KR101572264B1 - Organic Light Emitting Display Device and Manufacturing Method of the same - Google Patents

Abstract

Forming a bank on the lower electrode so as to form a transistor on the substrate, forming a lower electrode on the insulating film so as to be connected to a source or a drain of the transistor, and having an opening exposing a part of the lower electrode; Forming a bus electrode on the bank layer; Forming an organic light emitting layer to cover the lower electrode, the bank layer, and the bus electrode, and forming an upper electrode on the organic light emitting layer; Patterning using a laser to expose the bus electrode; And forming a metal electrode so as to cover the region patterned by the laser. The present invention also provides a method of manufacturing an organic light emitting display.

Organic electroluminescent display device, resistance, laser

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic light emitting display device,

The present invention relates to an organic light emitting display and a method of manufacturing the same.

An organic electroluminescent device used in an organic electroluminescent display device is a self-luminous device in which a light emitting layer is formed between two electrodes located on a substrate. The organic light emitting display device may be a top emission type, a bottom emission type or a dual emission type depending on a direction in which light is emitted. The organic light emitting display device is divided into a passive matrix type and an active matrix type according to a driving method.

The subpixel disposed in the organic light emitting display includes an organic light emitting diode including a transistor including a switching transistor, a driving transistor and a capacitor, and a lower electrode connected to the driving transistor included in the transistor portion, an organic light emitting layer, and an upper electrode do. In the organic light emitting display, when a scan signal, a data signal, a power supply, and the like are supplied to a plurality of subpixels arranged in a matrix form, a selected subpixel emits light, thereby displaying an image.

On the other hand, in the conventional organic light emitting display device, the resistance of the electrodes formed in the panel is relatively high. Therefore, in the conventional organic light emitting display device, there is a problem of power consumption increase and luminance unevenness, and thus it is difficult to implement a large area display device.

The present invention for solving the above problems of the background art realizes a large area organic light emitting display device capable of reducing power consumption and improving the display quality by improving the luminance nonuniformity problem.

According to an embodiment of the present invention, a transistor is formed on a substrate, a lower electrode is formed on an insulating film so as to be connected to a source or a drain of the transistor, and a lower electrode is formed on the lower electrode, ; Forming a bus electrode on the bank layer; Forming an organic light emitting layer to cover the lower electrode, the bank layer, and the bus electrode, and forming an upper electrode on the organic light emitting layer; Patterning using a laser to expose the bus electrode; And forming a metal electrode so as to cover the region patterned by the laser. The present invention also provides a method of manufacturing an organic light emitting display.

In the bus electrode forming step, the bus electrode may be formed in a mesh shape or a stripe shape.

The laser patterning step can pattern all the areas where the bus electrodes are located.

The laser patterning step can locally pattern the area where the bus electrode is located.

The laser patterning step can be patterned in the form of a via hole so that the bus electrode is exposed.

The present invention also provides a semiconductor device comprising: a transistor located on a substrate; A lower electrode positioned on the insulating film so as to be connected to a source or a drain of the transistor; A bank layer disposed on the lower electrode and having an opening exposing a portion of the lower electrode; A bus electrode located on the bank layer; An organic light emitting layer positioned to cover the lower electrode, the bank layer, and the bus electrode; An upper electrode positioned on the organic light emitting layer; And a metal electrode located on a region corresponding to the bus electrode and electrically connecting the bus electrode and the upper electrode.

The bus electrode may be formed in a mesh shape or a stripe shape.

The metal electrode can electrically connect the bus electrode and the upper electrode through a via hole formed between the bus electrode and the upper electrode.

The via hole may be formed in a region where the bus electrode is located or may be formed locally.

The area occupied by the metal electrode may be narrower than the area occupied by the bus electrode.

The present invention provides a low resistance electrode structure by patterning a bus electrode positioned under the organic light emitting layer using a laser and connecting the bus electrode and the upper electrode, thereby reducing power consumption, There is an effect of realizing a large area organic light emitting display device capable of improving the display quality by improving the luminance nonuniformity problem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram of an organic light emitting display according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a circuit configuration of the subpixel shown in FIG.

1 and 2, an organic light emitting display according to an exemplary embodiment of the present invention includes a panel (PNL) including sub pixels (SP) arranged in a matrix form, a scan line And a data driver DDRV for supplying a data signal to the data lines DL1... DLn of the sub-pixels SP and the scan driver SDRV for supplying the scan signals to the scan lines SL1, ..., SLm.

The sub-pixel SP may be selected as a passive matrix or an active matrix. The passive matrix type subpixel SP includes an organic light emitting diode located in a crossing region of the scan wiring and the data wiring. The active matrix type sub-pixel SP includes at least one transistor, a capacitor, and an organic light emitting diode which are located at intersections of the scan wiring and the data wiring.

2 shows an active matrix type subpixel SP having a 2T (Transistor) 1C (Capacitor) structure including a switching transistor S, a driving transistor T, a capacitor Cst and an organic light emitting diode D Or a structure in which a transistor or a capacitor is further added.

In the case of the 2T1C structure, the elements included in the subpixel SP can be connected as follows. In the switching transistor S, a gate is connected to a scan line SL1 to which a scan signal is supplied, one end is connected to a data line DL1 to which a data signal is supplied, and the other end is connected to the first node A. The driving transistor T is connected at one end to a first power supply line VDD and a third node C to which a gate is connected to the first node A and a high potential power is supplied, The other end is connected. One end of the capacitor Cst is connected to the first node A and the other end is connected to the second node B. The cathode of the organic light emitting diode D is connected to the second power supply line VSS to which the anode is connected to the third node C and the power supply of the low potential is supplied.

In the above description, the transistors S and T included in the sub-pixel SP are N-type transistors. However, the present invention is not limited thereto. The power supply having a high potential supplied through the first power supply line VDD may be higher than the power supply having a low potential supplied through the second power supply line VSS and the first power supply line VDD and the second power supply line VSS) can be switched according to the driving method.

The above-described subpixel SP can operate as follows. When the scan signal is supplied through the scan line SL1, the switching transistor S is turned on. When the data signal supplied through the data line DL1 is supplied to the first node A through the turned-on switching transistor S, the data signal is stored as a data voltage in the capacitor Cst. When the scan signal is interrupted and the switching transistor S is turned off, the driving transistor T is driven in response to the data voltage stored in the capacitor Cst. The organic light emitting diode D emits light when a high potential power supplied through the first power supply line VDD flows through the second power supply line VSS. However, this is only an example of the driving method, and the embodiment of the present invention is not limited thereto.

An organic light emitting display device according to an embodiment of the present invention can be manufactured by the following method.

3 to 13 are views for explaining a method of manufacturing an organic light emitting display according to an embodiment of the present invention.

As shown in FIGS. 3 and 4, a step of forming a transistor T on a substrate 110 is performed. The transistor T has a top gate type in which the gate is located at the top and a Batam gate type in which the gate is located at the bottom. For convenience of description, the structure of the top gate type transistor will be described as an example in the embodiment.

The transistor T represents a driving transistor included in the sub-pixel. A transistor (T) is formed on the substrate (110). The substrate 110 may be selected to have excellent mechanical strength and dimensional stability as a material for forming the device. As a material of the substrate 110, a glass plate, a metal plate, a ceramic plate, or a plastic plate (polycarbonate resin, acrylic resin, vinyl chloride resin, polyethylene terephthalate resin, polyimide resin, polyester resin, Resin, etc.) and the like. Hereinafter, a method of manufacturing the top gate type transistor will be described.

On the substrate 110, active layers 111a, 111b, and 111c are formed. The active layers 111a, 111b and 111c may comprise amorphous silicon or polycrystalline silicon crystallized therefrom. The active layers 111a, 111b and 111c may include a channel region 111b and a drain region 111c. The source region 111a and the drain region 111c may include a P-type or N-type impurity Can be doped.

A first insulating layer 112 is formed on the active layers 111a, 111b, and 111c. The first insulating layer 112 may be a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or a multilayer thereof, but is not limited thereto.

A gate 113 is formed on the first insulating film 112. The gate 113 may be formed of any one selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper Or an alloy thereof. The gate 113 is formed of a material selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Ne, And may be a multilayer composed of any one selected or an alloy thereof. In addition, the gate 113 may be a double layer of molybdenum / aluminum-neodymium or molybdenum / aluminum.

A second insulating film 114 is formed on the gate 113. The second insulating film 114 may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto.

On the second insulating film 114, a source 115a and a drain 115b are formed. The source 115a and the drain 115b may be formed of a single layer or multiple layers and may be formed of a single layer such as molybdenum (Mo), aluminum (Al), chromium (Cr) And may be made of any one selected from the group consisting of gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) When the source 115a and the drain 115b are multilayered, they may be formed of a triple layer of molybdenum / aluminum-neodymium, molybdenum / aluminum / molybdenum, or molybdenum / aluminum-neodymium / molybdenum.

A third insulating film 116 is formed on the source 115a and the drain 115b. The third insulating film 116 may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto. The third insulating film 116 may be a passivation film.

A pixel electrode 117 connected to the source 115a or the drain 115b is formed on the third insulating film 116. [ The pixel electrode 117 may be formed of a transparent conductive material such as ITO (Indium Tin Oxide), IZO (Indium Tin Oxide), ITZO (Indium Tin Zinc Oxide), or AZO (Al2O3 doped ZnO).

A fourth insulating layer 118 is formed on the third insulating layer 116. The fourth insulating film 118 may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto. The fourth insulating film 118 may be a planarizing film for increasing the flatness of the surface. The above-described transistor is only intended to help understand the embodiment, and the structure of the transistor may be changed depending on the mask process.

Next, as shown in FIG. 5, a step of forming a lower electrode 119 to be connected to the pixel electrode 117 on the fourth insulating film 118 is performed. The lower electrode 119 is connected to the source 115a or the drain 115b of the transistor T through the pixel electrode 117. The lower electrode 119 is connected to the source 115a or 115b of the transistor T, Drain 115b. In the embodiment, the lower electrode 119 may be selected as the anode. The lower electrode 119 selected as the anode may be formed of a transparent conductive material such as ITO (Indium Tin Oxide), IZO (Indium Tin Oxide), ITZO (Indium Tin Zinc Oxide), AZO (Al2O3 doped ZnO) Do not.

Next, a step of forming a bank layer 120 having an opening OPN exposing a part of the lower electrode 119 on the fourth insulating film 118 is performed as shown in FIG. The bank layer 120 may include organic materials such as benzocyclobutene (BCB) resin, acrylic resin or polyimide resin, but is not limited thereto. The light emitting region of the subpixel can be defined by forming an opening OPN exposing a part of the lower electrode 119 when the bank layer 120 is formed.

Next, a step of forming the bus electrode 121 on the bank layer 120 is performed as shown in FIG. The bus electrode 121 is formed of the same or different material as the lower electrode 119. The bus electrode 121 is formed of at least one material selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Ne, Layer structure or a multi-layer structure. 8 and 9, the bus electrode 121 may be formed in a mesh shape (FIG. 8) or a stripe shape (FIG. 9), but is not limited thereto. Although not shown, when the bus electrode 121 is formed on the bank layer 120, a pattern is formed so that a part of the bank layer 120 is recessed, and then a bus electrode 121 is formed inside the depressed portion It is possible. In this case, the thickness of the bus electrode 121 can be made thicker, and the ease of implementation of the low resistance of the electrode can be increased.

Next, the organic light emitting layer 122 is formed to cover the lower electrode 119, the bank layer 120, and the bus electrode 121 as shown in FIG. The organic light emitting layer 122 is formed to cover the lower electrode 119, the bank layer 120, and the bus electrode 121 formed on the substrate 110. 11, the organic light emitting layer 122 may include a hole injection layer 122a, a hole transport layer 122b, a light emitting layer 122c, an electron transport layer 122d, and an electron injection layer 122e. The hole injection layer 122a may function to smooth the injection of holes and may be formed of a material such as cupper phthalocyanine, PEDOT (poly (3,4) -ethylenedioxythiophene), PANI (polyaniline) and NPD (N, -N, N'-diphenyl benzidine), but the present invention is not limited thereto. The hole transport layer 122b serves to smooth the transport of holes, and the hole transport layer 122b may be formed of a material such as NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, , N'-bis- (phenyl) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-tris (N-3-methylphenyl-N-phenylamino) The light emitting layer 122c may include a material that emits red, green, blue, and white light, and may be formed using a phosphorescent material or a fluorescent material. The light emitting layer 122c may include, In the case of emitting red light, a host material containing CBP (carbazole biphenyl) or mCP (1,3-bis (carbazol-9-yl)), PIQIr (acac) (bis (1-phenylisoquinoline) acetylacetonate iridium) A dopant containing at least one selected from the group consisting of PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) (DBM) 3 (Phen) or perylene. Alternatively, when the light emitting layer 122c emits green light, the light emitting layer 122c may be formed of CBP or mPCP and may comprise a phosphorescent material comprising a dopant material comprising Ir (ppy) 3 (fac tris (2-phenylpyridine) iridium), alternatively Alq3 (tris (8-hydroxyquinolino ) aluminum, but it is not limited thereto. When the light emitting layer 122c emits blue light, it includes a host material including CBP or mCP, and includes (4,6-F2ppy) 2Irpic Lt; RTI ID = 0.0 > a < / RTI > dopant material. Alternatively, the fluorescent material may include any one selected from the group consisting of spiro-DPVBi, spiro-6P, distyrylbenzene (DSB), distyrylarylene (DSA), PFO polymer, and PPV polymer. It is not limited. The electron transporting layer 122d serves to smooth the transport of electrons and may be made of any one or more selected from the group consisting of Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq and SAlq But are not limited thereto. The electron injecting layer 122 e may function to facilitate the injection of electrons and may be made of Alq 3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq or SAlq. Here, the present invention is not limited thereto, and at least one of the hole injecting layer 122a, the hole transporting layer 122b, the electron transporting layer 122d and the electron injecting layer 122e may be omitted.

Next, a step of forming the upper electrode 123 on the organic light emitting layer 122 is performed as shown in FIG. The upper electrode 123 may be selected as a cathode. The upper electrode 123 selected as the cathode may be a single layer or multiple layers using a single material such as aluminum (Al), aluminum nitride (AlNd) and silver (Ag) ) / Silver (Ag), or the like, using a plurality of materials.

Next, as shown in FIG. 12, a step of patterning using the laser L is performed so that the bus electrode 121 is exposed. When the bus electrode 121 is patterned to be exposed, it is patterned by a welding method using a laser (L). The upper electrode 123 and the organic light emitting layer 122 are removed and the bus electrode 121 is exposed by using the laser L. Various structures for exposing the bus electrode 121 in a pattern can be selected . For example, it is possible to pattern all of the areas where the bus electrodes 121 are located or to locally pattern the areas where the bus electrodes 121 are located.

Next, a step of forming the metal electrode 124 to cover the region patterned by the laser L as shown in Fig. 13 is performed. The metal electrode 124 is formed so that the bus electrode 121 is patterned to expose the bus electrode 121 by the laser L and the bus electrode 121 and the upper electrode 123 are electrically connected to each other. When forming the metal electrode 124, a point deposition method for depositing only a specific region, a silk screen method, a method using a mask, or the like can be used, but the present invention is not limited thereto.

The resistance of the upper electrode 123 can be lowered by forming the metal electrode 124 to expose the bus electrode 121 and electrically connect the upper electrode 123 and the bus electrode 121 as in the embodiment. The higher the resistance of the electrode, the more the power consumption is increased. The increase of the power consumption can be explained by the increase of the sheet resistance and the increase of the current loss due to the voltage drop of the power supply wiring (IR drop). The lower power consumption of the large area organic light emitting display device can be reduced by lowering the resistance of the upper electrode 123 which causes the increase of the resistance and the luminance unevenness phenomenon can be prevented by using various structures of the metal electrode 124 It is possible to suppress as much as possible.

Hereinafter, the shape of the metal electrode 124 according to the structure for exposing the bus electrode 121 will be described with reference to FIGS. 14 to 21. FIG.

14 to 21 are views showing various shapes of the metal electrode.

14 and 15, the bus electrode 121 is formed in a mesh or stripe shape, and the metal electrode 124 is formed to be positioned in a specific region of the bus electrode 121. In this case, a pattern is formed so that only a part of the bus electrode 121 is locally exposed in the laser (L) patterning step so that the patterned area is formed into a circular via hole shape. The metal electrode 124 electrically connects the bus electrode 121 and the upper electrode 123 through a circular via hole formed between the bus electrode 121 and the upper electrode 123.

16 and 17, the bus electrode 121 is formed in a mesh or stripe shape, and the metal electrode 124 is formed to be positioned in a specific region of the bus electrode 121. In this case, patterning is performed so that only a part of the bus electrode 121 is locally exposed in the laser (L) patterning step so that the patterned area is formed into a rectangular via hole. The metal electrode 124 electrically connects the bus electrode 121 and the upper electrode 123 through a rectangular via hole formed between the bus electrode 121 and the upper electrode 123.

18 and 19, the bus electrode 121 is formed in a mesh or stripe shape, and the metal electrode 124 is formed in a specific area of the bus electrode 121. In this case, a pattern is formed by locally exposing a part of the bus electrode 121 in the laser (L) patterning step so that the patterned region is formed into a rectangular and circular via hole. The metal electrode 124 electrically connects the bus electrode 121 and the upper electrode 123 through a square and circular via hole formed between the bus electrode 121 and the upper electrode 123.

20 and 21, the bus electrode 121 is formed in a mesh or stripe shape, and the metal electrode 124 is formed to be located in all areas of the bus electrode 121. In this case, patterned regions are formed so as to have the same shape as that of the bus electrodes 121, so that all the regions of the bus electrodes 121 are exposed in the laser (L) patterning step. The metal electrode 124 electrically connects the bus electrode 121 and the upper electrode 123 through a via hole formed between the bus electrode 121 and the upper electrode 123. In this structure, unlike the above method, a pattern is applied so that only a part of the bus electrode 121 is locally exposed in the laser (L) patterning step, and the metal electrode 124 corresponding to all areas of the bus electrode 121 . Accordingly, the metal electrode 124 is formed in correspondence with all the regions of the bus electrode 121 in such a manner that only a part of the metal electrode 124 is in contact with the bus electrode 121.

14 to 19, the metal electrode 124 is formed in a point shape in a specific area so as to occupy a narrower area than the area occupied by the bus electrode 121 and to reduce the resistance of the corresponding area. The structure in which the metal electrode 124 is formed in the point shape as described above can be applied when a region in which the resistance is high in the display panel and a region in which the luminance is unevenly locally occur.

20 and 21, the metal electrode 124 occupies an area substantially corresponding to the area occupied by the bus electrode 121, and is formed in the same area as the shape of the bus electrode 121 in all areas so as to reduce the resistance of the entire area. . The structure in which the metal electrode 124 is formed so as to cover all the areas of the bus electrode 121 can be applied when the resistance of the entire display panel is lowered and the brightness of all the areas is expressed uniformly.

As described above, the present invention provides a low resistance electrode structure by patterning a bus electrode located under the organic light emitting layer using a laser and connecting the bus electrode and the upper electrode, thereby reducing power consumption, There is an effect of realizing a large area organic light emitting display device capable of improving the display quality by improving the luminance nonuniformity problem.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is to be understood, therefore, that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

1 is a schematic block diagram of an organic light emitting display according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating an exemplary circuit configuration of the subpixel shown in FIG. 1; FIG.

3 to 13 are views for explaining a method of manufacturing an organic light emitting display according to an embodiment of the present invention.

Figs. 14 to 21 are diagrams showing various shapes of metal electrodes. Fig.

DESCRIPTION OF THE REFERENCE NUMERALS

110: substrate 112: first insulating film

113: gate 114: second insulating film

116: third insulating film 117: pixel electrode

118: fourth insulating film 119: lower electrode

120: bank layer 121: bus electrode

122: organic light emitting layer 123: upper electrode

124: metal electrode

Claims (10)

Forming a transistor on the substrate, forming a lower electrode on the insulating film so as to be connected to a source or a drain of the transistor, and forming a bank layer on the lower electrode so as to have an opening exposing a part of the lower electrode; Forming a bus electrode on the bank layer; Forming an organic light emitting layer to cover the lower electrode, the bank layer, and the bus electrode, and forming an upper electrode on the organic light emitting layer; Patterning using a laser so that the bus electrode is exposed; And And forming a metal electrode to cover the patterned region by the laser. The method according to claim 1, In the bus electrode forming step, Wherein the bus electrodes are formed in a mesh shape or a stripe shape. The method according to claim 1, Wherein the laser patterning step comprises: And patterning all the regions where the bus electrodes are located. The method according to claim 1, Wherein the laser patterning step comprises: Wherein a region where the bus electrode is located is locally patterned. The method according to claim 1, Wherein the laser patterning step comprises: Wherein the bus electrode is patterned in a via hole pattern to expose the bus electrode. A transistor located on a substrate; A lower electrode positioned on the insulating film so as to be connected to a source or a drain of the transistor; A bank layer disposed on the lower electrode and having an opening exposing a part of the lower electrode; A bus electrode located on the bank layer; An organic light emitting layer positioned to cover the lower electrode, the bank layer, and the bus electrode; An upper electrode positioned on the organic light emitting layer; And And a metal electrode located on a region corresponding to the bus electrode and electrically connecting the bus electrode and the upper electrode. The method according to claim 6, Wherein the bus electrode is formed in a mesh shape or a stripe shape. The method according to claim 6, The metal electrode And the bus electrode and the upper electrode are electrically connected to each other through a via hole formed between the bus electrode and the upper electrode. 9. The method of claim 8, The via- Wherein the bus electrode is formed in a region where the bus electrode is located or is locally formed. The method according to claim 6, The area occupied by the metal electrode is, And the bus electrode is narrower than the area occupied by the bus electrode.

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