JP2009041054A - Mask for vapor deposition, its manufacturing method, and manufacturing method of display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a mask for vapor deposition, a mask for vapor deposition, and a manufacturing method of a display device in which a multiple pattern can be materialized while forming a through hole pattern with excellent accuracy. <P>SOLUTION: In the manufacturing method of a mask 1 for vapor deposition, a plurality of metallic thin films 10 are fixed to a frame 11 while applying the tension T thereto, and then, a plurality of through hole patterns 10A are formed in each metallic thin film 10. The through hole patterns 10A are formed on a surface side and a back side of each metallic thin film 10 successively via steps of forming photoresist film, of drawing patterns by the laser direct exposure method, of developing a photoresist film, of performing the etching, of peeling the photoresist film, and of water-rinsing and drying. Excellent relative positional accuracy of the through holes 10A-1 between the plurality of metallic thin films 10 is ensured in addition to the excellent dimensional accuracy and the excellent positional accuracy of the through holes 10A-1 in a metallic thin film single body. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an evaporation mask used in a manufacturing process of a display device such as an organic EL (Electro Luminescence) display, a manufacturing method thereof, and a manufacturing method of the display device.

  Conventionally, in a manufacturing process of an organic EL color display made of an organic EL light emitting element, an organic layer made of an organic material is formed by vacuum deposition, and at this time, a plurality of transmissions for transmitting the material in accordance with the pattern of the organic layer are made. A vapor deposition mask provided with holes (transmission hole patterns) is used. In general, the mask for vapor deposition is peeled after the pattern of the through-hole is etched after the pattern exposure of the metal thin film using a photoresist film, for example, or by electroplating the glass master disk with a desired pattern. It can be formed by electroforming. Such an evaporation mask is required to be accurately formed in a desired pattern such as the position and shape of the transmission hole in order to deposit an organic layer in a desired shape at a desired position.

Therefore, for example, there is a method for manufacturing a vapor deposition mask in which an effective transmission hole can be formed with a predetermined size by drawing a pattern on a metal thin film by exposure using a photomask and then performing etching from the vapor deposition source side. It has been proposed (see Patent Document 1). In addition, a technique for improving the dimensional accuracy of the transmission hole pattern by adopting a hybrid two-layer structure using both an etching method and an electroforming method has been proposed (see Patent Document 2). In addition, after forming the transmission hole pattern, by partially pulling the metal thin film and fixing it to the frame while applying tension, tension is applied to the mask body while adjusting to the desired dimensions as a deposition mask, There has been proposed a technique for preventing slack and displacement (see Patent Document 3).
JP 2005-183153 A JP 2005-314787 A JP 2004-225077 A JP 2001-237073 A

  On the other hand, in recent years, a large-sized organic EL color display has been developed, and accordingly, there is an increasing demand for increasing the size of the evaporation mask. However, in the methods of Patent Documents 1 to 3, it is difficult in handling to increase the size of the mask alone in accordance with the display size. Therefore, Patent Document 4 proposes a method of manufacturing a vapor deposition mask that enables multiple chamfering by fixing a plurality of masks each having a transmission hole pattern to a frame and assembling them. .

  However, in order to accurately form a multi-faceted vapor deposition mask to accommodate a large display, in addition to the accuracy of the shape and position of the transmission hole pattern in each mask, it can be used between each mask in the assembled state. It is required that the relative positional accuracy of the transmission hole pattern is good. The configuration of the above-mentioned Patent Document 4 has a problem that the accuracy is insufficient.

  SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and an object of the present invention is to provide a method for manufacturing a vapor deposition mask, a vapor deposition mask, and a display device capable of realizing multiple chamfering while accurately forming a transmission hole pattern. It is in providing the manufacturing method of.

  The method for manufacturing a vapor deposition mask according to the present invention includes a stretching step of fixing a plurality of metal thin films for a mask to a frame having an opening while applying tension so as to cover the opening, and fixing to the frame. And a through hole forming step of forming a plurality of through holes for allowing the vapor deposition material to pass through the plurality of metal thin films.

  In the method for manufacturing a deposition mask according to the present invention, a plurality of metal thin films are fixed to the frame body while applying tension to the frame body, and then a plurality of metal thin films are formed as in the prior art by forming a transmission hole pattern in the metal thin film. Compared to the case where the transmission hole is formed and then stretched on the frame, the transmission hole is less likely to be displaced in size and position. Accordingly, the plurality of transmission holes are formed in a desired size and shape, and the positional accuracy of the transmission holes in each metal thin film and the relative positional accuracy of the transmission holes between the plurality of metal thin films are ensured.

  The vapor deposition mask according to the present invention has a frame having an opening and a plurality of transmission holes for allowing the vapor deposition material to pass through the frame and covering the opening. And a mask portion where a plurality of metal thin films are welded to each other.

  The manufacturing method of the display apparatus by this invention includes the process of forming the organic layer of an organic light emitting element by vapor deposition using the mask for vapor deposition of this invention.

  In the deposition mask and the display device manufacturing method according to the present invention, the mask portion in which a plurality of metal thin films each having a plurality of transmission holes are welded to each other is supported in a state where tension is applied by a frame. Thus, multiple dimensions can be obtained while ensuring the dimensional accuracy of the plurality of transmission holes, the position system of the transmission holes in the metal thin film, and the relative position accuracy of the transmission holes between the plurality of metal thin films.

  According to the vapor deposition mask manufacturing method of the present invention, a plurality of metal thin films are fixed to a frame while applying tension, and then a plurality of transmission holes are formed in the metal thin film. While being formed in a desired size and shape, the positional accuracy of the transmission holes in each metal thin film and the relative positional accuracy of the transmission holes between the plurality of metal thin films are ensured, and the transmission hole pattern is formed with high accuracy. It becomes possible to realize multi-sided machining.

  According to the vapor deposition mask and display device manufacturing method of the present invention, the plurality of metal thin films each having a plurality of transmission holes are supported while being tensioned by the frame, so that the accuracy of the transmission hole pattern is ensured. On the other hand, it is possible to take multiple faces. Thereby, patterns, such as an organic layer, are formed accurately and efficiently, and a large-sized and highly reliable organic EL display can be manufactured.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  First, the structure of the vapor deposition mask 1 which concerns on one embodiment of this invention is demonstrated with reference to FIGS. FIG. 1A is a perspective view showing a schematic configuration viewed from the side of the metal thin film 10 (hereinafter referred to as the surface side), and FIG. 1B is a side of the frame body 11 of the evaporation mask 1 (hereinafter referred to as the following). It is a perspective view showing the schematic structure seen from the back side. FIG. 2 is a cross-sectional view taken along line II in FIG. FIG. 3 is an enlarged view of the transmission hole 10A-1 (region S1 in FIG. 2).

  The vapor deposition mask 1 is used, for example, when an organic layer of an organic light emitting element is formed in a predetermined pattern by a vacuum vapor deposition method. In the vapor deposition mask 1, a plurality of metal thin films 10 are supported by a frame 11, and the plurality of metal thin films 10 constitute a mask portion. In the present embodiment, during film formation, for example, a vapor deposition source is disposed on the side of the metal thin film 10 facing the frame 11 (hereinafter referred to as the back surface side) and faces the frame 11 of the metal thin film 10. An element substrate (deposition substrate) or the like is arranged and used on the non-side (hereinafter referred to as the front side).

  The metal thin film 10 is fixed to the frame 11 in a state where a predetermined tension T is applied so as to cover an opening 11A (described later) of the frame 11, and corresponds to the opening 11A of the frame 11. The region has a transmission hole pattern 10A in which a plurality of transmission holes 10A-1 are arranged. Thus, by applying the tension T, each metal thin film 10 is fixed to the frame 11 without wrinkles or slack. Note that the tension T applied to the metal thin film 10 is set to a magnitude and direction in which the amount of strain generated in the metal thin film 10 due to thermal stress due to radiant heat during vapor deposition is offset by the amount of strain generated in the metal thin film 10 due to the tension T. It is preferable. This is because the thermal expansion of the metal thin film 10 during vapor deposition can be absorbed and the positional accuracy of the transmission hole 10A-1 can be increased. A region where the transmission hole pattern 10 </ b> A is formed is an effective vapor deposition region of the vapor deposition mask 1. Such a metal thin film 10 is preferably composed of a metal thin film having a low coefficient of thermal expansion, such as an invar material, a metal or alloy such as nickel (Ni) or copper (Cu), or rolled stainless steel. 10 μm to 50 μm.

  In the transmission hole pattern 10A, for example, a plurality of transmission holes 10A-1 are formed corresponding to a pattern such as a deposited organic light emitting layer. As shown in FIG. 3, the transmission hole 10 </ b> A- 1 is formed such that the opening area of the back surface side opening 100 </ b> B is larger than the opening surface 100 </ b> A on the front surface side. With such a configuration, the vapor deposition material is transmitted from the back side to the front side.

  The frame 11 is made of, for example, Invar material, and has a thickness of, for example, 5 mm to 30 mm. The frame 11 has a plurality of openings 11A in a lattice shape, for example. Moreover, it is preferable to be comprised with the material which has a linear thermal expansion coefficient equivalent to the drive substrate 15 in which the below-mentioned organic layer is formed. This is because the frame body 11 and the driving substrate 15 can be expanded and contracted in synchronization with the temperature change during vapor deposition, and the amount of dimensional change due to expansion and contraction can be made equal. Further, the frame body 10 has high rigidity and sufficient thickness, and in addition to the linear thermal expansion coefficient, the heat flow, the radiation emission rate of the surface, and heat conduction with the surrounding support body (not shown) are transferred into and out of the frame body 10. It is desirable that the heat amount and the inflow heat amount limited by a heat insulating plate (not shown) that shields radiant heat from a vapor deposition source (not shown) are optimally adjusted. In the present embodiment, a configuration in which four openings 11A and four metal thin films 10 (transmission hole patterns 10A) are formed correspondingly will be described as an example.

  Next, the manufacturing method of the vapor deposition mask 1 which has such a structure is demonstrated with reference to FIGS. 4 shows a stretching process for fixing a plurality of metal thin films to a frame while applying tension, FIGS. 5 and 6 show a process for applying a photoresist film, FIG. 7 shows an exposure process, and FIG. 9 shows a development and etching process. Each is represented in the order of steps. FIG. 8 is a plan view showing an example of an exposure pattern in the exposure step of FIG.

  First, as shown in FIG. 4A, after the metal thin film 10 is overlaid on the frame body 11 so as to cover the opening 11A of the frame body 11 with a constant tension T applied thereto, As shown in FIG. 4B, the frame 11 is fixed to the periphery of the opening 11A of the frame 11 by, for example, spot welding or seamless welding. At this time, for example, a polyester mesh is fixed to a rectangular screen frame member with tension, and the periphery of the metal thin film 10 is bonded to the polyester mesh with an adhesive, and then the inside of the polyester mesh, that is, the metal thin film 10 is opposed. By cutting the region, a tension T is applied to the metal thin film 10 with the in-plane direction as a main component. Similarly, for example, four metal thin films 10 are fixed by welding so as to correspond to each of the four openings 11 of the frame 11.

  Next, as shown in FIG. 5A, coating is performed by spraying, for example, by spraying the spray nozzle 120 and pitching the frame 11 or the spray nozzle 120 in a direction perpendicular to the paper surface. As a result, a photoresist film (photosensitive resin) 12 a is formed on the surface side of the metal thin film 10. After that, it is pre-baked and dried. Subsequently, as shown in FIG. 5B, the frame 11 to which the metal thin film 10 is fixed is turned upside down, and a photoresist film 12b is formed on the back side of the metal thin film 10 from the frame 11 side. And pre-baked and dried. In this manner, the photoresist films 12a and 12b are formed on both the front surface side and the back surface side of the metal thin film 10.

  Next, as shown in FIG. 6A, in the subsequent process, in order to prevent the intrusion of the etchant, the metal thin film 10 is formed on the boundary portion where the metal thin film 10 and the frame 11 are overlapped. From the back surface side, a stopper (13) is formed by applying and drying a thicker photoresist (more solid content) than the photoresist films 12a and 12b using the dispenser 121 or the like. Subsequently, as shown in FIG. 6B, the frame 11 is turned upside down, and the sealing portion 13 is formed in the same manner as described above for the region between the adjacent metal thin films 10.

  Next, as shown in FIG. 7A, the metal thin film 10 and the frame 11 coated with the photoresist films 12a and 12b are set in the laser direct exposure machine 122, and the surface side of the metal thin film 10 is exposed. Scan and draw a desired pattern. Subsequently, as shown in FIG. 7B, the metal thin film 10 and the frame 11 are turned upside down, aligned with the previous pattern, the back side of the metal thin film 10 is exposed, and a desired pattern is scanned. draw. At this time, the exposure pattern data is set so that the opening area of the transmission hole 10A-1 formed in the metal thin film 10 is larger on the back side than on the front side. In addition, as shown in FIG. 8, the planar shape of the exposure pattern at this time is an exposure pattern 14 having a shape in which the central portions of the four sides of the quadrangle are curved inward.

  Next, as shown in FIG. 9A, the photoresist films 12a and 12b are developed to expose portions of the metal thin film 10 to be etched. Subsequently, as shown in FIG. 9B, etching is performed on both surfaces of the metal thin film 10 using an etchant such as ferric chloride. After that, the photoresist films 12a and 12b are peeled off and washed with water and dried to form a through hole pattern 10A in each metal thin film 10, thereby completing the vapor deposition mask 1 shown in FIGS.

  As described above, in the method of manufacturing the evaporation mask 1 according to the present embodiment, the plurality of metal thin films 10 are fixed to the frame 11 while applying tension, and then the plurality of transmission hole patterns 10A are formed. Thus, as compared with the conventional case where the plurality of metal thin films are fixed to the frame after the formation of the transmission hole pattern, the size and position of the transmission holes 10A-1 are less likely to be displaced. In the conventional method, when a tension is applied, stress is applied to the transmission hole, so that the accuracy of the metal thin film alone is lowered. In addition, when performing multi-chamfering using a plurality of metal thin films, it is difficult to apply a tension T with a certain magnitude and direction to each metal thin film. The relative positional accuracy will be reduced. On the other hand, in this embodiment, since the transmission hole 10A-1 is formed after the tension T is applied to each metal thin film 10, the transmission hole 10A-1 in the metal thin film 10 alone is formed. In addition to the dimensional accuracy and the positional accuracy, it is easy to ensure the relative positional accuracy of the transmission holes 10A-1 among the plurality of metal thin films 10. Therefore, it is possible to realize multi-cavity while accurately forming the transmission hole pattern 10A.

  Further, by forming the photoresist films 12a and 12b on both surfaces of the metal thin film 10 by using the spray coating method, unevenness caused by bonding the plurality of metal thin films 10 and the frame body 11, that is, The photoresist films 12a and 12b can be efficiently formed even with respect to the gap formed between the adjacent metal thin films 10 on the front surface side and the step formed by the frame body 11 on the back surface side.

  Here, the conventional technique of drawing an exposure pattern by contact exposure using a photomask does not have flexibility for changing the mask size. Further, when a plurality of metal thin films are fixed to the frame for multi-cavity processing, as described above, unevenness is generated, so that it is difficult to ensure adhesion with the photomask. In contrast, in this embodiment, since the direct exposure method using laser is used, an exposure pattern can be directly drawn in a desired shape at a desired position of the photoresist films 12a and 12b. It is also possible to dynamically correct pattern dimensions and shapes. Therefore, even when unevenness is caused by laminating a plurality of metal thin films and a frame body in multi-chamfering, the dimensional accuracy and position accuracy of the transmission hole pattern 10A can be effectively ensured.

  Further, the through-hole pattern 10A may be deformed because the apparent Young's modulus of the metal thin film 10 is lowered after etching. For this reason, the exposure pattern 14 has a shape that is curved inward at the center portion of the quadrangle as shown in FIG. 8, that is, the deformation amount is analyzed in advance, and the deformation amount is estimated and corrected. If it is set as the shape which applied *, the more accurate through-hole pattern 10A can be formed.

  By the way, in order to transmit the vapor deposition material from the vapor deposition source uniformly, the transmission hole 10A-1 has an opening on the vapor deposition source side (the back surface side in the present embodiment), and the deposition side (the front surface side in the present embodiment). It is preferable to reduce the shadowing effect that the vapor deposition material incident obliquely from the vapor deposition source becomes a shadow of the opening and becomes difficult to adhere (shadow effect). For this reason, in the conventional photoetching method that does not use laser direct exposure, means such as taper etching must be used to incline the edge of the transmission hole, and fine adjustment is required in the etching process. It is difficult to ensure etching accuracy.

  On the other hand, if the exposure pattern data is set by the laser direct exposure method so that the opening area is larger on the back surface side than the front surface side of the transmission hole 10A-1 as in the present embodiment. The transmission hole 10A-1 having a cross-sectional shape as shown in FIG. 3 can be easily formed without fine adjustment in the etching process. Therefore, for example, when an evaporation source is disposed on the back surface side and an organic layer or the like is evaporated on the element substrate, for example, the above-described shadow effect is reduced, so that the film can be accurately formed with a uniform film thickness. become.

  Next, a display device 2 that can be manufactured using the vapor deposition mask 1 as described above will be described with reference to FIG. FIG. 10 is a cross-sectional view illustrating a schematic configuration of the display device 2.

  The display device 2 includes an organic light emitting element 14R that generates red light, an organic light emitting element 14G that generates green light, and an organic light emitting element 14B that generates blue light as a whole in a matrix. It is configured. The organic light emitting elements 14R, 14G, and 14B are respectively provided with a first electrode 16 as an anode, an insulating film 17, a hole injection layer 18, a hole transport layer 19, a light emitting layer, and an electron transport layer from the driving substrate 15 side. 21 and a second electrode 22 as a cathode are stacked in this order. However, as the light emitting layer, a red light emitting layer 20R, a green light emitting layer 20G, and a blue light emitting layer 20B corresponding to each of the organic light emitting elements 14R, 14G, and 14B are formed. These red light emitting layer 20R, green light emitting layer 20G, and blue light emitting layer 20B can be suitably patterned using the vapor deposition mask 1 according to the present embodiment.

  Such organic light-emitting elements 14R, 14G, and 14B are covered with a protective film 23 such as silicon nitride (SiN) or silicon oxide (SiO) as necessary, and a thermosetting resin is further formed on the protective film 23. Alternatively, sealing is performed by bonding a sealing substrate 25 made of glass or the like across the entire surface with an adhesive layer 24 such as an ultraviolet curable resin in between.

  The first electrode 16 is formed corresponding to each of the organic light emitting elements 14R, 14G, and 14B. In addition, the first electrode 16 has a function as a reflective electrode that reflects light generated in the light emitting layer, and it is desirable that the first electrode 16 has a reflectance as high as possible in order to increase luminous efficiency. For example, the first electrode 16 has a thickness of 100 nm to 1000 nm, and is silver (Ag), aluminum (Al), chromium (Cr), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni ), Molybdenum (Mo), copper (Cu), tantalum (Ta), tungsten (W), platinum (Pt), gold (Au), or the like.

The insulating film 17 is formed in a region between the adjacent first electrodes 16 to ensure insulation between the first electrodes 16 and between the first electrode 16 and the second electrode 22, so that the light emitting region can be accurately defined. It has a function as an interelectrode insulating film for obtaining a desired shape. The insulating film 17 is made of, for example, an organic material such as polyimide, or an inorganic insulating material such as silicon oxide (SiO ₂ ), and has an opening corresponding to the light emitting region of the first electrode 16. The light emitting layer may be continuously provided not only on the light emitting region but also on the insulating film 17, but light emission occurs only in the opening corresponding to the first electrode 16 of the insulating film 17. .

  The hole injection layer 18, the hole transport layer 19, and the electron transport layer 21 are layers common to the organic light emitting devices 14R, 14G, and 14B. The hole injection layer 18, the hole transport layer 19, and the electron transport layer 21 may be provided as necessary and may have different configurations depending on the emission color.

  The hole injection layer 18 is a buffer layer for improving hole injection efficiency and preventing leakage. The hole injection layer 18 has, for example, a thickness of 5 nm to 300 nm, for example, 25 nm, and is 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (m-MTDATA) or 4, It is composed of 4 ′, 4 ″ -tris (2-naphthylphenylamino) triphenylamine (2-TNATA).

  The hole transport layer 19 is for increasing the efficiency of hole transport to the red light emitting layer 20R, the green light emitting layer 20G, and the blue light emitting layer 20B. The hole transport layer 19 has, for example, a thickness of 5 nm to 300 nm, for example, 30 nm, and is composed of 4,4′-bis (N-1-naphthyl-N-phenylamino) biphenyl (α-NPD). Yes.

  The red light emitting layer 20R has, for example, a thickness of 10 nm or more and 100 nm or less, and 9,10-di- (2-naphthyl) anthracene (ADN) with 2,6≡bis [4′≡methoxydiphenylamino) styryl] ≡1. , 5≡dicyanonaphthalene (BSN) mixed with 30% by weight. The green light emitting layer 20G has a thickness of, for example, 10 nm or more and 100 nm or less, and is configured by mixing 5% by volume of coumarin 6 with ADN. The blue light emitting layer 20B has, for example, a thickness of 10 nm or more and 100 nm or less, and 2,4′≡bis [2≡ {4≡ (N, N≡diphenylamino) phenyl} vinyl] biphenyl (DPAVBi) is added to ADN. It is composed of a mixture of 5% by weight.

The electron transport layer 21 has, for example, a thickness of 20 nm and is made of 8-hydroxyquinoline aluminum (Alq ₃ ). Note that an electron injection layer made of, for example, LiF, Li ₂ O, or the like may be provided between the electron transport layer 21 and a second electrode 22 described later in order to increase electron injection efficiency.

  The second electrode 22 has, for example, a thickness of 5 nm to 50 nm, and a simple substance or an alloy of a metal element such as aluminum (Al), magnesium (Mg), calcium (Ca), sodium (Na), or ITO (indium. It may be composed of a transparent electrode material such as tin composite oxide) or IZO (indium / zinc composite oxide).

  Such a display device 2 can be manufactured as follows, for example.

  First, the first electrode 16 made of the above-described material is formed on the planarized driving substrate 15 by, for example, sputtering, and is formed into a predetermined shape by, for example, etching. Next, the insulating film 17 made of the above-described material is formed by, for example, photolithography. At this time, an opening is provided corresponding to the light emitting region of the first electrode 16. Thereafter, the hole injection layer 18 and the hole transport layer 19 made of the above-described materials are formed on the first electrode 16 and the insulating film 17 by using, for example, a vapor deposition method, a CVD method, a printing method, an inkjet method, a transfer method, or the like. Form on top.

  Next, the red light emitting layer 20R, the green light emitting layer 20G, and the blue light emitting layer 20B are formed on the element regions corresponding to the respective colors on the formed hole transport layer 19 by using the vapor deposition mask 1 according to the present embodiment. The pattern is formed by vapor-depositing. Thereafter, the electron transport layer 21 and the second electrode 22 made of the above-described materials are sequentially formed by, for example, a vapor deposition method, a sputtering method, a CVD method, or the like so as to cover the formed color light emitting layers. Finally, a protective film 23 made of the above-described material is formed on the second electrode 22 by, for example, vapor deposition, sputtering, CVD, or the like, and sealed with an adhesive layer 24 in between. The substrate 25 is bonded. Thus, the display device 2 shown in FIG. 10 is completed.

  Thus, in the manufacturing method of the display device 2, the red light emitting layer 20R, the green light emitting layer 20G, and the blue light emitting layer 20B are patterned by vapor deposition using the vapor deposition mask 1, so that the pattern of each color light emitting layer is changed. It is accurately formed at a desired position with a uniform film thickness. Therefore, the reliability of the display device 2 is improved.

  Next, a modified example of the present invention will be described. In the following, the same components as those of the vapor deposition mask 1 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

(Modification 1)
FIG. 11 is a cross-sectional view illustrating a schematic configuration of a vapor deposition mask 3 according to Modification 1 of the present invention. In the evaporation mask 3, a plurality of metal thin films 10 are connected to each other by a connection plate 22, and tension is applied to the plurality of metal thin films 10. In the present modification, these joined metal thin films 10 constitute a mask portion, and only the peripheral portion of the mask portion is fixed to the frame body 21. That is, the through hole pattern 10 </ b> A of the plurality of metal thin films 10 is provided in a region corresponding to one opening 21 </ b> A of the frame body 21. Such a vapor deposition mask 3 can be manufactured through the same process as the vapor deposition mask 1 except for the tensioning process in which the plurality of metal thin films 10 are fixed to the frame body 21 while applying tension. it can.

  In the stretching step of the deposition mask 3, first, the end portions of the metal thin films 10 are joined from the back side by the connection plate 22, and then tension is applied to the whole. While being fixed to the frame body 21. At this time, as a method for joining the metal thin film 10 and the connection plate 22, for example, spot welding, seamless welding, or the like can be used. In addition, as the connection plate 22, for example, an invar material, a stainless steel plate, or the like can be used, and the thickness is, for example, 50 μm to 500 μm. Thereafter, the deposition mask 3 is completed by performing the above-described exposure, development, and etching steps.

  As described above, after the plurality of metal thin films 10 are connected by the connection plate 22 for connecting to each other, they may be fixed to the frame body 21 while applying tension. Thereby, the frame body 21 should just have one opening part 21A as a whole, and it becomes unnecessary to provide a grid-like crosspiece. Therefore, since the vapor deposition shadow effect by the frame portion can be reduced, the pitch between the transmission hole patterns 10A can be further narrowed, and the effective vapor deposition area can be increased. Further, since the tension can be averaged as compared with the case where the metal thin films are individually stretched, the positional accuracy of the transmission hole pattern 10A can be further improved.

(Modification 2)
FIG. 12 is a cross-sectional view illustrating a schematic configuration of a vapor deposition mask 4 according to Modification 2 of the present invention. The vapor deposition mask 4 is bonded in a state where the ends of the plurality of metal thin films 10 are overlapped (bonding portion 23), and tension is applied to the plurality of metal thin films 10. In the present modification, the plurality of bonded metal thin films 10 constitute a mask portion, and only the peripheral portion of the mask portion is fixed to the frame body 21. That is, similarly to the first modification, the transmission port patterns 10A of the plurality of metal thin films 10 are provided in the region corresponding to the opening 21A of the frame body 21. Such a vapor deposition mask 4 can be manufactured through the same process as the vapor deposition mask 1 except for a tensioning process in which a plurality of metal thin films are fixed to the frame body 21 while applying tension. .

  In the stretching step of the vapor deposition mask 4, first, a plurality of metal thin films 10 are bonded together by overlapping their end portions, and then a frame is applied while applying tension to the whole. It is made to adhere to 21. At this time, as a method for joining the metal thin films, for example, spot welding, seamless welding, or the like can be used. Thereafter, the deposition mask 4 is completed by performing the above-described exposure, development, and etching steps.

  As described above, the plurality of metal thin films 10 may be bonded to each other by directly bonding the ends thereof, and then fixed to the frame body 21 while applying tension. Thereby, the effect similar to the said modification 1 can be acquired.

(Modification 3)
FIG. 13 is a perspective view showing a schematic configuration of a vapor deposition mask 5 according to Modification 3 of the present invention. The vapor deposition mask 5 is the same as the vapor deposition mask 1 except that a stress relaxation region 26 for stress relaxation is further formed in a region around the transmission hole pattern 10A formed in the metal thin film 24. It has a configuration. The stress relaxation region 26 has a configuration in which a plurality of pores 26A are arranged in a trapezoidal region having, for example, a side opposite to the transmission hole pattern 10A as a base (lower base). Such a stress relaxation region 26 can be formed at the same time, for example, in the step of forming the transmission hole pattern 10A after the metal thin film is fixed to the frame 11 while applying tension.

  However, in the configuration of FIG. 13, an example is shown in which a total of four trapezoidal stress relaxation regions 26 are formed on two opposing sides of the transmission hole pattern 10 </ b> A, but the configuration of the stress relaxation region 26 is limited to this. It is not something. For example, the stress relaxation region may be provided in all the regions facing the four sides of the transmission hole pattern 10A. Further, the shape of the stress relaxation region is not limited to the trapezoidal shape, and may be another shape, for example, a triangular shape having a side facing the transmission hole pattern 10A as a base.

  As described above, by providing the stress relaxation region 26 in the peripheral region of the transmission hole pattern 10A that is an effective vapor deposition region of the metal thin film 10, the stress changes due to, for example, etching in a later process, and the transmission hole pattern 10A at the time of exposure. When the deformation occurs, the stress applied to the transmission hole pattern 10A is relaxed, so that the transmission hole pattern 10A can be maintained with higher accuracy.

(Modification 4)
14-17 is for demonstrating the manufacturing method of the mask 6 for vapor deposition which concerns on the modification 4 of this invention. In this method of manufacturing the evaporation mask 6, it can be manufactured in the same manner as the evaporation mask 1 except that the front and back surfaces of the metal thin film 30 are etched on each side.

  First, after fixing the metal thin film 30 to the frame 11 with respect to the metal thin film 30 in the same procedure as in the steps of FIGS. 4 to 6 described above, the photoresist films 12a-1, 12b-1 and the sealing portion 13 is formed. Thereafter, a desired pattern is drawn only on the surface side of the metal thin film 30 by the above-described laser direct exposure method, and only the photoresist film 12a-1 on the surface side of the metal thin film 30 is developed (FIG. 14A). )). Subsequently, as shown in FIG. 14B, half etching is performed from the surface side of the metal thin film 30. Subsequently, as shown in FIG. 14C, the photoresist films 12a-1, 12b-1 and the sealing portion 13 are once peeled off and washed with water and dried.

  Next, as shown in FIG. 15A, after forming a photoresist film 12a-2 on the surface side of the metal thin film 30 by spray coating, as shown in FIG. A photoresist film 12b-2 is formed from the back side of the metal thin film 30 by spray coating. The sealing portion 13 is also formed in the vicinity of the boundary between the metal thin film 30-1 and the frame 11 and the gap between the metal thin films 30.

  Next, as shown in FIG. 16A, a desired pattern is drawn on the back surface side of the metal thin film 30 by the laser direct exposure method described above. At this time, the exposure pattern data is set so that the opening area of the transmission hole on the back surface side is larger than that on the front surface side. Subsequently, as shown in FIG. 16B, the photoresist film 12b-2 on the back surface side of the metal thin film 30 is developed.

  Next, as shown in FIG. 17A, etching is performed until the metal thin film 30 penetrates from the back surface side toward the front surface side. Finally, as shown in FIG. 17B, the photoresist films 12a-2, 12b-2 and the sealing portion 13 are peeled off, washed with water, and dried to thereby provide the evaporation mask 6 having the transmission hole pattern 30A. To complete. The transmission hole 30A-1 of the transmission hole pattern 30A thus formed has a cross-sectional shape as shown in FIG. FIG. 18 is an enlarged view of the region S2 in FIG.

  In this way, the transmission hole pattern 30A can be formed by performing etching on each side. Since it is possible to perform precise etching by performing etching from the lower side rather than from the upper side, the accuracy can be further improved by performing etching only from the lower side.

(Modification 5)
FIGS. 19-21 is for demonstrating the manufacturing method of the mask 7 for vapor deposition which concerns on the modification 5 of this invention. In this method of manufacturing the evaporation mask 7, the metal thin film 40 can be manufactured in the same manner as the evaporation mask 1 except that the metal thin film 40 is etched in multiple stages.

  First, the metal thin film 40 is fixed to the frame 11 in the same procedure as the steps of FIGS. Thereafter, the surface side of the metal thin film 40 is half-etched in the same procedure as the steps of FIGS. 14 to 16 of the vapor deposition mask 6 described above, and then the photoresist films 12 a-2, 12 b-2 and the sealing portion 13. The exposure pattern is drawn and the photoresist film 12b-2 is developed.

  Next, as shown in FIG. 19A, etching is performed from the back surface side to the front surface side of the metal thin film 40, and is stopped immediately before penetrating. Subsequently, as shown in FIG. 19B, the photoresist films 12a-2, 12b-2 and the sealing portion 13 are peeled off, and are washed with water and dried.

  Next, after the photoresist films 12a-3 and 12b-3 are formed on the front surface side and the back surface side of the metal thin film 40 by the above-described spray coating method, as shown in FIG. On the side photoresist film 12b-3, an exposure pattern is drawn by the laser direct exposure method described above. Subsequently, as shown in FIG. 20B, the photoresist film 12b-3 is developed.

  Next, as shown in FIG. 21A, etching is performed until the metal thin film 40 penetrates from the back surface side toward the front surface side. Finally, as shown in FIG. 21 (B), the photoresist films 12a-3, 12b-3 and the sealing portions 13 are peeled off, washed with water, and dried, whereby a vapor deposition mask 7 having a transmission hole pattern 40A. To complete. The transmission hole 40A-1 of the transmission hole pattern 40A thus formed has a cross-sectional shape as shown in FIG. Note that FIG. 22 is an enlarged view of the region S3 in FIG.

  Thus, the transmission hole pattern 40A can be formed by performing multi-step etching. Thereby, since the inclination of the cross section on the back surface side can be increased, the vapor deposition shadow effect can be reduced.

(Application examples and modules)
Hereinafter, a module and an application example of the display device 2 described in the above-described embodiment will be described. The display device 2 is a television device, a digital still camera, a notebook personal computer, a portable terminal device such as a mobile phone, or a video camera. The display device 2 uses an externally input video signal or an internally generated video signal as an image or video. The present invention can be applied to display devices for electronic devices in all fields for display.

(module)
The display device 2 is incorporated into various electronic devices such as application examples 1 to 5 described later, for example, as a module shown in FIG. In this module, a region 210 exposed from the sealing substrate 25 is provided on one side of the driving substrate 15, and wiring of a signal line driving circuit 120 and a scanning line driving circuit 130 to be described later is extended to the region 210 for external connection. A terminal (not shown) is formed. The external connection terminal may be provided with a flexible printed circuit (FPC) 220 for signal input / output.

  For example, as shown in FIG. 24, the drive substrate 15 is formed with a display area 110, a signal line drive circuit 120 that is a video display driver, and a scanning line drive circuit. A pixel drive circuit 140 is formed in the display area 110. In the display area 110, the organic light emitting elements 14R, 14G, and 14B are arranged in a matrix as a whole. The organic light emitting elements 14R, 14G, and 14B have a rectangular planar shape, and a combination of adjacent organic light emitting elements 14R, 14G, and 14B constitutes one pixel.

  As shown in FIG. 25, the pixel driving circuit 140 is formed below the first electrode 16, and includes a driving transistor Tr1 and a writing transistor Tr2, a capacitor (holding capacity) Cs therebetween, and a first power supply line (Vcc). And an organic light emitting element 10R (or 10G, 10B) connected in series to the drive transistor Tr1 between the second power supply line (GND). The driving transistor Tr1 and the writing transistor Tr2 are configured by a general thin film transistor (TFT (Thin Film Transistor)), and the configuration may be, for example, an inverted staggered structure (so-called bottom gate type) or a staggered structure (top gate type). There is no particular limitation.

  In the pixel driving circuit 140, a plurality of signal lines 120A are arranged in the column direction, and a plurality of scanning lines 130A are arranged in the row direction. An intersection between each signal line 120A and each scanning line 130A corresponds to one of the organic light emitting elements 10R, 10G, and 10B (sub pixel). Each signal line 120A is connected to the signal line drive circuit 120, and an image signal is supplied from the signal line drive circuit 120 to the source electrode of the write transistor Tr2 via the signal line 120A. Each scanning line 130A is connected to the scanning line driving circuit 130, and a scanning signal is sequentially supplied from the scanning line driving circuit 130 to the gate electrode of the writing transistor Tr2 via the scanning line 130A.

(Application example 1)
FIG. 26 illustrates an appearance of a television device to which the display device 2 of the above embodiment is applied. The television apparatus has, for example, a video display screen unit 300 including a front panel 310 and a filter glass 320, and the video display screen unit 300 is configured by the display device 2.

(Application example 2)
FIG. 27 shows the appearance of a digital still camera to which the display device 2 of the above embodiment is applied. The digital still camera includes, for example, a flash light emitting unit 410, a display unit 420, a menu switch 430, and a shutter button 440, and the display unit 420 includes the display device 2.

(Application example 3)
FIG. 28 shows the appearance of a notebook personal computer to which the display device 2 of the above embodiment is applied. The notebook personal computer has, for example, a main body 510, a keyboard 520 for inputting characters and the like, and a display unit 530 that displays an image. The display unit 530 is configured by the display device 2. .

(Application example 4)
FIG. 29 shows the appearance of a video camera to which the display device 2 of the above embodiment is applied. This video camera has, for example, a main body 610, a subject photographing lens 620 provided on the front side surface of the main body 610, a start / stop switch 630 at the time of photographing, and a display 640. Reference numeral 640 denotes the display device 2.

(Application example 5)
FIG. 30 shows an appearance of a mobile phone to which the display device 2 of the above embodiment is applied. For example, the mobile phone is obtained by connecting an upper housing 710 and a lower housing 720 with a connecting portion (hinge portion) 730, and includes a display 740, a sub-display 750, a picture light 760, and a camera 770. Yes. The display 740 or the sub display 750 is configured by the display device 2.

  While the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, when forming the through hole pattern of the metal thin film, the metal thin film and the frame body are turned upside down for each process, and the photoresist film is applied and exposed alternately on the front surface side and the back surface side. However, the order in which the respective steps are performed on the front surface side or the back surface side is not particularly limited, and the processing may be performed from either the front surface side or the back surface side.

  In the above embodiment, the vapor deposition source is arranged on the back surface side of the vapor deposition mask and the vapor deposition material is transmitted from the back surface side to the front surface side of the transmission hole. Instead, a reverse configuration, that is, a configuration in which a vapor deposition source is disposed on the front surface side of the vapor deposition mask and the vapor deposition material is transmitted from the front surface side to the back surface side of the transmission hole may be employed. However, in this case, it is desirable to set the exposure pattern so that the opening area of the transmission hole is smaller on the back side than on the front side.

  Moreover, in the said embodiment, although demonstrated taking the case of the structure which fixed four metal thin films with respect to the frame, it is not limited to this, The structure which fixed at least two metal thin films to the frame Then, the effect of the present invention is achieved. Conversely, a configuration in which five or more metal thin films are fixed may be used. Further, the through-hole pattern of the metal thin film, the number of the through-holes and the arrangement configuration are not limited to the above embodiment, but can be appropriately set based on the pattern configuration on the element substrate to be deposited. is there.

  Moreover, in the said embodiment, in the manufacturing method of the display apparatus 2, only the red light emitting layer 20R, the green light emitting layer 20G, and the blue light emitting layer 20B of the organic light emitting elements 14R, 14G, and 14B are formed using the vapor deposition mask 1. However, the present invention is not limited to this, and other organic layers such as a hole injection layer, a hole transport layer, and an electron transport layer are also deposited using the deposition mask of the present invention. Can be formed.

  In the above embodiment, the case of an active matrix display device has been described. However, the present invention can also be applied to a passive matrix display device. Furthermore, the configuration of the pixel driving circuit for active matrix driving is not limited to that described in each of the above embodiments, and a capacitor or a transistor may be added as necessary. In that case, a necessary driving circuit may be added in addition to the signal line driving circuit 120 and the scanning line driving circuit 130 described above in accordance with the change of the pixel driving circuit.

  Further, in the above embodiment, the case where the first electrode 16 of the organic light emitting element is the anode and the second electrode 22 is the cathode has been described. However, the anode and the cathode are reversed, the first electrode 16 is the cathode, The electrode 22 may be an anode. Further, the first electrode 16 is a cathode and the second electrode 22 is an anode, and the second electrode 22, the organic layer 16, and the first electrode 16 are sequentially stacked on the substrate 11 from the substrate 11 side. It is also possible to extract light from the side.

It is a perspective view showing schematic structure of the mask for vapor deposition which concerns on one embodiment of this invention. It is sectional drawing showing the schematic structure of the mask for vapor deposition shown in FIG. FIG. 3 is an enlarged view of a transmission hole of the vapor deposition mask shown in FIG. 2. It is sectional drawing showing the manufacturing method of the vapor deposition mask shown in FIG. 1 in order of a process. FIG. 5 is a cross-sectional view illustrating a process following FIG. 4. FIG. 6 is a cross-sectional view illustrating a process following FIG. 5. FIG. 7 is a cross-sectional view illustrating a process following FIG. 6. It is sectional drawing showing schematic structure of the wiring structure shown in FIG. FIG. 9 is a cross-sectional diagram illustrating a process following the process in FIG. 8. It is sectional drawing showing schematic structure of the display apparatus which can be manufactured using the mask for vapor deposition shown in FIG. It is sectional drawing showing schematic structure of the mask for vapor deposition which concerns on the modification 1 of this invention. It is sectional drawing showing schematic structure of the mask for vapor deposition which concerns on the modification 2 of this invention. It is a perspective view showing schematic structure of the vapor deposition mask which concerns on the modification 3 of this invention. It is sectional drawing showing the manufacturing method of the mask for vapor deposition which concerns on the modification 4 of this invention in order of a process. FIG. 15 is a cross-sectional view illustrating a process following FIG. 14. FIG. 16 is a cross-sectional diagram illustrating a process following the process in FIG. 15. FIG. 17 is a cross-sectional diagram illustrating a process following the process in FIG. 16. It is an enlarged view of the transmission hole of the mask for vapor deposition which concerns on the modification 4 of this invention. It is sectional drawing showing the manufacturing method of the vapor deposition mask which concerns on the modification 5 of this invention in order of a process. FIG. 20 is a cross-sectional diagram illustrating a process following the process in FIG. 19. FIG. 21 is a cross-sectional diagram illustrating a process following the process in FIG. 20. It is an enlarged view of the transmission hole of the mask for vapor deposition which concerns on the modification 5 of this invention. It is a top view showing schematic structure of the module containing the display apparatus of this Embodiment. FIG. 24 is a plan view illustrating a configuration of a drive circuit of the display device in the module illustrated in FIG. 23. FIG. 25 is an equivalent circuit diagram illustrating an example of the pixel drive circuit illustrated in FIG. 24. It is a perspective view showing the external appearance of the example 1 of application of the display apparatus of this Embodiment. It is a perspective view showing the external appearance of the example 2 of application of the display apparatus of this Embodiment. It is a perspective view showing the external appearance of the example 3 of application of the display apparatus of this Embodiment. It is a perspective view showing the external appearance of the application example 4 of the display apparatus of this Embodiment. It is a perspective view showing the external appearance of the application example 5 of the display apparatus of this Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,3,4,5,6,7 ... Evaporation mask, 2 ... Display apparatus, 10, 20, 30, 40 ... Metal thin film, 11, 21 ... Frame, 12a, 12a-1, 12a-2, 12a -3, 12b, 12b-1, 12b-2, 12b-3, 13 ... photoresist film, 14R, 14G, 14B ... organic light emitting element, 15 ... driving substrate, 16 ... first electrode, 17 ... insulating film, DESCRIPTION OF SYMBOLS 18 ... Hole injection layer, 19 ... Hole transport layer, 20R ... Red light emitting layer, 20G ... Green light emitting layer, 20B ... Blue light emitting layer, 21 ... Electron transport layer, 22 ... Second electrode, 23 ... Protective film, 24 ... adhesive layer, 25 ... sealing substrate.

Claims (16)

A tensioning step of fixing a plurality of metal thin films for a mask to a frame having an opening while applying tension so as to cover the opening;
A method of manufacturing a vapor deposition mask, comprising: forming a plurality of transmission holes for transmitting a vapor deposition material in a plurality of metal thin films fixed to the frame. The frame has a plurality of openings,
The stretching step includes
The method for manufacturing an evaporation mask according to claim 1, wherein each metal thin film is fixed to each of the plurality of openings. The stretching step includes
2. The vapor deposition according to claim 1, wherein after overlapping and welding the ends of the plurality of metal thin films, the plurality of metal thin films that are overlapped are fixed to the frame body while applying tension. Mask manufacturing method. The stretching step includes
The ends of the plurality of metal thin films are connected to each other by welding via a connection plate, and the plurality of connected metal thin films are fixed to the frame body while applying tension. Of manufacturing a mask for vapor deposition. The transmission hole forming step includes
Applying a photosensitive resin to the front and back of the metal thin film;
Exposing the surface of the photosensitive resin by direct irradiation with radiation, and drawing a predetermined pattern;
The method for manufacturing a deposition mask according to claim 1, further comprising: forming a plurality of transmission holes in the metal thin film by performing etching based on a pattern drawn on the photosensitive resin. The method for producing a vapor deposition mask according to claim 5, wherein the photosensitive resin is applied by a spray coating method. By applying another photosensitive synthetic resin that is darker than the photosensitive resin in the vicinity of the boundary between the frame and the metal thin film and in the gap between the adjacent metal thin films, 6. A method for producing a vapor deposition mask according to claim 5, wherein a sealing portion for preventing intrusion is formed. The method for manufacturing a vapor deposition mask according to claim 5, wherein the predetermined pattern is a transmission hole pattern that is deformed with the deformation amount estimated in advance. The method for manufacturing a deposition mask according to claim 5, wherein the etching is single-sided etching that is performed on each side of the metal thin film. The said etching is a double-sided etching performed from the both surfaces of the said metal thin film. The manufacturing method of the mask for vapor deposition of Claim 5 characterized by the above-mentioned. The method for manufacturing a deposition mask according to claim 5, wherein the etching is multi-stage etching performed in multiple stages on the metal thin film.
A frame having an opening;
A mask portion that is stretched over the frame so as to cover the opening, and a plurality of metal thin films each having a plurality of transmission holes for allowing the vapor deposition material to pass therethrough are welded together. A vapor deposition mask characterized by comprising: The evaporation mask according to claim 12, wherein the plurality of metal thin films are welded such that end portions thereof are overlapped with each other. The vapor deposition mask according to claim 12, wherein ends of the plurality of metal thin films are welded to each other via a connection plate.
A method of manufacturing a display device having a plurality of organic light emitting elements,
Forming an organic layer of the organic light emitting device by vapor deposition using a vapor deposition mask;
The vapor deposition mask is
A frame having an opening;
A mask portion that is stretched over the frame so as to cover the opening, and a plurality of metal thin films each having a plurality of transmission holes for allowing the vapor deposition material to pass therethrough are welded together. A method for manufacturing a display device, comprising: The vapor deposition mask,
After fixing multiple metal thin films to the frame while applying tension,
The method for manufacturing a display device according to claim 15, wherein the plurality of metal thin films fixed to the frame body are formed by forming a plurality of transmission holes for allowing the vapor deposition material to pass therethrough.

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