JP6906652B2 - Vapor deposition mask - Google Patents

Description

The present invention relates to a vapor deposition mask.

In recent years, an organic EL display device using an organic EL (Electro-luminescent) element has been put into practical use, and a vapor deposition method may be adopted when forming an organic layer or a cathode electrode of the organic EL element. In order to form the organic layer and the cathode electrode into a desired shape, a shadow mask formed by arranging a large number of fine slits in parallel is used. The development of the shadow mask is also in progress as the display device becomes higher in definition and higher in image quality. Shadow masks are also called vapor deposition masks and metal masks.

For example, Patent Document 1 describes a vapor deposition mask formed by laminating a metal mask provided with a slit and a resin mask provided with a pattern formed by vapor deposition at a position overlapping the slit by photolithography. Discloses the point of improving the processing accuracy of the vapor deposition mask.

In Patent Document 2, in a metal mask for organic EL that forms an organic EL layer on a substrate, a resin protrusion is provided on the outer periphery of a display portion on the surface side of the metal mask for organic EL that faces the substrate during vapor deposition. Discloses the point of preventing contact between the metal mask and the substrate and preventing damage to the substrate surface due to foreign matter or scratches.

Further, Patent Document 3 is a vapor deposition method in which a thin-film deposition mask is brought into close contact with the surface of a substrate and a pattern is formed by depositing a vapor-deposited material on the surface of the substrate through an opening of the vapor-film deposition mask from a vapor-deposit source. It discloses that the surface facing the surface is roughened by sandblasting to prevent peeling of the vapor-deposited material.

Japanese Unexamined Patent Publication No. 2013-241667 JP-A-2007-95411 Japanese Unexamined Patent Publication No. 2003-253434

As in Patent Documents 1 and 2, the thin-film deposition mask whose surface is made of resin has a smoother surface than the thin-film deposition mask whose surface is made of metal. Therefore, a film deposited on the surface of the thin-film deposition mask. May come off. When the film deposited on the surface of the vapor deposition mask is peeled off, the peeled film contaminates the vapor deposition source, and impurities are mixed in the film formed by the contaminated vapor deposition source.

Further, as in Patent Document 3, when the target of the roughening treatment is a vapor deposition mask whose surface is formed of a resin, the resin itself may be peeled off when the surface is roughened by the sandblasting treatment.

The present invention has been made in view of the above problems, and an object of the present invention is a shadow mask used for patterning in a film forming process in which a resin is provided on the surface, and the resin is used during the roughening treatment. It is an object of the present invention to provide a shadow mask that does not peel off and the film-forming material deposited on the resin does not easily peel off, and a display device manufactured by using the shadow mask.

One aspect of the present invention is a vapor deposition mask having a metal layer having a first opening and a first resin layer provided on the first surface side of the metal layer, wherein the vapor deposition mask is the metal. It has a first region in which the layer and the first resin layer are laminated, and a second region in which the first resin layer and the metal layer are not laminated, and the first resin layer is the second region. It has a second opening surrounded by, and the second opening has a tapered shape on its side wall.

It is a figure which shows schematicly the shadow mask which concerns on embodiment of this invention. It is an enlarged view of a part of a mask foil. FIG. 2 is a cross-sectional view showing a cross section III-III in FIG. 2 and a bird's-eye view in the vicinity of the cross section III-III. It is a figure for demonstrating an example in which distribution occurs in the thickness of the formed film. It is a figure which shows the cross section of the mask foil in another Example. It is a figure for demonstrating the manufacturing process of a mask foil. It is a figure for demonstrating the manufacturing process of a mask foil. It is a figure for demonstrating the manufacturing process of a mask foil.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual embodiment in order to clarify the explanation, but this is merely an example and the interpretation of the present invention is limited. It's not something to do. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals and detailed description thereof may be omitted as appropriate.

FIG. 1 is a diagram showing an outline of a shadow mask 100 according to an embodiment of the present invention. FIG. 1A shows a view of the shadow mask 100 from the side exposed to the film forming material, and FIG. 1B shows a view of the shadow mask 100 seen from the side facing the film forming object. As shown in the figure, the shadow mask 100 is formed by including a metal frame 102 and a plurality of strip-shaped mask foils 104 welded to the frame 102 by the welded portion 106.

The mask foil 104 has an opening 200 (see FIG. 2) according to the film formation pattern. Specifically, for example, when the film-forming object is a plurality of display panels formed on one glass substrate, the mask foil 104 is formed at each of the positions 108 corresponding to the plurality of display panels. It has an opening 200 according to the pattern.

Further, the shadow mask 100 is used for patterning in a film forming process by depositing a film forming material. Specifically, the shadow mask 100 is used in a state where the film-forming object is arranged on the side where the mask foil 104 is welded and the vapor deposition source or the like is arranged on the opposite side when the film-forming material is deposited. NS.

The welded mask foil 104 can be peeled off from the frame or 102. Therefore, according to the configuration of the shadow mask 100 shown in FIG. 1, even when the shape of the film forming pattern is changed, only the mask foil 104 needs to be replaced, and the frame 102 can be diverted. The cost of the shadow mask 100 can be reduced. Further, the configuration of the shadow mask 100 shown in FIG. 1 is an example, and may be a configuration without a frame 102.

FIG. 2 is an enlarged view of a part of the area corresponding to one display panel among the positions 108 corresponding to the plurality of display panels in the mask foil 104. As shown in FIG. 2, the mask foil 104 has an opening 200 corresponding to the pattern to be produced. Note that FIG. 2 illustrates a pattern in which a rectangular opening 200 is provided corresponding to each sub-pixel of the display panel, but the film formation pattern is not limited to this.

Further, the opening 200 of the mask foil 104 in FIG. 2 will be described in detail. 3A and 3B are a diagram showing a cross section III-III in FIG. 2 (FIG. 3A) and a diagram showing a bird's-eye view of the vicinity of the cross section III-III (FIG. 3B). As shown in FIGS. 3A and 3B, the mask foil 104 is formed including a first resin film 300, a metal portion 302, and a second resin film 304.

The first resin film 300 is provided on the side facing the film-forming object. Specifically, for example, the first resin film 300 is provided on the display panel side, which is the object of film formation, so as to have an inclined portion in the vicinity of the opening 200. The first resin film 300 is preferably formed of, for example, a resin such as polyimide, epoxy, or acrylic, but may be an inorganic material such as silicon oxide.

The metal portion 302 is provided above the first resin film 300, and a slit is formed. Specifically, for example, the metal portion 302 is formed with a slit larger than the opening 200 at a position overlapping the opening 200. Further, the metal portion 302 is formed so that the surface on which the slit is formed has an inclination, and is provided above the first resin film 300 so as to form a step together with the first resin film 300. The metal portion 302 is formed of, for example, an Invar material.

The second resin film 304 is provided on the side exposed to the film-forming material so as to cover at least a part above the metal portion 302. Specifically, for example, as shown in FIG. 3, it is provided on the side where the vapor deposition source, the target of the sputtering apparatus, or the like is arranged so as to cover all the first resin film 300 and the metal portion 302. Like the first resin film 300, the second resin film 304 is preferably formed of a resin such as polyimide, epoxy, or acrylic, but may be an inorganic material such as silicon oxide.

Further, the surface of the second resin film 304 is roughened. Specifically, for example, the second resin film 304 is roughened so as to have irregularities in a region formed so as to cover the top and side surfaces of the metal portion 302. Here, since the thickness of the mask foil 104 is about 0.02 to 0.2 mm, it is desirable that the height difference between the concave portion and the convex portion on the surface of the second resin film 304 is sufficiently smaller than 0.02 mm. In FIG. 3, of the second resin film 304, only the region provided so as to cover the top and side surfaces of the metal portion 302 is roughened, but the entire second resin film 304 is roughened. It may be roughened. The roughening treatment method will be described later.

By roughening the surface of the second resin film 304, it is possible to reduce the possibility that the film-forming material deposited on the mask foil 104 will peel off. That is, the film-forming material deposited in the recess formed on the surface of the second resin film 304 is more difficult to peel off than the film-forming material deposited on a flat resin film or the like, so that the deposited film-deposited material is peeled off. However, it is possible to prevent the vapor deposition source and the inside of the sputtering apparatus arranged on the second resin film 304 side from being contaminated.

Further, the second resin film 304 has an opening 200 corresponding to a pattern formed at a position overlapping the slit. Specifically, an opening 200 corresponding to a pattern to be produced with respect to the display panel is provided at a position overlapping the slit of the metal portion 302. The shape of the opening 200 provided in the second resin film 304 determines the shape of the film to be formed on the film formation target. For example, it has a rectangular opening 200 as shown in FIGS. 2 and 3 (a) and 3 (b). The film formed by using the mask foil 104 has the same shape as the opening 200 formed in the second resin film 304.

It is desirable that the second resin film 304 is formed thinner than the first resin film 300. Specifically, for example, as shown in FIG. 3, it is desirable that the second resin film 304 is formed to have a thickness of about half that of the first resin film 300. By forming the second resin film 304 thinner than the first resin film 300, the mask foil 104 is formed in a region where the second resin film 304 is formed on the upper portion of the metal portion 302, the first resin film 300. A region on which the second resin film 304 is formed and a region on which only the second resin film 304 is formed are provided, and regions having three different heights are formed in a stepped manner.

By forming the mask foil 104 in a stepped shape, the height of the film formed in the opening 200 can be made uniform. Here, for example, the film pressure distribution in the case where the film formation is performed using the mask foil 104 formed only by the metal portion 302 having the slit will be described.

FIG. 4A is a diagram showing the direction in which the molecules of the film to be deposited are incident on the film-forming object. Here, the arrow in FIG. 4 indicates the direction 400 in which the molecule incident on the film-forming object is incident on the film-forming object. FIG. 4B is a diagram showing the thickness of the film formed in one opening 200 in a plan view. Further, FIG. 4C is a diagram showing the distribution of the film thickness in the IV-IV cross section of FIG. 4B, in which the horizontal axis represents the position and the vertical axis represents the thickness.

As shown in FIG. 4, when the film is formed using the mask foil 104 formed only by the metal portion 302 having the slit, the film thickness of the formed film is distributed. Specifically, as shown in FIG. 4A, the film deposited on the central portion 404 of the slit is formed to include molecules that are vertically incident on the film-forming object and molecules that are incident on an oblique direction. NS.

On the other hand, at the end portion 402 of the slit, some of the molecules incident from the oblique direction do not reach the film formation target because the metal portion 302 acts as a barrier. Therefore, as shown in FIGS. 4B and 4C, the film thickness is distributed so that the film deposited on the end portion 402 of the slit is thinner than the film deposited on the central portion 404 of the slit. Occurs.

However, as in the above embodiment, the second resin film 304 in the vicinity of the opening 200 is formed thinly, and the mask foil 104 is formed in a stepped shape, so that the second resin film 304 is incident at the end of the opening 200 from an oblique direction. It is possible to prevent the molecules from being blocked and to form a film having a uniform height.

In the above description, the embodiment in which the mask foil 104 is formed in a staircase pattern so as to have three types of height regions has been described, but the mask foil 104 has two types of height regions. May be formed in. That is, as shown in FIG. 5, the first resin film 300 has an opening 200 corresponding to the pattern formed at a position overlapping the slit, and the second resin film 304 has the metal portion 302 and the first resin film 304. It may be formed so as to cover a part of the resin film 300. Even in this configuration, the mask foil 104 is formed in a staircase pattern so as to have regions of two heights, so that the film is compared with the case where the mask foil 104 is formed only by the metal portion 302. The thickness distribution can be reduced.

Subsequently, the manufacturing process of the mask foil 104 in the present invention will be described. 6 to 8 are views showing a method of manufacturing the mask foil 104 used for patterning in the film forming process by depositing the film forming material in the embodiment of the present invention.

First, as shown in FIG. 6A, a first resin film 300 is formed on the base material 600 over the entire surface of the base material 600. Further, a metal portion 302 provided with a slit is bonded onto the first resin film 300. Since the method of manufacturing the metal portion 302 provided with the slit is the same as that of the prior art, the description thereof is omitted here.

Next, as shown in FIG. 6B, the first resin film 300 formed in a part of the region provided with the slit is removed. Specifically, for example, the first resin film 300 is removed by irradiating the entire light-shielding mask with the laser light 602 through a light-shielding mask that transmits the laser light 602 only in the region where the first resin film 300 is to be removed. Only the region is irradiated with the laser beam 602. The laser beam 602 removes the first resin film 300 formed in a part of the region provided with the slit.

Subsequently, as shown in FIG. 6C, the second resin film 304 is formed so as to cover the metal portion 302, the first resin film 300, and the base material 600. Further, as shown in FIG. 7A, the surface of the second resin film 304 is roughened. Specifically, for example, by irradiating the entire light-shielding mask with the laser light 602 through a light-shielding mask that transmits the laser light 602 only in the area to be roughened, the laser light 602 is applied only to the area to be roughened. Irradiate.

Here, as the laser beam 602 used in the roughening treatment, the laser beam 602 having a smaller energy than the laser beam 602 used in the step of removing the first resin film 300 is used. That is, the second resin film 304 provided in the region to be roughened is irradiated with the laser beam 602 having an energy that does not remove the second resin film 304. By irradiating the laser beam 602, the second resin film 304 provided in the region irradiated with the laser beam 602 is roughened as shown in FIG. 7 (b).

Subsequently, as shown in FIG. 7C, an opening 200 corresponding to the pattern to be vapor-deposited is formed in the second resin film 304. Specifically, for example, by irradiating the entire shading mask with the laser beam 602 through a shading mask that transmits the laser beam 602 only in the region forming the opening 200, the laser beam is emitted only in the region forming the opening 200. Irradiate 602. Here, the laser beam 602 used in the step of forming an opening in the second resin film 304 is used in the roughening treatment in the same manner as the laser beam 602 used in the step of removing the first resin film 300. A laser beam 602 having a higher energy than the laser beam 602 used in the above is used. The step of roughening the second resin film 304 and the step of forming the opening 200 in the second resin film 304 are in no particular order, and either step may be performed first.

As shown in FIG. 8A, the laser beam 602 removes the second resin film 304 formed in the region forming the opening 200. Finally, as shown in FIG. 8B, the base material 600 is removed to complete the mask foil 104.

As described above, in the step of removing the first resin film 300, the step of roughening the second resin film 304, and the step of forming the opening 200 in the second resin film 304, all of the lasers are used. By using the light 602, each step can be performed using a common laser beam 602 emitting device. However, the method of roughening the second resin film is not limited to this. Specifically, for example, in the step shown in FIG. 7A, the second resin film 304 is formed by performing an ashing treatment instead of irradiating the second resin film 304 with the laser beam 602. It may be roughened.

Further, the step of roughening the second resin film 304 and the step of forming an opening in the second resin film 304 may be performed in the same step. Specifically, for example, in the region where the opening 200 is formed in the second resin film 304, the laser beam 602 is transmitted, and in the region where the second resin film 304 is roughened, the laser beam 602 is half. The step may be performed by using a light-shielding mask that transmits light and does not transmit the laser beam 602 in other regions. When the display panel to be filmed is irradiated with the laser beam 602 through the light-shielding mask, it has high energy to remove the second resin film 304 in the region where the opening 200 is formed in the second resin film 304. The laser beam 602 is irradiated. Further, in the region where the second resin film 304 is roughened, the laser beam 602, which is lower than the removal of the second resin film 304 and has sufficient energy for roughening, is irradiated. Further, since the laser beam 602 is not irradiated to the other region, the step of roughening the second resin film 304 and the step of forming an opening in the second resin film 304 are performed in the same step. Can be done.

Subsequently, a method of manufacturing a display device using the shadow mask 100 manufactured by the above method will be described. The manufacturing method of this display device is a manufacturing method of a display device including a display panel, in which a shadow mask 100 is obtained by the above method and the shadow mask 100 is used to form a mask foil 104 in the display panel. A step of forming a film having a pattern corresponding to the opening 200 is included.

Specifically, first, in a film forming apparatus such as a vapor deposition apparatus, the shadow mask 100 is fixed so that the surface on which the first resin film 300 is provided faces the display panel. Next, the molecules of the film-forming material are discharged from the vapor deposition source arranged on the side where the second resin film 304 is provided toward the display panel on which the shadow mask 100 is fixed. The released molecules are deposited on the surface of the second resin film 304 of the mask foil 104 and the surface of the display panel exposed from the opening 200 provided in the second resin film 304.

Then, when the fixed shadow mask 100 is removed from the display panel, a film having a pattern corresponding to the opening 200 formed in the mask foil 104 is formed on the display panel. The formed film includes, for example, as shown in FIG. 2, a light emitting element film made of a light emitting material corresponding to each sub-pixel of the display panel, and an electrode for passing an electric current through the light emitting element film. The manufacturing method of the display device includes steps other than the step of forming a film having a pattern corresponding to the opening 200, but the description thereof will be omitted here. Further, the method of depositing the molecules of the film-forming material is not limited to the thin-film deposition method, and may be a method such as sputtering.

According to the above manufacturing method, the film-forming material is deposited not only on the surface of the display panel but also on the surface of the second resin film 304 of the mask foil 104. However, according to the present invention, since the surface of the second resin film 304 is roughened, the film-forming material deposited on the surface of the second resin film 304 is compared with the case where the surface is not roughened. Is hard to peel off. Therefore, it is possible to reduce the possibility that the vapor deposition source is contaminated by the peeled film-forming material and impurities are mixed in the display panel.

Within the scope of the idea of the present invention, those skilled in the art can come up with various modified examples and modified examples, and it is understood that these modified examples and modified examples also belong to the scope of the present invention. For example, those skilled in the art appropriately adding, deleting, or changing the design of each of the above-described embodiments, or adding, omitting, or changing the conditions of the process are also gist of the present invention. Is included in the scope of the present invention as long as the above is provided.

100 shadow mask, 102 frame, 104 mask foil, 106 weld, 108 position corresponding to display panel, 200 opening, 300 first resin film, 302 metal part, 304 second resin film, 400 molecules are incident. Direction, 402 slit end, 404 slit center, 600 substrate, 602 laser beam.

Claims (2)

A metal layer having a first opening and
A thin-film mask having a first resin layer provided on the first surface side of the metal layer.
The vapor deposition mask has a first region in which the metal layer and the first resin layer are laminated, and a second region in which the first resin layer and the metal layer are not laminated.
The first resin layer has a second opening surrounded by the second region.
The first resin layer has a first surface facing the first surface of the metal layer and a second surface opposite to the first surface.
The width of the second opening on the first surface side is larger than the width on the second surface side.
The metal layer has a first surface and a second surface opposite to the first surface.
The width of the first opening on the first surface side is smaller than the width on the second surface side.
It has the second surface and side surface of the metal layer and the second resin layer covering the first surface and side surface of the first resin layer.
Thin-film mask. The second resin layer has a first surface facing the second surface of the metal layer, and a second surface opposite to the first surface,
The vapor deposition mask according to claim 1 , wherein the second surface of the second resin layer is roughened.

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