阅读说明：本技术 蒸镀掩模、蒸镀方法以及有机el显示装置的制造方法 (Vapor deposition mask, vapor deposition method, and method for manufacturing organic E L display device ) 是由 岸本克彦 崎尾进 于 2017-12-25 设计创作，主要内容包括：通过使用线膨胀系数较小、并且比重小、具有刚性的材料,从而提供一种轻量、且使用了尺寸偏差较小的框架的蒸镀掩模。本实施方式所公开的蒸镀掩模中,其框架(15)通过碳纤维强化塑料(CFRP)形成。(A vapor deposition mask which is lightweight and uses a frame having a small dimensional variation is provided by using a material having a small linear expansion coefficient, a small specific gravity, and rigidity. In the vapor deposition mask disclosed in the present embodiment, the frame (15) is formed of Carbon Fiber Reinforced Plastic (CFRP).)

1. A vapor deposition mask is characterized by comprising:

a mask body on which an opening pattern is formed;

a frame that engages with at least a part of a peripheral portion of the mask main body and holds the mask main body in a certain state;

the frame is formed of carbon fiber reinforced plastic.

2. The vapor deposition mask according to claim 1,

the carbon fiber reinforced plastic is silicon carbide fiber reinforced plastic taking silicon carbide as reinforcing fiber.

3. The vapor deposition mask according to claim 1 or 2,

the frame is formed as a sandwich structure in which a face plate made of carbon fiber reinforced plastic or a metal plate is attached to at least a part of the opposing surface of a columnar core portion having a void enclosed therein.

4. The vapor deposition mask according to claim 3,

the voids of the core are formed into a broad honeycomb structure.

5. The vapor deposition mask according to any one of claims 1 to 4,

the mask body is a hybrid mask formed by bonding a resin film having the opening pattern formed thereon and a metal support layer having an opening formed thereon so as not to block the opening pattern of the resin film.

6. The vapor deposition mask according to any one of claims 1 to 4,

the mask body is a metal mask made of a thin metal plate on which the opening pattern is formed.

7. The vapor deposition mask according to any one of claims 3 to 6,

the frame has a rectangular shape in a frame shape, and the gap is formed from an inner portion surrounded by the frame toward an outer portion of the frame on a side of the frame to which the mask body is joined.

8. The vapor deposition mask according to any one of claims 1 to 7,

the peripheral edge portion of the mask body is joined to the outer peripheral side wall opposite to the inner side of the frame by bending a part of the peripheral edge portion of the mask body.

9. The vapor deposition mask according to any one of claims 3 to 8,

a panel formed of a magnetic metal plate is attached to the entire outer peripheral wall of the frame enclosing the space.

10. The vapor deposition mask according to claim 9,

the void surrounded by the panel is depressurized.

11. The vapor deposition mask according to claim 9,

the interior of the void surrounded by the panel is filled with an inert gas.

12. A vapor deposition method is characterized by comprising the following steps:

a step of disposing a substrate to be vapor-deposited and the vapor deposition mask according to any one of claims 1 to 11 in a superposed manner, and

and depositing the vapor deposition material on the vapor deposition substrate by scattering the vapor deposition material from a vapor deposition source provided at a distance from the vapor deposition mask.

13. A vapor deposition method according to claim 11,

the frame of the vapor deposition mask has a rectangular shape in a shape of a frame, and the vapor deposition substrate and the vapor deposition mask are arranged such that a side of the frame, which is formed by the gap from the inside surrounded by the frame toward the outside of the frame, is located at a vertical position.

14. A method for manufacturing an organic E L display device, comprising:

a step of forming at least a TFT and a first electrode on a support substrate, depositing an organic material on the support substrate by using the deposition method according to claim 12 or 13 to form a laminated film of organic layers, and forming a second electrode on the laminated film.

Technical Field

The present invention relates to a vapor deposition mask and a vapor deposition method for vapor deposition of an organic layer of an organic E L display device, and a method for manufacturing an organic E L display device.

Background

In the production of an organic E L display device, a driving element such as a TFT is formed on a substrate, and an organic layer is laminated on an electrode thereof corresponding to each pixel unit, the organic layer is sensitive to moisture and cannot be etched, for example, as shown in fig. 8, a laminate of an organic layer 80 is formed by arranging a vapor deposition substrate 81 and a vapor deposition mask 82 composed of a mask body 821 and a frame 822 so as to overlap each other, and vapor-depositing an organic material 85a of a vapor deposition source 85 through an opening 821c of the vapor deposition mask 82, and the necessary organic layer 80 is laminated only on an electrode 81a surrounded by an insulating film 81b of a necessary pixel, as shown in fig. 8, the vapor deposition substrate 81 and the vapor deposition mask 82 are not as close as possible, the organic layer 80 is not formed only in a correct region of the pixel, and a display image is easily blurred if the organic material is not only in the correct region of the pixel, and therefore, the magnetic metal support layer 821b is used on the vapor deposition mask 82, and the vapor deposition substrate 81 is sandwiched between the vapor deposition mask 81 fixedly provided on the correct region of the vapor deposition substrate 81, the permanent magnet 84, and the magnetic mask 82, and the magnetic deposition substrate 82, for example, and the magnetic deposition magnet 82 can be applied (see patent literature 1).

Conventionally, a metal mask has been used as the vapor deposition mask, but the use of a mask body 821 of a hybrid type, in which a resin film 821a and a portion of the resin film 821a other than the edge of the opening 821c are supported by a metal support layer 821b, is being studied. The vapor deposition mask 82 makes the mask main body 821 stable and convenient to operate by being fixed to the frame 822 at the peripheral portion of the mask main body 821. In fig. 8, 821d is an opening of the metal support layer 821b, which is formed larger than the opening 821c so as not to block the opening 821c of the resin film 821 a. The peripheral portion of the metal support layer 821b is fixed to a frame (frame) 822 by welding or the like, and the frame 822 is formed of a metal such as invar having a small thermal expansion coefficient.

Disclosure of Invention

Technical problem to be solved by the invention

As described above, the peripheral portion of the mask main body 821 of the vapor deposition mask 82 is joined to the frame 822. However, as is apparent from fig. 8, when evaporation is performed, the frame 822 is closest to the evaporation source 85. Therefore, the temperature of the frame 822 is most likely to increase, and the heat of the heated frame 822 is transmitted to the mask body 821 of the vapor deposition mask 82 and the vapor deposition substrate 81, and the temperature of the vapor deposition substrate 81 is also likely to increase. Since the frame 822 is solid and has a certain weight and thus has a large heat capacity, it is easy to maintain the temperature once it is warmed up. As a result, the temperature of the peripheral portion of the deposition target substrate 81 is more likely to increase than that of the central portion. That is, there is a problem that the deposition target substrate 81 has a difference in thermal expansion and cannot form a uniform organic layer 80.

However, the size of the mother glass used in the conventional manufacturing process of the liquid crystal panel exceeds G10 (about 2880mm × mm), and it is strongly required to further increase the size of the display device of the organic E L, however, it is difficult to increase the substrate size more than G6H in the manufacturing process of the display device of the organic E L, and one of the reasons is the weight of the vapor deposition mask.

Regarding the weight, even with the above-described size of G6H, the weight of the frame is about 80kg, which is close to the limit of conveying the vapor deposition mask by the robot arm and cannot be any heavier than this. However, from the viewpoint of preventing the displacement of the vapor deposition mask and the vapor deposition substrate due to thermal expansion during vapor deposition, the material of the frame of the vapor deposition mask cannot be easily changed. Further, considering that the mask body is already tensioned and bonded, there are some limitations that the frame cannot be made thinner than now.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a vapor deposition mask using a frame having a light weight and a small heat capacity by using a material having a small linear expansion coefficient, a small specific gravity, and rigidity, and a vapor deposition method using the vapor deposition mask.

Another object of the present invention is to provide a method for manufacturing a large organic E L display device having excellent display quality using the above vapor deposition method.

Means for solving the problems

A vapor deposition mask according to a first embodiment of the present invention includes a mask body having an opening pattern formed therein, and a frame bonded to at least a part of a peripheral edge portion of the mask body and holding the mask body in a fixed state, the frame being formed of a carbon fiber-reinforced plastic.

A vapor deposition method according to a second embodiment of the present invention includes a step of placing a vapor deposition substrate and a vapor deposition mask in a stacked state, and a step of depositing a vapor deposition material on the vapor deposition substrate by scattering the vapor deposition material from a vapor deposition source placed at a distance from the vapor deposition mask.

The method of manufacturing an organic E L display device according to the third embodiment of the present invention includes forming at least a TFT and a first electrode on a supporting substrate, forming a laminate film of organic layers by depositing an organic material on the supporting substrate using the evaporation method, and forming a second electrode on the laminate film.

Effects of the invention

According to the invention, the frame of the evaporation mask is formed from Carbon Fibre Reinforced Plastic (CFRP). The frame occupies most of the weight of the vapor deposition mask, but the CFRP has a small specific gravity of less than 2 and a large mechanical strength. Further, the linear expansion coefficient is also small, and is 3 ppm/DEG C or less, and further, by using a sandwich structure having a void, a vapor deposition mask which is lighter in weight and can reduce heat capacity can be obtained. This makes it possible to increase the size of the vapor deposition mask. The Carbon Fiber Reinforced Plastic (CFRP) is made lighter by using, as a frame, a sandwich structure formed of a core having voids and a face sheet made of a metal plate such as invar.

Drawings

Fig. 1A is a schematic plan view of a vapor deposition mask according to an embodiment of the present invention.

FIG. 1B is a cross-sectional view taken along line B-B in FIG. 1A.

Fig. 1C is a view as seen from an arrow C of fig. 1A.

FIG. 2 is a schematic side view of a vapor deposition device.

Fig. 3A is a diagram of another configuration example of the frame of fig. 1A.

Fig. 3B is an enlarged view of a connection portion between the core and the panel of fig. 3A.

Fig. 4 is a diagram of another structural example of the joining of the mask main body and the frame.

Fig. 5 shows the reason why the force in the lateral direction is strong in the case of the honeycomb structure.

Fig. 6A is a diagram illustrating anisotropy in manufacturing a CFRP material by injection molding.

Fig. 6B is a plan view of an example of the honeycomb structure.

Fig. 6C is a perspective view showing the core part of fig. 6B.

Fig. 7A is a diagram illustrating a vapor deposition process in a method for manufacturing an organic E L display device according to an embodiment of the present invention.

Fig. 7B is a diagram showing a state in which organic layers are stacked in the method for manufacturing an organic E L display device according to the embodiment of the present invention.

FIG. 8 is an explanatory view of a conventional deposition process of an organic layer.

Detailed Description

Hereinafter, a vapor deposition mask and a vapor deposition method according to first and second embodiments of the present invention will be described in detail with reference to the drawings. As shown in a plan view, a sectional view taken along line B-B, and a part of a C view of the vapor deposition mask 1 of fig. 1A to 1C, the vapor deposition mask 1 of the present embodiment includes a mask main body 10 in which an opening pattern 11A is formed, and a frame 15 which is joined to at least a part of a peripheral edge portion of the mask main body 10 to hold the mask main body 10 in a fixed state. Wherein the frame 15 is formed by Carbon Fiber Reinforced Plastic (CFRP). Preferably, the material made of carbon fiber reinforced plastic is formed into a sandwich structure 150, and in the sandwich structure 150, a face plate 152 made of CFRP or a metal plate is bonded to an opposing surface of at least a part of a columnar core 151 having a void 151a therein.

If the face plate 152 is formed by CFRP, it may be manufactured to have the same linear expansion coefficient as the core 151, and thus it is not easily broken against temperature change, which is preferable. When the face plate 152 is manufactured by CFR P, it is possible to facilitate bonding to the core 151 and to provide magnetism by performing an electroplating operation such as nickel plating. Further, the mask body 10 shown in fig. 1A is a hybrid mask in which a metal support layer 12 having openings 12a formed so as not to block the opening patterns 11A of the resin film 11 is attached to the resin film 11 on which the opening patterns 11A are formed. However, the present invention is not limited to this structure, and is also applicable to a metal mask made of only the resin film 11 or a metal thin plate. In the case of the hybrid mask, the metal support layer 12 is bonded to the frame 15 together with the resin film 11.

As described above, the conventional vapor deposition mask has problems that the temperature of the vapor deposition mask 1 and the vapor deposition substrate 2 (see fig. 2) around the frame 15 is likely to increase, and the weight of the vapor deposition mask 1 is greatly increased and the size thereof is increased with the increase in size. That is, as described below, the vapor deposition material is emitted from the vapor deposition source 5 (see fig. 2) toward the vapor deposition mask 1 during vapor deposition. Therefore, the temperature of the vapor deposition source 5 is very high, and the portion of the frame 15 closest to the vapor deposition source 5 also increases in temperature by heat radiation. In the vapor deposition mask 1, the temperature of the portion of the metal supporting layer 12 naturally increases, and the heat is transmitted to the substrate 2 to be vapor deposited. However, as described above, the temperature of the portion of the frame 15 rises higher than the temperature of the metal support layer 12 located at the center, and the heat capacity is also large due to a certain weight. That is, since the conventional frame is formed of a solid bar material, the high temperature state is maintained for a long time because the heat capacity is large when the temperature rises. Therefore, when the vapor deposition of the vapor deposition substrate 2 is completed, and the vapor deposition substrate 2 is replaced, and vapor deposition is performed on another vapor deposition substrate 2, the temperature of the frame 15 is high from the beginning, and the temperature of the vapor deposition substrate 2 in the vicinity thereof is likely to increase from the beginning after mounting. Therefore, the thermal expansion of the peripheral portion of the deposition target substrate 2 is large, and the position of the deposition target substrate is likely to be displaced from the central portion.

In addition, when the size of the vapor deposition mask is increased, the weight of the frame 15 having the structure shown in fig. 1A becomes a problem, that is, as described above, the mask body 10 composed of the resin film 11 and the metal support layer 12 is joined to the frame 15, and the mask body 10 is attached to the frame 15 by applying tension from the viewpoint of stability of the opening shape, for example, the tension is about 10N for each strip-shaped resin film 11 shown in fig. 1, and the width and thickness of the frame 15 need to be about several tens mm, respectively, for example, when the vapor deposition mask 1 having the aforementioned size of G6H is formed by a bar material having a square of 50mm × mm, the size of G6H is the size of the substrate, and since the frame 15 is provided at the outer periphery thereof, the length of each side of the frame 15 is 50mm longer than the size of G6H, for example, since the frame 15 has a rectangular frame shape, it is possible to increase only the length of the two long sides of the frame 15 and to make the frame of the short side to be consistent with the size of the substrate, but in this case, the long frame needs to be set to be twice the frame width (about 100.

Thus, the total volume of the frame 15 is 2 × (1550mm +950mm) × 2000mm²＝10000cm³. Preferably, as described above, the material of the frame 15 is close to the linear expansion coefficient of the evaporated substrate 2 (see fig. 2). Since glass, polyimide having a linear expansion coefficient close to that of glass, or the like is used as the deposition target substrate 2, invar is generally used as the metal supporting layer 12 and the frame 15 of the deposition mask 1. The invar steel has a specific gravity of about 8 and a weight of about 80 kg. In order to achieve an increase in size compared to G6H, not only the sides of the frame 15 need to be longer, but also the width and thickness of the frame 15 need to be increased, and the weight thereof will be further increased. As a result, the robot cannot carry the object.

The present inventors have made extensive studies to solve the above-described problems, and have found that CFRP is suitable as a material for the frame 15 of the vapor deposition mask 1, which is a material having a small linear expansion coefficient, a small thermal conductivity, a high strength, and a light weight. The CFRP has the following physical properties, and has a small specific gravity, and can be significantly reduced in weight. Further, the sandwich structure 150 (see fig. 1B) is formed by attaching the panel 152 to at least a part of the periphery thereof, which has a gap therein, so that heat conduction can be suppressed while further reducing the weight.

CFRP is a composite material of carbon fibers (broadly, carbon fibers including various carbon fiber materials such as high-strength carbon fibers, high-rigidity carbon fibers, glass fibers, and silicon carbide (SiC) as reinforcing fibers in addition to ordinary carbon fibers in a narrow sense) and plastic (resin), and by bonding the composite material to plastic, it is possible to exhibit strong, lightweight, and fine material characteristics of the carbon fiber materials. By changing the type of such reinforcing fibers, the values of the linear expansion coefficient and the thermal conductivity can be adjusted in addition to the tensile strength, the tensile modulus, the bending strength, and the bending modulus. Among them, SiCFRP using silicon carbide as a reinforcing fiber has a linear expansion coefficient close to that of polyimide, and is therefore suitable for use as a mask frame.

CFRP has the following characteristics:

(a) the specific gravity of the steel is 1.5-1.7, is smaller than 2.698 of Al, and is far smaller than 8.05 of invar as a magnetic body, 7.87 of Fe and 8.9 of Ni. That is, the weight can be reduced by about 1/4-1/5 compared to a conventional frame using invar steel compared to the same solid material.

(b) The strength is very high. Namely, the strength is 700 to 3300MPa, which is greater than 500 of Al and approximately equal to 1000 of Fe.

(c) The rigidity is 55-550 GPa, which is not inferior to that of 80 of Al and 200 of Fe, and even can be higher than the rigidity of the Al and the Fe.

(d) Further, the linear expansion coefficient was 3 ppm/deg.C, and it was possible to set the linear expansion coefficient thereof to 0 by controlling the kind and direction of the fiber. In addition, the linear expansion coefficient of the carbon fiber is-0.4- +1.5 ppm/DEG C, the linear expansion coefficient of the resin is +50 ppm/DEG C, and the linear expansion coefficient of the invar steel is + 1.5- +4.9 ppm/DEG C.

(e) The thermal conductivity is 7-800W/(m.DEG C.), which varies greatly depending on the type and direction of the fiber, but many materials are an order of magnitude higher than 0.2W/(m.DEG C.) of the resin, and are also much higher than 13W/(m.DEG C.) of invar. The high thermal conductivity means that the temperature rising on the vapor deposition source 5 side of the frame 15 is easily conducted to the vapor deposition substrate 2 side, but the heat dissipation effect is better because a material having a good thermal conductivity such as stainless steel (thermal conductivity (16.7 to 20.9) W/(m · ° c) or aluminum (thermal conductivity: 236W/(m · ° c)) is used for the mask holder 19, and the mask holder 19 has a better thermal conductivity, and as a result, the effect of dissipating heat by the mask holder 19 is more remarkable than the effect of conducting heat to the vapor deposition substrate 2 side through the gap 151a, and therefore, the thermal capacity is reduced in addition to the weight reduction by the gap 151a, and the problem of heat accumulation is solved.

(f) Although non-magnetic, in the case of a hybrid mask, if the metal support layer 12 of the mask body 10 is made of a magnetic body such as invar, nickel, or the like, or the material of the high-fineness metal mask is made of a magnetic body such as invar or the like, it may be attracted by a magnet. Further, the panel 152 made of a magnetic material may be attached to the periphery of the frame 15 made of CFRP so as to be attracted by a magnet.

(g) Since the vapor deposition mask 1 has high corrosion resistance, weather resistance, acid resistance, and alkali resistance, it can withstand repeated cleaning of the vapor deposition mask 1.

(h) Having anisotropy and the mechanical strength differs depending on the direction, amount, position, and the like of the carbon fiber, the mechanical strength in a specific direction can be increased. That is, in general, as shown in fig. 6A, in an injection molded article, a molten resin flows in a mold, and the direction of the filler 172 is aligned in a direction in the resin 171, in which direction a high mechanical strength can be obtained. Therefore, the direction in which stress is particularly applied may be taken as the direction.

As described above, CFRP is formed by mixing carbon fibers in a broad sense into a resin as a base material (matrix). As described above, various materials can be used as the carbon fiber. For example, high strength carbon fiber (linear expansion coefficient: -0.2-0.4 ppm/DEG C) and high rigidity carbon fiber (linear expansion coefficient: -0.8)ppm/c), silicon carbide (coefficient of linear expansion: 2.6 ppm/c) and the like, and is close to the substrate to be deposited. In addition, the tensile strength of these CFRPs was also large, about 150kgf/mm². Although thermosetting resin or thermoplastic resin can be used as the resin, thermosetting polyimide resin is preferable as the frame 15 of the vapor deposition mask 1. This is because a polyimide film can be used for the resin film 11 of the mask body 10 and the vapor deposition substrate 2. Since the thermosetting polyimide is used, it cannot be bent, and if it exceeds the limit, it is brittle and broken. However, it is preferable because bending or the like is less likely to occur. This material cannot be directly welded, but welding can be performed by forming a metal film by, for example, electroless plating, electrolytic plating, sputtering, vacuum evaporation, or the like. Further, even if the material is different, since a mechanical coupling method using a polyimide adhesive or a bolt and a nut can be used, a metal plate or the like can be attached. The heat resistant temperature is limited by the base material, but in the case of polyimide, the heat resistant temperature can be as high as about 500 ℃. In the case of producing a sandwich structure by molding, at least one of the face plates 152 may be molded integrally with the core 151 at the same time.

If such a material is used, as described above, since the specific gravity is very small, the weight can be reduced to 1/4 or less of invar even in a solid state, however, even if the core 151 having the voids 151a and the thin-walled portions 151b such as a honeycomb structure is made to be a sandwich structure by the face sheet 152, sufficient mechanical strength can be obtained, and the weight can be further reduced to about 1/5. As a result, the total weight can be reduced to about 1/20 compared to a conventional solid material made of invar. In this case, since the core portion 151 cannot be directly welded as described above, welding can be performed by bonding with a polyimide-based adhesive or covering the surface thereof with a metal film. By forming the sandwich structure 150 in this manner, the weight is reduced. In order to form the core 151, a mold having such a structure may be formed, and a base material mixed with carbon fibers may be injected. In addition, the void 151a may be formed on the solid material by machining. As described later, the core 151 and the panel 152 are preferably attached under a vacuum atmosphere or an inert gas atmosphere.

By plating the entire core 151 with nickel, for example, before the face plate 152 is attached, gas leaching from the material of the core 151 itself can be prevented, and welding such as laser welding of the face plate 152 and the mask body 10 described later can be achieved. In addition, in the case where the core 151 is formed by mold molding, one of the face plates 152 may be formed in one piece. In addition, in the case of a wave structure as shown in fig. 3B, which will be described later, the upper and lower panels 162 may also be integrally formed with the wave plate 161B, and the panels 162 may be further attached at the sides thereof. Further, instead of forming a part of the panel 152, 162 integrally with the core 151, 161, the panel 152, 162 may be formed by CFRP and may be adhered to the core 151, 161 by a polyimide-based adhesive. Alternatively, the metal film may be formed by plating or the like on the surface of a plate-like body made of CFRP, thereby realizing welding or the like of the face plates 152 and 162 to the mask main body 10 and the core portions 151 and 161.

The CFRP material has a tensile strength of 150kgf/mm²The tensile modulus of elasticity was 15000 kgf/mm²The thickness of the invar steel is 59.7kgf/mm respectively²、12700kgf/mm²Therefore, most of the time, the strength is higher than that of the existing invar. As described above, the weight of the steel sheet is about 1/4, and the steel sheet can be reduced to about 1/20 by forming a sandwich structure. As a result, the vapor deposition mask can be used with a robot arm which is smaller than before.

(Structure of vapor deposition mask)

Specifically, as shown in a side view of fig. 1C seen from an arrow C of fig. 1A, the frame 15 is formed with a through-hole (void) 151A, and the through-hole 151A is formed in a hexagonal shape. In this case, the buckling stress is further increased by injection molding in the direction of the through-hole 151a to orient the filler of the carbon fiber. By forming such a hexagonal honeycomb structure, not only the axial stress of the through-holes 151a but also the stress against the opening surface and the vertical direction of the through-holes 151a is very strong. The reason for this is that, for example, as shown in the schematic view of the honeycomb structure in fig. 5, when the lateral stress P is applied to the through-hole 151a, the stress is uniformly distributed to the respective sides of the hexagonal shape. Therefore, the resistance to the transverse stress P is also very strong, and the strength per unit mass of the stress is 2 to 3 times that of a solid material. Conversely, the weight can be reduced to about 1/4 to 1/6 in order to maintain the same stress. Further, since the material is the same, the physical constants such as the linear expansion coefficient and the tensile strength do not change, and since the voids (through-holes 151a) are present, the volume of the thin portion 151b is reduced, and the heat capacity is also reduced. The pressure of the through-hole 151a is reduced or a rare gas such as argon is sealed when the panel 152 described later is attached, whereby the heat storage in the gap portion can be further reduced.

In this example, although the honeycomb structure in a narrow sense of a regular hexagon is described as an example, the shape of the void 151a is not necessarily limited to a regular hexagon, and stress from the side surface is somewhat weakened, but a deformed hexagon, a polygon other than a hexagon, or an extreme case may be a circle. In the case of a circular shape, by making a circular hole with a small radius contact in a region surrounded by four circles, similarly, the number of voids 151a is large, and the thin-meat portion 151b of thin meat can be formed. In this specification, a honeycomb structure in a broad sense including these structures is referred to as a honeycomb structure. In the present embodiment, not only the honeycomb structure, but also the wavy structure shown in fig. 3A to 3B, the direction of the applied stress is directed in the axial direction of the through-hole (gap) 161a, whereby the frame 15 having the same light weight and the large mechanical strength is formed.

In the structure shown in fig. 3A, the core 161 is shaped into a wavy wave plate 161 b. The corrugated plate 161b is formed by integrally forming a panel 162 on the outer side of the crest and trough, or by forming a sandwich structure 16 by subsequent adhesion. In this structure, although the resistance to the force from the left-right lateral direction of fig. 3A (x-axis direction in fig. 3A) is slightly weak, the resistance to the stress in the axial direction (y-axis direction in fig. 3A) is strong, and the resistance to the stress in the z-axis direction is also strong to some extent. In this case, as shown in fig. 3B, the wave plate 161B and the panel 162 are firmly adhered to each other, or a greater mechanical strength can be obtained by forming a meat storage part at the junction between the wave plate 161B and the panel 162 when molding. Therefore, it is preferable that the wavy crests and troughs 161b1 of the wavy plate 161b be flattened to some extent to form a joint portion by the adhesive 163, the meat storage portion, or the like. In the example shown in fig. 3A, although the panel 162 is provided only on the upper and lower surfaces, it is preferable to cover the panel 162 also around the side surface.

As described above, the core 151 of the sandwich structure 150 having the aforementioned honeycomb structure is formed integrally with the face plate 152 on one side by a mold. As shown in the plan view of fig. 6B, the thickness d of the thin-walled portion 151B is formed to be about 1mm, and as described above, the lower face plate 152 may be integrally formed with the core 151. By die forming, a larger core 151 is formed, after which cutting can be performed with the desired width t. The height h of the through-holes 151A (the height h of the core 151 of the honeycomb structure when the frame 15 having the structure shown in fig. 1A is formed (see fig. 1B)) is formed to be about 20 to 50 mm. The height h may be cut according to the height h after forming a large honeycomb structure by injection molding. The upper panel 152 of fig. 6C may be attached by, for example, a polyimide-based adhesive.

In this example, the cell size c shown in fig. 6B is formed to be about 5mm to 10 mm. A perspective view of this state is shown in fig. 6C. A column having a regular hexagon with a cross section having a length (width of frame) s (see fig. 1C) obtained by adding the width t of the core 151 of fig. 6B to twice the thickness of the panel 152 described later and the height h described above is formed. The width s and the height h are each formed to be about several tens of millimeters, and the length is set according to the size of the vapor deposition mask 1. However, this is one example thereof, and these dimensions may be arbitrarily set depending on which direction the through-hole is directed to the frame.

The thickness d of the thin-walled portion 151b used in the above example is also not limited thereto, and a thickness capable of bearing a necessary load may be selected. For example, the plate thickness d of the thin-walled portion 151b may be increased in order to receive a large load. Further, this structure may form the through-hole 151a on the plate-like body without molding by a mold. Thus, a sandwich structure 150 having voids of various structures can be formed.

The sandwich structure 150 having the honeycomb structure has the following features: the bearing capacity for the in-plane/out-plane shear load and the in-plane compression load is strong, and the out-plane rigidity is high (the buckling strength is high). By applying the stress in the direction of maximum strength, the advantages (light weight and high rigidity) of the honeycomb structure can be utilized. Further, when the thickness d shown in fig. 6B and the cell size c shown in fig. 6B are used, since the larger the value of d/c, the higher the rigidity is, when it is desired to increase the rigidity, it is possible to easily obtain the desired rigidity by increasing the plate thickness d of the thin-walled portion 151B and reducing the cell size c.

The core 151 thus formed can be used as a material having high rigidity, but as shown in fig. 1C, the rigidity can be further improved by forming the sandwich structure 150 by surrounding the periphery thereof with the panel 152. For example, the panel 152 uses invar steel with a thickness of about 3 mm. In fig. 1C, the panel 152 blocking the gap (through-hole) 151a is not shown to facilitate understanding of the internal structure. The face plate 152 may be adhered to each face of the hexagonal cylinder, but as described above, the face plate 152 facing the through-hole 151a may be integrally formed with the core 151, and the rigidity in all directions may be enhanced by molding only the core 151 and then bending around 4 sides with 1 or 2 sheets of the plate material to perform the adhesion. Even when one face plate 152 is integrally formed with the core 151, the face plate 152 made of a metal plate may be further bonded thereto. Sometimes convenient in the case of magnetic attraction. When used as the frame 15 of the vapor deposition mask 1, it is preferable not only in terms of rigidity but also in terms of suppressing intrusion of an organic material or the like into the void 151 a. That is, the organic material floats in the vacuum chamber during vapor deposition and easily enters the gap 151 a. After a certain degree of vapor deposition, it is necessary to remove the organic material adhering to the vapor deposition mask 1 and periodically clean the vapor deposition mask 1. During this cleaning, the cleaning liquid also enters the gap 151a, and may remain in the gap 151a even after the cleaning. Since the vapor deposition mask 1 is installed in a vacuum chamber and vapor deposition is performed, if a cleaning liquid remains in the gap after vacuum, it becomes a gas source and normal vapor deposition cannot be performed.

Therefore, the gap 151a is preferably sealed by the panel 152. Since the surface plate 152 is preferably attached for the same reason because the surface plate has irregularities not only on the opening surface of the gap (through hole) 151a but also on the side surface (side surface parallel to the through hole 152). The panel 152 may be attached by a polyimide adhesive or the like. In the upper and lower surfaces shown in fig. 6B, a portion at the face of the core 151 and a portion at which the panel 152 can be bonded can be firmly connected, but at the left and right faces of fig. 6B and the opening face of the void 151a, since the contact area of the core 151 and the panel 152 becomes small, a sufficient adhesive is required. However, as described above, the panel 152 is not attached to each side surface, and one metal plate is bent and attached, so that the resistance to stress is strong and the adhesion strength with the core 151 is strong. As a result, as described above, it is preferable that all six sides of the hexagonal prism be surrounded by the face plate 152.

The rod-shaped sandwich structure 150 thus formed is prepared in accordance with the length of the long-side vertical frame 15a and the short-side horizontal frame 15b of the vapor deposition mask 1, and the frame body of the frame 15 is manufactured by joining the end portions. The rod-like sandwich structure 150 is joined by a conventional bolt or the like, but in the present embodiment, sufficient fixation is required so that a large amount of gap twist or the like does not occur. Therefore, it is preferable that a splint or the like is attached to a corner of the rectangular frame shape, and the sandwich structure 150 is inserted and fastened by a bolt and a nut. The corner portions are sufficiently joined, and a phenomenon such as twisting is hardly generated.

As described above, the gap 151a is preferably blocked by the panel 152, but more preferably, when the gap 151a is blocked, the panel 152 is attached under reduced pressure, so that the inside of the gap 151a is set to negative pressure (reduced pressure). As described above, this is because the vapor deposition mask 1 is used in a vacuum vapor deposition apparatus, and therefore, when the inside of the gap 151a is sealed with one atmospheric pressure, there is a possibility that leakage of gas staying in the gap 151a occurs in the vacuum chamber, which lowers the degree of vacuum in the vacuum chamber. In addition, when the pressure is negative, the amount of heat stored in the space is also reduced, and the amount of heat conduction to the mask holder 19 of the frame 15 heated by the vapor deposition source 5 (see fig. 2) can be further promoted.

From the viewpoint of suppressing heat conduction to the deposition substrate 2 side, by enclosing a rare gas such as argon in the gap 151a, heat conduction to the deposition substrate 2 side can be further suppressed, thereby contributing to heat conduction to the mask holder 19 side. This is because the thermal conductivity of the rare gas is small. In order to reduce the pressure in the void 151a or to seal a rare gas therein, the core 151 and the panel 152 may be joined under a reduced pressure atmosphere and/or an inert gas atmosphere.

In the example shown in fig. 1A, in the portion of the vertical frame 15a of the frame 15 corresponding to the long side of the rectangular vapor deposition mask 1, the core 151 is formed such that a void (through hole) 151A faces outward from the center in the plane of the vapor deposition mask 1. Therefore, as shown in fig. 1B, a B-B sectional view of fig. 1A, the through-hole (void) 151A extends in the lateral direction, and as shown in a view seen from an arrow C of fig. 1A of fig. 1C (a view in which the panel 152 is removed), the planar shape of the void 151A is exhibited as it is.

The sandwich structure 150 having such voids 151a is particularly strong in load in the direction parallel to the axis of the voids 151 a. On the other hand, as described above, in order to reliably stabilize the opening 11a of the resin film 11, the vapor deposition mask 1 is joined to the frame 15 in a state in which tension is applied by stretching the mask main body 10 (see fig. 1B) composed of the resin film 11 and the metal support layer 12. Although there are various methods for attaching the mask body 10 to the frame 15, in the example shown in fig. 1A, only 5 mask bodies 10 in a strip shape are shown, but actually, for example, in the example of sequentially attaching 12 mask bodies, as shown in fig. 1A, the mask bodies are stretched along the lateral frames 15b on the short sides of the rectangular frame 15 and joined to the longitudinal frames 15a on the long sides by welding or the like. Therefore, in the direction in which the tension is applied, that is, in the direction in which the short-side horizontal frame 15b extends, the long-side vertical frame 15a is formed so that the gap 151A faces outward (leftward and rightward in fig. 1A) from the center of the vapor deposition mask 1. In the case where the metal support layer 12 is not present, it may be directly bonded to the resin film 11 by an adhesive or the like. In this case, a binder which does not generate gas at the time of vapor deposition is used. For example, as the adhesive, a completely curable adhesive, such as a thermosetting epoxy resin or a polyimide-based resin, is preferable.

When the strip-shaped mask body 10 is welded to the frame 15, the end portions of the mask body 10 are extended, and as shown in fig. 4, the end portions of the mask body 10 are joined to the outer surface of the frame 15 opposite to the center portion of the mask body 10, that is, the outer peripheral wall opposite to the inner surface of the frame 15, so that it is more securely resistant to stress caused by tension. At this time, welding is performed from the right side surface of fig. 4. In particular, without the metal support layer 12, the effect is remarkable when only the resin film 11 is stuck with an adhesive.

In the case where the vapor deposition mask 1 is disposed in a vertical direction (a vertical direction in the vertical relation shown in fig. 2) in the frame 15b on the short side of the frame 15, and is used as a vertical vapor deposition device, most of the weight of the vapor deposition mask 1 is received on the lower side when the vertical vapor deposition device is erected (not all the weight may be present because the vertical vapor deposition device is not vertically erected, but is disposed in an inclined manner), and the frame 15b on the short side is also formed so that the gap 151a faces in the outer direction in the plane from the center of the vapor deposition mask 1. At this time, since a force of pulling the vertical frames 15a on the two opposing long sides is applied, it is necessary to be able to receive a large load in the longitudinal direction of the horizontal frame 15b on the short side. In the above example, since the longitudinal direction of the lateral frame 15b of the short side is the lateral direction of the core 151, the strength against the load of the lateral frame 15b in the longitudinal direction may be weaker than the strength against the load in the direction perpendicular to the opening face of the void 151 a. However, as described above, in the case of the regular hexagonal honeycomb structure, even if a load is applied in the lateral direction, the force is uniformly distributed to the sides of the hexagon, and thus the load can be sufficiently received. In addition, the mask body 10 of the vapor deposition mask 1 is sometimes not strip-shaped, but a large mask having a square shape is attached by being stretched in four directions, and in this case, the direction of the core 151 is arranged so that the gap 151a is oriented in a direction perpendicular to the sides, as in the case of the longitudinal frame 15a having the long sides described above. Therefore, the honeycomb structure of the long-side vertical frame 15a and the honeycomb structure of the short-side horizontal frame 15b are oriented in different directions. In summary, the vapor deposition mask 1 has the following features: the orientation of the gap 151a in the sandwich structure differs between the longitudinal frame 15a on the long side and the lateral frame 15b on the short side. However, the orientation of the voids of each side of the vapor deposition mask 1 may be appropriately adjusted according to the arrangement of the vapor deposition mask 1.

As shown in the cross-sectional view of fig. 1B, the mask body 10 of the vapor deposition mask 1 includes a resin film 11 and a metal supporting layer 12, and the metal supporting layer 12 is made of a magnetic material. As the metal support layer 12, for example, Fe, Co, Ni, Mn, or an alloy of these metals can be used. Among them, invar (an alloy of Fe and Ni) is particularly preferably used because the difference in linear expansion coefficient from the deposition target substrate 2 is small and hardly expands by heat. The thickness of the metal support layer 12 is formed to be about 5 μm to 30 μm.

In fig. 1B, the openings 11a of the resin film 11 and the openings 12a of the metal supporting layer 12 are tapered toward the deposition target substrate 2 (see fig. 2). The reason is that when the vapor deposition material 51 (see fig. 2) is vapor-deposited, the vapor deposition material 51 does not scatter as a shadow. The mask body 10 is not limited to the hybrid type mask, and may be a metal mask alone or a mask including only a resin film.

In the case where the mask body 10 is a metal mask, an opening pattern is formed using, for example, an invar sheet having a thickness of about 30 μm. The opening pattern is formed into a tapered shape in which the vapor deposition substrate side is tapered, as in the case of the resin mask, by adjusting the conditions of etching processing. Such a mask body may be formed in a strip shape as shown in fig. 1A, and a plurality of mask bodies may be attached, or may be attached as one mask body. The metal mask may be attached to the frame by applying tension and welding. The metal mask is easily curled and therefore requires a larger tension than the resin mask, but since the frame of the present embodiment is very strong, the effect of the frame of the present embodiment using the metal mask is more remarkable than that of the mask using the resin film.

The vapor deposition mask 1 can be obtained by attaching the mask body 10 to the frame-shaped frame 15. The vapor deposition mask 1 has a structure in which the metal supporting layer 12 is attached to the resin film 11, but the metal supporting layer 12 may be omitted. In the case where the metal support layer 12 is not present, the resin film 11 needs to be further stabilized, and therefore needs to be fixed to a strong frame 15. As a result, although the frame 15 is easily heavy, the sandwich structure 150 having the gap 151a can prevent an increase in weight. When the metal support layer 12 is not provided, a magnetic body is used for the frame 15 of the vapor deposition mask 1, whereby the magnetic body can be attracted.

By forming the frame 15 of the vapor deposition mask 1 into the sandwich structure 150 having such a gap 151a, the weight is made very light, that is, by adopting the honeycomb structure having the structure shown in fig. 6D, although the weight of the vapor deposition mask 1 of G6H is reduced to about 1/20 compared with the solid state of the conventional invar, there is no problem in stress generated by attaching the mask body 10, as a result, even if the weight is about 3 to 4 times heavier than that, that is, the vapor deposition mask 1 having a size of G8 (about 2200mm × 2400mm) or more than G8 can be smoothly transported by a robot arm, and even if the transportation by the robot arm is possible, a space is required in the horizontal vapor deposition apparatus 1, and particularly in the manufacture of an organic E L display device, since about 6 to 10 vacuum chambers are arranged, the vapor deposition substrates 2 to be sequentially replaced for vapor deposition, a very large space is required.

In the vapor deposition mask according to the present embodiment, the frame 15 has a large number of voids 151 a. Therefore, the heat capacity is greatly reduced. As a result, heat accumulation is reduced, heat conduction to the new vapor deposition substrate 2 after replacement is suppressed, and temperature distribution between the vapor deposition mask 1 and the vapor deposition substrate 2 is less likely to occur. Thereby, a finer pattern of the organic layer can be formed.

According to the vapor deposition mask 1 of the present embodiment, the frame 15 is significantly reduced in weight, and therefore, the heat capacity is reduced. Therefore, it is reasonable that the temperature easily rises, but conversely becomes easily lowered. That is, even when the vapor deposition substrate 2 is replaced and the organic material is continuously deposited on a large number of vapor deposition substrates 2, a phenomenon in which heat is accumulated in the vapor deposition mask 1 and the next vapor deposition substrate 2 is heated immediately after being placed does not occur. As a result, a stable evaporation operation can be repeatedly performed.

(schematic configuration of vapor deposition apparatus)

As shown in fig. 2, a vapor deposition device using a vapor deposition mask 1 according to one embodiment of the present invention is provided in such a manner that a mask holder 19 and a substrate holder 29 can move up and down, so that the vapor deposition mask 1 and a substrate 2 to be vapor deposited are disposed close to each other in a vacuum chamber. The substrate holder 29 holds the peripheral edge portion of the deposition substrate 2 by a plurality of hook-shaped arms, and is connected to a driving device (not shown) so as to be movable up and down. In the case of replacing the vapor deposition substrate 2 or the like, the vapor deposition substrate 2 conveyed into the vacuum chamber by the robot arm is received by the hook arm, and the substrate holder 29 is lowered until the vapor deposition substrate 2 approaches the vapor deposition mask 1. An imaging device, not shown, is also provided for positioning. The touch panel 4 is supported by a support frame 41, and is connected via the support frame 41 to a driving device that lowers the touch panel 4 until it comes into contact with the evaporated substrate 2. By lowering the touch panel 4, the vapor deposition substrate 2 is flattened.

When the vapor deposition mask 1 and the vapor deposition substrate 2 of the first embodiment are aligned, the vapor deposition device captures alignment marks formed on the vapor deposition mask 1 and the vapor deposition substrate 2, respectively, and also provides a fine adjustment device for moving the vapor deposition substrate 2 relative to the vapor deposition mask 1. At the time of alignment, power supply to the electromagnet 3 is stopped so that the vapor deposition mask 1 is not unnecessarily attracted by the electromagnet 3. Thereafter, the touch panel 4 and the electromagnet 3 held by the same holder, not shown, are lowered to pass a current, thereby attracting the vapor deposition mask 1 toward the vapor deposition substrate 2.

In the present embodiment, since the frame 15 of the vapor deposition mask 1 is configured to sandwich the core 151 of the sandwich structure 150 having a gap between the face plates 152, the access operation can be performed lightly by a robot arm not shown.

The electromagnet 3 is constituted by a plurality of unit electromagnets each of whose core 31 is wound by a coil 32, and the plurality of unit electromagnets are fixed by a covering 33 made of resin or the like, in the example shown in fig. 2, the plurality of unit electromagnets are connected in series, and terminals 32a to 32e of the coil 32 of each unit electromagnet are formed, however, the structure of the electromagnet 3 is not limited to this example, and various structures may be adopted, the shape of the core 31 may be square or circular, for example, in the case where the size of the vapor deposition mask 1 is about G6(1500mm × 1800mm), as shown in fig. 2, the unit electromagnets having the core 31 with a cross section of about 50mm as shown in fig. 1 may be arranged in plurality side by side (in fig. 2, the horizontal direction is scaled down, the number of unit electromagnets is reduced), in the example shown in fig. 2, the coils 32 are connected in series, however, the coils 32 of the respective unit electromagnets may be connected in parallel, in series, and in addition, a plurality of units may be connected in series.

As shown in fig. 1B, the vapor deposition mask 1 includes a resin film 11, a metal support layer 12, and a frame (frame body) 15 formed around the resin film and, as shown in fig. 2, the frame 15 of the vapor deposition mask 1 is placed on a mask holder 19. By using a magnetic material for the metal support layer 12 and/or the frame 15, an attractive force acts between the cores 31 of the electromagnets 3, and the deposition substrate 2 is clamped and attracted.

The vapor deposition source 5 may be any of various vapor deposition sources such as a dot, a line, and a plane. For example, a linear vapor deposition source 5 (extending in a direction perpendicular to the paper surface of fig. 2) in which crucibles are arranged in a linear shape performs vapor deposition on the entire surface of the vapor deposition substrate 2 by scanning from the left end to the right end of the paper surface. Therefore, the openings 11a and 12a are formed in a tapered shape so that the vapor deposition material 51 is scattered in all directions and the vapor deposition material 51 that flies in an oblique direction reaches the vapor deposition substrate 2 without being blocked.

(vapor deposition method)

Next, a vapor deposition method according to a second embodiment of the present invention will be described. As shown in fig. 2, the vapor deposition method according to the second embodiment of the present invention includes a step of arranging the vapor deposition target substrate 2 to overlap the vapor deposition mask 1 shown in fig. 1B, for example, and a step of depositing the vapor deposition material on the vapor deposition substrate 2 by scattering the vapor deposition material from the vapor deposition source 5 provided at a distance from the vapor deposition mask 1. That is, the frame 15 of the vapor deposition mask 1 is formed by a sandwich structure 150 in which a core portion 151 having voids 151a and thin-walled portions 151b is covered with a face plate 152, as in a honeycomb structure, on the frame 15 of the vapor deposition mask 1.

Specifically, as described above, the vapor deposition substrate 2 is placed on the vapor deposition mask 1 in a superposed manner, and the vapor deposition substrate 2 and the vapor deposition mask 1 are aligned with each other by relatively moving the vapor deposition substrate 2 with respect to the vapor deposition mask 1 while observing alignment marks formed on the vapor deposition substrate 2 and the vapor deposition mask 1 by an imaging device, whereby the openings 11a of the vapor deposition mask 1 can be aligned with vapor deposition sites of the vapor deposition substrate 2 (for example, in the case of an organic E L display device described later, the pattern of the first electrode 22 of the support substrate 21), and after the alignment, the electromagnet 3 is operated, and as a result, a strong attractive force is generated between the electromagnet 3 and the vapor deposition mask 1, and the vapor deposition substrate 2 and the vapor deposition mask 1 are brought into close proximity to each other.

Then, as shown in fig. 2, the vapor deposition material 51 is deposited on the vapor deposition substrate 2 by scattering (vaporization or sublimation) the vapor deposition material 51 from the vapor deposition source 5 provided at a distance from the vapor deposition mask 1. Specifically, as described above, a line source formed by linearly arranging crucibles or the like is used, but the present invention is not limited thereto.

According to this vapor deposition method, the vapor deposition mask 1 is lightweight, and therefore, it is very easy to install the vapor deposition mask 1 in a vacuum chamber. Further, since the weight is reduced, the vapor deposition mask 1 can be more easily transported by a robot arm, and can be further enlarged. That is, mass production is possible, and cost reduction is possible. Further, since the heat conduction and hence the heat capacity are reduced by the air gap 151a of the frame 15, the difference in thermal expansion between the deposition target substrate 2 and the deposition mask 1 can be suppressed by accumulating the heat in the deposition mask 1. As a result, vapor deposition on a large-sized substrate to be vapor deposited becomes possible, and fine vapor deposition can be performed.

(method for manufacturing organic E L display device)

Next, a method of manufacturing an organic E L display device using the vapor deposition method of the above embodiment will be described, and since manufacturing methods other than the vapor deposition method can be performed by known methods, a method of stacking organic layers by the vapor deposition method of the present invention will be mainly described with reference to fig. 7A to 7B.

The method for manufacturing an organic E L display device according to the third embodiment of the present invention includes a step of forming a laminated film 25 of organic layers by the vapor deposition method when forming TFTs, a planarizing film, and a first electrode (for example, an anode) 22, which are not shown, on a supporting substrate 21, and aligning and overlapping the vapor deposition mask 1 with the first electrode 22 facing downward to deposit a vapor deposition material 51, and thus forming a second electrode 26 (see fig. 7B; cathode) on the laminated film 25.

For example, although not completely illustrated, the support substrate 21 such as a glass plate is formed with a driving element such as a TFT for each RGB sub-pixel of each pixel, and the first electrode 22 connected to the driving element is formed on a planarization film by a combination of a metal film such as Ag or APC and an ITO film. As shown in FIGS. 7A to 7B, SiO for the local molecular pixels is formed between the sub-pixels₂Or an insulating bank 23 made of acrylic resin, polyimide resin, or the like. The vapor deposition mask 1 is fixed to the insulating bank 23 of the support substrate 21 in alignment. As shown in fig. 2, the fixing is performed by using, for example, an electromagnet 3 provided on the surface opposite to the deposition surface of the support substrate 21 (deposition target substrate 2) via the touch panel 4. As described above, since the magnetic body is used for the metal support layer 12 of the vapor deposition mask 1 (see fig. 1B), when a magnetic field is applied by the electromagnet 3, the metal support layer 12 of the vapor deposition mask 1 is magnetized, thereby generating an attractive force with the core 31. Even in the case where the electromagnet 3 does not have the core 31, it is attracted by a magnetic field generated by a current flowing through the coil 32.

In this state, as shown in fig. 7A, the vapor deposition material 51 is scattered from the vapor deposition source 5 (crucible) in the vacuum chamber, and the vapor deposition material 51 is deposited only on the portion of the support substrate 21 where the opening 11a of the vapor deposition mask 1 is exposed, thereby forming the laminated film 25 of the organic layer on the first electrode 22 of the desired sub-pixel. The vapor deposition step may be sequentially transferred to different vacuum chambers of the support substrate 21 to perform vapor deposition on each sub-pixel. An evaporation mask 1 that deposits the same material on a plurality of sub-pixels at the same time may be used. In the case of replacing the vapor deposition mask 1, a power supply circuit, not shown, is turned off to cancel the magnetic field generated by the electromagnet 3 (see fig. 2), not shown in fig. 7A, on the metal support layer 12 (see fig. 1B) of the vapor deposition mask 1.

Although the organic layer laminated film 25 is simply shown as 1 layer in fig. 7A to 7B, the organic layer laminated film 25 may be formed of a multilayer laminated film 25 made of different materials. For example, a hole injection layer made of a material having a high ionization energy matching property and improved hole injection properties may be provided as a layer in contact with the anode 22. On the hole injection layer, a hole transport layer is formed, for example, from an amine-based material, and the hole transport layer can improve the stable transport of holes and confine electrons to the light-emitting layer (energy barrier). Further, for example, red or green organic fluorescent material is doped in Alq with respect to red or green₃To form thereon a light emitting layer selected according to the light emitting wavelength. In addition, DSA-based organic materials are used as blue-based materials. On the light-emitting layer, passing Alq₃And the like, and can stably transport electrons while improving the electron injection property, and the like, the stacked film 25 of the organic layer is formed by stacking these layers by about several tens of nm, respectively, and an electron injection layer improving the electron injection property such as L iF, L iq, and the like is also provided between the organic layer and the metal electrode.

In the laminated film 25 of organic layers, organic layers of materials corresponding to respective colors of RGB are stacked on the light-emitting layer. In addition, if the light emitting property is important, it is preferable to separately deposit a hole transport layer, an electron transport layer, and the like, as appropriate for the material of the light emitting layer. However, in view of material cost, the same materials as those for 2 colors or 3 colors of RGB may be used for lamination. When a common material is laminated in sub-pixels of 2 or more colors, the vapor deposition mask 1 having the openings 11a is formed on the common sub-pixels. When the vapor deposition layers of the respective sub-pixels are different, for example, the respective organic layers may be successively vapor deposited in R sub-pixels using one vapor deposition mask 1. In the case of depositing a common organic layer by RGB, the organic layer of each sub-pixel is vapor-deposited on the lower side of the common layer, and the vapor deposition of the organic layers of all the pixels is performed at once using the vapor deposition mask 1 having the openings 11a formed in RGB in the common organic layer. In mass production, several vacuum chambers of vapor deposition apparatuses may be arranged, different vapor deposition masks 1 may be mounted, and the support substrate 21 (vapor deposition target substrate 2) may be moved in each vapor deposition apparatus to perform vapor deposition continuously.

Each time the formation of the laminated film 25 including the respective organic layers such as the electron injection layer of L iF layer and the like is finished, as described above, the electromagnet 3 is turned off, the electromagnet 3 is separated from the vapor deposition mask 1, and thereafter, the second electrode (e.g., cathode) 26 is formed over the entire surface thereof, the example shown In FIG. 7B adopts a manner that light is emitted from the opposite surface of the supporting substrate 21 In the drawing In a top emission type, and therefore the second electrode 26 is formed of a light-transmitting material such as a thin Mg-Ag eutectic film₃O₄Etc. as the second electrode 26, a metal having a small work function, for example, Mg, K, L i, Al, etc. may be used, and for example, Si is formed on the surface of the second electrode 26₃N₄Etc. to form the protective film 27. The entire structure is sealed with a sealing layer made of glass, a moisture-resistant resin film, or the like, not shown, and the laminated film 25 formed as an organic layer does not absorb moisture. The organic layer may be made as common as possible, and a color filter may be provided on the surface thereof.

(conclusion)

(1) A vapor deposition mask according to a first embodiment of the present invention includes a mask main body in which an opening pattern is formed, and a frame that is joined to at least a part of an edge portion of the mask main body to hold the mask main body in a fixed state, and the frame is formed of carbon fiber reinforced plastic.

As a result, the vapor deposition mask can be easily transported by a robot arm, and the upper limit of the size of the vapor deposition substrate used in the production line of the organic E L display device is about G6, whereas the vapor deposition mask according to an embodiment of the present invention can be significantly increased in size about G8 or more.

(2) The carbon fiber-reinforced plastic is a silicon carbide fiber-reinforced plastic having silicon carbide as a reinforcing fiber, but is preferably a silicon carbide fiber-reinforced plastic having a linear expansion coefficient close to that of the substrate to be vapor-deposited and a high rigidity.

(3) The sandwich structure is formed by attaching face plates made of carbon fiber reinforced plastic or metal plate to the opposing surfaces of at least a part of the columnar core portion including the void, thereby achieving further weight reduction. Further, since the gap is provided, the heat capacity is also reduced, and therefore, the accumulation of heat can be eliminated.

(4) Since the voids of the core are formed into a honeycomb structure in a broad sense, a sustainable rigidity can be obtained even if a lateral load is applied to the core in which the voids are formed.

(5) The vapor deposition mask according to any one of claims 1 to 4, which is a hybrid mask formed by bonding a resin film having the opening pattern formed thereon and a metal support layer having openings that do not block the opening pattern of the resin film to each other.

(6) In the case where the mask main body is a metal mask made of a thin metal plate on which the opening pattern is formed, a larger tension is required than in the case of a hybrid mask, and therefore, the strength of the frame can be improved.

(7) The frame has a rectangular frame shape, and the gap is formed from the inside surrounded by the frame toward the outside of the frame on the side of the frame to which the resin film is bonded.

(8) Preferably, the joining of the peripheral edge portion of the mask main body to the frame is performed by bending a part of the peripheral edge portion of the mask main body to join it to an outer peripheral side wall opposite to an inner side of the frame. By doing so, sufficient rigidity is easily obtained also with respect to the tension of the mask main body.

(9) The panel formed by the magnetic metal plate is adhered to the whole peripheral wall of the frame which is internally provided with the gap, so that the rigidity of resisting stress is enhanced, and simultaneously, the evaporation material such as organic material and the like can be prevented from entering the gap or cleaning liquid in cleaning is prevented from remaining in the gap. Further, the magnetic metal plate is more easily attracted to the magnet.

(10) Since the gap surrounded by the panel is depressurized, the gas that has entered the gap does not flow out even when used in a vacuum chamber, and therefore, it is preferable.

(11) Preferably, the inside of the space surrounded by the panel is filled with an inert gas, whereby heat accumulation is suppressed, and it is desirable.

(12) A vapor deposition method according to a second embodiment of the present invention includes a step of disposing a vapor deposition substrate so as to overlap the vapor deposition mask described in any one of (1) to (11) above, and a step of depositing the vapor deposition material on the vapor deposition substrate by scattering of the vapor deposition material from a vapor deposition source disposed at a distance from the vapor deposition mask.

According to the vapor deposition method of the second embodiment of the present invention, since the vapor deposition mask is made very light, the operation by the robot arm is facilitated, and the substrate can be formed in a larger size.

(13) The frame of the vapor deposition mask has a rectangular frame shape, and the vapor deposition substrate and the vapor deposition mask are arranged such that the side of the frame, which is formed by the gap extending from the inside surrounded by the frame to the outside of the frame, is positioned in the vertical direction, whereby sufficient rigidity against the self-weight of the vapor deposition mask can be obtained.

(14) The method for manufacturing an organic E L display device according to the third embodiment of the present invention includes a step of forming at least a TFT and a first electrode on a supporting substrate, depositing an organic material on the supporting substrate by using the deposition method described in (10) or (11) above to form a laminated film of organic layers, and then forming a second electrode on the laminated film.

According to the method of manufacturing the organic E L display device of the third embodiment of the present invention, the vapor deposition mask can be easily attached to the display device of the organic E L, and the uneven thermal expansion of the vapor deposition mask and the vapor deposition substrate can be suppressed, so that the misalignment between the vapor deposition substrate and the vapor deposition mask can be suppressed, and a display panel with a high-definition pattern can be obtained.

Description of the symbols

1 vapor deposition mask

2 substrate to be vapor-deposited

3 electromagnet

5 vapor deposition Source

10 mask body

11 resin film

11a opening

12 metal support layer

12a opening

15 frame

15a longitudinal frame

15b horizontal frame

150 sandwich structure

151 core part

151a space (through hole)

151b thin meat part

152 panel

19 mask holder

21 support substrate

22 first electrode

23 insulating dike

25 laminated film

26 second electrode

29 substrate holder