KR20100112779A - Organic light emitting display device - Google Patents

Abstract

PURPOSE: An organic electroluminescent display device is provided to improve the transmittance of a non-element region by forming a data wiring of a single layer using transparent metal. CONSTITUTION: A display unit(AA) comprises a plurality of sub pixels(P). A plurality of sub pixels are positioned on a substrate(110) in a matrix and are driven with a driving unit on the substrate. The driving unit generates a scan signal and a data signal in response to various signals supplied from the outside and includes a scan driving unit which supplies the scan signal to a plurality of sub pixels and a data driving unit which supplies the data signal.

Description

[0001] The present invention relates to an organic light emitting display device,

An embodiment of the present invention relates to an organic light emitting display.

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.

In addition, the organic light emitting display device may include a top emission type, a bottom emission type, or a dual emission type depending on a direction in which light is emitted. It is divided into a passive matrix and an active matrix depending on the driving method.

A subpixel disposed in an active matrix organic light emitting display device includes a transistor including a switching transistor, a driving transistor and a capacitor, an organic light emitting portion including a lower electrode connected to the driving transistor included in the transistor portion, .

In the organic light emitting display device, 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, the selected subpixel emits light to display an image.

An embodiment of the present invention is to provide an organic electroluminescent display device in which objects located on the rear surface of a panel are displayed on a front surface of a panel to increase the utilization.

An embodiment of the present invention includes a subpixel which is located on a substrate and includes a device region in which a light emitting portion is located and a non-device region in which a light emitting portion is not located, and the non-device region is 30% to 75% The organic electroluminescent display device according to claim 1,

On the other hand, in another aspect, an embodiment of the present invention includes a sub-pixel including a device region in which an element including a transistor portion and a light emitting portion is located and a non-element region in which a device is not located, And the device area occupies 30% to 75% of the device area.

The element region can be defined by an aperture region that defines the light emitting region of the subpixel.

The size of the non-device region may be proportional to the size of the sub-pixel region.

The upper electrode included in the light emitting portion may be connected to a positive power supply line that is located along the element region of the subpixel and supplies positive power.

The negative power supply wiring for supplying the negative power to the subpixel can be wired so as to be in parallel with the scanning wiring located in the element region.

The subpixel includes a bank layer defining an opening region, and the negative power supply wiring may be located inside the opening region defined by the bank layer.

At least one of the data wiring connected to the subpixel, the scan wiring, and the negative power supply wiring may be formed in a three-layer laminated structure including the first transparent electrode, the silver and the second transparent electrode.

At least one of the data wiring connected to the subpixel, the scan wiring, and the negative power supply wiring may be formed as a two-layer cap structure including a transparent electrode covering the metal electrode.

The data line located in the non-device region can be transparent.

An embodiment of the present invention has an effect of providing an organic electroluminescent display device in which the object located on the rear surface of the panel is reflected on the front surface of the panel to enhance the utilization.

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

1 is a schematic diagram of an organic light emitting display device.

As shown in FIG. 1, the organic light emitting display device may include a display unit AA on which a plurality of subpixels P are arranged in a matrix form. The substrate 110 is formed of a material having high permeability. As the material of the substrate 110, glass, metal, ceramic or plastic (polycarbonate resin, acrylic resin, vinyl chloride resin, polyethylene terephthalate resin, polyimide resin, polyester resin, epoxy resin, silicone resin, And the like, but the present invention is not limited thereto.

Since the plurality of sub pixels P located on the substrate 110 are vulnerable to moisture or oxygen, the sealing substrate 190 having good permeability is provided and the adhesive member SL is provided on the outer substrate 110 of the display portion AA, So that the substrate 110 and the sealing substrate 190 can be sealed. Alternatively, the sealing substrate 110 may be sealed with a material having good permeability, such as a film or a protective film.

The organic light emitting display may be classified into a passive matrix type and an active matrix type. In the case of the passive matrix type, the subpixel includes an element region where the light emitting portion is located and a non-element region where the light emitting portion is not located. In the case of the active matrix type, the subpixel includes an element region in which an element including the transistor portion and the light emitting portion is located, and a non-element region in which the element is not located. Since the passive matrix type has a simple structure including only the light emitting portion, a description thereof will be omitted and the following description will be made in more detail with reference to the active matrix type.

On the other hand, a plurality of sub-pixels P located in the display unit AA can be driven by a driving unit DRV located on the substrate 110 to display an image. The driving unit DRV can generate a scan signal, a data signal, and the like corresponding to various signals supplied from the outside, and can supply the generated signals to the display unit AA.

The driving unit DRV may include a scan driver for supplying the scan signals to the plurality of subpixels P and a data driver for supplying the data signals to the plurality of subpixels P. [ Here, the driving unit DRV schematically illustrates a case where the scan driver and the data driver are formed on one chip, and the scan driver and the data driver may be separately disposed outside the substrate 110 or the substrate 110 have.

Hereinafter, the subpixels located in the display portion AA will be described in more detail.

FIG. 2 is a plan view of a subpixel according to an exemplary embodiment of the present invention, and FIG. 3 is a view illustrating a size of a non-device region.

Referring to FIG. 2, a subpixel according to an embodiment includes an element region DA defined in a subpixel region PA and a non-element region NA. In the case of the active matrix type subpixel, an element including the transistor portion and the light emitting portion is located in the element region DA, the element is not located in the non-element region NA, and the element region DA It accounts for% ~ 75%.

When the non-element area NA defined in the sub pixel area PA occupies 30% or more of the element area DA, it is possible to secure a transparent area such that an object located on the rear surface of the panel is reflected on the front surface of the panel do. When the non-element area NA defined in the sub-pixel area PA occupies 75% or less of the element area DA, it is possible to increase the ratio of the object placed on the rear surface of the panel to the front area of the panel, It is possible to prevent the image displayed on the panel from being distorted when the subpixel emits light and to display the image.

Referring to FIG. 3, (a) shows a subpixel with a number of pixels per inch of 105 ppi (240 * 80), (b) shows a subpixel with a number of pixels per inch of 117 ppi (216 * 72) (D) shows a subpixel with 166 ppi (153 * 53) pixels per inch, (e) shows a subpixel with 181 ppi (141 * 47) pixels per inch, Subpixel. As shown, the size of the non-device area NA in the embodiment may be proportional to the size of the sub-pixel area PA.

The size of the non-device area NA can be increased up to 75% when the size of the sub-pixel area PA is large and the size of the non-device area NA is reduced to 30% As shown in FIG. The reason why the size of the non-device area NA is proportional to the size of the sub pixel area PA is that the size of the device formed in the device area DA is kept constant, It can be adjusted.

Table 1 below shows data on the transmittance of the non-element region (NA) according to the number of pixels per inch of the subpixels shown in FIG. 3 when the element of the subpixel has a 2T (transistor) 1C (capacitor) structure.

Number of pixels per inch (ppi) Sub-pixel area (탆 ² ) Element area (탆 ² ) Permeability (%) 105 ppi 19200 4644 75 117 ppi 15552 4644 75 128 ppi 13068 4644 64 166 ppi 8109 4644 43 181 ppi 6627 4644 30

Hereinafter, the circuit structure and the structure of a sub-pixel having a 2T1C structure will be described.

4 is a circuit diagram of a sub-pixel having a 2T1C structure.

Referring to FIG. 4, a sub-pixel having a 2T1C structure includes a switching transistor S1, a driving transistor T1, a capacitor Cst, and a light emitting portion D. In the switching transistor S1, a gate is connected to the scan line SCAN, a first electrode is connected to the data line DATA, and a second electrode is connected to the first node A. The driving transistor T1 has a gate connected to the first node A, a first electrode connected to the second node B, and a second electrode connected to the negative power supply line GND. The first electrode of the capacitor Cst is connected to the first node A and the second electrode of the capacitor Cst is connected to the negative power supply line GND. In the light emitting portion D, the anode is connected to the positive power supply line VDD and the cathode is connected to the second node B.

The driving of the sub-pixel having the 2T1C structure as described above will be schematically described as follows. When the scan signal and the data signal are supplied to the scan line SCAN and the data line DATA, the switching transistor S1 is turned on and the data voltage is stored in the capacitor Cst. Then, when the switching transistor S1 is turned off, the driving transistor T1 is driven by the data voltage stored in the capacitor Cst so that the light emitting portion D emits light.

FIGS. 5 to 22 are process cross-sectional views for fabricating the subpixel shown in FIG.

As shown in FIG. 5, a buffer layer 111 is formed on a substrate 110. The buffer layer 111 may be formed to protect a thin film transistor formed in a subsequent process from an impurity such as an alkali ion or the like flowing out from the substrate 110, but may be omitted. On the buffer layer 111, a semiconductor layer 112a is formed. A semiconductor layer (112a) may form an a-Si, poly-Si or SiO _2, but not limited to these. However, in this embodiment, the semiconductor layer 112a is formed of a-Si.

As shown in FIGS. 6 and 7, the semiconductor layer 112a is subjected to Alternating Magnetic Field Crystallization (AMFC). And an impurity layer 113 is formed on the crystallized semiconductor layer 112b. The impurity layer 113 may be formed by doping with n +, but is not limited thereto. An ohmic contact layer 114 is formed on the impurity layer 113. [ The ohmic contact layer 114 may be formed of a metal such as molybdenum (Mo), but is not limited thereto.

8, a photoresist PR is formed on the ohmic contact layer 114 and the region of the photoresist PR corresponding to the region where the channel is to be formed by diffraction exposure is patterned as "H1" do.

As shown in FIG. 9, the photoresist PR is ashed to expose the ohmic contact layer 114, such as "H2 ".

Etching is performed from the ohmic contact layer 114 to the semiconductor layer 112b using the photoresist PR as shown in FIG. 10 to expose the channel region like "H3" PR) is removed.

A source drain is formed of the first transparent metal 115 so as to cover the semiconductor layer 112b, the impurity layer 113 and the ohmic contact layer 114 located on the buffer layer 111 as shown in FIG. 11 . The first transparent metal layer 115 may be formed of any one of ITO (Indium Tin Oxide), IZO (Indium Tin Zinc Oxide), ITZO (Indium Tin Zinc Oxide), and AZO (Al2O3 doped ZnO).

The first transparent metal layer 115 is etched to expose a channel region such as "H4 ", so that the first transparent metal layer 115 is exposed to the source electrode 115a and the drain electrode 115b Respectively.

As shown in FIG. 13, a first insulating layer 116 is formed to cover the first transparent metal layer 115. The first insulating layer 116 may be formed of silicon oxide (SiOx), silicon nitride (SiNx), or a multilayer thereof, but is not limited thereto. A gate metal 117a is formed on the first insulating film 116. [ The gate metal 117a may be formed of a material selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Ne, A single layer made of any one selected, or a multi-layer made of an alloy thereof.

As shown in FIG. 14, a gate metal 117a formed on the first insulating film 116 is patterned to form a gate 117b.

The first insulating film 116 located in a region corresponding to the source electrode 115a and the drain electrode 115b is etched to form a contact hole as shown in FIG.

A second transparent metal 118 is formed on the first insulating film 116, as shown in FIG. The second transparent metal 118 may use the same material as the first transparent metal 115, but is not limited thereto.

As shown in Fig. 17, the second transparent metal 118 formed on the first insulating film 116 is patterned. When patterning the second transparent metal 118, patterns are formed except for portions connected to the gate 117b, the source electrode 115a and the drain electrode 115b. Accordingly, the second transparent metal 118 is divided into "118a" and "118b ".

The second insulating layer 119 is formed to cover the second transparent metals 118a and 118b patterned on the first insulating layer 116 as shown in FIG. As the second insulating film 119, the same material as the first insulating film 116 may be used, but the present invention is not limited thereto.

A contact hole is formed as shown in FIG. 19, such as "H6" to expose the source electrode 115a and the drain electrode 115b formed under the second insulating film 119. [

As shown in FIG. 20, a third transparent metal 120 is formed on the second insulating film 119. The third transparent metal 120 may be made of the same material as the first transparent metal 115 or the second transparent metal 118 but is not limited thereto. Here, the third transparent metal 120 is a lower electrode of the light emitting portion. The lower electrode may be selected as the cathode of the light emitting portion.

The bank layer 121 is formed on the third transparent metal 120, as shown in Fig. The bank layer 121 may include organic materials such as benzocyclobutene (BCB) based resin, acrylic based resin or polyimide resin, but is not limited thereto. And is patterned to expose a part of the third transparent metal 120 when the bank layer 121 is formed.

As shown in FIG. 22, an organic light emitting layer 122 is formed on the exposed third transparent metal 120. The organic light emitting layer 122 may include an electron transporting layer, an electron injecting layer, a light emitting layer, a hole injecting layer, and a hole transporting layer. The electron injection layer plays a role of facilitating the injection of electrons, and Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq or SAlq can be used. The electron transport layer plays a role of facilitating the transport of electrons and may be composed of at least one selected from the group consisting of Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq and SAlq, It does not. The light emitting layer may include materials emitting red, green, blue, and white light, and may be formed using phosphorescent or fluorescent materials. When the light-emitting layer emits red light, it contains a host material containing carbazole biphenyl (CBP) or mCP (1,3-bis (carbazol-9-yl), and bis (1-phenylisoquinoline) acetylacetonate iridium ), PQIr (acac) bis (1-phenylquinoline) acetylacetonate iridium, PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) Alternatively, the light emitting layer may be made of a fluorescent material including PBD: Eu (DBM) 3 (Phen) or perylene. However, when the light emitting layer emits green light, a host material containing CBP or mCP And a phosphorescent material including a dopant material including Ir (ppy) 3 (fac-tris (2-phenylpyridine) iridium), and alternatively may be made of a fluorescent material containing Alq3 (tris (8-hydroxyquinolino) aluminum) It may be made of material (4,6-F2ppy) 2Irpic, which contains a host material including CBP or mCP when the light-emitting layer emits blue light. Alternatively, the phosphorescent material may include a dopant material including (4,6-F2ppy) 2Irpic. but is not limited to, a fluorescent material including any one selected from the group consisting of spiro-DPVBi, spiro-6P, distyrylbenzene (DSB), distyrylarylene (DSA), PFO polymer, and PPV polymer (N, N'-diphenyl benzidine), TPD (N, N'-bis- (3-methylphenyl) -N, N -bis- (phenyl) -benzidine), s-TAD and 4,4 ', 4 "-tris (N-3-methylphenyl-N- phenylamino) -triphenylamine But is not limited thereto. The hole injecting layer may serve to smooth the injection of holes and may be formed of CuPc (cupper phthalocyanine), PEDOT (poly (3,4) -ethylenedioxythiophene), PANI (polyaniline) and NPD (N, N'-diphenyl benzidine), but the present invention is not limited thereto. Here, the present invention is not limited to this, and at least one of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be omitted.

An upper electrode 123 is formed on the organic light emitting layer 122. The upper electrode 123 may be selected as the anode of the light emitting portion. And may be formed of a transparent material such as the first to third transparent metals of the upper electrode 123 selected as the anode, but is not limited thereto.

In the foregoing description, a process sectional view for manufacturing a subpixel has been described. Hereinafter, the structure of a subpixel will be described with reference to a plan view of the subpixel. However, the insulating film is not shown because of the characteristics of the drawing.

Figs. 23 to 31 are plan structural views of the subpixels shown in Figs. 5 to 22. Fig.

Referring to FIG. 23, a subpixel according to the embodiment includes an element region DA and a non-element region NA. In the element region DA, the semiconductor layer 114 of the switching transistor and the driving transistor, in which the channel region is exposed, such as "H3"

Referring to FIG. 24, in the subpixel according to the embodiment, the source electrode 115c and the drain electrode 115d of the switching transistor are formed in the device region DA in accordance with the processes of FIGS. 11 and 12. Here, the source electrode 115c of the switching transistor is connected to the data line, and the drain electrode 115d is the first electrode of the capacitor.

Referring to Fig. 25, in the subpixel according to the embodiment, the switching transistor and the gate 117b of the driving transistor are formed in the device region DA, respectively, according to the processes of Figs. 13 and 14, respectively. At this time, the negative power supply wiring 117d to which the negative power is supplied is also formed in the region where the first electrode of the capacitor is located with the same material as the gate 117b. The negative power supply wiring 117d can be wired in parallel with the gate 117b which is the scan wiring located in the element region DA.

Referring to FIG. 26, the sub-pixel according to the embodiment has contact holes H and HH formed on the electrodes of the switching transistor and the driving transistor in the device region DA, respectively, according to the process of FIG.

Referring to FIG. 27, in the subpixel according to the embodiment, the drain of the switching transistor and the gate of the driving transistor are connected by the second transparent electrode 118a through the contact hole H, according to the processes of FIGS. 16 and 17 . The drain electrode of the driving transistor is connected to the negative power supply wiring 117d by the second transparent electrode 118c through the contact hole HH, which becomes the second electrode of the capacitor. The switching transistor ST1, the driving transistor T1 and the capacitor Cst are completed in accordance with the above process.

Referring to FIG. 28, according to the embodiment, the source electrode 115b of the driving transistor T1 is connected to the third transparent electrode 120, which is the cathode of the light emitting portion, according to the processes of FIGS. 19 and 20.

Referring to FIG. 29, a subpixel according to an embodiment includes a bank layer 121 having an opening region to expose a part of the third transparent electrode 120 according to the process of FIG. The opening region is defined as an element region DA. Here, the previously formed negative power supply wiring 117d is located inside the opening region defined by the bank layer 121. [

Referring to FIG. 30, the subpixel according to the embodiment has the organic light emitting layer 122 formed in the opening region defined by the bank layer 121 according to the process of FIG.

Referring to FIG. 31, the subpixel according to the embodiment has the upper electrode 123 formed on the organic light emitting layer 122 according to the process of FIG. The upper electrode 123 may be selected as an anode.

32 is a top view of the connection structure of the upper electrode, and FIG. 33 is a wiring structure diagram connected to the sub pixels.

Referring to Figure 32, red, green, and blue subpixels (R, G, B) are shown. The upper electrode 123 formed according to the process of FIG. 31 is located along the device region DA of the red, green, and blue subpixels R, G, The upper electrode 123 thus formed is connected to a positive power supply line for supplying a positive power, though it is not shown. Accordingly, when the driving transistor is driven, the light emitting unit receives the positive power through the upper electrode 123. [

33, a wiring structure is shown. The illustrated wiring 117 may be any one of a data wiring connected to the sub-pixel, a scan wiring, and a negative power wiring. In the case of the subpixel according to the embodiment, the wiring 117 for supplying the data signal, the scan signal, and the negative power supply is connected to the first transparent electrode 1st, silver (2nd) and second transparent electrode (3rd) Layer structure having a three-layer structure. As described above, the first and second transparent electrodes (1st and 3rd) are formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or AZO But it is not limited thereto. Alternatively, the wiring 117 may be formed as a two-layer cap structure including a transparent electrode (2nd) covering the metal electrode (1) as shown in (b). Here, the metal electrode 1 is formed of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper But is not limited thereto.

When the wiring 117 is formed as described above, the resistance can be lowered and the loss due to the resistance can be reduced. However, when the subpixel wiring according to the embodiment is formed, the data wiring located in the non-device area NA can be formed as a single layer using only transparent metal to improve the transmittance of the non-device area NA.

As described above, an embodiment of the present invention provides an organic electroluminescent display device in which objects located on the rear surface of a panel are displayed on a front surface of a panel to increase utilization.

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 therefore to be understood 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 diagram of an organic light emitting display device.

Figure 2 illustrates a planar area of a subpixel according to an embodiment of the present invention.

3 is a view for explaining the size of a non-element region;

4 is a circuit configuration diagram of a sub-pixel having a 2T1C structure.

FIGS. 5 to 22 are sectional views of the process for manufacturing the sub-pixel shown in FIG.

Figs. 23 to 31 are plane structural views of the subpixels shown in Figs. 5 to 22; Fig.

32 is a connection structure diagram of the upper electrode.

33 is a wiring structure connected to subpixels;

DESCRIPTION OF THE REFERENCE NUMERALS

DA: element region NA: non-element region

110: substrate 111: buffer layer

115: first transparent electrode 116: first insulating film

118: second transparent electrode 119: second insulating film

120: third transparent electrode 121: bank layer

122: organic light emitting layer 123: upper electrode

Claims (10)

A sub-pixel located on the substrate, the sub-pixel including an element region in which a light emitting portion is located and a non-element region in which no light emitting portion is located, And the non-device area occupies 30% to 75% of the device area. And a sub-pixel located on the substrate, the sub-pixel including an element region in which an element including a transistor portion and a light emitting portion is located, and a non-element region in which the element is not located, And the non-device area occupies 30% to 75% of the device area. 3. The method according to claim 1 or 2, Wherein the device region comprises: And an opening region defining a light emitting region of the subpixel. 3. The method according to claim 1 or 2, The size of the non- And the second electrode is proportional to the size of the sub-pixel region. 3. The method of claim 2, The upper electrode included in the light- And a positive power supply line which is located along the device region of the subpixel and supplies a positive power. 3. The method of claim 2, And a negative power supply wiring for supplying negative power to the sub- Wherein the first electrode and the second electrode are wired so as to be parallel to the scan wiring located in the device region. The method according to claim 6, The subpixel comprising a bank layer defining an aperture region, The negative power supply wiring includes: Wherein the organic light emitting layer is located inside the opening region defined by the bank layer. 3. The method of claim 2, At least one of a data line connected to the sub-pixel, a scan line, and a negative power line, Wherein the organic light emitting display device has a three-layered structure including a first transparent electrode, silver, and a second transparent electrode. 3. The method of claim 2, At least one of a data line connected to the sub-pixel, a scan line, and a negative power line, Layer cap structure including a transparent electrode covering a metal electrode. 3. The method of claim 2, And the data line located in the non-device region is transparent.

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