Patent Application
20230255076
The present invention relates to a display device.
In recent years, light-emitting organic electroluminescence (EL) display devices using organic EL elements are drawing attention as a replacement for liquid crystal display devices. Here, in order to reduce deterioration of the organic EL elements caused by such contaminants as water and oxygen, a sealing structure is suggested for the organic EL display devices. In the sealing structure, a sealing film to cover the organic EL elements is made of a multilayer film including an inorganic film and an organic film.
For example, Patent Document 1 discloses a display device including a thin-film sealing layer to cover organic light-emitting elements. The thin-film sealing layer has a multilayer structure in which an inorganic film layer formed by such a technique as chemical vapor deposition (CVD) and an organic film layer formed by such a technique as ink-jet printing are alternately arranged.
As seen in the display device disclosed in Patent Document 1 above, if the organic film of the sealing film is formed by ink-jet printing, a dam wall has to be provided to a frame region around a display region including the organic EL elements, in order to block ink that forms the organic film. Moreover, the organic EL display device includes, for example, a resin substrate, a thin-film-transistor (hereinafter also referred to as “TFT”) layer provided on the resin substrate, and an organic-EL-element layer provided on the TFT layer. Here, the TFT layer includes a frame wire provided to the frame region, and a planarization film having a flat surface in the display region and provided on the frame wire. Moreover, the organic-EL-element layer includes, for example, a plurality of first electrodes, an edge cover, a plurality of organic EL layers, and a second electrode, all of which are provided above the planarization film on top of another in the stated order. Then, if the dam wall is formed of the same material as, and in the same layer as, the planarization film is, a developer to be used for forming the planarization film, an etchant to be used for forming the first electrodes, and a developer to be used for forming the edge cover cause damage to the frame wire. Thus, for example, an end portion of the frame wire in cross-section is inevitably shaped into a peak. The peak reduces sealing capability of the sealing film to be formed on the frame wire, which might cause deterioration of the organic EL elements.
In view of the above problems, the present invention is intended to reduce damage to a frame wire during a production step of the frame wire.
In order to achieve the above object, a display device according to the present invention includes: a base substrate; a thin-film-transistor layer provided on the base substrate, and including a first wiring layer, a first planarization film, a second wiring layer, and a second planarization film, all of which are stacked on top of another in a stated order; a light-emitting-element layer provided on the thin-film-transistor layer, and including a plurality of first electrodes, an edge cover, a plurality of light-emitting layers, and a second electrode, all of which are stacked on top of another in a stated order, each of the plurality of first electrodes and each of the plurality of light-emitting layers corresponding to one of a plurality of sub-pixels included in a display region, and the edge cover and the second electrode being provided in common among the plurality of sub-pixels; a sealing film provided to cover the light-emitting-element layer, and including a first inorganic sealing film, an organic sealing film, and a second inorganic sealing film, all of which are stacked on top of another in a stated order; a first dam wall provided in a frame region around the display region and surrounding the display region, the first dam wall being shaped into a frame to overlap with a peripheral end portion of the organic sealing film; a power supply line provided in the display region and serving as the second wiring layer; a first frame wire provided in the frame region and serving as the first wiring layer, the first frame wire extending to a terminal unit at an end portion of the frame region and being electrically connected to the power supply line; and a second frame wire provided in the frame region and serving as the first wiring layer, the second frame wire extending to the terminal unit and being electrically connected to the second electrode through a conductive layer formed of a same material as, and in a same layer as, each of the first electrodes is. The first planarization film and the second planarization film include a first slit shaped into a frame, provided between the display region and the first dam wall, and penetrating the first planarization film and the second planarization film. In the first slit, the first frame wire and the second frame wire have respective edge portions facing each other and covered with a protective film made of an inorganic insulating film included in the thin-film transistor layer.
The present invention can reduce damage to a frame wire during a production step of the frame wire.
Described below in derail are embodiments of the present invention, with reference to the drawings. Note that the present invention shall not be limited to the embodiments below.
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The resin substrate layer 10 is made of, for example, polyimide resin.
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The TFT layer 30a in
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The base coat film 11 is, for example, a monolayer inorganic insulating film made of such a material as silicon nitride, silicon oxide, or silicon oxide nitride. Alternatively, the base coat film 11 is a multilayer inorganic insulating film made of these materials.
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Note that, in this embodiment, the first TFTs 9a, the second TFTs 9b, and the third TFTs 9c are top gate TFTs. Alternatively, the first TFTs 9a, the second TFTs 9b, and the third TFTs 9c may be bottom gate TFTs.
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The first planarization film 22a and the second planarization film 28a, and an edge cover 32a to be described later, are made of, for example, such an organic resin material as polyimide resin, acrylic resin, or novolak resin.
The organic-EL-element layer 35 includes a plurality of organic EL elements arranged in a matrix. As illustrated in
The plurality of first electrodes 31a illustrated in
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The hole injection layer 1, also referred to as an anode buffer layer, is capable of approximating the energy levels of the first electrode 31a and the organic EL layer 33 and increasing efficiency in injection of the holes from the first electrode 31a to the organic EL layer 33. Here, exemplary materials of the hole injection layer 1 may include 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, a hydrazone derivative, and a stilbene derivative.
The hole-transport layer 2 is capable of improving efficiency in transporting the holes from the first electrode 31a to the organic EL layer 33. Here, exemplary materials of the hole transport-layer 2 may include a porphyrin derivative, an aromatic tertiary amine compound, a styryl amine derivative, polyvinylcarbazole, poly-p-phenylene vinylene, polysilane, a triazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazoline derivative, a pyrazolone derivative, a phenylenediamine derivative, an arylamine derivative, an amine-substituted chalcone derivative, an oxazole derivative, a styrylanthracene derivative, a fluorenone derivative, a hydrazone derivative, a stilbene derivative, hydrogenated amorphous silicon, hydrogenated amorphous silicon carbide, zinc sulfide, and zinc selenide.
The light-emitting layer 3 is a region into which the holes and the electrons are injected from the first electrode 31a and the second electrode 24 and recombine with each other, when a voltage is applied by the first electrode 31a and the second electrode 34. Here, the light-emitting layer 3 is formed of a material with high light emission efficiency. Exemplary materials of the light-emitting layer 3 may include a metal oxinoid compound [an 8-hydroxyquinoline metal complex], a naphthalene derivative, an anthracene derivative, a diphenylethylene derivative, a vinylacetone derivative, a triphenylamine derivative, a butadiene derivative, a coumarin derivative, a benzoxazole derivative, an oxadiazole derivative, an oxazole derivative, a benzimidazole derivative, a thiadiazole derivative, a benzothiazole derivative, a styryl derivative, a styrylamine derivative, a bisstyrylbenzene derivative, a trisstyrylbenzene derivative, a perylene derivative, a perinone derivative, an aminopyrene derivative, a pyridine derivative, a rodamine derivative, an acridine derivative, phenoxazone, a quinacridone derivative, rubrene, poly-p-phenylene vinylene, and polysilane.
The electron-transport layer 4 is capable of efficiently transporting the electrons to the light-emitting layer 3. Here, exemplary materials of the electron-transport layer 4 may include, as organic compounds, an oxadiazole derivative, a triazole derivative, a benzoquinone derivative, a naphthoquinone derivative, an anthraquinone derivative, a tetracyanoanthraquinodimethane derivative, a diphenoquinone derivative, a fluorenone derivative, a silole derivative, and a metal oxinoid compound.
The electron-injection layer 5 is capable of approximating the energy levels of the second electrode 34 and the organic EL layer 33, and increasing efficiency in injection of the electrons from the second electrode 34 to the organic EL layer 33. Such a feature makes it possible to decrease a drive voltage of each of the organic EL elements included in the organic-EL-element layer 35. Note that the electron-injection layer 5 may also be referred to as a cathode buffer layer. Here, exemplary materials of the electron-injection layer 5 may include: such inorganic alkaline compounds as lithium fluoride (LiF), magnesium fluoride (MgF2), calcium fluoride (CaF2), strontium fluoride (SrF2), and barium fluoride (BaF2); aluminum oxide (Al2O3); and strontium oxide (SrO).
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The above organic EL display device 50a displays an image as follows: In each sub-pixel P, a gate signal is input through the gate line 14d to the first TFT 9a. The first TFT 9a turns ON. Through the source line 21f, a predetermined voltage corresponding a source signal is written in the gate electrode 14b of the second TFT 9b and the capacitor 9d. Through the light-emission control line 14e, a light-emission control signal is input into the third TFT 9c. Then, the third TFT 9c turns ON. In accordance with a gate voltage of the second TFT 9b, a current is supplied from the power supply line 27a to the organic EL layer 33. The supplied current allows the light-emitting layer 3 of the organic EL layer 33 to emit light and display the image. Note that, in the organic EL display device 50a, even if the first TFT 9a turns OFF, the gate voltage of the second TFT 9b is held in the capacitor 9d. Hence, the light-emitting layer 3 keeps emitting light until a gate signal of the next frame is input.
Described next is a method for producing the organic EL display device 50 of this embodiment. Note that the method for producing the organic EL display device 50a of this embodiment includes: a TFT layer forming step; an organic-EL-element layer forming step; and a sealing film forming step.
TFT Layer Forming Step
First, for example, on the resin substrate layer 10 formed on a glass substrate, an inorganic insulating film (a thickness of approximately 1000 nm) such as a silicon oxide film is deposited by, for example, plasma chemical vapor deposition (CVD) to form the base coat film 11.
Then, throughout the substrate on which the base coat film 11 is formed, for example, an amorphous silicon film (a thickness of approximately 50 nm) is deposited by the plasma CVD. The amorphous silicon film is crystalized by a technique such as laser annealing to form a semiconductor film of a polysilicon film. After that, the semiconductor film is patterned to form a layer such as the semiconductor layer 12a.
After that, throughout the substrate on which a layer such as the semiconductor layer 12a is formed, an inorganic insulating film (approximately 100 nm) such as an silicon oxide film is deposited by, for example, the plasma CVD to form the gate insulating film 13 to cover a layer such as the semiconductor layer 12a.
Moreover, throughout the substrate on which the gate insulating film 13 is formed, films such as an aluminum film (a thickness of approximately 350 nm) and a molybdenum nitride film (a thickness of approximately 50 nm) are sequentially deposited by, for example, sputtering. After that, the metal multilayer film of these metals is patterned to form the first electrode layer including the gate lines 14d.
Then, using lines such as the gate lines 14d as a mask, a layer such as the semiconductor layer 12a is doped with impurity ions and provided with a channel region, a source region, and a drain region.
After that, throughout the substrate including a layer such as the semiconductor layer 12a provided with the channel region, the source region, and the drain region, an inorganic insulating film (a thickness of approximately 100 nm) such as an silicon oxide film is deposited by, for example, the plasma CVD to form the first interlayer insulating film 15.
Then, throughout the substrate on which the first interlayer insulating film 15 is formed, films such as an aluminum film (a thickness of approximately 350 nm) and a molybdenum nitride film (a thickness of approximately 50 nm) are sequentially deposited by, for example, sputtering. After that, the metal multilayer film of these metals is patterned to form the second electrode layer including the upper wiring layer 16a.
Moreover, throughout the substrate on which the second electrode layer is formed, an inorganic insulating film (a thickness of approximately 500 nm) such as a silicon oxide film is deposited by, for example, the plasma CVD to form the second interlayer insulating film 17.
After that, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 are patterned, so that contact holes are formed in these films.
Then, throughout the substrate in which the contact holes are formed, films such as a titanium film (a thickness of approximately 30 nm), an aluminum film (a thickness of approximately 300 nm), and a titanium film (a thickness of approximately 50 nm) are sequentially deposited by, for example, sputtering. After that, the metal multilayer film of these metals is patterned to form the first wiring layer including the source lines 21f.
Furthermore, throughout the substrate on which the first wiring layer is formed, a polyimide-based photosensitive resin film (a thickness of approximately 2 μm) is applied by, for example, spin-coating or slit-coating. The applied film is prebaked, exposed to light, developed, and postbaked to form the first planarization film 22a made of an organic insulating film.
After that, throughout the substrate on which the first planarization film 22a is formed, an inorganic insulating film (a thickness of approximately 500 nm) such as a silicon oxide film is deposited by, for example, the plasma CVD. The inorganic insulating film is patterned to form the protective film 23a.
Then, throughout the substrate on which the protective film 23a is formed, films such as a titanium film (a thickness of approximately 30 nm), an aluminum film (a thickness of approximately 300 nm), and a titanium film (a thickness of approximately 50 nm) are sequentially deposited by, for example, sputtering. After that, the metal multilayer film of these metals is patterned to form the second wiring layer including the power supply line 27a.
Finally, throughout the substrate on which the second wiring layer is formed, a polyimide-based photosensitive resin film (a thickness of approximately 2 μm) is applied by, for example, spin-coating or slit-coating. The applied film is prebaked, exposed to light, developed, and postbaked to form the second planarization resin film 28a made of an organic insulating film.
Through the above steps, the TFT layer 30a can be formed.
Organic-EL-Element Layer Forming Step
On the second planarization film 28a of the TFT layer 30a formed at the TFT layer forming step, the first electrodes 31a, the edge cover 32a, the organic EL layers 33 (each including the hole-injection layer 1, the hole-transport layer 2, the organic light-emitting layer 3, the electron-transport layer 4, and the electron-injection layer 5), and the second electrode 34 are formed by a known technique to form the organic-EL-element layer 35.
Sealing Film Forming Step
First, on the surface of the substrate on which the organic-EL-element layer 35 is formed at the organic-EL-element-layer forming step, an inorganic insulating film such as, for example, a silicon nitride film, a silicon oxide film, or a silicon nitride oxide film is deposited by the plasma CVD to form the first inorganic sealing film 36, using a mask.
Next, on the surface of the substrate on which the first inorganic film 36 is formed, an organic resin material such as acrylic resin is applied by, for example, ink-jet printing to form the organic sealing film 37.
After that, on the substrate on which the organic film 37 is formed, an inorganic insulating film such as, for example, a silicon nitride film, a silicon oxide film, or a silicon nitride oxide film is deposited by the plasma CVD to form the second inorganic film 38, using a mask. Hence, the second inorganic sealing film 38 is formed. Thus, the sealing film 40 is formed.
Finally, on the surface of the substrate on which the sealing film 40 is formed, a not-shown protective sheet is attached. After that, a laser beam is emitted on the glass substrate of the resin substrate layer 10 to remove the glass substrate from the bottom surface of the resin substrate layer 10. Furthermore, on the bottom surface of the resin substrate layer 10 from which the glass substrate removed, a not-shown protective sheet is attached.
Through the above steps, the organic EL display device 50a of this embodiment can be produced.
As described above, as to the organic EL display device 50a of this embodiment, the TFT layer 30a includes: the first electrode layer including the gate lines 14d; the first interlayer insulating film 15; the second electrode layer including the upper wiring layer 16a; the second interlayer insulating film 17; the first wiring layer including the source lines 21f; the first planarization film 22a; the protective film 23a; the second wiring layer including the power supply line 27a; and the second planarization film 28a, all of which are stacked on top of another in the stated order. Here, in the frame region F around the display region D, the first frame wire 21h is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21h is electrically connected to the power supply line 27a toward the display region D. Moreover, in the frame region F, the second frame wire 21i is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21i is electrically connected, through the conductive layer 31b, to the second electrode 34 toward the display region D. Furthermore, the first planarization film 22a and the second planarization film 28a include the first slit Sa shaped into a frame, provided between the display region D and the first dam wall Wa, and penetrating the first planarization film 22a and the second planarization film 28a. The first dam wall Wa overlaps with the peripheral end portion of the organic sealing film 37. In addition, around the first dam wall Wa, the second dam wall Wb is provided in the shape of a frame. Moreover, the second planarization film 28a includes the second slit Sb shaped into a frame, provided between the first dam wall Wa and the second dam wall Wb, and penetrating the second planarization film 28a. Then, in the first slit Sa and the second slit Sb, the first frame wire 21h and the second frame wire 21i have respective edge portions facing each other and covered with the protective film 23a. Hence, even if the first slit Sa and the second slit Sb are formed, the first dam wall Wa and the second dam wall Wb keep the first frame wire 21h and the second frame wire 21i from damage caused by side-etching with a developer to be used for forming the first planarization film 22a and the second planarization film 28a, an etchant to be used for forming the first electrodes 31a, and a developer to be used for forming the edge cover 32a. Such a feature can reduce the damage to the first frame wire 21h and the second frame wire 21i during the production steps of these wires. Moreover, the damage to the first frame wire 21h and the second frame wire 21i is reduced during the production steps of these wires, thereby making it possible to ensure sealing capability of the sealing film 40 formed above the first frame wire 21h and the second frame wire 21i. Such features can reduce deterioration of the organic EL layers 33, thereby contributing to improvement in reliability of the organic EL display device 50a.
Moreover, as to the organic EL display device 50a of this embodiment, the first dam wall Wa includes the first metal protruding portion 27c, and the second dam wall Wb includes the second metal protruding portion 27d. Thanks to such a feature, the first dam wall Wa and the second dam wall Wb are formed tall, and can block ink that forms the organic sealing film 37.
Furthermore, as to the organic EL display device 50a of this embodiment, the trench G, which is shaped into a frame and penetrates the first planarization film 22a and the second planarization film 28a, is provided around the display region D. Such a feature can keep water from moving to the display region D through the inside of such resin layers as the first planarization film 22a and the second planarization film 28a. As a result, the organic EL layers 33 can be kept from deterioration.
In addition, as to the organic EL display device 50a of this embodiment, the first metal protruding portion 27c and the second metal protruding portion 27d are provided to electrically connect to either the first frame wire 21h or the second frame wire 21i. Such a feature can reduce wiring resistance of the first frame wire 21h and the second frame wire 21i.
Moreover, as to the organic EL display device 50a of this embodiment, the first metal layer 27e is provided to electrically connect to the second frame wire 21i. Such a feature can reduce wiring resistance of the second frame wire 21i.
Furthermore, as to the organic EL display device 50a of this embodiment, the terminal metal layer 27f is provided to electrically connect to the first frame wire 21h. Such a feature can reduce wiring resistance of the first frame wire 21h.
In addition, as to the organic EL display device 50a of this embodiment, the surface of the first planarization film 22a is covered with the protective film 23a. Such a feature can keep the surface layer of the first planarization film 22a from being etched when, for example, the second wiring layer including the power supply line 27a is patterned by dry etching. As a result, the interior of the chamber of a dry etching apparatus can be kept from contamination.
The above first embodiment exemplifies the organic EL display device 50a including the second wiring layer made of a metal multilayer film having three layers. Whereas, this embodiment exemplifies the organic EL display device 50b including a second wiring layer made of a metal multilayer film having two layers.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50b includes: the display region D; and the frame region F provided around the display region D. Moreover, as illustrated in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30b illustrated in
The TFT layer 30b illustrated in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30b includes the plurality of gate lines 14d in the display region D extending in parallel with one another. Moreover, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30b includes the plurality of light-emission control lines 14e in the display region D extending in parallel with one another. Furthermore, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30b includes the plurality of source lines 21f in the display region D extending in parallel with one another. In addition, the TFT layer 30b includes the power supply line 27ab in display region D provided in a grid form and serving as the second wiring layer. Note that, as illustrated in
In addition, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50b also includes the first frame wire 21h and the second frame wire 21i in the frame region F.
Moreover, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50b includes the first dam wall Wa and the second dam wall Wb in the frame region F.
As illustrated in
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In addition, as illustrated in
Moreover, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50b includes a terminal metal layer 27fb in the frame region F. The terminal metal layer 27fb is equivalent to the terminal metal layer 27f of the organic EL display device 50a. Here, as illustrated in
Moreover, as illustrated in
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50b is flexible, and allows, in each of the sub pixels P, the light-emitting layer 3 of the organic EL layer 33 to appropriately emit light through the first TFT 9a, the second TFT 9b, and the third TFT 9c to display an image.
The organic EL display device 50b of this embodiment can be produced as follows: at the TFT layer forming step of a method for producing the organic EL display device 50a of the above first embodiment, the metal multilayer film for forming the second wiring layer is changed from a three-layer film (a titanium film (upper)/an aluminum film (intermediate)/a titanium film (lower)) to a two-layer film (an aluminum film (upper)/a titanium film (lower)). Here, when the two-layer (an aluminum film (upper)/a titanium film (lower)) metal multilayer film is patterned, a resist pattern is formed on the metal multilayer film. Using the resist pattern, the metal multilayer is wet-etched. Here, as to an end portion of the second wiring layer, a line width of the aluminum film (upper) is smaller than a line width of the titanium film (lower) because of a difference in etching rate. As illustrated in
As described above, as to the organic EL display device 50b of this embodiment, the TFT layer 30b includes: the first electrode layer including the gate lines 14d; the first interlayer insulating film 15; the second electrode layer including the upper wiring layer 16a; the second interlayer insulating film 17; the first wiring layer including the source lines 21f; the first planarization film 22a; the protective film 23a; the second wiring layer including the power supply line 27ab; and the second planarization film 28a, all of which are stacked on top of another in the stated order. Here, in the frame region F around the display region D, the first frame wire 21h is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21h is electrically connected to the power supply line 27ab toward the display region D. Moreover, in the frame region F, the second frame wire 21i is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21i is electrically connected, through the conductive layer 31b, to the second electrode 34 toward the display region D. Furthermore, the first planarization film 22a and the second planarization film 28a include the first slit Sa shaped into a frame, provided between the display region D and the first dam wall Wa, and penetrating the first planarization film 22a and the second planarization film 28a. The first dam wall Wa overlaps with the peripheral end portion of the organic sealing film 37. In addition, around the first dam wall Wa, the second dam wall Wb is provided in the shape of a frame. Moreover, the second planarization film 28a includes the second slit Sb shaped into a frame, provided between the first dam wall Wa and the second dam wall Wb, and penetrating the second planarization film 28a. Then, in the first slit Sa and the second slit Sb, the first frame wire 21h and the second frame wire 21i have respective edge portions facing each other and covered with the protective film 23a. Hence, even if the first slit Sa and the second slit Sb are formed, the first dam wall Wa and the second dam wall Wb keep the first frame wire 21h and the second frame wire 21i from damage caused by side-etching with a developer to be used for forming the first planarization film 22a and the second planarization film 28a, an etchant to be used for forming the first electrodes 31a, and a developer to be used for forming the edge cover 32a. Such a feature can reduce the damage to the first frame wire 21h and the second frame wire 21i during the production steps of these wires. Moreover, the damage to the first frame wire 21h and the second frame wire 21i is reduced during the production steps of these wires, thereby making it possible to ensure sealing capability of the sealing film 40 formed above the first frame wire 21h and the second frame wire 2ii. Such features can reduce deterioration of the organic EL layers 33, thereby contributing to improvement in reliability of the organic EL display device 50b.
Moreover, as to the organic EL display device 50b of this embodiment, the first dam wall Wa includes the first metal protruding portion 27cb, and the second dam wall Wb includes the second metal protruding portion 27db. Thanks to such a feature, the first dam wall Wa and the second dam wall Wb are formed tall, and can block ink that forms the organic sealing film 37.
Furthermore, as to the organic EL display device 50b of this embodiment, the trench G, which is shaped into a frame and penetrates the first planarization film 22a and the second planarization film 28a, is provided around the display region D. Such a feature can keep water from moving to the display region D through the inside of such resin layers as the first planarization film 22a and the second planarization film 28a. As a result, the organic EL layers 33 can be kept from deterioration.
In addition, as to the organic EL display device 50b of this embodiment, the first metal protruding portion 27cb and the second metal protruding portion 27db are provided to electrically connect to either the first frame wire 21h or the second frame wire 21i. Such a feature can reduce wiring resistance of the first frame wire 21h and the second frame wire 21i.
Moreover, as to the organic EL display device 50b of this embodiment, the first metal layer 27eb is provided to electrically connect to the second frame wire 21i. Such a feature can reduce wiring resistance of the second frame wire 21i.
Furthermore, as to the organic EL display device 50b of this embodiment, the terminal metal layer 27fb is provided to electrically connect to the first frame wire 21h. Such a feature can reduce wiring resistance of the first frame wire 21h.
In addition, as to the organic EL display device 50b of this embodiment, the surface of the first planarization film 22a is covered with the protective film 23a. Such a feature can keep the surface layer of the first planarization film 22a from being etched when, for example, the second wiring layer including the power supply line 27a is patterned by dry etching. As a result, the interior of the chamber of a dry etching apparatus can be kept from contamination.
The above first embodiment exemplifies the organic EL display device 50a including the protective film 23a provided between the first planarization film 22a and the second wiring layer. Whereas, this embodiment exemplifies the organic EL display device 50c including a protective film 23b provided between the first wiring layer and the first planarization film 22a.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c includes: the display region D; and the frame region F provided around the display region D. Moreover, as illustrated in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30c illustrated in
The TFT layer 30c illustrated in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30c includes the plurality of gate lines 14d in the display region D extending in parallel with one another. Moreover, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30c includes the plurality of light-emission control lines 14e in the display region D extending in parallel with one another. Furthermore, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30c includes the plurality of source lines 21f in the display region D extending in parallel with one another. In addition, the TFT layer 30c includes the power supply line 27a in display region D provided in a grid form and serving as the second wiring layer. Moreover, in the TFT layer 30c, similar to the TFT layer 30a of the above first embodiment, each of the sub-pixels P includes a first TFT 9a, a second TFT 9b, a third TFT 9c, and a capacitor 9d. Moreover, in the TFT layer 30c, the drain electrode 21d of the third TFT 9c illustrated in
In addition, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c also includes the first frame wire 21h and the second frame wire 21i in the frame region F.
Moreover, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c illustrated in
Furthermore, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c, as illustrated in
In addition, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c includes the terminal metal layer 27f in the frame region F. The terminal metal layer 27f is shaped into a substantial T-shape, and serves as the second wiring layer. Here, as illustrated in
Moreover, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c, as illustrated in
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50c is flexible, and allows, in each of the sub-pixels P, the light-emitting layer 3 of the organic EL layer 33 to appropriately emit light through the first TFT 9a, the second TFT 9b, and the third TFT 9c to display an image.
The organic EL display device 50c of this embodiment can be produced as follows: at the TFT layer forming step of a method for producing the organic EL display device 50a in the above embodiment, a step of forming the protective film 23a is carried out between a step of forming the first wiring layer and a step of forming the first planarization film 22a.
As described above, as to the organic EL display device 50c of this embodiment, the TFT layer 30c includes: the first electrode layer including the gate lines 14d; the first interlayer insulating film 15; the second electrode layer including the upper wiring layer 16a; the second interlayer insulating film 17; the first wiring layer including the source lines 21f; the protective film 23b; the first planarization film 22a; the second wiring layer including the power supply line 27a; and the second planarization film 28a, all of which are stacked on top of another in the stated order. Here, in the frame region F around the display region D, the first frame wire 21h is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21h is electrically connected to the power supply line 27a toward the display region D. Moreover, in the frame region F, the second frame wire 21i is provided to extend to the terminal unit T to serve as the first wiring layer. The first frame wire 21i is electrically connected, through the conductive layer 31b, to the second electrode 34 toward the display region D. Furthermore, the first planarization film 22a and the second planarization film 28a include the first slit Sa shaped into a frame, provided between the display region D and the first dam wall Wa, and penetrating the first planarization film 22a and the second planarization film 28a. The first dam wall Wa overlaps with the peripheral end portion of the organic sealing film 37. In addition, around the first dam wall Wa, the second dam wall Wb is provided in the shape of a frame. Moreover, the second planarization film 28a includes the second slit Sb shaped into a frame, provided between the first dam wall Wa and the second dam wall Wb, and penetrating the second planarization film 28a. Then, in the first slit Sa and the second slit Sb, the first frame wire 21h and the second frame wire 21i have respective edge portions facing each other and covered with the protective film 23b. Hence, even if the first slit Sa and the second slit Sb are formed, the first dam wall Wa and the second dam wall Wb keep the first frame wire 21h and the second frame wire 21i from damage caused by side-etching with a developer to be used for forming the first planarization film 22a and the second planarization film 28a, an etchant to be used for forming the first electrodes 31a, and a developer to be used for forming the edge cover 32a. Such a feature can reduce the damage to the first frame wire 21h and the second frame wire 21i during the production steps of these wires. Moreover, the damage to the first frame wire 21h and the second frame wire 21i is reduced during the production steps of these wires, thereby making it possible to ensure sealing capability of the sealing film 40 formed above the first frame wire 21h and the second frame wire 21i. Such features can reduce deterioration of the organic EL layers 33, thereby contributing to improvement in reliability of the organic EL display device 50c.
Furthermore, as to the organic EL display device 50c of this embodiment, the first dam wall Wa includes the first metal protruding portion 27c, and the second dam wall Wb includes the second metal protruding portion 27d. Thanks to such a feature, the first dam wall Wa and the second dam wall Wb are formed tall, and can block ink that forms the organic sealing film 37.
In addition, as to the organic EL display device 50c of this embodiment, the trench G, which is shaped into a frame and penetrates the first planarization film 22a and the second planarization film 28a, is provided around the display region D. Such a feature can keep water from moving to the display region D through the inside of such resin layers as the first planarization film 22a and the second planarization film 28a. As a result, the organic EL layers 33 can be kept from deterioration.
Moreover, as to the organic EL display device 50c of this embodiment, the first metal protruding portion 27c and the second metal protruding portion 27d are provided to electrically connect to either the first frame wire 21h or the second frame wire 21i. Such a feature can reduce wiring resistance of the first frame wire 21h and the second frame wire 21i.
Furthermore, as to the organic EL display device 50c of this embodiment, the first metal layer 27e is provided to electrically connect to the second frame wire 21i. Such a feature can reduce wiring resistance of the second frame wire 21i.
In addition, as to the organic EL display device 50c of this embodiment, the terminal metal layer 27f is provided to electrically connect to the first frame wire 21h. Such a feature can reduce wiring resistance of the first frame wire 21h.
The above first embodiment exemplifies the organic EL display device 50a including the protective film 23a provided between the first planarization film 22a and the second wiring layer. Whereas, this embodiment exemplifies the organic EL display device 50d including: the protective film 23b provided between the first wiring layer and the first planarization film 22a; and the second wiring layer made of a multilayer film having two layers.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50d includes: the display region D; and the frame region F provided around the display region D. Moreover, as illustrated in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30d illustrated in
The TFT layer 30d in
Similar to the TFT layer 30a of the above first embodiment, the TFT layer 30d includes the plurality of gate lines 14d in the display region D extending in parallel with one another. Moreover, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30d includes the plurality of light-emission control lines 14e in the display region D extending in parallel with one another. Furthermore, similar to the TFT layer 30a of the above first embodiment, the TFT layer 30d includes the plurality of source lines 21f in the display region D extending in parallel with one another. In addition, the TFT layer 30d includes the power supply line 27ab in display region D provided in a grid form and serving as the second wiring layer. Moreover, in the TFT layer 30d, similar to the TFT layer 30a of the above first embodiment, each of the sub-pixels P includes a first TFT 9a, a second TFT 9b, a third TFT 9c, and a capacitor 9d. Furthermore, in the TFT layer 30d, the second TFT 9b in each sub-pixel P is electrically connected to the corresponding first TFT 9a, power supply line 27ab, and third TFT 9c. In addition, in the TFT layer 30d, the third TFT 9c in each sub-pixel P is electrically connected to the corresponding second TFT 9a, power supply line 27ab, and light-emission control line 14e. Moreover, in the TFT layer 30d, the drain electrode 21d of the third TFT 9c illustrated in
In addition, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50d also includes the first frame wire 21h and the second frame wire 21i in the frame region F.
Moreover, similar to the organic EL display device 50b of the above second embodiment, the organic EL display device 50d illustrated in
Furthermore, similar to the organic EL display device 50b of the above second embodiment, the organic EL display device 50d includes, as illustrated in
In addition, similar to the organic EL display device 50b of the above second embodiment, the organic EL display device 50d includes the terminal metal layer 27fb in the frame region F. The terminal metal layer 27fb serves as the second wiring layer. Here, as illustrated in
Moreover, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50d, as illustrated in
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50d is flexible, and allows, in each of the sub-pixels P, the light-emitting layer 3 of the organic EL layer 33 to appropriately emit light through the first TFT 9a, the second TFT 9b, and the third TFT 9c to display an image.
The organic EL display device 50d of this embodiment can be produced as follows: at the TFT layer forming step of a method for producing the organic EL display device 50a of the above first embodiment, the metal multilayer film for forming the second wiring layer is changed from a three-layer film (a titanium film (upper)/an aluminum film (intermediate)/a titanium film (lower)) to a two-layer film (an aluminum film (upper)/a titanium film (lower)) as seen in the above second embodiment, and a step of forming the protective film 23a is carried out between a step of forming the first wiring layer and a step of forming the first planarization film 22a
As described above, as to the organic EL display device 50d of this embodiment, the TFT layer 30d includes: the first electrode layer including the gate lines 14d; the first interlayer insulating film 15; the second electrode layer including the upper wiring layer 16a; the second interlayer insulating film 17; the first wiring layer including the source lines 21f; the protective film 23b; the first planarization film 22a; the second wiring layer including the power supply line 27ab; and the second planarization film 28a, all of which are stacked on top of another in the stated order. Here, in the frame region F around the display region D, the first frame wire 21h is provided to extend to the terminal unit T and to serve as the first wiring layer. The first frame wire 21h is electrically connected to the power supply line 27ab toward the display region D. Moreover, in the frame region F, the second frame wire 21i is provided to extend to the terminal unit T and to serve as the first wiring layer. The first frame wire 21i is electrically connected, through the conductive layer 31b, to the second electrode 34 toward the display region D. Furthermore, the first planarization film 22a and the second planarization film 28a include the first slit Sa shaped into a frame, provided between the display region D and the first dam wall Wa, and penetrating the first planarization film 22a and the second planarization film 28a. The first dam wall Wa overlaps with the peripheral end portion of the organic sealing film 37. In addition, around the first dam wall Wa, the second dam wall Wb is provided in the shape of a frame. Moreover, the second planarization film 28a includes the second slit Sb shaped into a frame, provided between the first dam wall Wa and the second dam wall Wb, and penetrating the second planarization film 28a. Then, in each of the first slit Sa and the second slit Sb, the first frame wire 21h and the second frame wire 21i have respective edge portions facing each other and covered with the protective film 23b. Hence, even if the first slit Sa and the second slit Sb are formed, the first dam wall Wa and the second dam wall Wb keep the first frame wire 21h and the second frame wire 21i from damage caused by side-etching with a developer to be used for forming the first planarization film 22a and the second planarization film 28a, an etchant to be used for forming the first electrodes 31a, and a developer to be used for forming the edge cover 32a. Such a feature can reduce the damage to the first frame wire 21h and the second frame wire 21i during the production steps of these wires. Moreover, the damage to the first frame wire 21h and the second frame wire 21i is reduced during the production steps of these wires, thereby making it possible to ensure sealing capability of the sealing film 40 formed above the first frame wire 21h and the second frame wire 21i. Such features can reduce deterioration of the organic EL layers 33, thereby contributing to improvement in reliability of the organic EL display device 50d.
Furthermore, as to the organic EL display device 50d of this embodiment, the first dam wall Wa includes the first metal protruding portion 27cb, and the second dam wall Wb includes the second metal protruding portion 27db. Thanks to such a feature, the first dam wall Wa and the second dam wall Wb are formed tall, and can block ink that forms the organic sealing film 37.
In addition, as to the organic EL display device 50d of this embodiment, the trench G, which is shaped into a frame and penetrates the first planarization film 22a and the second planarization film 28a, is provided around the display region D. Such a feature can keep water from moving to the display region D through the inside of such resin layers as the first planarization film 22a and the second planarization film 28a. As a result, the organic EL layers 33 can be kept from deterioration.
Moreover, as to the organic EL display device 50d of this embodiment, the first metal protruding portion 27cb and the second metal protruding portion 27db are provided to electrically connect to either the first frame wire 21h or the second frame wire 21i. Such a feature can reduce wiring resistance of the first frame wire 21h and the second frame wire 21i.
Furthermore, as to the organic EL display device 50d of this embodiment, the first metal layer 27eb is provided to electrically connect to the second frame wire 21i. Such a feature can reduce wiring resistance of the second frame wire 21i.
In addition, as to the organic EL display device 50d of this embodiment, the terminal metal layer 27fb is provided to electrically connect to the first frame wire 21h. Such a feature can reduce wiring resistance of the first frame wire 21h.
Moreover, as to the organic EL display device 50d of this embodiment, the terminal metal layer 27fb includes: the lower metal film 24fb made of a titanium film and provided toward the resin substrate layer 10; and the upper metal film 25fb made of an aluminum film and provided toward the organic-EL-element layer 35. Here, the terminal metal layer 27fb has an end portion shaped into a forward tapered shape so that the lower metal film 24fb protrudes further than the upper metal film 25fb. The end portion is covered with the second planarization film 28a. Such a feature improves contact between the end portion of the terminal metal layer 27fb and the second planarization film 28a. The improved contact can block intrusion of, for example, water into the display region D through a path; that is, an interface between the end portion of the terminal metal layer 27fb and the second planarization film 28a, thereby contributing to improvement in reliability of the organic EL display device 50d.
The above first embodiment exemplifies the organic EL display device 50a in which: the first metal protruding portion 27c having a relatively narrow width, the second metal protruding portion 27d, and the terminal metal layer 27f are electrically connected to the first frame wire 21h; and the first metal protruding portion 27c having a relatively narrow width, the second metal protruding portion 27d, and the first metal layer 27e are electrically connected to the fecund frame wire 21i. Whereas, this embodiment exemplifies the organic EL display device 50f in which: a second metal layer 27h having a relatively wide width is electrically connected to the first frame wire 21h; and a third metal layer 27i having a relatively wide width is electrically connected to the second frame wire 21i.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50f includes: the display region D; and the frame region F provided around the display region D. Moreover, similar to the organic EL display device 50b of the above second embodiment, the organic EL display device 50f includes: the resin substrate layer 10; the TFT layer 30b provided on the resin substrate layer 10; the organic-EL-element layer 35 provided on the TFT layer 30b; and the sealing film 40 provided to cover the organic-EL-element layer 35.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50f also includes the first frame wire 21h and the second frame wire 21i in the frame region F. Here, as illustrated in
Furthermore, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50f includes the first dam wall Wa and the second dam wall Wb in the frame region F.
In addition, similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50f includes the plurality of peripheral photo spacers 32b in the frame region F. The plurality of peripheral photo spacers 32b are shaped into islands, and protrude upwards at opposing edge portions of the trench G.
Similar to the organic EL display device 50a of the above first embodiment, the organic EL display device 50f is flexible, and allows, in each of the sub-pixels P, the light-emitting layer 3 of the organic EL layer 33 to appropriately emit light through the first TFT 9a, the second TFT 9b, and the third TFT 9c to display an image.
The organic EL display device 50f of this embodiment can be produced as follows: at the TFT layer forming step of a method for producing the organic EL display device 50a of the above first embodiment, the metal multilayer film for forming the second wiring layer is changed from a three-layer film (a titanium film (upper)/an aluminum film (intermediate)/a titanium film (lower)) to a two-layer film (an aluminum film (upper)/a titanium film (lower)), and patterned in a different shape.
As described above, as to the organic EL display device 50f of this embodiment, the TFT layer 30b includes: the first electrode layer including the gate lines 14d; the first interlayer insulating film 15; the second electrode layer including the upper wiring layer 16a; the second interlayer insulating film 17; the first wiring layer including the source lines 21f; the first planarization film 22a; the protective film 23a; the second wiring layer including the power supply line 27ab; and the second planarization film 28a, all of which are stacked on top of another in the stated order. Here, in the frame region F around the display region D, the first frame wire 21h is provided to extend to the terminal unit T and to serve as the first wiring layer. The first frame wire 21h is electrically connected to the power supply line 27ab toward the display region D. Moreover, in the frame region F, the second frame wire 21i is provided to extend to the terminal unit T and to serve as the first wiring layer. The first frame wire 21i is electrically connected, through the conductive layer 31b, to the second electrode 34 toward the display region D. Furthermore, the first planarization film 22a and the second planarization film 28a include the first slit Sa shaped into a frame, provided between the display region D and the first dam wall Wa, and penetrating the first planarization film 22a and the second planarization film 28a. The first dam wall Wa overlaps with the peripheral end portion of the organic sealing film 37. In addition, around the first dam wall Wa, the second dam wall Wb is provided in the shape of a frame. Moreover, the second planarization film 28a includes the second slit Sb shaped into a frame, provided between the first dam wall Wa and the second dam wall Wb, and penetrating the second planarization film 28a. Then, in the first slit Sa and the second slit Sb, the first frame wire 21h and the second frame wire 21i have respective edge portions facing each other and covered with the protective film 23a. Hence, even if the first slit Sa and the second slit Sb are formed, the first dam wall Wa and the second dam wall Wb keep the first frame wire 21h and the second frame wire 21i from damage caused by side-etching with a developer to be used for forming the first planarization film 22a and the second planarization film 28a, an etchant to be used for forming the first electrodes 31a, and a developer to be used for forming the edge cover 32a. Such a feature can reduce the damage to the first frame wire 21h and the second frame wire 21i during the production steps of these wires. Furthermore, the second metal layer 27h and the third metal layer 27i include: the lower metal films 24h and 24i made of titanium films and provided toward the resin substrate layer 10; and the upper metal films 25h and 251 made of aluminum films and provided toward the organic-EL-element layer 35. Hence, because of the developer to be used for forming the second planarization film 28a, the etchant to be used for forming the first electrodes 31a, and the developer to be used for forming the edge cover 32a, the end portions of the second metal layer 27h and the third metal layer 27i are each shaped into a forward tapered shape so that, in each of the end portions of the second metal layer 27h and the third metal layer 27i, the lower metal film protrudes further than the upper metal film. Such a feature makes it possible to ensure sealing capability of the sealing film 40 formed above the second metal layer 27h and the third metal layer 27i. This sealing capability can reduce deterioration of the organic EL layers 33, thereby contributing to improvement in reliability of the organic EL display device 50f.
In addition, as to the organic EL display device 50f of this embodiment, the trench G, which is shaped into a frame and penetrates the first planarization film 22a and the second planarization film 28a, is provided around the display region D. Such a feature can keep water from moving to the display region D through the inside of such resin layers as the first planarization film 22a and the second planarization film 28a. As a result, the organic EL layers 33 can be kept from deterioration.
Moreover, as to the organic EL display device 50f of this embodiment, the third metal layer 27h and the fourth metal layer 27i, each having a wide width, are provided to electrically and respectively connect to the first frame wire 21h and the second frame wire 21i. Such a feature can further reduce wiring resistance of the first frame wire 21h and the second frame wire 21i.
Furthermore, as to the organic EL display device 50f of this embodiment, the surface of the first planarization film 22a is covered with the protective film 23a. Such a feature can keep the surface layer of the first planarization film 22a from being etched when, for example, the second wiring layer including the power supply line 27ab is patterned by dry etching. As a result, the interior of the chamber of a dry etching apparatus can be kept from contamination.
In the above embodiments, each organic EL layer is formed of a multilayer including such five layers as the hole-injection layer, the hole-transport layer, the light-emitting layer, the electron-transport layer, and the electron-injection layer. Alternatively, the organic EL layer may be formed of a multilayer including such three layers as a hole-injection and hole-transport layer, the light-emitting layer, and an electron-transport and electron-injection layer.
Moreover, in the organic EL display devices of the above embodiments described as examples, the first electrodes are anodes and the second electrode is a cathode. Alternatively, the present invention is applicable to an organic EL display device whose multilayered structure is inverted so that the first electrodes are cathodes and the second electrode is an anode.
Furthermore, in the organic EL display devices of the above embodiments described as examples, the electrodes of the TFTs connected to the first electrodes are drain electrodes. Alternatively, the present invention is applicable to an organic EL display device in which the electrodes of the TFTs connected to the first electrodes are referred to as source electrodes.
In addition, the display devices of the embodiments described as examples are organic EL display devices. Alternatively, the present invention is applicable to a display device including a plurality of light-emitting elements driven by a current. For example, the present invention is applicable to a display device including quantum-dot light emitting diodes (QLEDs); that is, light-emitting elements using layers containing quantum dots.
As can be seen, the present invention is applicable to a flexible display device.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/028122 | 7/20/2020 | WO |
