WO2020053923A1

WO2020053923A1 - Display device

Info

Publication number: WO2020053923A1
Application number: PCT/JP2018/033400
Authority: WO
Inventors: 貴翁斉藤; 昌彦三輪; 庸輔神崎; 雅貴山中; 屹孫; 誠二金子
Original assignee: シャープ株式会社
Priority date: 2018-09-10
Filing date: 2018-09-10
Publication date: 2020-03-19

Abstract

A display device according to the present invention is provided with: a base substrate (10); a TFT layer (20) which is provided on the base substrate (10); a light emitting element which is provided on the TFT layer (20) and constitutes a display area; a sealing film (30) which is provided so as to cover the light emitting element, while being composed of a first inorganic insulating film (26), an organic film (27) and a second inorganic insulating film (28), said films being sequentially stacked; and weir walls (Wa, Wb) which are provided so as to surround the display area in a frame area (F) that is positioned around the display area. The TFT layer (20)-side surface of the base substrate (10) is provided with a recessed part (Ca) along the weir walls (Wa, Wb) in the frame area (F).

Description

Display device

(4) The present invention relates to a display device.

In recent years, self-luminous organic EL display devices using organic EL (electroluminescence) elements have attracted attention as display devices replacing liquid crystal display devices. Here, in the organic EL display device, in order to suppress the deterioration of the organic EL element due to mixing of moisture, oxygen, or the like, a sealing film that covers the organic EL element is formed by a stacked film of an inorganic film and an organic film. Has been proposed.

For example, Patent Literature 1 includes a sealing film having a laminated structure in which an inorganic film formed by a chemical vapor deposition (CVD) method or the like and an organic film formed by an inkjet method or the like are alternately arranged. A display device is disclosed.

JP 2014-86415 A

By the way, when an organic film constituting a sealing film is formed by an ink-jet method as in the display device disclosed in Patent Document 1, a frame region around a display region provided with an organic EL element is provided. It is necessary to provide a damming wall for damping the ink that will become the organic film. Here, in the frame area, the more the blocking wall is separated from the peripheral edge of the display area, the more the amount of ink that can be blocked by the blocking wall increases, and the more the blocking effect of the ink by the blocking wall increases. Since the width of the frame area becomes wider by that amount, there is room for improvement.

The present invention has been made in view of the above point, and an object of the present invention is to suppress the spread of the width of the frame region and enhance the effect of blocking the ink by the blocking wall.

In order to achieve the above object, a display device according to the present invention includes a base substrate, a TFT layer provided on the base substrate, a light emitting element provided on the TFT layer, and forming a display region, A sealing film provided so as to cover the light emitting element, in which a first inorganic insulating film, an organic film, and a second inorganic insulating film are sequentially laminated; and a frame region around the display region so as to surround the display region. A display device provided with a blocking wall provided in the frame region, wherein a recess is provided along a surface of the base substrate on the TFT layer side along the blocking wall. And

According to the present invention, in the frame region, the concave portion is provided along the dam wall on the surface of the base substrate on the TFT layer side. The ink blocking effect can be enhanced.

FIG. 1 is a plan view showing a schematic configuration of the organic EL display device according to the first embodiment of the present invention. FIG. 2 is a plan view of a display area of the organic EL display device according to the first embodiment of the present invention. FIG. 3 is a sectional view of the organic EL display device taken along line III-III in FIG. FIG. 4 is an equivalent circuit diagram illustrating a TFT layer included in the organic EL display device according to the first embodiment of the present invention. FIG. 5 is a cross-sectional view illustrating an organic EL layer included in the organic EL display device according to the first embodiment of the present invention. FIG. 6 is a cross-sectional view of the frame region of the organic EL display device along the line VI-VI in FIG. FIG. 7 is a cross-sectional view of the frame region of the organic EL display device along the line VII-VII in FIG. FIG. 8 is a plan view illustrating a schematic configuration of the organic EL display device according to the second embodiment of the present invention. FIG. 9 is a cross-sectional view of the frame region of the organic EL display device along line IX-IX in FIG. FIG. 10 is a cross-sectional view of the frame region of the organic EL display device taken along line XX in FIG. FIG. 11 is a plan view showing a schematic configuration of a modification of the organic EL display device according to the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiments.

<< 1st Embodiment >>
1 to 7 show a first embodiment of a display device according to the present invention. In the following embodiments, an organic EL display device having an organic EL element will be exemplified as a display device having a light emitting element. Here, FIG. 1 is a plan view showing a schematic configuration of the organic EL display device 50a of the present embodiment. FIG. 2 is a plan view of a display area D of the organic EL display device 50a. FIG. 3 is a cross-sectional view of the organic EL display device 50a along the line III-III in FIG. FIG. 4 is an equivalent circuit diagram showing the TFT layer 20 constituting the organic EL display device 50a. FIG. 5 is a sectional view showing the organic EL layer 23 constituting the organic EL display device 50a. 6 and 7 are cross-sectional views of the frame region F of the organic EL display device 50a taken along lines VI-VI and VII-VII in FIG.

As shown in FIG. 1, the organic EL display device 50a includes, for example, a display region D provided in a rectangular shape for displaying an image, and a frame region F provided in a rectangular frame shape around the display region D. ing. In the present embodiment, the rectangular display area D is illustrated, but the rectangular shape may be, for example, a shape in which a side is an arc, a shape in which a corner is in an arc, or a part of a side. A substantially rectangular shape such as a shape with a notch is also included.

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

端子 A terminal portion T is provided on one side (the right side in FIG. 1) of the frame region F. Also, in the frame area F, as shown in FIG. 1, between the display area D and the terminal portion T, it is possible to bend (in a U-shape), for example, 180 degrees (U-shape) the bending axis in the vertical direction in the figure. The bent portion B is provided so as to extend in one direction (vertical direction in the figure). In the frame region F, a substantially C-shaped trench G is provided in a flattening film 19a described later so as to penetrate the flattening film 19a as shown in FIGS. Here, as shown in FIG. 1, the trench G is provided in a substantially C-shape such that the terminal portion T side is opened in plan view.

As shown in FIGS. 3, 6, and 7, the organic EL display device 50a includes a base substrate 10, a thin film transistor (TFT) layer 20 provided on the base substrate 10, and a light emitting element on the TFT layer 20. And an organic EL element 25 constituting the display region D, and a sealing film 30 provided so as to cover the organic EL element 25.

As shown in FIGS. 3, 6, and 7, the base substrate 10 includes a first resin layer 6 provided on the side opposite to the TFT layer 20, a second resin layer 8 provided on the side of the TFT layer 20, An inorganic insulating film provided between the first resin layer and the second resin layer; Here, the first resin layer 6 and the second resin layer 8 are formed of, for example, a polyimide resin to a thickness of about 5 μm. The inorganic insulating film 7 is formed to a thickness of about 500 nm by a single-layer film or a laminated film of an inorganic insulating film such as silicon nitride, silicon oxide, silicon oxynitride, or the like. Also, as shown in FIGS. 1 and 6, in the second resin layer 8, a concave portion Ca is formed substantially along the trench G so that the inorganic insulating film 7 is exposed from the second resin layer 8 in the frame region F. It is provided in a C shape. Therefore, a concave portion Ca is provided on the surface of the base substrate 10 on the side of the TFT layer 20 along a dam wall W described later. Further, as shown in FIG. 1, the concave portion Ca includes two sides (upper side and lower side in the figure) orthogonal to one side (the right side in the figure) of the frame area in which the terminal portion T is provided, and a frame provided with the terminal section. It is provided continuously on three sides, one side (left side in the figure) opposite to one side (right side in the figure) of the region. Note that, in the present embodiment, the concave portion Ca provided continuously on the side of the frame region is illustrated, but the concave portion Ca may be provided intermittently.

As shown in FIG. 3, the TFT layer 20 includes a base coat film 11 provided on the second resin layer 8 of the base substrate 10, a plurality of first TFTs 9a, a plurality of second TFTs 9b provided on the base coat film 11, and a plurality of And a planarizing film 19a provided on each first TFT 9a, each second TFT 9b, and each capacitor 9c. Here, in the TFT layer 20, as shown in FIG. 2 and FIG. 4, a plurality of gate lines 14 are provided so as to extend in the lateral direction in the drawing and parallel to each other. Further, in the TFT layer 20, as shown in FIGS. 2 and 4, a plurality of source lines 18f are provided so as to extend parallel to each other in the vertical direction in the drawing. Further, in the TFT layer 20, as shown in FIGS. 2 and 4, a plurality of power lines 18g are provided so as to extend in parallel with each other in the vertical direction in the figure. Each power supply line 18g is provided so as to be adjacent to each source line 18f, as shown in FIG. In the TFT layer 20, as shown in FIG. 4, a first TFT 9a, a second TFT 9b, and a capacitor 9c are provided in each sub-pixel P.

The base coat film 11 is composed of, for example, a single-layer film or a laminated film of an inorganic insulating film such as silicon nitride, silicon oxide, or silicon oxynitride.

(4) The first TFT 9a is electrically connected to the corresponding gate line 14 and source line 18f in each sub-pixel P, as shown in FIG. As shown in FIG. 3, the first TFT 9a includes a semiconductor layer 12a, a gate insulating film 13, a gate electrode 14a, a first interlayer insulating film 15, a second interlayer insulating film 17, and a semiconductor layer 12a sequentially provided on the base coat film 11. It has a source electrode 18a and a drain electrode 18b. Here, as shown in FIG. 3, the semiconductor layer 12a is provided in an island shape on the base coat film 11, and has a channel region, a source region, and a drain region. Further, as shown in FIG. 3, the gate insulating film 13 is provided so as to cover the semiconductor layer 12a. Further, as shown in FIG. 3, the gate electrode 14a is provided on the gate insulating film 13 so as to overlap the channel region of the semiconductor layer 12a. Further, as shown in FIG. 3, the first interlayer insulating film 15 and the second interlayer insulating film 17 are provided so as to cover the gate electrode 14a. The source electrode 18a and the drain electrode 18b are provided on the second interlayer insulating film 17 so as to be separated from each other, as shown in FIG. Further, as shown in FIG. 3, the source electrode 18a and the drain electrode 18b are connected via respective contact holes formed in a laminated film of the gate insulating film 13, the first interlayer insulating film 15 and the second interlayer insulating film 17, It is electrically connected to the source region and the drain region of the semiconductor layer 12a, respectively. Note that the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 are each formed of a single-layer film or a stacked film of an inorganic insulating film such as silicon nitride, silicon oxide, or silicon oxynitride. .

As shown in FIG. 4, the second TFT 9b is electrically connected to the corresponding first TFT 9a and the power supply line 18g in each sub-pixel P. As shown in FIG. 3, the first TFT 9b includes a semiconductor layer 12b, a gate insulating film 13, a gate electrode 14b, a first interlayer insulating film 15, a second interlayer insulating film 17, and a semiconductor layer 12b sequentially provided on the base coat film 11. It has a source electrode 18c and a drain electrode 18d. Here, as shown in FIG. 3, the semiconductor layer 12b is provided in an island shape on the base coat film 11, and has a channel region, a source region, and a drain region. Further, as shown in FIG. 3, the gate insulating film 13 is provided so as to cover the semiconductor layer 12b. Further, as shown in FIG. 3, the gate electrode 14b is provided on the gate insulating film 13 so as to overlap the channel region of the semiconductor layer 12b. Further, as shown in FIG. 3, the first interlayer insulating film 15 and the second interlayer insulating film 17 are provided in order to cover the gate electrode 14b. The source electrode 18c and the drain electrode 18d are provided on the second interlayer insulating film 17 so as to be separated from each other, as shown in FIG. Further, as shown in FIG. 3, the source electrode 18c and the drain electrode 18d are connected via respective contact holes formed in a laminated film of the gate insulating film 13, the first interlayer insulating film 15 and the second interlayer insulating film 17, It is electrically connected to the source region and the drain region of the semiconductor layer 12b, respectively.

In the present embodiment, the first gate 9a and the second TFT 9b of the top gate type are illustrated, but the first TFT 9a and the second TFT 9b may be a bottom gate type TFT.

The capacitor 9c is electrically connected to the corresponding first TFT 9a and power supply line 18g in each sub-pixel P, as shown in FIG. Here, as shown in FIG. 3, the capacitor 9c includes a lower conductive layer 14c formed in the same layer with the same material as the gate line 14a and the like, and a first interlayer insulating film provided so as to cover the lower conductive layer 14c. 15 and an upper conductive layer 16 provided on the first interlayer insulating film 15 so as to overlap the lower conductive layer 14c. The upper conductive layer 16 is electrically connected to a power supply line 18g through a contact hole formed in the second interlayer insulating film 17, as shown in FIG.

The flattening film 19a is made of, for example, an organic resin material such as a polyimide resin.

(3) As shown in FIG. 3, the organic EL element 25 includes a plurality of first electrodes 21a, an edge cover 22a, a plurality of organic EL layers 23, and a second electrode 24 sequentially provided on the flattening film 19a.

As shown in FIG. 3, the plurality of first electrodes 21a are provided in a matrix on the planarization film 19a so as to correspond to the plurality of sub-pixels P. Further, as shown in FIG. 3, each first electrode 21a is electrically connected to the drain electrode 18d of each second TFT 9b via a contact hole formed in the planarizing film 19a. Further, the first electrode 21a has a function of injecting holes (holes) into the organic EL layer 23. Further, the first electrode 21a is more preferably formed of a material having a large work function in order to improve the efficiency of hole injection into the organic EL layer 23. Here, as a material forming the first electrode 21a, for example, 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 ( Metal materials such as Ir) and tin (Sn). Further, the material forming the first electrode 21a may be an alloy such as astatine (At) / astatin oxide (AtO ₂ ). Further, the material forming the first electrode 21a is, for example, a conductive oxide such as tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), and indium zinc oxide (IZO). There may be. Further, the first electrode 21a may be formed by laminating a plurality of layers made of the above materials. Note that examples of the compound material having a large work function include indium tin oxide (ITO) and indium zinc oxide (IZO).

(3) As shown in FIG. 3, the edge cover 22a is provided in a lattice shape so as to cover the peripheral portion of each first electrode 21a. Here, examples of a material forming the edge cover 22a include a positive photosensitive resin such as a polyimide resin, an acrylic resin, a polysiloxane resin, and a novolak resin.

(3) The plurality of organic EL layers 23 are arranged on each first electrode 21a as shown in FIG. 3 and are provided in a matrix so as to correspond to the plurality of sub-pixels P. Here, as shown in FIG. 5, each of the organic EL layers 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 which are sequentially provided on the first electrode 21a. It has a layer 5.

The hole injection layer 1 is also called an anode buffer layer, and has a function of making the energy levels of the first electrode 21a and the organic EL layer 23 close to each other and improving the efficiency of hole injection from the first electrode 21a to the organic EL layer 23. Have. Here, as a material constituting the hole injection layer 1, for example, a triazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazoline derivative, a phenylenediamine derivative, an oxazole derivative, a styrylanthracene derivative, a fluorenone derivative, Hydrazone derivatives, stilbene derivatives and the like can be mentioned.

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, as a material constituting the hole transport layer 2, for example, a porphyrin derivative, an aromatic tertiary amine compound, a styrylamine derivative, polyvinyl carbazole, poly-p-phenylene vinylene, polysilane, a triazole derivative, 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, Examples include hydrogenated amorphous silicon carbide, zinc sulfide, and zinc selenide.

In the light emitting layer 3, when a voltage is applied by the first electrode 21a and the second electrode 24, holes and electrons are injected from the first electrode 21a and the second electrode 24, respectively, and the holes and electrons recombine. Area. Here, the light emitting layer 3 is formed of a material having high luminous efficiency. Examples of the material constituting the light emitting layer 3 include a metal oxinoid compound [8-hydroxyquinoline metal complex], a naphthalene derivative, an anthracene derivative, a diphenylethylene derivative, a vinylacetone derivative, a triphenylamine derivative, a butadiene derivative, and a coumarin derivative. , Benzoxazole derivative, oxadiazole derivative, oxazole derivative, benzimidazole derivative, thiadiazole derivative, benzothiazole derivative, styryl derivative, styrylamine derivative, bisstyrylbenzene derivative, tristyrylbenzene derivative, perylene derivative, perinone derivative, aminopyrene derivative, Pyridine derivatives, rhodamine derivatives, aquidin derivatives, phenoxazone, quinacridone derivatives, rubrene, poly-p-phenylene vinylene , Polysilane, and the like.

(4) The electron transport layer 4 has a function of efficiently moving electrons to the light emitting layer 3. Here, as a material constituting the electron transport layer 4, for example, as an organic compound, an oxadiazole derivative, a triazole derivative, a benzoquinone derivative, a naphthoquinone derivative, an anthraquinone derivative, a tetracyanoanthraquinodimethane derivative, a diphenoquinone derivative, or a fluorenone derivative , Silole derivatives, metal oxinoid compounds and the like.

The electron injection layer 5 has a function of making the energy levels of the second electrode 24 and the organic EL layer 23 close to each other and improving the efficiency of injecting electrons from the second electrode 24 into the organic EL layer 23. The drive voltage of the organic EL element 25 can be reduced. Note that the electron injection layer 5 is also called a cathode buffer layer. Here, as a material constituting the electron injection layer 5, for example, lithium fluoride (LiF), magnesium fluoride (MgF ₂ ), calcium fluoride (CaF ₂ ), strontium fluoride (SrF ₂ ), barium fluoride Examples thereof include an inorganic alkali compound such as (BaF ₂ ), aluminum oxide (Al ₂ O ₃ ), and strontium oxide (SrO).

As shown in FIG. 3, the second electrode 24 is provided so as to cover each organic EL layer 23 and the edge cover 22a. The second electrode 24 has a function of injecting electrons into the organic EL layer 23. The second electrode 24 is more preferably made of a material having a small work function in order to improve the efficiency of electron injection into the organic EL layer 23. Here, as a material forming the second electrode 24, for example, 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) , Lithium fluoride (LiF) and the like. The second electrode 24 is made of, for example, magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), sodium (Na) / potassium (K), astatine (At) / astatin oxide (AtO _2). ), Lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), and lithium fluoride (LiF) / calcium (Ca) / aluminum (Al). You may. The second electrode 24 may be formed of a conductive oxide such as tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), and indium zinc oxide (IZO), for example. . Further, the second electrode 24 may be formed by stacking a plurality of layers made of the above materials. Examples of the material having a small work function include magnesium (Mg), lithium (Li), lithium fluoride (LiF), magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), and sodium. (Na) / potassium (K), lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), lithium fluoride (LiF) / calcium (Ca) / aluminum (Al) And the like.

As shown in FIGS. 3, 6, and 7, the sealing film 30 includes a first inorganic insulating film 26 provided to cover the second electrode 24, and an organic film provided on the first inorganic insulating film 26. It has a film 27 and a second inorganic insulating film 28 provided so as to cover the organic film 27, and has a function of protecting the organic EL layer 23 from moisture, oxygen, and the like. Here, the first inorganic insulating film 26 and the second inorganic insulating film 28 are made of, for example, a nitride such as silicon oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), or trisilicon tetranitride (Si ₃ N ₄ ). It is made of an inorganic material such as silicon (SiNx (x is a positive number)) and silicon carbonitride (SiCN). The organic film 27 is made of, for example, an organic material such as an acrylic resin, a polyurea resin, a parylene resin, a polyimide resin, and a polyamide resin.

{Circle around (1)} As shown in FIGS. 1, 6, and 7, the organic EL display device 50 a includes a dam wall W provided in the frame region F so as to surround the display region D.

As shown in FIG. 1, the damming wall W is provided on the display region D side and has a first damming wall Wa provided in a frame shape so as to overlap the peripheral end of the organic film 27 of the sealing film 30. And a second dam wall Wb provided in a frame shape so as to surround the first dam wall Wa. Here, the concave portion Ca formed in the second resin layer 8 described above is provided between the first dam wall Wa and the second dam wall Wb, as shown in FIGS. 1 and 6.

6) As shown in FIGS. 6 and 7, the first dam wall Wa is composed of a resin layer 22c formed of the same material as the edge cover 22a in the same layer.

As shown in FIGS. 6 and 7, the second dam wall Wb is formed on the lower resin layer 19c formed of the same material as the planarizing film 19a in the same layer, and on the lower resin layer 19c (the third conductive layer 21b). And an upper resin layer 22d formed in the same layer with the same material as the edge cover 22a.

In the present embodiment, the configuration in which the distance between the first damming wall Wa and the second damming wall Wb is substantially the same on the four sides of the frame area F is illustrated, but the first damping wall Wa The distance between the second dam wall Wb and the four walls of the frame area F may not be uniform. In other words, the distance Sb (see FIG. 7) between the first damming wall Wa and the second damming wall Wb on one side (right side in FIG. 1) of the frame region F provided with the terminal portion T is determined by the terminal portion T. One of two sides (upper side and lower side in FIG. 1) orthogonal to one side of the provided frame area F and one side (left side in FIG. 1) facing one side of the frame area F in which the terminal portion T is provided. The distance Sa (see FIG. 6) between the first dam wall Wa and the second dam wall Wb on the side may be larger. According to this, at one side of the frame region F where the terminal portion T is provided, the ink that becomes the organic film 27 of the sealing film 30 even if the concave portion Ca is not provided in the second resin layer 8 of the base substrate 10. The amount of damming by the second damming wall Wb can be increased.

{Circle around (1)} As shown in FIGS. 1 and 6, the organic EL display device 50 a includes a first conductive layer 18 h provided in the frame region F outside the trench G in a substantially C shape in plan view. Here, the first conductive layer 18h is electrically connected to a terminal to which a low power supply voltage (ELVSS) is input in the terminal portion T. The first conductive layer 18h is electrically connected to the second electrode 24 via the third conductive layer 21b as shown in FIGS. The first conductive layer 18h is provided so as to cover the concave portion Ca, as shown in FIG. The first conductive layer 18h is formed in the same layer and the same material as the source line 18f. Further, the third conductive layer 21b is formed in the same layer and the same material as the first electrode 21a. Further, TFTs constituting a gate signal control circuit and a light emission control circuit are provided on the display region D side and the first conductive layer 18h side of the upper and lower sides of the trench G in FIG.

{Circle around (1)} As shown in FIGS. 1 and 7, the organic EL display device 50 a includes a second conductive layer 18 i provided in a band shape on one side of the frame region F along the terminal portion T. Here, the second conductive layer 18i is electrically connected to a terminal to which a high power supply voltage (ELVDD) is input in the terminal portion T. Further, as shown in FIGS. 1 and 7, the second conductive layer 18i is provided so as to overlap the first damming wall Wa and the second damming wall Wb, and the first damping wall Wa and the second damming wall are provided. It is provided at least between the walls Wb. The second conductive layer 18i is electrically connected to a plurality of power lines 18g arranged in the display area D. Note that the second conductive layer 18i is formed in the same layer with the same material as the source line 18f and the like.

The organic EL display device 50a is provided in an island shape so as to protrude upward between the display region D and the first dam wall Wa in the frame region F, as shown in FIGS. 3, 6, and 7. And a plurality of peripheral photo spacers 22b. The peripheral photo spacer 22b is formed in the same layer with the same material as the edge cover 22a. The portion protruding above the surface of the edge cover 22a is an island-shaped pixel photo spacer.

Further, as shown in FIG. 7, the organic EL display device 50a is provided on one side of the frame region F along the terminal portion T so as to extend in parallel with each other in a direction orthogonal to the direction in which the bent portion B extends. Of the first wiring 18j. Further, as shown in FIG. 7, the organic EL display device 50a is provided on one side of the frame region F along the terminal portion T so as to extend parallel to each other in a direction orthogonal to the direction in which the bent portion B extends. Is provided. Here, the display area D side of the plurality of first routing wirings 18j is electrically connected to the display wirings (the gate lines 14, the source lines 18f, and the like). As shown in FIG. 7, the terminal portion T side of the plurality of wirings 18j is connected to the plurality of wirings 14j through contact holes formed in the first interlayer insulating film 15 and the second interlayer insulating film 17. It is electrically connected to the display area D side. Further, the terminal portion T side of the plurality of routing wirings 14j is electrically connected to a terminal provided in the terminal portion T. The first routing wiring 18j is formed in the same layer with the same material as the source line 18f and the like. The second routing wiring 14j is formed of the same material as the gate line 14 and the like in the same layer.

In the above-described organic EL display device 50a, in each sub-pixel P, a gate signal is input to the first TFT 9a via the gate line 14, thereby turning on the first TFT 9a, and the gate electrode of the second TFT 9b via the source line 18f. A predetermined voltage corresponding to the source signal is written to the capacitor 14b and the capacitor 9c, and a current from the power supply line 18g defined based on the gate voltage of the second TFT 9b is supplied to the organic EL layer 23. The light emitting layer 3 is configured to emit light to display an image. In the organic EL display device 50a, 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 the light emitting layer 3 emits light until the gate signal of the next frame is input. Will be maintained.

Next, a method for manufacturing the organic EL display device 50a according to the present embodiment will be described. The method for manufacturing the organic EL display device 50a according to the present embodiment includes a TFT layer forming step, an organic EL element forming step, and a sealing film forming step.

<TFT layer forming step>
First, for example, after applying a non-photosensitive polyimide resin on a glass substrate, the first resin layer 6 is formed by performing pre-baking and post-baking on the applied film.

Subsequently, a silicon nitride film, a silicon oxide film, a silicon oxynitride film, or the like is formed on the surface of the substrate on which the first resin layer 6a is formed, for example, by a plasma CVD (chemical vapor deposition) method, thereby forming an inorganic insulating film. A film 7 is formed.

Further, a photosensitive polyimide resin is applied to the surface of the substrate on which the inorganic insulating film 7 has been formed, and then the applied film is subjected to pre-baking, exposure, development, and post-baking to form a second portion having a concave portion Ca. After forming the resin layer 8, the base substrate 10 is formed.

Then, the base coat film 11, the first TFT 9a, the second TFT 9b, the capacitor 9c, and the flattening film 19a are formed on the base substrate 10 by using a known method, and the TFT layer 20 is formed.

<Organic EL element forming step>
The first electrode 21a, the edge cover 22a, the organic EL layer 23 (the hole injection layer 1, the hole transport layer) are formed on the flattening film 19a of the TFT layer 20 formed in the above-described TFT layer forming step by using a known method. The organic EL device 25 is formed by forming the layer 2, the light emitting layer 3, the electron transport layer 4, the electron injection layer 5) and the second electrode 24.

<Sealing film forming step>
First, using a mask, an inorganic insulating film such as a silicon nitride film, a silicon oxide film, or a silicon oxynitride film is formed on the surface of the substrate on which the organic EL device 25 formed in the organic EL device forming step is formed by plasma. The first inorganic insulating film 26 is formed by a CVD method.

Subsequently, an organic resin material such as an acrylic resin is formed on the surface of the substrate on which the first inorganic insulating film 26 is formed, for example, by an ink-jet method to form an organic film 27.

Further, an inorganic insulating film such as a silicon nitride film, a silicon oxide film, a silicon oxynitride film, or the like is formed on the substrate on which the organic film 27 is formed by a plasma CVD method using a mask. The sealing film 30 is formed by forming the inorganic insulating film 28.

Finally, after attaching a protective sheet (not shown) to the surface of the substrate on which the sealing film 30 is formed, the glass substrate is irradiated from the lower surface of the base substrate 10 by irradiating a laser beam from the glass substrate side of the base substrate 10. After peeling, a protective sheet (not shown) is attached to the lower surface of the base substrate 10 from which the glass substrate has been peeled.

有機 As described above, the organic EL display device 50a of the present embodiment can be manufactured.

As described above, according to the organic EL display device 50a of the present embodiment, in the frame region F, the first dam wall Wa and the second dam wall on the surface of the second resin layer 8 of the base substrate 10 on the TFT layer 20 side. A concave portion Ca is provided between the dam walls Wb. Thus, the amount of ink that can be used as the organic film 27 of the sealing film 30 by the second blocking wall Wb can be blocked by the volume of the concave portion Ca, so that the width of the frame region F is suppressed from being increased. The ink blocking effect of the second blocking wall Wb can be enhanced, and the ink that becomes the organic film 27 can be suppressed from climbing over the second blocking wall Wb.

Further, according to the organic EL display device 50a of the present embodiment, since the first conductive layer 18h is provided so as to cover the concave portion Ca in the frame region F, the first conductive layer 18h and the second conductive layer 18 formed by the concave portion Ca are provided. Short circuits between the layers 18i can be suppressed.

<< 2nd Embodiment >>
8 to 11 show a second embodiment of the display device according to the present invention. Here, FIG. 8 is a plan view showing a schematic configuration of the organic EL display device 50b of the present embodiment. FIG. 9 is a cross-sectional view of the frame region F of the organic EL display device 50b along the lines IX-IX and XX in FIGS. FIG. 11 is a plan view showing a schematic configuration of an organic EL display device 50c which is a modification of the organic EL display device 50b. In the following embodiments, the same portions as those in FIGS. 1 to 7 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the first embodiment, the organic EL display device 50a in which the second resin layer 8 of the base substrate 10 is provided with the concave portion Ca having a constant width is illustrated. The organic

EL display devices

50b and 50c in which the concave portions Cb and Cc having different widths are provided in the layer 8 are illustrated.

As shown in FIG. 8, the organic EL display device 50b includes a display area D provided in a substantially rectangular shape with four corners formed in an R shape, and a frame area F provided around the display area D. It has. The organic EL display device 50b includes a base substrate 10, a TFT layer 20 provided on the base substrate 10, and an organic EL element 25 provided on the TFT layer 20, as shown in FIGS. And a sealing film 30 provided so as to cover the organic EL element 25. Further, in the organic EL display device 50b, the concave portion Cb provided in the second resin layer 8 of the base substrate 10 has a width Ha at a portion corresponding to a corner of the display region D as shown in FIGS. The width is formed to be larger than the width Hb in a portion corresponding to the middle part of the side of the display area D. In the present embodiment, the configuration is such that the width Ha of the concave portion Cb in the portion corresponding to the corner of the display region D is formed larger than the width Hb of the concave portion Cb in the portion corresponding to the middle portion of the side of the display region D. As illustrated, the concave portion Cb has a constant width like the concave portion Ca of the first embodiment, and the depth (Va, see FIG. 10) of the portion corresponding to the corner of the display region D is the same as the display region D. It may be formed larger than the depth (Vb, see FIG. 10) in the portion corresponding to the middle part of the side. Further, the concave portion Cb is formed such that the width Ha at a portion corresponding to the corner of the display region D is larger than the width Hb at a portion corresponding to the intermediate portion of the side of the display region D, and then the corner C of the display region D is formed. May be formed to be larger than the depth Vb (see FIG. 10) of the portion corresponding to the middle part of the side of the display area D.

Further, as shown in FIG. 11, the organic EL display device 50c has four corners formed in an R shape, and a middle part of one side (the left side in the figure) bent inward in a C shape in a plan view. The display device includes a display region D provided in a substantially rectangular shape having a notch N, and a frame region F provided around the display region D. The organic EL display device 50c includes a base substrate 10, a TFT layer 20 provided on the base substrate 10, and an organic EL element 25 provided on the TFT layer 20, similarly to the above-described organic EL display device 50b. And a sealing film 30 provided so as to cover the organic EL element 25. In the organic EL display device 50c, the concave portion Cc provided in the second resin layer 8 of the base substrate 10 has a width Ha corresponding to a corner of the display region D as shown in FIG. Is formed to be larger than the width Hb at the portion corresponding to the middle portion between the two sides (upper side and lower side in the figure), and the width Hc at the portion corresponding to the bent portion of one side of the display area D is the display area D (in the figure). The width Hb is formed larger than the width Hb at a portion corresponding to the middle part between the two sides (upper side and lower side). Note that the concave portion Cc is locally larger at the portion corresponding to the corner of the display region D and the bent portion of one side of the display region D instead of the width, similarly to the organic EL display device 50b described above. It may be formed, or may be locally large in width and depth at portions corresponding to the corners of the display region D and the bent portions of one side of the display region D.

The organic

EL display devices

50b and 50c described above have flexibility similarly to the organic EL display device 50a according to the first embodiment, and the organic

EL display devices

50a and 50c are provided in each sub-pixel P via the first TFT 9a and the second TFT 9b. The image display is performed by appropriately emitting light from the light emitting layer 3 of the layer 23.

The organic

EL display devices

50b and 50c of the present embodiment can be manufactured by changing the pattern shape of the second resin layer 8 in the method of manufacturing the organic EL display device 50a described in the first embodiment. it can.

As described above, according to the organic

EL display devices

50b and 50c of the present embodiment, in the frame region F, the first dam wall Wa and the first dam wall Wa on the surface of the second resin layer 8 of the base substrate 10 on the TFT layer 20 side are formed. Depressions Cb and Cc are provided between the second dam walls Wb. Thus, the amount of ink that can be used as the organic film 27 of the sealing film 30 by the second blocking wall Wb can be blocked by the volume of the concave portions Cb and Cc, so that the width of the frame region F is suppressed from expanding. In addition, the effect of blocking the ink by the second blocking wall Wb can be enhanced, and the ink that becomes the organic film 27 can be prevented from climbing over the second blocking wall Wb.

Further, according to the organic

EL display devices

50b and 50c of the present embodiment, the concave portions Cb and Cc are formed such that the width Ha at the portion corresponding to the corner of the display region D corresponds to the middle portion of the side of the display region D. Since the width is larger than the width Hb, it is possible to relatively increase the amount of ink that can be blocked at a portion corresponding to a corner of the display area D. This increases the amount of ink that can be blocked at the portion corresponding to the corner of the display area D where the ink that will become the organic film 27 is likely to accumulate, so that the ink blocking effect by the second blocking wall Wb is effectively achieved. Can be enhanced.

Further, according to the organic EL display device 50c of the present embodiment, the concave portion Cc has a width Hc at a portion corresponding to a bent portion of the display region D and a width Hb at a portion corresponding to an intermediate portion between two sides of the display region D. Therefore, the amount of ink that can be blocked at a portion corresponding to a bent portion of one side of the display area D can be relatively increased. This increases the amount of ink that can be blocked at a portion corresponding to a bent portion of one side of the display region D where the ink that is to be the organic film 27 is likely to accumulate, so that the ink blocking effect by the second blocking wall Wb is provided. Can be effectively increased.

<< Other embodiments >>
In each of the above embodiments, the organic EL layer having a five-layered structure of the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer is exemplified. It may have a three-layer structure of a layer / hole transport layer, a light emitting layer, and an electron transport layer / electron injection layer.

Further, in each of the above embodiments, the organic EL display device in which the first electrode is used as an anode and the second electrode is used as a cathode is exemplified. However, the present invention inverts the stacked structure of the organic EL layer and uses the first electrode as a cathode. It can be applied to an organic EL display device using the second electrode as an anode.

Further, in each of the above embodiments, the organic EL display device in which the electrode of the TFT electrically connected to the first electrode is used as the drain electrode is exemplified. However, the present invention relates to a TFT electrically connected to the first electrode. This electrode can be applied to an organic EL display device called a source electrode.

Further, in each of the above embodiments, the organic EL display device has been described as an example of the display device, but the present invention can be applied to a display device having a plurality of light emitting elements driven by current. For example, the present invention can be applied to a display device including a QLED (Quantum-dot-light-emitting-diode) which is a light-emitting element using a quantum dot-containing layer.

As described above, the present invention is useful for a flexible display device.

Ca, Cb, Cc Concave part D Display area F Frame area T Terminal W Dam wall Wa First dam wall Wb Second dam wall 6 First resin layer 7 Inorganic insulating film 8 Second resin layer 10 Base substrate 18g Power supply Line 18h First conductive layer 18i Second conductive layer 20 TFT layer 21a First electrode 23 Organic EL layer 24 Second electrode 25 Organic EL element (light emitting element)
26 first inorganic insulating film 27 organic film 28 second inorganic insulating film 30 sealing films 50a to 50c organic EL display device

Claims

A base substrate,
A TFT layer provided on the base substrate,
A light-emitting element provided on the TFT layer and constituting a display area;
A sealing film provided so as to cover the light emitting element, in which a first inorganic insulating film, an organic film, and a second inorganic insulating film are sequentially stacked;
A display device including a frame area around the display area and a dam wall provided so as to surround the display area,
A display device, wherein in the frame region, a concave portion is provided on the surface of the base substrate on the TFT layer side along the damming wall.
The display device according to claim 1,
The blocking wall includes a first blocking wall provided on the display area side and overlapping a peripheral end of the organic film, and a second blocking wall provided to surround the first blocking wall. Prepared,
The said recessed part is provided between the said 1st dam wall and the said 2nd dam wall, The display apparatus characterized by the above-mentioned.
The display device according to claim 2,
The frame region is provided in a rectangular frame shape,
A terminal portion is provided on one side of the frame region,
The concave portion is provided on three sides of two sides orthogonal to one side of the frame region provided with the terminal portion and one side opposed to one side of the frame region provided with the terminal portion,
A display device, wherein the concave portion is not provided in an intermediate portion of one side of the frame region where the terminal portion is provided.
The display device according to claim 3,
The display device, wherein the recess is provided continuously.
The display device according to claim 4,
The display device, wherein the width of the concave portion at a portion corresponding to a corner of the display region is larger than the width at a portion corresponding to an intermediate portion of a side of the display region.
The display device according to claim 4 or 5,
The display device, wherein the concave portion has a depth at a portion corresponding to a corner of the display region larger than a depth at a portion corresponding to an intermediate portion of a side of the display region.
The display device according to any one of claims 4 to 6,
An intermediate portion of one side of the display area is provided in a shape bent inward in a plan view,
The display, wherein the recess has a width at a portion corresponding to a bent portion of one side of the display area larger than a width at a portion corresponding to an intermediate portion between the other two sides of the display area. apparatus.
The display device according to any one of claims 3 to 7,
The light emitting element includes a plurality of first electrodes, a light emitting layer, and a second electrode sequentially provided on the TFT layer,
A display device, wherein a first conductive layer electrically connected to the second electrode is provided in the frame region so as to cover the recess.
The display device according to any one of claims 3 to 8,
In the display area, a plurality of power lines are provided so as to extend in parallel with each other,
On one side of the frame region where the terminal portion is provided, a second conductive layer electrically connected to each of the power lines is provided between the first damming wall and the second damming wall. A display device, comprising:
The display device according to any one of claims 3 to 9,
The distance between the first dam wall and the second dam wall on one side of the frame region where the terminal portion is provided is two sides orthogonal to one side of the frame region where the terminal portion is provided. And a distance between the first damming wall and the second damming wall on three sides, that is, one side opposite to one side of the frame region provided with the terminal portion. Display device.
The display device according to any one of claims 1 to 10,
The base substrate is provided with a first resin layer provided on the side opposite to the TFT layer, a second resin layer provided on the TFT layer side, and provided between the first resin layer and the second resin layer. Provided with an inorganic insulating film,
The display device, wherein the recess is provided in the second resin layer such that the inorganic insulating film is exposed from the second resin layer.
The display device according to any one of claims 1 to 11,
The display device, wherein the light-emitting element is an organic EL element.