Display device

Abstract

In a TFT layer (20), a first metal film and a flattening film 19d are layered in this order. In a sealing film (45), a silicon nitride-based first inorganic sealing film (41) and a silicon oxynitride-based second inorganic sealing film (42) are layered in this order. In a frame region (F), a plurality of lead-out wires (18j) formed from the first metal film are provided so as to be each drawn out from the display region side to the terminal part side. A peripheral end (41e) of the first inorganic sealing film (41) is provided further to the outer side than a peripheral end (42e) of the second inorganic sealing film (42), at least on the terminal part side.

Description

display device

[0001] The present invention relates to a display device.

[0002] In recent years, self-luminous organic electroluminescence (EL) display devices using organic electroluminescence (EL) elements have been attracting attention as a display device that can replace liquid crystal display devices. These organic EL display devices include, for example, a base substrate such as a resin substrate, a thin film transistor (TFT) layer provided on the base substrate, an organic EL element layer provided on the TFT layer, and a sealing film provided on the organic EL element layer. Here, the sealing film includes, for example, a first inorganic sealing film provided to cover the organic EL element layer, an organic sealing film provided on the first inorganic sealing film, and a second inorganic sealing film provided on the first inorganic sealing film to cover the organic sealing film.

[0003] For example, Patent Document 1 discloses a display device having a sealing member (corresponding to the above-mentioned sealing film) including a lower sealing layer, an organic layer, and an upper sealing layer, in which the lower sealing layer is formed by sequentially stacking a first inorganic layer containing a nitride, a first intermediate inorganic layer containing a nitride and an oxynitride, and a second inorganic layer containing an oxynitride.

[0004] U.S. Pat. No. 1,065,8616 (FIG. 6)

[0005] An organic EL display device includes a display area for displaying an image, a frame area surrounding the display area, terminals provided at edges of the frame area, and a plurality of lead-out wirings provided in the frame area so as to be led from the display area side to the terminals side. Here, when the first inorganic sealing film is formed of, for example, a laminated film in which a silicon nitride film and a silicon oxynitride film are sequentially laminated, the lead-out wirings may be corroded and broken at the edges of the sealing film by ammonium ions generated by hydrolysis of the silicon oxynitride film.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to suppress corrosion of lead wiring.

[0007] In order to achieve the above object, the display device of the present invention is a display device comprising: a base substrate; a thin-film transistor layer provided on the base substrate, the thin-film transistor layer having a first metal film and a planarization film made of an organic resin material laminated in that order; a light-emitting element layer provided on the thin-film transistor layer, in which a plurality of light-emitting elements are arranged corresponding to a plurality of sub-pixels constituting a display area; a sealing film provided on the light-emitting element layer so as to cover the plurality of light-emitting elements, the sealing film having a first silicon nitride-based inorganic sealing film and a second silicon oxynitride-based inorganic sealing film laminated in that order; a frame region provided around the display area; terminal portions provided at edges of the frame region; and a plurality of lead-out wirings formed of the first metal film in the frame region so as to be led out from the display area side to the terminal portion side, wherein the peripheral edge of the first inorganic sealing film is provided outward from the peripheral edge of the second inorganic sealing film, at least on the terminal portion side.

[0008] According to the present invention, corrosion of the lead wiring can be suppressed.

[0009] FIG. 1 is a plan view showing a schematic configuration of an organic EL display device according to a first embodiment of the present invention. FIG. 2 is a plan view of a display region of the organic EL display device according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of the organic EL display device taken along line III-III in FIG. 1. FIG. 4 is an equivalent circuit diagram of a TFT layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 5 is a cross-sectional view of an organic EL layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 6 is a cross-sectional view of a frame region of the organic EL display device taken along line VI-VI in FIG. 1. FIG. 7 is an enlarged plan view of region A in FIG. 1. FIG. 8 is a cross-sectional view of the frame region of the organic EL display device taken along line VIII-VIII in FIG. 7. FIG. 9 is a cross-sectional view of a frame region of a modified organic EL display device according to the first embodiment of the present invention, corresponding to FIG. 8. FIG. 10 is a cross-sectional view showing a first step of a sealing film forming step in a method for manufacturing an organic EL display device according to the first embodiment of the present invention. FIG. 11 is a cross-sectional view showing a second step of a sealing film forming step in a method for manufacturing an organic EL display device according to the first embodiment of the present invention.

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments.

[0011] First Embodiment FIGS. 1 to 11 show a first embodiment of a display device according to the present invention. In the following embodiments, an organic EL display device including an organic EL element layer is exemplified as a display device including a light-emitting element layer. FIG. 1 is a plan view showing a schematic configuration of an organic EL display device 50 according to this embodiment. FIG. 2 is a plan view of a display region D of the organic EL display device 50. FIG. 3 is a cross-sectional view of the organic EL display device 50 taken along line III-III in FIG. 1. FIG. 4 is an equivalent circuit diagram of a TFT layer 20 constituting the organic EL display device 50. FIG. 5 is a cross-sectional view of an organic EL layer 23 constituting the organic EL display device 50. FIG. 6 is a cross-sectional view of a frame region F of the organic EL display device 50 taken along line VI-VI in FIG. 1. FIG. 7 is an enlarged plan view of region A in FIG. 1. FIG. 8 is a cross-sectional view of the frame region F of the organic EL display device 50 taken along line VIII-VIII in FIG. 7. 9 is a cross-sectional view of a frame region F of an organic EL display device 50a as a modified example of the organic EL display device 50, and corresponds to FIG.

[0012] 1, the organic EL display device 50 includes, for example, a rectangular display area D for displaying an image, and a frame area F provided in the shape of a rectangular frame around the display area D. Note that, although the present embodiment illustrates a rectangular display area D, this rectangular shape also includes, for example, a substantially rectangular shape with arc-shaped sides, arc-shaped corners, or a shape with a notch in one of the sides.

[0013] In the display region D, a plurality of sub-pixels P are arranged in a matrix as shown in Fig. 2. In the display region D, for example, a sub-pixel P having a red light-emitting region Lr for displaying red, a sub-pixel P having a green light-emitting region Lg for displaying green, and a sub-pixel P having a blue light-emitting region Lb for displaying blue are provided adjacent to each other as shown in Fig. 2. In the display region D, one pixel is configured by, for example, three adjacent sub-pixels P having the red light-emitting region Lr, the green light-emitting region Lg, and the blue light-emitting region Lb.

[0014] A terminal portion T is provided at the end of the frame region F on the positive side in the X direction in FIG. 1 so as to extend in one direction (the Y direction in FIG. 1). Also, in the frame region F, as shown in FIG. 1, a bending portion B is provided between the display region D and the terminal portion T so as to extend in one direction (the Y direction in FIG. 1), which can be bent, for example, 180° (in a U-shape) with the Y direction in FIG. 1 as the bending axis. Also, in the frame region F, a trench G having a substantially C-shape in plan view is provided in the planarization film 19a (described later) so as to penetrate the planarization film 19a, as shown in FIGS. 1, 3, and 6. Here, the trench G is provided in a substantially C-shape in plan view so as to open on the terminal portion T side, as shown in FIG. 1.

[0015] As shown in Figures 3 and 6, the organic EL display device 50 includes a resin substrate 10 provided as a base substrate, a TFT layer 20 provided on the resin substrate 10, an organic EL element layer 30 provided as a light-emitting element layer on the TFT layer 20, and a sealing film 45 provided on the organic EL element layer 30.

[0016] The resin substrate 10 is made of, for example, polyimide resin.

[0017] As shown in FIG. 3 , the TFT layer 20 includes a base coat film 11 provided on the resin substrate layer 10, a plurality of first TFTs 9 a, a plurality of second TFTs 9 b, and a plurality of capacitors 9 c provided on the base coat film 11, and a planarization film 19 a provided on each of the first TFTs 9 a, each of the second TFTs 9 b, and each of the capacitors 9 c. As shown in FIG. 2 , the TFT layer 20 includes a plurality of gate lines 14 g extending parallel to each other in the X direction. As shown in FIG. 2 , the TFT layer 20 also includes a plurality of source lines 18 f extending parallel to each other in the Y direction. As shown in FIG. 2 , the TFT layer 20 also includes a plurality of power supply lines 18 g extending parallel to each other in the Y direction. Each power supply line 18 g is adjacent to each of the source lines 18 f. 4, the TFT layer 20 includes a first TFT 9a, a second TFT 9b, and a capacitor 9c for each subpixel P. In the TFT layer 20, as shown in Fig. 3, the following are stacked in order on a resin substrate 10: a base coat film 11, a semiconductor film that will become a semiconductor layer 12a (to be described later) and the like, a gate insulating film 13 (to be described later) and a third metal film that will become a gate line 14g and the like, a first interlayer insulating film 15 (to be described later), a second metal film that will become an upper conductive layer 16c (to be described later), a second interlayer insulating film 17 (to be described later) provided as a first inorganic insulating film, a first metal film that will become a source line 18f, a power line 18g, and the like, and a planarization film 19a.

[0018] The base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 are each composed of a single layer or a multilayer film of an inorganic insulating film such as silicon nitride, silicon oxide, or silicon oxynitride.

[0019] 4, the first TFT 9a is electrically connected to the corresponding gate line 14g, source line 18f, and second TFT 9b in each subpixel P. Here, as shown in Fig. 3, the first TFT 9a includes a semiconductor layer 12a provided on a base coat film 11, a gate electrode 14a provided on the semiconductor layer 12a via a gate insulating film 13, and a source electrode 18a and a drain electrode 18b provided on a second interlayer insulating film 17 so as to be spaced apart from each other.

[0020] The semiconductor layer 12a and a semiconductor layer 12b (described later) are formed of a semiconductor film made of polysilicon such as low temperature polysilicon (LTPS). The semiconductor layer 12a (12b) includes a source region and a drain region that are defined to be spaced apart from each other, and a channel region that is defined between the source region and the drain region.

[0021] The gate electrode 14a is provided so as to overlap the channel region of the semiconductor layer 12a and is configured to control conduction between the source region and the drain region of the semiconductor layer 12a. Here, the gate electrode 14a and a gate electrode 14b, which will be described later, are formed of a third metal film, similar to the gate line 14g and the like.

[0022] 3, the source electrode 18a and the drain electrode 18b are electrically connected to the source region and the drain region of the semiconductor layer 12a, respectively, through contact holes formed in the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17. Here, the source electrode 18a and the drain electrode 18b, as well as the source electrode 18c and the drain electrode 18d described later, are formed of a first metal film, similar to the source line 18f, the power supply line 18g, and the like.

[0023] 4, the second TFT 9b is electrically connected to the corresponding first TFT 9a, a power supply line 18g, and an organic EL element 25 (described later) in each subpixel P. Here, the second TFT 9b includes a semiconductor layer 12b provided on the base coat film 11, a gate electrode 14b provided on the semiconductor layer 12b via a gate insulating film 13, and a source electrode 18c and a drain electrode 18d provided spaced apart from each other on the second interlayer insulating film 17, as shown in FIG.

[0024] The gate electrode 14b is provided so as to overlap the channel region of the semiconductor layer 12b, and is configured to control conduction between the source region and the drain region of the semiconductor layer 12b.

[0025] As shown in FIG. 3, the source electrode 18c and the drain electrode 18d are electrically connected to the source region and the drain region of the semiconductor layer 12b, respectively, through contact holes formed in the stacked film of the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17.

[0026] In this embodiment, the semiconductor layers 12a and 12b are formed of a semiconductor film made of polysilicon, but the semiconductor layers 12a and 12b may be formed of a semiconductor film made of an oxide semiconductor such as In-Ga-Zn-O. Furthermore, the TFT layer 20 may have a hybrid structure in which a TFT having a semiconductor layer made of polysilicon and a TFT having a semiconductor layer made of an oxide semiconductor are provided.

[0027] As shown in Fig. 4, the capacitor 9c is electrically connected to the corresponding first TFT 9a and power supply line 18g in each subpixel P. Here, as shown in Fig. 3, the capacitor 9c includes a lower conductive layer 14c formed of a third metal film, an upper conductive layer 16c formed of a second metal film, and a first interlayer insulating film 15 provided between the lower conductive layer 14c and the upper conductive layer 16c. Note that the upper conductive layer 16c is electrically connected to the power supply line 18g via a contact hole formed in the second interlayer insulating film 17, as shown in Fig. 3.

[0028] The planarizing film 19a has a flat surface in the display region D and is made of an organic resin material such as polyimide resin or acrylic resin.

[0029] 3 , the organic EL element layer 30 includes a plurality of organic EL elements 25 arranged in a matrix as a plurality of light-emitting elements corresponding to a plurality of sub-pixels P, and edge covers 22 a provided in a lattice pattern common to all the sub-pixels P so as to cover peripheral edges of first electrodes 21 a (described later) of each of the organic EL elements 25. Note that, although the present embodiment illustrates a configuration in which each of the plurality of light-emitting elements is an organic EL element 25, at least one of the plurality of light-emitting elements may be an organic EL element 25.

[0030] As shown in Figure 3, in each subpixel P, the organic EL element 25 includes a first electrode 21a provided on the planarization film 19a of the TFT layer 20, an organic EL layer 23 provided on the first electrode 21a, and a second electrode 24 provided on the organic EL layer 23.

[0031] As shown in FIG. 3 , the first electrode 21 a is electrically connected to the drain electrode 18 d of the second TFT 9 b of each subpixel P through a contact hole formed in the planarization film 19 a. The first electrode 21 a has a function of injecting holes (positive holes) into the organic EL layer 23. The first electrode 21 a is preferably formed of a material with a large work function to improve the efficiency of hole injection into the organic EL layer 23. Examples of materials that can be used to form the first electrode 21 a include metal materials such as silver (Ag), aluminum (Al), vanadium (V), cobalt (Co), nickel (Ni), tungsten (W), gold (Au), titanium (Ti), ruthenium (Ru), manganese (Mn), indium (In), ytterbium (Yb), lithium fluoride (LiF), platinum (Pt), palladium (Pd), molybdenum (Mo), iridium (Ir), and tin (Sn). The material constituting the first electrode 21a is, for example, astatine (At) / astatine oxide (AtO ２ The first electrode 21a may be made of an alloy of tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), or another conductive oxide. The first electrode 21a may be formed by stacking multiple layers made of the above materials. Examples of compound materials with a large work function include indium tin oxide (ITO) and indium zinc oxide (IZO).

[0032] As shown in FIG. 5, the organic EL layer 23 includes a hole injection layer 1, a hole transport layer 2, a light emitting layer 3, an electron transport layer 4, and an electron injection layer 5, which are provided in this order on the first electrode 21a.

[0033] The hole injection layer 1, also called an anode buffer layer, has a function of bringing the energy levels of the first electrode 21a and the organic EL layer 23 closer to each other and improving the efficiency of hole injection from the first electrode 21a to the organic EL layer 23. Examples of materials constituting the hole injection layer 1 include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, phenylenediamine derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, and stilbene derivatives.

[0034] The hole transport layer 2 has a function of improving the efficiency of transporting holes from the first electrode 21a to the organic EL layer 23. Here, examples of materials constituting the hole transport layer 2 include porphyrin derivatives, aromatic tertiary amine compounds, styrylamine derivatives, polyvinylcarbazole, poly-p-phenylenevinylene, polysilane, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amine-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, hydrogenated amorphous silicon, hydrogenated amorphous silicon carbide, zinc sulfide, and zinc selenide.

[0035] The light-emitting layer 3 is a region into which holes and electrons are injected from the first electrode 21 a and the second electrode 24, respectively, and where the holes and electrons recombine when a voltage is applied by the first electrode 21 a and the second electrode 24. Here, the light-emitting layer 3 is made of a material with high luminous efficiency. Examples of materials that can be used to form the light-emitting layer 3 include metal oxinoid compounds [8-hydroxyquinoline metal complexes], naphthalene derivatives, anthracene derivatives, diphenylethylene derivatives, vinylacetone derivatives, triphenylamine derivatives, butadiene derivatives, coumarin derivatives, benzoxazole derivatives, oxadiazole derivatives, oxazole derivatives, benzimidazole derivatives, thiadiazole derivatives, benzthiazole derivatives, styryl derivatives, styrylamine derivatives, bisstyrylbenzene derivatives, trisstyrylbenzene derivatives, perylene derivatives, perinone derivatives, aminopyrene derivatives, pyridine derivatives, rhodamine derivatives, aquidin derivatives, phenoxazone, quinacridone derivatives, rubrene, poly-p-phenylenevinylene, and polysilane.

[0036] The electron transport layer 4 has a function of efficiently transferring electrons to the light-emitting layer 3. Examples of materials constituting the electron transport layer 4 include organic compounds such as oxadiazole derivatives, triazole derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, tetracyanoanthraquinodimethane derivatives, diphenoquinone derivatives, fluorenone derivatives, silole derivatives, and metal oxinoid compounds.

[0037] The electron injection layer 5 has a function of bringing the energy levels of the second electrode 24 and the organic EL layer 23 closer to each other and improving the efficiency of electron injection from the second electrode 24 to the organic EL layer 23, and this function can reduce the driving voltage of the organic EL element 25. The electron injection layer 5 is also called a cathode buffer layer. Here, examples of materials constituting the electron injection layer 5 include lithium fluoride (LiF), magnesium fluoride (MgF ２ ), calcium fluoride (CaF ２ ), strontium fluoride (SrF ２ ), barium fluoride (BaF ２), inorganic alkali compounds such as aluminum oxide (Al ２ O ３ ), strontium oxide (SrO), etc.

[0038] As shown in FIG. 3 , the second electrode 24 is provided to cover each organic EL layer 23 and the edge cover 22 a. The second electrode 24 has a function of injecting electrons into the organic EL layer 23. The second electrode 24 is preferably made of a material with a small work function to improve the efficiency of electron injection into the organic EL layer 23. Examples of materials that can be used for the second electrode 24 include silver (Ag), aluminum (Al), vanadium (V), cobalt (Co), nickel (Ni), tungsten (W), gold (Au), calcium (Ca), titanium (Ti), yttrium (Y), sodium (Na), ruthenium (Ru), manganese (Mn), indium (In), magnesium (Mg), lithium (Li), ytterbium (Yb), and lithium fluoride (LiF). The second electrode 24 may be made of, for example, magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), sodium (Na) / potassium (K), or astatine (At) / astatine oxide (AtO ２ The second electrode 24 may be formed of an alloy such as lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), or lithium fluoride (LiF) / calcium (Ca) / aluminum (Al). The second electrode 24 may be formed of a conductive oxide such as tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), or indium zinc oxide (IZO). The second electrode 24 may be formed by stacking multiple layers made of the above materials. Examples of materials with a low work function include magnesium (Mg), lithium (Li), lithium fluoride (LiF), magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), sodium (Na) / potassium (K), lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), and lithium fluoride (LiF) / calcium (Ca) / aluminum (Al).

[0039] The edge cover 22a is formed of an organic resin material such as polyimide resin, acrylic resin, etc. Here, as shown in Fig. 3, a part of the surface of the edge cover 22a protrudes upward in the drawing and serves as an island-shaped pixel photospacer.

[0040] 3 and 6 , the sealing film 45 is provided so as to cover the organic EL element 25 of each sub-pixel P, and has the function of protecting the organic EL layer 23 from moisture, oxygen, etc. Here, in the sealing film 45, the first inorganic sealing film 41, the second inorganic sealing film 42, the organic sealing film 43, and the third inorganic sealing film 44 are laminated in this order on the inner periphery of the display region D and the frame region F, as shown in Fig. 3 and 6 , and the first inorganic sealing film 41, the second inorganic sealing film 42, and the third inorganic sealing film 44 are laminated in this order on the outer periphery of the frame region F, as shown in Fig. 6 and 8 .

[0041] The first inorganic sealing film 41 is made of, for example, a silicon nitride-based inorganic insulating film.

[0042] The second inorganic sealing film 42 is made of, for example, a silicon oxynitride-based inorganic insulating film. Here, as shown in FIGS. 6 and 8 , the peripheral edge 41 e of the first inorganic sealing film 41 is provided outward (on the positive side in the X direction in FIGS. 6 and 8 ) from the peripheral edge 42 e of the second inorganic sealing film 42 (for example, so as to protrude by at least 20 μm or more) along the entire periphery. Therefore, even if the silicon oxynitride-based second inorganic sealing film 42 is hydrolyzed by moisture in the outside air to generate ammonium ions, the silicon nitride-based first inorganic sealing film 41 can suppress the diffusion of the ammonium ions toward the planarization film 19 d.

[0043] The organic sealing film 43 is formed from an organic resin material such as an acrylic resin, an epoxy resin, a silicone resin, a polyurea resin, a parylene resin, a polyimide resin, or a polyamide resin.

[0044] The third inorganic sealing film 44 is made of an inorganic insulating film such as a silicon nitride film, a silicon oxide film, or a silicon oxynitride film.

[0045] As shown in Figures 1 and 6, the organic EL display device 50 is provided with a first dam wall Wa in a frame shape in the frame region F so as to surround the display region D and overlap the peripheral edge of the organic sealing film 43, and a second dam wall Wb in a frame shape so as to surround the first dam wall Wa.

[0046] 6, the first damming wall Wa includes a lower resin layer 19b formed in the same layer and made of the same material as the planarizing film 19a, and an upper resin layer 22c provided on the lower resin layer 19b via a metal layer 21b, the upper resin layer 22c being formed in the same layer and made of the same material as the edge cover 22a. As shown in FIG. 6, the metal layer 21b is provided in the frame region F in a generally C-shaped or rectangular shape in plan view so as to overlap the trench G, the first damming wall Wa, and the second damming wall Wb. The metal layer 21b is formed in the same layer and made of the same material as the first electrode 21a.

[0047] As shown in Figure 6, the second dam wall Wb comprises a lower resin layer 19c formed in the same layer and made of the same material as the planarization film 19a, and an upper resin layer 22d provided on the lower resin layer 19c via a metal layer 21b and formed in the same layer and made of the same material as the edge cover 22a.

[0048] 1 , the organic EL display device 50 includes first frame wiring 18h that extends widely in the opening of the trench G in the frame region F, extends linearly inside the trench G in the Y direction on the display region D side, and has both ends on the bent portion B side extending in the X direction to reach a terminal portion T. Here, the first frame wiring 18h is electrically connected to a power supply line 18g on the display region D side of the frame region F, and is configured so that a high power supply voltage (ELVDD) is input to the terminal portion T. The first frame wiring 18h and second frame wiring 18i, which will be described later, are formed of a first metal film, similar to the source line 18f and the power supply line 18g.

[0049] 1, the organic EL display device 50 includes a second frame wiring 18i that is provided in a generally C-shaped configuration in plan view outside the trench G in the frame region F so as to overlap the first dam wall Wa and the second dam wall Wb, and has both ends extending in the X direction in the figure to reach the terminal portion T. Here, as shown in FIG. 6, the second frame wiring 18i is electrically connected to the second electrode 24 via the metal layer 21b formed in the trench G, and is configured so that a low power supply voltage (ELVSS) is input to the terminal portion T.

[0050] 3 and 6, the organic EL display device 50 includes a peripheral photo-spacer 22b that protrudes upward in the frame region F. Here, the peripheral photo-spacer 22b is formed in the same layer as the edge cover 22a and made of the same material.

[0051] 8 , the organic EL display device 50 includes a resin filling film 8 provided at the folding portion B of the frame region F so as to fill slits S formed in the base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17, a plurality of lead-out wirings 18j provided on the resin filling film 8 and the second interlayer insulating film 17, and a planarization film 19d provided so as to cover each lead-out wiring 18j. Note that, in the present embodiment, the organic EL display device 50 is illustrated as having slits S formed in the base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 at the folding portion B, and the resin filling film 8 provided so as to fill the slits S. However, as shown in FIG. 9 , an organic EL display device 50a or the like may be used in which the slits S are not formed in the base coat film 11 and the second interlayer insulating film 17, and the resin filling film 8 is omitted.

[0052] As shown in FIG. 8, the slit S is provided in the form of a groove that extends along the direction in which the bent portion B extends, penetrating the base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17, exposing the surface of the resin substrate 10.

[0053] The resin filling film 8 is made of an organic resin material such as polyimide resin or acrylic resin.

[0054] The plurality of lead-out wirings 18j are provided so as to be drawn out from the display region D side to the terminal portion T side, and as shown in FIG. 7 , are provided so as to extend parallel to each other in a direction perpendicular to the direction in which the bent portion B extends. Here, each lead-out wiring 18j, like the source lines 18f and the power supply lines 18g, is formed of a first metal film. Furthermore, as shown in FIGS. 7 and 8 , the ends of the plurality of lead-out wirings 18j on the display region D side are electrically connected to the plurality of relay wirings 16j through contact holes C formed in the second interlayer insulating film 17. Note that, like the upper conductive layer 16c and the like, each relay wiring 16j is formed of a second metal film and electrically connected to the display wiring (such as the source lines 18f) arranged in the display region D. Furthermore, the ends of the plurality of lead-out wirings 18j on the terminal portion T side are provided so as to reach the terminal portion T and are exposed from the planarization film 19d at the terminal portion T to form terminals. Furthermore, the multiple relay wirings 16j extending parallel to each other may be formed of a third metal film, and for example, relay wirings 16j formed of the second metal film and relay wirings 16j formed of the third metal film may be arranged alternately in a direction perpendicular to the direction in which the wiring extends.

[0055] The planarizing film 19d is provided in a strip shape along the direction of extension of the bent portion B in the bent portion B. The planarizing film 19d is formed in the same layer as the planarizing film 19a and made of the same material.

[0056] As described above, in the sealing film 45, the peripheral edge 41 e of the first inorganic sealing film 41 is located outside the peripheral edge 42 e of the second inorganic sealing film 42 along the entire periphery, so that even if moisture in the outside air causes hydrolysis of the silicon oxynitride-based second inorganic sealing film 42 to generate ammonium ions, the diffusion of the ammonium ions toward the planarization film 19 d can be suppressed by the silicon nitride-based first inorganic sealing film 41. This makes it difficult for the ammonium ions to reach the vicinity of the contact hole C that electrically connects the lead-out wiring 18 j and the relay wiring 16 j, thereby suppressing corrosion of the lead-out wiring 18 j near the contact hole C and suppressing disconnection of the lead-out wiring 18 j.

[0057] In the organic EL display device 50 configured as described above, in each subpixel P, a gate signal is input to the first TFT 9a via the gate line 14g to turn the first TFT 9a on, a data signal is written to the gate electrode 14b and capacitor 9c of the second TFT 9b via the source line 18f, and a current from the power supply line 18g corresponding to the gate voltage of the second TFT 9b is supplied to the organic EL layer 23 of the organic EL element 25, causing the light-emitting layer 3 of the organic EL layer 23 to emit light, thereby displaying an image. Note that in the organic EL display device 50, even if the first TFT 9a is turned off, the gate voltage of the second TFT 9b is held by the capacitor 9c, so that light emission by the light-emitting layer 3 is maintained until a gate signal for the next frame is input.

[0058] Next, a method for manufacturing the organic EL display device 50 of this embodiment will be described. The method for manufacturing the organic EL display device 50 of this embodiment includes a TFT layer forming step, an organic EL element layer forming step, and a sealing film forming step including first, second, third, and fourth steps. Here, Figures 10 and 11 are cross-sectional views showing the first and second steps of the sealing film forming step in the method for manufacturing the organic EL display device 50, respectively.

[0059] <TFT Layer Forming Process> First, for example, a non-photosensitive polyimide resin (about 6 μm thick) is applied onto a glass substrate, and then the applied film is pre-baked and post-baked to form a resin substrate 10 .

[0060] Next, a silicon oxide film (approximately 500 nm thick) and a silicon nitride film (approximately 100 nm thick) are sequentially formed on the surface of the substrate on which the resin substrate 10 is formed, for example, by plasma CVD (chemical vapor deposition) method, thereby forming a base coat film 11.

[0061] Thereafter, an amorphous silicon film (about 50 nm thick) is formed by plasma CVD on the surface of the substrate on which the base coat film 11 has been formed, and the amorphous silicon film is crystallized by laser annealing or the like to form a semiconductor film of polysilicon film, and then the semiconductor film is patterned to form semiconductor layers 12 a and 12 b, etc.

[0062] Furthermore, a silicon oxide film (about 100 nm) or the like is formed by, for example, plasma CVD on the substrate surface on which the semiconductor layer 12a and the like are formed, to form a gate insulating film 13 so as to cover the semiconductor layer 12a and the like.

[0063] Next, a third metal film such as a molybdenum film (about 250 nm thick) is formed on the surface of the substrate on which the gate insulating film 13 has been formed, for example, by sputtering, and then the third metal film is patterned to form the gate line 14g, gate electrodes 14a and 14b, lower conductive layer 14c, etc.

[0064] Thereafter, impurity ions are doped using the gate electrodes 14a and 14b as a mask to make parts of the semiconductor layers 12a and 12b conductive.

[0065] Furthermore, a silicon nitride film (about 100 nm thick) is formed by, for example, plasma CVD on the substrate surface where parts of the semiconductor layer 12a etc. have been made conductive, thereby forming a first interlayer insulating film 15.

[0066] Next, a second metal film such as a molybdenum film (about 250 nm thick) is formed on the surface of the substrate on which the first interlayer insulating film 15 is formed, for example, by sputtering, and then the second metal film is patterned to form the upper conductive layer 16c, relay wiring 16j, etc.

[0067] Thereafter, a silicon oxide film (approximately 300 nm thick) and a silicon nitride film (approximately 200 nm thick) are sequentially formed on the substrate surface on which the upper conductive layer 16c and the like are formed, for example, by plasma CVD, thereby forming a second interlayer insulating film 17.

[0068] Furthermore, the gate insulating film 13, the first interlayer insulating film 15 and the second interlayer insulating film 17 are appropriately patterned to form contact holes.

[0069] Next, at the bending portion B, the stacked film of the base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 is removed, and a slit S is formed in the base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17.

[0070] Thereafter, for example, a photosensitive polyimide resin is applied to the surface of the substrate on which the slit S is formed, and then the applied film is pre-baked, exposed to light, developed, and post-baked to form a resin-filled film 8 that fills the slit S at the bending portion B.

[0071] Furthermore, on the surface of the substrate on which the resin filling film 8 has been formed, a titanium-based metal film (thickness: about 50 nm), an aluminum-based metal film (thickness: about 600 nm), and a titanium-based metal film (thickness: about 50 nm) are sequentially formed by, for example, a sputtering method, and then these metal laminated films are patterned to form a source line 18f, a power line 18g, source electrodes 18a and 18c, drain electrodes 18b and 18d, a first frame wiring 18h, a second frame wiring 18i, a lead wiring 18j, and the like.

[0072] Finally, a photosensitive polyimide resin (about 2.5 μm thick) is applied to the substrate surface on which the source lines 18 f and the like are formed, for example, by spin coating or slit coating, and then the applied film is pre-baked, exposed to light, developed, and post-baked to form planarizing films 19 a and 19 d and lower resin layers 19 b and 19 c.

[0073] In this manner, the TFT layer 20 can be formed.

[0074] <Organic EL Element Layer Forming Process> First, on the planarization film 19a of the TFT layer 20 formed in the TFT layer forming process, a first electrode 21a, an edge cover 22a, an organic EL layer 23 (hole injection layer 1, hole transport layer 2, organic light-emitting layer 3, electron transport layer 4, electron injection layer 5), and a second electrode 24 are formed by a well-known method to form the organic EL element layer 30. Here, when forming the edge cover 22a, for example, a polyimide-based photosensitive resin film (with a thickness of about 2 μm) is applied by a spin coating method or a slit coating method, and then the applied film is pre-baked, exposed to light, developed, and post-baked to form the edge cover 22a, and also form the peripheral photospacers 22b, the upper resin layers 22c and 22d, etc.

[0075] In this manner, the organic EL element layer 30 can be formed.

[0076] <Sealing film forming process> First, as shown in FIG. 10 , on the surface of the substrate on which the organic EL element layer 30 formed in the organic EL element layer forming process has been formed, an inorganic insulating film (with a thickness of about 100 nm) such as a silicon nitride film is formed by, for example, a plasma CVD method using a film formation mask Ma to form a first inorganic sealing film 41 (first process).

[0077] 11, an inorganic insulating film (about 1400 nm thick) such as a silicon oxynitride film is formed on the substrate surface on which the first inorganic sealing film 41 has been formed by, for example, plasma CVD using a deposition mask Mb to form the second inorganic sealing film 42 (second step). The opening area of ​​the deposition mask Mb is smaller than the opening area of ​​the deposition mask Ma.

[0078] Thereafter, an organic resin material such as acrylic resin (about 10 μm thick) is deposited by, for example, an inkjet method on the substrate surface on which the second inorganic sealing film 42 has been formed, to form an organic sealing film 43 (third step).

[0079] Furthermore, using a film formation mask Ma, an inorganic insulating film (approximately 500 nm thick) such as a silicon nitride film is formed by plasma CVD on the substrate surface on which the organic sealing film 43 has been formed, thereby forming a third inorganic sealing film 44 and thereby forming a sealing film 45 (fourth step).

[0080] Finally, a protective sheet (not shown) is attached to the surface of the substrate on which the sealing film 45 is formed, and then laser light is irradiated from the glass substrate side of the resin substrate 10 to peel the glass substrate from the underside of the resin substrate 10, and further a protective sheet (not shown) is attached to the underside of the resin substrate 10 from which the glass substrate has been peeled.

[0081] In this manner, the organic EL display device 50 of this embodiment can be manufactured.

[0082] In this embodiment, an organic EL display device 50 and a manufacturing method thereof are illustrated in which the peripheral edge 41a of the first inorganic sealing film 41 is formed outside the peripheral edge 42e of the second inorganic sealing film 42 around the entire circumference using two types of first film deposition masks Ma and second film deposition masks Mb with different opening areas.However, for example, after forming the first inorganic sealing film 41 using the first film deposition mask Ma, the first film deposition mask Ma may be shifted in a direction away from the terminal portion T to form the second inorganic sealing film 42, so that the peripheral edge 41e of the first inorganic sealing film 41 is located outside the peripheral edge 42e of the second inorganic sealing film 42 between the display area D and the folding portion B. That is, at least on the terminal portion T side, if the peripheral edge 41 e of the first inorganic sealing film 41 is located outside the peripheral edge 42 e of the second inorganic sealing film 42, even if ammonium ions are generated by hydrolysis of the silicon oxynitride-based second inorganic sealing film 42, the ammonium ions can be prevented from reaching the vicinity of the contact hole C for electrically connecting the lead wiring 18 j and the relay wiring 16 j. Furthermore, by using one type of deposition mask (e.g., the first deposition mask Ma) and changing the distance from the substrate to be processed, the deposition conditions, etc., the peripheral edge 41 a of the first inorganic sealing film 41 may be formed outside the peripheral edge 42 e of the second inorganic sealing film 42 along the entire periphery. Furthermore, although the present embodiment illustrates a manufacturing method in which the first inorganic sealing film 41 and the second inorganic sealing film 42 are formed using the first deposition mask Ma and the second deposition mask Mb, the first inorganic sealing film 41 and the second inorganic sealing film 42 may also be formed by patterning using photolithography and etching.

[0083] As described above, in the organic EL display device 50 of this embodiment, in the sealing film 45, the peripheral edge 41 e of the first inorganic sealing film 41 is located outside the peripheral edge 42 e of the second inorganic sealing film 42 along the entire periphery. Therefore, even if moisture in the outside air hydrolyzes the silicon oxynitride-based second inorganic sealing film 42 to generate ammonium ions, the silicon nitride-based first inorganic sealing film 41 can suppress the diffusion of the ammonium ions toward the planarization film 19 d. This makes it difficult for the ammonium ions to reach the vicinity of the contact hole C that electrically connects the lead-out wiring 18 j and the relay wiring 16 j, thereby suppressing corrosion of the lead-out wiring 18 j near the contact hole C and suppressing disconnection of the lead-out wiring 18 j.

[0084] Furthermore, according to the organic EL display device 50 of this embodiment, a silicon oxynitride-based second inorganic sealing film 42 is provided on the resin substrate 10 side of the organic sealing film 43, thereby improving the applicability of the ink that will become the organic sealing film 43 formed by depositing it on the second inorganic sealing film 42 using an inkjet method.

[0085] Other Embodiments In the above-described embodiments, the organic EL layer has a five-layer laminated structure including a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. However, the organic EL layer may have a three-layer laminated structure including, for example, a hole injection layer / hole transport layer, a light-emitting layer, and an electron transport layer / electron injection layer.

[0086] In addition, in each of the above embodiments, an organic EL display device in which the first electrode is an anode and the second electrode is a cathode is exemplified. However, the present invention can also be applied to an organic EL display device in which the stacked structure of the organic EL layer is reversed, and the first electrode is a cathode and the second electrode is an anode.

[0087] Furthermore, in each of the above embodiments, an organic EL display device is exemplified in which the electrode of the TFT connected to the first electrode is used as the drain electrode, but the present invention can also be applied to an organic EL display device in which the electrode of the TFT connected to the first electrode is called the source electrode.

[0088] Furthermore, in each of the above embodiments, an organic EL display device has been described as an example of a display device. However, the present invention can be applied to a display device including a plurality of light-emitting elements driven by current, and can be applied to, for example, a display device including QLEDs (Quantum-dot light emitting diodes), which are light-emitting elements using a quantum dot-containing layer.

[0089] As described above, the present invention is useful for flexible display devices.

[0090] B Bending portion C Contact hole D Display area F Frame area P Sub-pixel T Terminal portion Wa First damming wall 10 Resin substrate (base substrate) 16j Relay wiring 17 Second interlayer insulating film (first inorganic insulating film) 18j Lead wiring 19a, 19b Planarization film 20 TFT layer (thin film transistor layer) 25 Organic EL element (organic electroluminescence element, light-emitting element) 30 Organic EL element layer (light-emitting element layer) 41 First inorganic sealing film 42 Second inorganic sealing film 43 Organic sealing film 44 Third inorganic sealing film 45 Sealing film 50, 50a Organic EL display device

Claims

1. A display device comprising: a base substrate; a thin film transistor layer provided on the base substrate, the thin film transistor layer being formed by sequentially laminating a first metal film and a planarization film made of an organic resin material; a light emitting element layer provided on the thin film transistor layer, the light emitting element layer having a plurality of light emitting elements arranged corresponding to a plurality of sub-pixels constituting a display area; a sealing film provided on the light emitting element layer so as to cover the plurality of light emitting elements, the sealing film being formed by sequentially laminating a first inorganic sealing film made of silicon nitride and a second inorganic sealing film made of silicon oxynitride; a frame region provided around the periphery of the display area; terminal portions provided at edges of the frame region; and a plurality of lead-out wirings formed of the first metal film in the frame region so as to be led out from the display area side to the terminal portion side, wherein the peripheral edge of the first inorganic sealing film is provided outward from the peripheral edge of the second inorganic sealing film, at least on the terminal portion side.

2. A display device according to claim 1, wherein a bent portion is provided between the display area and the terminal portion so as to extend in one direction, and between the display area and the bent portion, the peripheral edge of the first inorganic sealing film is located outside the peripheral edge of the second inorganic sealing film.

3. A display device according to claim 1 or 2, characterized in that the peripheral edge of the first inorganic sealing film is located outside the peripheral edge of the second inorganic sealing film along the entire periphery.

4. A display device according to any one of claims 1 to 3, characterized in that the first metal film is formed from a laminated film in which a titanium-based metal film, an aluminum-based metal film, and a titanium-based metal film are laminated in this order.

5. A display device according to claim 2, wherein the thin film transistor layer is formed by laminating a second metal film, a first inorganic insulating film, the first metal film and the planarizing film in this order, and the plurality of lead-out wirings are electrically connected to a plurality of relay wirings formed by the second metal film on the display area side between the display area and the bent portion via contact holes formed in the first inorganic insulating film.

6. A display device according to any one of claims 1 to 5, wherein the sealing film comprises a third inorganic sealing film laminated on the second inorganic sealing film.

7. A display device according to claim 6, wherein the sealing film comprises an organic sealing film provided between the second inorganic sealing film and the third inorganic sealing film at least in the display region.

8. A display device according to claim 7, wherein a blocking wall is provided in the frame region in a frame shape so as to surround the display region and overlap the peripheral edge of the organic sealing film.

9. The display device according to any one of claims 1 to 8, wherein at least one of the plurality of light-emitting elements is an organic electroluminescence element.

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