Film forming apparatus, film forming method, method for manufacturing electronic device, and mask

Abstract

This film forming apparatus is provided with: a vapor deposition means for discharging a vapor deposition substance to a substrate through a mask that has a plurality of openings for forming a film of the vapor deposition substance; and a position adjustment means for adjusting the relative position between the mask and the substrate. The plurality of openings have a tapered shape in which the opening area on the vapor deposition means side is larger than the opening area on the substrate side. After a first discharge of the vapor deposition substance to the substrate by the vapor deposition means, the relative position between the mask and the substrate is adjusted by the position adjustment means so as to change a vapor deposition part of the substrate, and a second discharge of the vapor deposition substance to the substrate by the vapor deposition means is performed.

Description

Film forming apparatus, film forming method, electronic device manufacturing method, and mask

[0001] The present invention relates to a technique for forming a film on a substrate, and relates to a film forming apparatus, a film forming method, a method for manufacturing an electronic device, and a mask.

[0002] In the manufacture of organic electroluminescence (EL) displays and the like, a film of a vapor deposition material is formed on a substrate using a mask. As a pre-processing step for film formation, the mask and the substrate are aligned and then superimposed (see, for example, Patent Document 1). The mask has the same pattern as the pattern to be formed on the substrate, and the desired pattern is formed on the substrate in a single film formation process.

[0003] Japanese Patent Application Laid-Open No. 2022-007538

[0004] In small displays known as microdisplays, the pixel pitch is narrow. One method of dealing with this is to thin the pattern formation area, but this reduces the mask's strength. If the pattern formation area is made thicker, the pixel pitch cannot be made narrow enough, and the amount of deposition material passing through the openings is reduced, which can result in the film (pixel) becoming smaller than the opening.

[0005] The present invention provides a technique that can form finer films while improving the durability of the mask.

[0006] According to the present invention, there is provided a film formation apparatus comprising: a vapor deposition means for ejecting a vapor deposition material onto a substrate through a mask having a plurality of openings for forming a film of the vapor deposition material; and a position adjustment means for adjusting the relative position between the mask and the substrate, wherein the plurality of openings have a tapered shape with a larger opening area on the vapor deposition means side than on the substrate side, and after a first ejection of the vapor deposition material onto the substrate by the vapor deposition means, the position adjustment means adjusts the relative position between the mask and the substrate to change the deposition site on the substrate, and a second ejection of the vapor deposition material onto the substrate by the vapor deposition means is performed.

[0007] According to the present invention, it is possible to provide a technique that can form a finer film while improving the durability of the mask.

[0008] Schematic diagram of a part of a manufacturing line for electronic devices. Schematic diagram of a film formation apparatus according to one embodiment of the present invention. Perspective view of a substrate and a mask, and partial enlarged view of the substrate and the mask. Cross-sectional view taken along line A-A in FIG. 3. Cross-sectional view taken along line B-B in FIG. 3. Cross-sectional view of an opening in a comparative example. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Diagram illustrating the operation of the film formation apparatus of FIG. 2. Overall view of an organic EL display device. Diagram showing the cross-sectional structure of one pixel.

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] First Embodiment Electronic Device Manufacturing Line Figure 1 is a schematic diagram showing a portion of the configuration of an electronic device manufacturing line 100 to which the film forming apparatus of the present invention can be applied. In each drawing, arrows X and Y indicate horizontal directions that are orthogonal to each other, and arrow Z indicates the up-down direction (the direction of gravity). The manufacturing line of Figure 1 is used, for example, for manufacturing light-emitting elements of organic EL display devices. The manufacturing line 100 includes a transfer chamber 120 that is octagonal in plan view. A substrate 101 is carried into the transfer chamber 120 from a transfer path 110, and the substrate 101 on which a film has been formed is carried out from the transfer chamber 120 to a transfer path 111.

[0011] A plurality of film formation apparatuses 1 for performing film formation processing on substrates 101 are arranged around the transfer chamber 120. A transfer chamber 130 is arranged adjacent to each film formation apparatus 1. A storage chamber 140 for storing a mask 102 is arranged around the transfer chamber 130, which has an octagonal shape in a plan view.

[0012] A transport unit 121 that transports the substrate 101 is disposed in the transport chamber 120. The transport unit 121 in this embodiment is a horizontal articulated robot that transports the substrate 101 by mounting it in a horizontal position on its hand portion. The transport unit 121 performs a transport operation of transporting the substrate 101 that is transported from the transport path 110 to the film forming apparatus 1, and a transport operation of transporting the substrate 101 that has been film-formed in the film forming apparatus 1 from the film forming chamber 1 to the transport path 111.

[0013] A transfer unit 131 for transferring the mask 102 is disposed in each transfer chamber 130. The transfer unit 131 in this embodiment is a horizontal articulated robot, and transfers the mask 102 by mounting it in a horizontal position on its hand portion. The transfer unit 131 performs an operation of transferring the mask 102 from the storage chamber 140 to the film forming apparatus 1, and an operation of transferring the mask 102 from the film forming apparatus 1 to the storage chamber 140.

[0014] <Film Forming Apparatus> Fig. 2 is a schematic diagram of a film forming apparatus 1 according to one embodiment of the present invention. The film forming apparatus 1 is an apparatus for forming a film of a vapor deposition material on a substrate 101, and forms a thin film of the vapor deposition material in a predetermined pattern using a mask 102. The material of the substrate 101 on which a film is formed in the film forming apparatus 1 can be appropriately selected from materials such as glass, resin, and metal. In particular, in this embodiment, the substrate 101 is, for example, a glass substrate on which TFTs (Thin Film Transistors) are formed or a semiconductor wafer (silicon wafer) on which semiconductor elements are formed.

[0015] The deposition material may be an organic material, an inorganic material (metal, metal oxide, etc.), or the like. The film formation apparatus 1 is applicable to manufacturing apparatuses for manufacturing electronic devices such as display devices (flat panel displays, etc.), thin-film solar cells, and organic photoelectric conversion elements (organic thin-film imaging elements), as well as optical components, and is particularly applicable to manufacturing apparatuses for manufacturing organic EL panels. In the following description, an example will be described in which the film formation apparatus 1 forms a film on the substrate 101 by vacuum deposition, but the present invention is not limited to this, and various film formation methods such as sputtering and CVD can be applied.

[0016] The film forming apparatus 1 has a box-shaped vacuum chamber 2. The internal space of the vacuum chamber 2 is maintained in a vacuum atmosphere or an inert gas atmosphere such as nitrogen gas. In this embodiment, the vacuum chamber 2 is connected to a vacuum pump (not shown). A vapor deposition unit 10 is disposed in the internal space of the vacuum chamber 2. The vapor deposition unit 10 includes a vapor deposition source that releases a vapor deposition material upward. A shutter 10a that restricts and releases the release of the vapor deposition material is disposed above the vapor deposition unit 10. The shutter 10a is opened and closed by an opening / closing mechanism (not shown). FIG. 2 shows the shutter 10a in a closed state, restricting the release of the vapor deposition material from the vapor deposition unit 10. An adhesion prevention plate 2a is also disposed above the vapor deposition unit 10. The adhesion prevention plate 2a prevents the vapor deposition material from undesirably adhering to the following components disposed above the internal space of the vacuum chamber 2.

[0017] A substrate support plate 3 that supports the substrate 101 in a horizontal position is provided in the internal space of the vacuum chamber 2. In this embodiment, the substrate support plate 3 is an electrostatic chuck that attracts and holds the substrate 101 to its lower surface by electrostatic force. A cooling plate 4 is fixed on the substrate support plate 3. The cooling plate 4 is equipped with, for example, a water cooling mechanism, and cools the substrate 101 via the substrate support plate 3 during film formation.

[0018] The substrate support plate 3 and the cooling plate 4 are suspended from a magnetic plate 5 via support portions 5a so as to be displaceable in the Z direction. The magnetic plate 5 is a plate that attracts the mask 102 by magnetic force. During film formation, the substrate 101 is sandwiched between the magnetic plate 5 and the mask 102 by magnetic force, which improves the adhesion between the substrate 101 and the mask 102.

[0019] The film forming apparatus 1 includes a mask support unit 6 that supports the mask 102 during film formation. In this embodiment, the mask support unit 6 also transfers the substrate 101 between the transport unit 121 and the substrate support plate 3. The mask support unit 6 includes a pair of support members 6a spaced apart in the X direction. Each support member 6a is raised and lowered by a corresponding actuator 6b. In this embodiment, an actuator 6b is provided for each support member 6a. However, a single actuator 6b may be used to raise and lower the pair of support members 6a. The actuator 6b may be, for example, an electric cylinder or an electric ball screw mechanism. The support member 6a includes a claw F1 at its lower end. The peripheral edge of the substrate 101 or mask 102 is placed on the claw F1. In the example of FIG. 2, the mask 102 is placed on the claw F1. The pair of support members 6a are raised and lowered synchronously to raise and lower the substrate 101 or mask 102. The claw F1 may have a mechanism for releasably holding the mask 102.

[0020] The film forming apparatus 1 includes an alignment unit 8 that aligns the substrate 101 and the mask 102. The alignment apparatus 8 includes a drive mechanism 80 and a plurality of measurement units SR. The drive mechanism 80 includes a distance adjustment unit 81, a support shaft 82, a stand 83, and a position adjustment unit 84.

[0021] The distance adjustment unit 81 is a mechanism for raising and lowering the support shaft 82 in the Z direction, and includes, for example, an electric cylinder or an electric ball screw mechanism. A magnet plate 5 is fixed to the lower end of the support shaft 82, and raising and lowering the support shaft 82 raises and lowers the substrate support plate 3 via the magnet plate 5. By raising and lowering the substrate support plate 3, the distance between the substrate 101 and the mask 102 is adjusted, and the substrate 101 and the mask 102 supported by the substrate support plate 3 are moved closer to or farther apart in the thickness direction (Z direction) of the substrate 101. In other words, the distance adjustment unit 81 brings the substrate 101 and the mask 102 closer to or farther apart in the overlapping direction. Note that the "distance" adjusted by the distance adjustment unit 81 is the so-called vertical distance (or perpendicular distance), and the distance adjustment unit 81 can also be said to be a unit that adjusts the vertical position of the substrate 101. The distance adjustment unit 81 is mounted on the position adjustment unit 84 via a stand 83.

[0022] The position adjustment unit 84 adjusts the relative position of the substrate 101 with respect to the mask 102 by displacing the substrate support plate 3 on the X-Y plane. In other words, the position adjustment unit 80 can also be said to be a unit that adjusts the horizontal positions of the mask 102 and the substrate 101. The position adjustment unit 80 can displace the substrate support plate 6 in a rotational direction (θ direction) around axes in the X, Y, and Z directions. In this embodiment, the position of the mask 102 is fixed and the substrate 101 is displaced to adjust their relative positions, but the mask 102 may also be displaced to adjust the position, or both the substrate 101 and the mask 102 may be displaced.

[0023] The position adjustment unit 84 includes a fixed plate 20a and a movable plate 20b. The fixed plate 84a and the movable plate 84b are rectangular frame-shaped plates, and the fixed plate 84a is fixed onto the upper wall 20 of the vacuum chamber 2. An actuator is provided between the fixed plate 20a and the movable plate 20b to displace the movable plate 20b relative to the fixed plate 20a in the X-direction, Y-direction, and rotational directions around the Z-direction axes.

[0024] A frame-shaped base 83 is mounted on the movable plate 84b, and the base 83 supports the distance adjustment unit 81. When the movable plate 84b is displaced, the base 83 and the distance adjustment unit 81 are displaced together. This allows the substrate 101 to be displaced in the X-, Y-, and Z-direction rotational directions around the axes. Openings are formed in the upper wall 20, through which the support shaft 82 and the support members 6a and 7a pass. These openings are sealed with sealing members (such as bellows) (not shown), maintaining airtightness within the vacuum chamber 2.

[0025] The measurement unit SR measures the positional misalignment between the substrate 101 and the mask 102. In this embodiment, the measurement unit SR is an imaging device (camera) that captures images. The measurement unit SR is disposed on the upper wall portion 20 and is capable of capturing images inside the vacuum chamber 2. Alignment marks (not shown) are formed on the substrate 101 and the mask 102, respectively. The measurement unit SR captures images of each alignment mark on the substrate 101 and the mask 102. The amount of positional misalignment between the substrate 101 and the mask 102 is calculated based on the position of each alignment mark, and the position adjustment unit 84 adjusts the relative positions of the substrate 101 and the mask 102 to eliminate the amount of positional misalignment.

[0026] The control device 9 controls the entire film forming apparatus 1. The control device 9 includes a processing unit 90, a storage unit 91, an input / output interface (I / O) 92, and a communication unit 93. The processing unit 90 is a processor typified by a CPU, and controls the film forming apparatus 1 by executing a program stored in the storage unit 92. The storage unit 91 is a storage device such as a ROM, RAM, or HDD, and stores various control information in addition to the program executed by the processing unit 90. The I / O 92 is an interface that transmits and receives signals between the processing unit 90 and an external device. The communication unit 93 is a communication device that communicates with a higher-level device or another control device via a communication line.

[0027] 3 shows an example of a substrate 101, a mask 102, and an electrostatic chuck 103. The substrate 101 is a circular silicon wafer, and after film formation and the like, a plurality of chips 101a are cut out from the substrate 101. In the illustrated example, it is assumed that a matrix pattern of a plurality of pixels 101b of a predetermined color (e.g., red, blue, or green) is formed for each chip 101a by the film formation device 1. Adjacent pixels 101b in the X direction are spaced apart by a pitch P0.

[0028] The mask 102, like the substrate 101, is a circular member and includes a mask portion 102b corresponding to each chip 101a and a frame portion 102a surrounding the mask portion 102b. The mask portion 102b has multiple openings (through holes) 102c formed therein through which the deposition material to be deposited on the substrate 101 passes. The arrangement of the openings 102c defines the film formation pattern on the substrate 101. The multiple openings 101b form a matrix pattern, and the number and position (pitch) of the openings 101b in the Y direction coincide with the pixels 101b. Meanwhile, the pitch P1 of the openings 101b in the X direction is longer than the pitch P0. In this embodiment, the pitch P1 is an integer multiple of the pitch P0, as shown by P1 = N × P0 (N is an integer greater than or equal to 2), where N = 2 in the illustrated example. Therefore, the number of openings 101b in the X direction is half the number of pixels 101b in the X direction.

[0029] 4A and 4B are cross-sectional views taken along lines A-A and B-B in FIG. 3. The mask 102 is made of, for example, a silicon plate (a silicon plate). By using a silicon wafer as the mask 102, finer and more precise openings 102c can be formed by applying semiconductor manufacturing techniques. The frame portion 102a is a relatively thick portion, and the mask portion 102b is a relatively thin portion. The frame portion 102a has higher rigidity than the mask portion 102b. The mask portion 102b can be made thinner without significantly reducing the overall rigidity of the mask 102. By providing a magnetic material (not shown) in the frame portion 102a, the magnetic force of the magnet plate 5 can be used to tightly attach the mask 102 to the substrate 101 during film formation. The magnetic material is, for example, a thin film of a magnetic material such as nickel (Ni).

[0030] The opening 102c has a tapered shape with a larger opening area on the deposition unit 10 side than on the substrate 101 side. In this embodiment, the opening 102c has a truncated cone shape, with one end on the deposition unit 10 side having a diameter D2 and the other end on the substrate 101 side having a diameter D1 (<D2). The taper angle θ is the angle between the surface of the mask 102 facing the substrate 101 and the inner circumferential surface of the opening 102c, and the thickness t is the thickness of the mask portion 102b. The opening 102c may have a truncated pyramid shape.

[0031] Here, if the thickness t is small, the strength of the mask portion 102b decreases, and if particles get between the substrate 101 and the mask portion 102b during film formation, the mask portion 102b may be damaged. If the thickness t is large, and the opening 102c has a cylindrical or other cylindrical shape, the amount of evaporation material passing through the opening 102c may decrease. FIG. 4C shows an example of a cylindrical opening 102c as a comparative example. With such a shape, if the thickness t is large, the evaporation material that is obliquely incident on the opening 102c cannot pass through the opening 102c, as shown by the dashed line. As a result, a phenomenon occurs in which the film (pixel) to be formed is smaller than the cross-sectional area of ​​the opening 102c.

[0032] The tapered shape of the openings 102c as in this embodiment allows the deposition material to pass through the openings 102c more easily. Therefore, a film (pixel) can be formed that corresponds to the cross-sectional area of ​​the openings 102c on the substrate 101 side while increasing the thickness t. On the other hand, when the openings 102c have a tapered shape as in this embodiment, the cross-sectional area on the deposition unit 10 side increases. If the pitch P1 of the openings 102c is to be matched with the pitch P0 of the pixels 101b, the openings 102c cannot be arranged according to the number of pixels 101b, or the taper angle θ is restricted.

[0033] Therefore, in this embodiment, film formation on the substrate 101 is performed in multiple stages using the mask 102. In this embodiment, since the relationship P1 = 2 × P0 holds, film formation on the substrate 101 is performed in two stages. Specifically, in the first film formation, multiple pixels 101b are formed on the substrate 101 at a pitch P1. Thereafter, the relative position of the substrate 101 and the mask 102 in the X direction is adjusted to change the deposition location on the substrate. The adjustment of the relative position is a displacement shorter than the pitch P1 of the openings 102c. In this embodiment, the relative position is adjusted by the pitch P0. Then, a second film formation is performed. As a result, multiple pixels 101b are formed on the substrate 101 at the desired pitch P0.

[0034] In this manner, in this embodiment, by combining the shape of the opening 102c and multi-stage film formation, it is possible to form a finer film while increasing the thickness t and improving the durability of the mask 102. Note that if the relationship P1 = 3 × P0 holds, film formation on the substrate 101 can be performed in three stages, and if the relationship P1 = 4 × P0 holds, film formation on the substrate 101 can be performed in four stages.

[0035] As an example, the number of times film formation is performed in multiple stages can be determined from the diameter D2 of the opening 102c and the pixel pitch P0 of the pixels 101b as follows: Number of times film formation ≧ D2 ÷ P0 The diameter D2 is calculated from the thickness t, taper angle θ, and diameter D1 of the opening 102c as follows: D2 = t ÷ (tan θ × 2) + D1 Therefore, the number of times film formation can also be determined from the thickness t, taper angle θ, diameter D1 of the opening 102c, and pixel pitch P0 of the pixels 101b as follows: Number of times film formation ≧ (t ÷ (tan θ × 2) + D1) ÷ P0 Each parameter can be designed appropriately within a range that satisfies the above relational expression.

[0036] <Control Example> A description will be given of a control example of the film forming apparatus 1 executed by the processing unit 90 of the control unit 9. Figures 5 to 11 are explanatory diagrams of the operation of the film forming apparatus 1, showing an example from loading of the substrate 101 to film formation and unloading.

[0037] State ST51 in Figure 5 shows a state in which the substrate 101 has been carried into the vacuum chamber 2. The substrate 101 is carried below the substrate support plate 3 by the transport robot 121. The substrate attraction surface 3a on the underside of the substrate support plate 3 is horizontal. Next, the mask support unit 6 transfers the substrate 101 from the transport robot 121 to the substrate support plate 3. State ST52 in Figure 5 shows this operation. By raising the support member 6a, the peripheral edge of the substrate 101 is placed on the claw portion F1, and the substrate 101 is raised from the transport robot 121 and pressed against the substrate attraction surface 3a of the substrate support plate 3. The electrostatic chuck of the substrate support plate 3 is activated to attract and hold the substrate 101.

[0038] Next, the mask 102 is carried into the vacuum chamber 2. State ST61 in FIG. 6 shows a state in which the mask 102 has been carried into the vacuum chamber 2. The mask 102 is carried into the vacuum chamber 2 from the storage chamber 140 by the transport robot 131. The mask 102 is positioned directly below the substrate 101. Next, the mask 102 is transferred from the transport robot 131 to the mask support unit 6 and positioned at the alignment position. State ST62 in FIG. 6 shows this operation. By raising the support members 6a, the periphery of the mask 102 is placed on the claws F1, and the mask 102 is raised from the transport robot 131. The mask 102 is supported by the support members 6a, and by further raising, it is positioned at the alignment position. In this embodiment, the mask 102 is raised to be positioned at the alignment position, but a configuration in which the substrate 101 is lowered to be positioned at the alignment position may also be used.

[0039] Next, an alignment operation is performed. As shown in state ST71 in Figure 7, the measurement unit SR measures the relative positions of the alignment marks on the substrate 101 and the mask 102. If the measurement result (the amount of misalignment between the substrate 101 and the mask 102) is within the allowable range, the alignment operation is terminated. If the measurement result is outside the allowable range, a control amount (the amount of displacement of the substrate 101) is set based on the measurement result to bring the amount of misalignment within the allowable range.

[0040] The "amount of misalignment" is defined as the distance and direction (X, Y, θ) of the misalignment. Based on the set control amount, the position adjustment unit 80 is operated as shown in state ST71 in Figure 7. As a result, the substrate support plate 3 is displaced on the XY plane, and the relative position of the substrate 101 with respect to the mask 102 is adjusted.

[0041] Whether or not the measurement results are within the allowable range can be determined, for example, by calculating the distances between the alignment marks and comparing the average value or sum of squares of the distances with a preset threshold value.

[0042] After adjusting the relative positions, the measurement unit SR again measures the relative positions of the alignment marks on the substrate 101 and the mask 102. If the measurement result is within the tolerance range, the alignment operation is terminated. If the measurement result is outside the tolerance range, the relative position of the substrate 101 with respect to the mask 102 is adjusted again. Thereafter, measurement and relative position adjustment are repeated until the measurement result falls within the tolerance range.

[0043] Next, the first film formation operation is performed. First, the substrate 101 is placed on the mask 102. State ST81 in FIG. 8 shows this operation. When the substrate support plate 3 is lowered, the substrate 101 is placed on the mask 102, and the entire surface to be processed of the substrate 101 comes into contact with the mask 102. The magnetic plate 5 abuts on the cooling plate 4, and from above, the magnetic plate 5, cooling plate 4, substrate support plate 3, substrate 101, and mask 102 are in close contact. The magnetic force of the magnetic plate 5 attracts the mask 102, allowing the mask 102 and the substrate 101 to be in close contact with each other overall.

[0044] 8, the shutter 10a is opened and the deposition material is released from the deposition unit 10. The deposition material is deposited on the substrate 101 through the mask 102.

[0045] After the first release of the evaporation material, the evaporation site on the substrate 101 is changed by adjusting the relative positions of the mask 102 and the substrate 101. First, as shown in state ST91 in Figure 9 , the magnet plate 5 is raised to separate the substrate 101 and the mask 102 in the Z direction. Next, as shown in state ST92 in Figure 9 , the position adjustment unit 80 moves the substrate 101 in the X direction by a distance P0. This changes the evaporation site on the substrate 101.

[0046] In this embodiment, when changing the deposition site, the substrate 101 is moved in the X direction by a distance P0. However, alignment marks for the substrate 101 and the mask 102 for the second film formation operation may be provided, and alignment may be performed in the same manner as in the example of FIG. 7 to change the relative positions of the substrate 101 and the mask 102.

[0047] Next, a second film formation operation is performed. The procedure is the same as the first film formation operation. First, the substrate 101 is superimposed on the mask 102. State ST101 in FIG. 10 shows this operation. When the substrate support plate 3 is lowered, the substrate 101 is placed on the mask 102, and the entire surface to be processed of the substrate 101 comes into contact with the mask 102. The magnetic plate 5 abuts on the cooling plate 4, and from above, the magnetic plate 5, cooling plate 4, substrate support plate 3, substrate 101, and mask 102 are in close contact. The magnetic force of the magnetic plate 5 attracts the mask 102, allowing the mask 102 and the substrate 101 to be in close contact with each other overall.

[0048] 10, the shutter 10a is opened and the deposition material is released from the deposition unit 10. The deposition material is deposited on the substrate 101 through the mask 102.

[0049] By the above procedure, the pixels 101b having the pitch P0 shown in FIG. 3 can be formed on the substrate 101 using the mask 102 having the openings 102c having the pitch P1 shown in FIG.

[0050] When this film formation is completed, the mask 102 and the substrate 101 are each unloaded. State ST111 in FIG. 11 shows the operation of unloading the mask 102. First, the magnetic plate 5 is raised, and the substrate 101 and the mask 102 are separated from each other. After the hand portion of the transport robot 131 is advanced below the mask 102, the support member 6a of the mask support unit 6 is lowered, and the mask 102 is transferred from the support member 6a to the transport robot 131. The transport robot 131 transports the mask 102 to the storage chamber 140.

[0051] Next, the substrate 101 on which the film has been formed is carried out. The support members 6a of the mask support unit 6 are raised, and the substrate 101 is supported from below by the claws F1. The suction of the substrate support unit 3 to the substrate 101 is released, and the substrate 101 is transferred to the support members 6a. After the hand portion of the transport robot 121 is advanced below the substrate 101, the support members 6a of the mask support unit 6 are lowered, and the substrate 101 is transferred from the support members 6a to the transport robot 121, as shown in state ST112 in FIG. 11 . The transport robot 121 transports the substrate 101 to the transport path 111. This completes the operations from carrying in the substrate 101, to film formation, and carrying it out.

[0052] Second Embodiment In the first embodiment, the pitch in the X direction between the pixels 101b and the openings 102c has a relationship of P1 = N × P0, but the pitch in the Y direction may also be set to be the pitch of the openings 102c = n × the pitch of the pixels 10b (n is an integer equal to or greater than 2). In this case, the change of the deposition site and the film formation operation shown in Figures 9 and 10 may be performed n-1 times in the Y direction.

[0053] Third Embodiment Next, an example of a method for manufacturing an electronic device will be described. The configuration and manufacturing method of an organic EL display device will be exemplified below as an example of the electronic device.

[0054] First, the organic EL display device to be manufactured will be described. Fig. 12A is an overall view of the organic EL display device 50, and Fig. 12B is a diagram showing the cross-sectional structure of one pixel.

[0055] 12A, a plurality of pixels 52, each including a plurality of light-emitting elements, are arranged in a matrix in a display region 51 of an organic EL display device 50. As will be described in detail later, each of the light-emitting elements has a structure including an organic layer sandwiched between a pair of electrodes.

[0056] Note that the term "pixel" as used herein refers to the smallest unit capable of displaying a desired color in the display region 51. In the case of a color organic EL display device, a pixel 52 is configured by a combination of multiple pixels (called sub-pixels to distinguish them from the entire pixel) each consisting of a first light-emitting element 52R, a second light-emitting element 52G, and a third light-emitting element 52B, each of which emits light differently from one another. The pixel 52 is often configured by a combination of three types of sub-pixels: a red (R) light-emitting element, a green (G) light-emitting element, and a blue (B) light-emitting element, but this is not limited thereto. The pixel 52 may include at least one type of sub-pixel, preferably two or more types of sub-pixels, and more preferably three or more types of sub-pixels. The sub-pixels constituting the pixel 52 may be, for example, a combination of four types of sub-pixels: a red (R) light-emitting element, a green (G) light-emitting element, a blue (B) light-emitting element, and a yellow (Y) light-emitting element.

[0057] 12B is a partial cross-sectional schematic diagram taken along line A-B in FIG. 12A. A pixel 52 has, on a substrate 53, a plurality of sub-pixels each composed of an organic EL element including a first electrode (anode) 54, a hole transport layer 55, one of a red layer 56R, a green layer 56G, and a blue layer 56B, an electron transport layer 57, and a second electrode (cathode) 58. Of these, the hole transport layer 55, the red layer 56R, the green layer 56G, the blue layer 56B, and the electron transport layer 57 correspond to organic layers. The red layer 56R, the green layer 56G, and the blue layer 56B are formed in patterns corresponding to light-emitting elements (sometimes referred to as organic EL elements) that emit red, green, and blue light, respectively.

[0058] 12B , the hole transport layer 55 may be formed as a common layer across the plurality of sub-pixel regions, and thereon the red layer 56R, the green layer 56G, and the blue layer 56B may be formed separately for each sub-pixel region, and thereon the electron transport layer 57 and the second electrode 58 may be formed as a common layer across the plurality of sub-pixel regions.

[0059] In order to prevent short circuits between adjacent first electrodes 54, an insulating layer 59 is provided between the first electrodes 54. Furthermore, since the organic EL layer deteriorates due to moisture and oxygen, a protective layer 60 is provided to protect the organic EL element from moisture and oxygen.

[0060] 12B shows the hole transport layer 55 and the electron transport layer 57 as a single layer, they may be formed of multiple layers including a hole blocking layer and an electron blocking layer depending on the structure of the organic EL display element. Furthermore, a hole injection layer having an energy band structure that can smoothly inject holes from the first electrode 54 to the hole transport layer 55 may be formed between the first electrode 54 and the hole transport layer 55. Similarly, an electron injection layer may be formed between the second electrode 58 and the electron transport layer 57.

[0061] Each of the red layer 56R, green layer 56G, and blue layer 56B may be formed of a single light-emitting layer or may be formed by laminating multiple layers. For example, the red layer 56R may be formed of two layers, with the upper layer being a red light-emitting layer and the lower layer being a hole transport layer or an electron blocking layer. Alternatively, the lower layer may be a red light-emitting layer and the upper layer being an electron transport layer or a hole blocking layer. By providing a layer below or above the light-emitting layer in this manner, the light-emitting position in the light-emitting layer can be adjusted, and the optical path length can be adjusted, thereby improving the color purity of the light-emitting element.

[0062] Although the red layer 56R is shown as an example here, a similar structure may be adopted for the green layer 56G or the blue layer 56B. The number of layers may be two or more. Furthermore, layers of different materials may be stacked, such as a light-emitting layer and an electron-blocking layer, or layers of the same material may be stacked, such as two or more light-emitting layers.

[0063] Next, an example of a manufacturing method for an organic EL display device will be specifically described. Here, it is assumed that the red layer 56R is composed of two layers, a lower layer 56R1 and an upper layer 56R2, and the green layer 56G and the blue layer 56B are composed of a single light-emitting layer. It is assumed that the film forming apparatus 1 is arranged in six film forming chambers.

[0064] First, a substrate 53 is prepared on which a circuit (not shown) for driving the organic EL display device and a first electrode 54 are formed. The material of the substrate 53 is not particularly limited, and it can be made of glass, plastic, metal, etc. In this embodiment, a substrate in which a polyimide film is laminated on a glass substrate is used as the substrate 53.

[0065] A resin layer such as acrylic or polyimide is coated by bar coating or spin coating on the substrate 53 on which the first electrode 54 is formed, and the resin layer is patterned by lithography so as to form an opening in the area where the first electrode 54 is formed, thereby forming an insulating layer 59. This opening corresponds to the light-emitting region where the light-emitting element actually emits light. In this embodiment, the large substrate is processed up to the formation of the insulating layer 59, and after the insulating layer 59 is formed, a dividing step is carried out to divide the substrate 53.

[0066] The substrate 53 with the patterned insulating layer 59 is carried into a first film-forming chamber, and a hole transport layer 55 is formed as a common layer on the first electrodes 54 in the display region. The hole transport layer 55 is formed using a mask having openings formed for each display region 51 that will ultimately become the panel portion of each organic EL display device.

[0067] Next, the substrate 53 on which the hole transport layer 55 has been formed is carried into a second film formation chamber. The substrate 53 and a mask are aligned, and the substrate is placed on the mask. A red layer 56R is then formed on the hole transport layer 55 in the portion of the substrate 53 where the red-emitting elements are to be disposed (the region where the red subpixels are to be formed). The mask used in the second film formation chamber is a high-definition mask with openings formed only in the regions that will become the red subpixels among the regions on the substrate 53 that will become the subpixels of the organic EL display device. As a result, the red layer 56R including the red light-emitting layer is formed only in the regions that will become the red subpixels among the regions on the substrate 53 that will become the red subpixels. In other words, the red layer 56R is selectively formed in the regions that will become the red subpixels, but not in the regions that will become the blue or green subpixels among the regions on the substrate 53 that will become the subpixels.

[0068] Similar to the formation of the red layer 56R, the green layer 56G is formed in the third film formation chamber, and then the blue layer 56B is formed in the fourth film formation chamber. After the formation of the red layer 56R, green layer 56G, and blue layer 56B is completed, the electron transport layer 57 is formed over the entire display area 51 in the fifth film formation chamber. The electron transport layer 57 is formed as a layer common to the three color layers 56R, 56G, and 56B.

[0069] The substrate on which the electron transport layer 57 has been formed is moved to a sixth film-forming chamber, where the second electrode 58 is formed. In this embodiment, each layer is formed by vacuum deposition in the first to sixth film-forming chambers. However, the present invention is not limited to this, and for example, the second electrode 58 in the sixth film-forming chamber may be formed by sputtering. Thereafter, the substrate on which the second electrode 58 has been formed is moved to a sealing device, where the protective layer 60 is formed by plasma CVD (sealing step), thereby completing the organic EL display device 50. Note that, although the protective layer 60 is formed by the CVD method here, the method is not limited thereto, and it may also be formed by an ALD method or an inkjet method.

[0070] Here, the films are formed in the first to sixth film formation chambers using a mask having an opening corresponding to the pattern of each layer to be formed. During film formation, the relative positions of the substrate 53 and the mask are adjusted (aligned), and then the substrate 53 is placed on the mask and film formation is performed.

[0071] The present invention can also be realized by a process in which a program that realizes one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., an ASIC) that realizes one or more of the functions.

[0072] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention.

[0073] 1 Film forming apparatus, 5 Magnetic plate, 8 Alignment unit, 10 Vapor deposition unit, 101 Substrate, 102 Mask, 1021 Magnetic material

Claims

1. A film formation apparatus comprising: a vapor deposition means for ejecting a vapor deposition material onto a substrate through a mask having a plurality of openings for forming a film of the vapor deposition material; and a position adjustment means for adjusting the relative position between the mask and the substrate, wherein the plurality of openings have a tapered shape with a larger opening area on the vapor deposition means side than on the substrate side, and wherein after a first ejection of the vapor deposition material onto the substrate by the vapor deposition means, the position adjustment means adjusts the relative position between the mask and the substrate to change the deposition site on the substrate, and a second ejection of the vapor deposition material onto the substrate by the vapor deposition means is performed.

2. A film forming apparatus according to claim 1, characterized in that the first emission, the change of the deposition site, and the second emission are carried out during the period from when the substrate is carried into the film forming apparatus until when it is carried out of the film forming apparatus.

3. A film forming apparatus according to claim 1, characterized in that a plurality of pixels of a predetermined color are formed on the substrate by the first emission and the second emission.

4. A film forming apparatus according to claim 1, characterized in that, after the first emission, the position adjustment means adjusts the relative position by a distance shorter than a distance between adjacent openings.

5. A film forming apparatus as described in claim 1, characterized in that a plurality of pixels at a first pitch are formed on the substrate by the deposition material, the plurality of openings are formed at a second pitch which is an integer multiple of the first pitch that is two or more, and the position adjustment means adjusts the relative position by the first pitch after the first emission.

6. The film forming apparatus according to claim 1, wherein the substrate is a semiconductor wafer, and the mask is a silicon plate.

7. A film forming method comprising: a first deposition step of releasing a deposition material from a deposition means onto a substrate through a mask having a plurality of openings for depositing the deposition material; a change step of changing a deposition site on the substrate by adjusting the relative position of the mask and the substrate; and a second deposition step of releasing the deposition material from the deposition means onto the substrate through the mask, wherein the plurality of openings have a tapered shape with a larger opening area on the deposition means side than on the substrate side.

8. A film forming method comprising: a deposition step of releasing a deposition material from a deposition means onto a substrate through a mask having a plurality of openings for depositing a film of the deposition material; and a modification step of modifying a deposition site on the substrate by adjusting the relative position of the mask and the substrate, wherein the plurality of openings have a truncated cone shape with a larger opening area on the deposition means side than on the substrate side, the deposition step and the modification step are repeated a predetermined number of times, and the relationship among the predetermined number of times, the diameter of the plurality of openings on the deposition means side, and the pitch at which the film is deposited on the substrate is the predetermined number of times≧the diameter÷the pitch.

9. A method for manufacturing an electronic device, comprising the step of forming a film on a substrate by the film forming apparatus according to claim 1.

10. A mask having a plurality of openings for depositing a plurality of pixels of a deposition material on a substrate, wherein the pitch of the plurality of openings is longer than the pitch of the plurality of pixels, and the plurality of openings have a tapered shape with an opening area larger at one end than at the other end.

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