with respect to the first mark M1. Specifically, as Figure 3 As shown, the protrusion amount of the protrusion 102D is set so that the position in the height direction (Z direction) of the back side 101B of the substrate 101 held by the substrate holding portion 3 coincides with the position in the height direction of the upper surface 102E of the protrusion 102D. However, the depth of field of the camera CR generally has a certain degree of margin (tolerance), so it is not necessary to strictly coincide the position in the height direction of the back side 101B of the substrate 101 and the position in the height direction of the upper surface 102E of the protrusion 102D. For example, the protrusion amount (P) of the protrusion 102D is set to 1±5% of the sum of the thickness (T) of the substrate 101 and the gap (G) between the substrate 101 and the mask 102 (P=(T+G)×(1±0.05)).

[0058] In addition, in the structure in which the camera CR provided on the upper wall portion 20 of the vacuum chamber 2 detects the light (reflected light) respectively from the first mark M1 and the second mark M2, the substrate holding portion 3 and the mask holding portion 6a also become one of the main reasons for the reduction in the amount of light detected by the camera CR. In particular, when the transmittance of the substrate holding portion 3 and the mask holding portion 6a with respect to the visible light (measurement light) used in the camera CR is low, the reduction in the amount of light detected by the camera CR becomes significant. Therefore, the substrate holding portion 3 is preferably configured so that the first mark M1 provided on the back side 101B of the substrate 101 is exposed while the substrate 101 is maintained. Similarly, the mask holding portion 6a is preferably configured so that the second mark M2 provided on the upper surface 102E of the protrusion 102D of the mask 102 is exposed while the mask 102 is maintained. For example, as Figure 4 As shown, the substrate holding portion 3 is provided with a structure 32 for exposing the first mark M1 at a portion corresponding to the first mark M1 while holding the substrate 101. In addition, the mask holding portion 6a is provided with a structure 62 for exposing the second mark M2 at a portion corresponding to the second mark M2 while holding the mask 102. Specifically, the structure 32 for exposing the first mark M1 and the structure 62 for exposing the second mark M2 include a through hole or a cutout. By configuring the substrate holding portion 3 and the mask holding portion 6a to expose the first mark M1 and the second mark M2, respectively, it is possible to suppress a decrease in the amount of light from the first mark M1 and the second mark M2 detected by the camera CR.

[0059] By detecting the first mark M1 provided on the substrate 101 and the second mark M2 provided on the mask 102 by the camera CR, the relative position (position offset) of the substrate 101 and the mask 102 is measured based on their positions. If the position offset between the substrate 101 and the mask 102 measured by the camera CR (the result of detecting the first mark M1 and the second mark M2) is within the allowable range, the alignment of the substrate 101 and the mask 102 is terminated. On the other hand, if the position offset between the substrate 101 and the mask 102 measured by the camera CR is not within the allowable range, the alignment of the substrate 101 and the mask 102 is performed to reduce the position offset and bring it within the allowable range. Specifically, first, based on the position offset between the substrate 101 and the mask 102 measured by the camera CR, the control amount required to bring the position offset within the allowable range, that is, the displacement amount of the substrate 101 is calculated. The position offset between the substrate 101 and the mask 102 is defined by the distance and direction (X, Y, θ) of the position offset. Then, based on the displacement of the substrate 101 obtained as the control amount, the substrate holding portion 3 is displaced in the XY plane by the position adjustment unit 84 to adjust the relative position of the substrate 101 with respect to the mask 102. The camera CR measures the relative position of the substrate 101 and the mask 102 and the position adjustment unit 84 adjusts the position of the substrate 101 (aligns the substrate 101 and the mask 102) until the positional deviation between the substrate 101 and the mask 102 falls within the allowable range. It should be noted that the determination of whether the positional deviation between the substrate 101 and the mask 102 falls within the allowable range can be performed, for example, by obtaining the distance between the first mark M1 and the second mark M2 and comparing the distance (average value, sum of squares) with a threshold value.

[0060] Next, a film forming process is performed to form a film on the film forming surface 101A of the substrate 101. After the substrate 101 and the mask 102 are aligned, the substrate 101 and the mask 102 are overlapped. For example, by lowering the substrate holding part 3 (driving in the -Z direction), the film forming surface 101A of the substrate 101 is brought into contact with (the facing surface 102A of) the mask 102 as a whole, and the magnet plate 5, the substrate holding part 3, the substrate 101, and the mask 102 are brought into close contact from the top in sequence. As described above, the mask 102 is attracted by the magnet plate 5 by the magnetic force acting between the magnet plate 5 and the mask 102, so that the substrate 101 and the mask 102 can be brought into close contact as a whole. Then, the vapor deposition material is released from the vapor deposition unit 10 by opening the shutter 10a, so that the vapor deposition material is attached to the film forming surface 101A of the substrate 101 through the mask 102, and a film of the vapor deposition material of a predetermined pattern is formed.

[0061] Next, the mask 102 is carried out from (the inner space of) the vacuum chamber 2. First, the substrate 101 and the mask 102 are separated by raising the substrate holding part 3 (driving in the +Z direction). In addition, the conveying unit 131 is positioned below the mask 102, and the mask holding part 6a is lowered (driven in the -Z direction), thereby transferring the mask 102 from the mask holding part 6a to the conveying unit 131. Then, the mask 102 is conveyed to the storage chamber 140 by the conveying unit 131.

[0062] Next, the substrate 101 subjected to the film forming process is carried out from (the inner space of) the vacuum chamber 2. The conveying unit 121 is positioned below the substrate 101, and the substrate holding portion 3 is lowered (driven in the -Z direction), thereby transferring the substrate 101 from the substrate holding portion 3 to the conveying unit 121. Then, the conveying unit 121 conveys the substrate 101 to the conveying path 111.

[0063] In this way, the process of loading the substrate 101, undergoing the film forming process, and unloading the substrate 101 is completed. In this embodiment, as described above, the relative position (positional deviation) of the substrate 101 and the mask 102 can be measured with high accuracy, so the alignment accuracy of the substrate 101 and the mask 102 can be improved. Thus, in the film forming process, a film of a vapor deposition substance of a predetermined pattern can be formed at a predetermined position on the film forming surface 101A of the substrate 101.

[0064] In addition, as the configuration (detection method) of the camera CR for detecting the first mark M1 provided on the back surface 101B of the substrate 101 and the second mark M2 provided on the upper surface 102E of the protruding portion 102D of the mask 102, a transmitted illumination method or a coaxial epi-illumination method is adopted.

[0065] Figure 5 (A) is a diagram schematically showing the structure of a camera CR using a transmission illumination method. In the transmission illumination method, Figure 5 As shown in (A), a light source LS emitting visible light is arranged below the mark M (alignment mark) to be measured, and a sensor SS such as a camera element is arranged above the mark M. Then, the mark M is illuminated from below by the visible light from the light source LS, and the visible light transmitted through the mark M is detected by the sensor SS, thereby detecting (the position of) the mark M. In this way, in the transmission illumination method, it is necessary to arrange the light source LS below the mark M to be measured, so when the transmission illumination method is applied to the film forming apparatus 1, the light source LS is arranged between the substrate 101 and the evaporation unit 10.

[0066] Figure 5 (B) is a diagram schematically showing the structure of a camera CR using a coaxial incident illumination method. In the coaxial incident illumination method, Figure 5As shown in (B), a light source LS and a sensor SS are arranged above a mark M (alignment mark) to be measured, and a semi-transparent mirror HM is arranged between the light source LS and the sensor SS, more specifically, between the light source LS and the mark M. Then, the semi-transparent mirror HM is used to reflect the visible light from the light source LS and illuminate the mark M from above, so that the visible light reflected by the mark M is transmitted through the semi-transparent mirror HM and detected by the sensor SS, thereby detecting (the position of) the mark M. In this way, in the coaxial epi-illumination method, the light source LS can be arranged above the mark M to be measured, so that it can be easily applied to the film forming device 1 compared with the transmission illumination method. In addition, the camera CR adopting the coaxial epi-illumination method has a simple structure and can be realized inexpensively.

[0067] Next, a method for manufacturing an electronic device using the film forming apparatus 1 (the production line 100 including the film forming apparatus 1) in this embodiment will be described. Here, an organic EL display device will be described as an example of an electronic device.

[0068] First, the organic EL display device will be described. Figure 6 (A) is a diagram showing the overall structure of the organic EL display device 50 . Figure 6 (B) is a diagram showing a cross-sectional structure of one pixel of the organic EL display device 50 .

[0069] like Figure 6 As shown in (A), the organic EL display device 50 has a display area 51 in which pixels 52 including a plurality of light-emitting elements are arranged in a matrix. As described later, the plurality of light-emitting elements each have a structure having an organic layer (organic film) sandwiched by a pair of electrodes. It should be noted that, in the present embodiment, a pixel refers to the smallest unit capable of displaying a predetermined color in the display area 51. For example, in the organic EL display device 50, a pixel 52 is formed by a combination of a first light-emitting element 52R, a second light-emitting element 52G, and a third light-emitting element 52B capable of displaying mutually different colors. The pixel 52 is generally composed of a combination of a red light-emitting element, a green light-emitting element, and a blue light-emitting element, but is not limited thereto. For example, it may also be composed of a combination of a yellow light-emitting element, a cyan light-emitting element, and a white light-emitting element, as long as it is composed of light-emitting elements of at least one color.

[0070] Figure 6 (B) is Figure 6A partial cross-sectional view at line AB shown in (A). The pixel 52 is composed of an organic EL element, which has an anode 54, a hole transport layer 55, any one of the light-emitting layers 56R, 56G and 56B, an electron transport layer 57 and a cathode 58 on a substrate 53. Among them, the hole transport layer 55, the light-emitting layers 56R, 56G and 56B, and the electron transport layer 57 are equivalent to organic layers. In addition, in the present embodiment, the light-emitting layer 56R is an organic EL layer that emits red, the light-emitting layer 56G is an organic EL layer that emits green, and the light-emitting layer 56B is an organic EL layer that emits blue. The light-emitting layers 56R, 56G and 56B are respectively formed into patterns corresponding to light-emitting elements (sometimes also recorded as organic EL elements) that emit red, green and blue. In addition, the anode 54 is formed separately for each light-emitting element. The hole transport layer 55, the electron transport layer 57 and the cathode 58 can be formed in common in multiple light-emitting layers 56R, 56G and 56B, or can be formed for each light-emitting element. In order to prevent the anode 54 and the cathode 58 from short-circuiting due to foreign matter, an insulating layer 59 is provided between the electrodes. In addition, since the organic EL layer is degraded by moisture and oxygen, a protective layer PL is provided to protect the organic EL element from moisture and oxygen.

[0071] exist Figure 6 In (B), the hole transport layer 55 and the electron transport layer 57 are shown as one layer, but according to the structure of the organic EL element, they can also be formed by multiple layers including a hole blocking layer and an electron blocking layer. In addition, a hole injection layer having an energy band structure for smoothly injecting holes from the anode 54 to the hole transport layer 55 can also be formed between the anode 54 and the hole transport layer 55. Similarly, an electron injection layer can also be formed between the cathode 58 and the electron transport layer 57.

[0072] Hereinafter, a method for manufacturing an organic EL display device will be described.

[0073] First, a substrate 53 on which a circuit (not shown) for driving the organic EL display device and the anode 54 are formed is prepared.

[0074] Next, an acrylic resin is formed by spin coating on the substrate 53 having the anode 54 formed thereon, and patterned by photolithography to form an opening in the acrylic resin portion having the anode 54 formed thereon, thereby forming an insulating layer 59. This opening corresponds to a light emitting region where the light emitting element actually emits light.

[0075] The substrate 53 on which the insulating layer 59 is patterned is carried into the film forming device 1 (first film forming chamber) of the production line 100, and a hole transport layer 55 is formed as a common layer on the anode 54 of the display area 51. The hole transport layer 55 is formed by vacuum evaporation, for example. The hole transport layer 55 is actually formed in a larger size than the display area 51, so a high-definition mask is not required.

[0076] Next, the substrate 53 formed with the hole transport layer 55 is carried into the film forming apparatus 1 (second film forming chamber). The substrate 53 and the mask are aligned, and a red light emitting layer 56R is formed on the portion of the substrate 53 where the red light emitting element is to be formed through the mask.

[0077] Similar to the film formation of the light-emitting layer 56R, the light-emitting layer 56G emitting green is formed in the film forming device 1 (third film forming chamber), and the light-emitting layer 56B emitting blue is formed in the film forming device 1 (fourth film forming chamber). After the light-emitting layers 56R, 56G, and 56B are formed, the electron transport layer 57 is formed in the film forming device 1 (fifth film forming chamber) over the entire display region 51. The electron transport layer 57 is formed as a layer common to the three light-emitting layers 56R, 56G, and 56B.

[0078] Next, the substrate 53 on which the electron transport layer 57 has been formed is carried into the film forming apparatus 1 (sixth film forming chamber), and the cathode 58 is formed.

[0079] Then, the substrate 53 formed up to the cathode 58 is carried into a sealing device, and a protective layer PL is formed by plasma CVD (sealing process), thereby completing the organic EL display device 50. Here, the protective layer PL is formed by CVD method, but it is not limited to this. For example, the protective layer PL may also be formed by ALD method or inkjet method.

[0080] It should be noted that if the substrate 53 is exposed to an atmosphere containing moisture or oxygen during the period from when the substrate 53 on which the insulating layer 59 is patterned is carried into the film forming apparatus 1 to when the protective layer PL is formed, the light-emitting layer composed of the organic EL material may be degraded. Therefore, it is preferable to carry the substrate 53 in and out of the film forming apparatus in a vacuum atmosphere or an inert gas atmosphere.

[0081] The present invention is not limited to the above-described embodiments, and various modifications and changes can be made within the scope of the gist of the invention.

Claims

1. An alignment device, the alignment device is used for aligning a substrate and a mask, the mask is used to form a pattern on a film-forming surface of the substrate, characterized in that: The alignment device includes a camera, which is arranged on the side opposite to the mask when the substrate and the mask overlap, and detects a first mark and a second mark, wherein the first mark is arranged on the back side of the substrate opposite to the film forming surface, and the second mark is arranged on the mask. The mask includes: a pattern portion including an opening for forming the pattern; and a protrusion portion protruding from an outer edge of a surface of the pattern portion facing the film forming surface toward a side on which the substrate overlaps, The camera detects the second mark provided on the upper surface of the protrusion.

2. The alignment device according to claim 1, characterized in that The protrusion is provided on the outer edge portion so as to protrude along a side surface of the substrate in a state where the substrate and the mask overlap.

3. The alignment device according to claim 1, characterized in that: The first mark is provided on the back surface so as to be within the range of the field of view of the camera in a state where the substrate and the mask overlap.

4. The alignment device according to claim 3, characterized in that: The first mark and the second mark are provided on the back surface and the outer edge portion, respectively, so as to be within the range of the depth of field of the camera when the substrate and the mask overlap.

5. The alignment device according to claim 4, characterized in that: The protrusion amount of the protrusion is set so that the second mark is within the range of the depth of field in a state where the substrate and the mask are overlapped and the first mark is within the range of the depth of field.

6. The alignment device according to claim 4, characterized in that The protrusion amount of the protrusion is set to 1±5% of the sum of the thickness of the substrate and the gap between the substrate and the mask in a state where the substrate and the mask overlap.

7. The alignment device according to claim 4, characterized in that The protrusion amount of the protrusion is set so that the position in the height direction of the rear surface of the substrate coincides with the position in the height direction of the upper surface of the protrusion in a state where the substrate and the mask overlap.

8. The alignment device according to claim 1, characterized in that The alignment device further comprises a first electrostatic chuck, the first electrostatic chuck adsorbs the back surface to hold the substrate, The first electrostatic chuck includes a structure for exposing the first mark at a portion corresponding to the first mark while holding the substrate.

9. The alignment device according to claim 8, characterized in that The formations include through holes or cutouts.

10. The alignment device according to claim 1, characterized in that The alignment device further comprises a second electrostatic chuck, the second electrostatic chuck adsorbs the upper surface to hold the mask, The second electrostatic chuck includes a structure for exposing the second mark at a portion corresponding to the second mark while holding the mask.

11. The alignment device according to claim 10, characterized in that The formations include through holes or cutouts.

12. The alignment device according to claim 1, characterized in that The alignment device also has: a first electrostatic chuck that absorbs the back surface to hold the substrate; and a second electrostatic chuck, wherein the second electrostatic chuck adsorbs the upper surface to hold the mask; The first electrostatic chuck holds the substrate in a manner such that the first mark is exposed. The second electrostatic chuck holds the mask in a manner such that the second mark is exposed.

13. The alignment device according to claim 1, characterized in that The camera detects the first mark and the second mark using visible light.

14. An alignment method for aligning a substrate and a mask, wherein the mask is used to form a pattern on a film-forming surface of the substrate, characterized in that: The alignment method has: A step of detecting a first mark provided on the substrate and a second mark provided on the mask using the alignment device according to claim 1; as well as A step of aligning the substrate and the mask based on a result of detecting the first mark and the second mark.

15. A film forming device, which forms a film on a substrate via a mask, characterized in that: The film forming apparatus includes the alignment device according to claim 1 for aligning the substrate and the mask.

16. A manufacturing method, characterized in that: The manufacturing method manufactures an electronic device using the film forming apparatus according to claim 15 .

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