KR101695317B1 - Organic electro luminescent device - Google Patents

Abstract

The present invention relates to a liquid crystal display device including a substrate on which a display area and a non-display area are defined outside the display area, a gate wiring and a data wiring crossing each other in the display area to define a plurality of pixel areas, A heat radiation pad connected to one end of the heat emission auxiliary wiring, a switching thin film transistor and a driving thin film transistor, a first protective layer on the entire surface of the display region, A second protective layer having a flat surface and provided with a first hole for exposing the first protective layer corresponding to the first protective layer, An organic light emitting layer separated for each pixel region, a second electrode on the entire surface of the display region, and a liquid It provides an electroluminescent device. The organic electroluminescent device of the present invention smoothly discharges heat from the organic light emitting layer to the outside through the heat dissipation auxiliary wiring and the heat dissipation pad to extend the lifetime, improve the luminance characteristic, and suppress the increase of the driving voltage.

Description

[0001] The present invention relates to an organic electroluminescent device,

The present invention relates to an organic electroluminescent device, and more particularly, to an organic electroluminescent device capable of effectively emitting heat of an organic light emitting layer.

An organic electroluminescent device, which is one of flat panel displays (FPDs), has high luminance and low operating voltage characteristics. In addition, since it is a self-luminous type that emits light by itself, it has a large contrast ratio, can realize an ultra-thin display, can realize a moving image with a response time of several microseconds (μs), has no viewing angle limit, And it is driven with a low voltage of 5 to 15 V direct current, so that it is easy to manufacture and design a driving circuit.

In addition, since the fabrication process of the organic electroluminescent device is all the deposition and encapsulation equipment, the manufacturing process is very simple.

An organic electroluminescent device having such characteristics is largely divided into a passive matrix type and an active matrix type. In a passive matrix type, a scan line and a signal line cross each other to form a matrix type device, The scan lines are sequentially driven with time in order to drive the scan lines. Therefore, in order to represent the required average luminance, the instantaneous luminance must be equal to the average luminance multiplied by the number of lines.

However, in the active matrix method, a thin film transistor (TFT), which is a switching element for turning on / off a pixel region, is disposed for each pixel region, and a driving thin film transistor A power supply line, and an organic light emitting diode, and is formed for each pixel region.

At this time, the first electrode connected to the driving thin film transistor is turned on / off in the pixel region unit, and the second electrode facing the first electrode serves as a common electrode, Thereby forming the organic electroluminescent diode.

In the active matrix system having such a constitutional characteristic, the voltage applied to the pixel region is charged in the storage capacitor StgC, and power is applied until the next frame signal is applied, Continue to run for one screen without. Accordingly, since the same luminance is exhibited even when a low current is applied, an active matrix type organic electroluminescent device is mainly used since it has advantages of low power consumption, high definition and large size.

Hereinafter, the basic structure and operating characteristics of such an active matrix organic electroluminescent device will be described in detail with reference to the drawings.

1 is a circuit diagram of one pixel region of a general active matrix organic electroluminescent device.

As shown, one pixel region of the active matrix organic electroluminescent device includes a switching thin film transistor STr, a driving thin film transistor DTr, a storage capacitor StgC, and an organic electroluminescent diode E.

A gate line GL is formed in a first direction and a second direction intersecting the first direction to define a pixel region P together with the gate line GL and a data line DL is formed And a power supply line PL for applying a power supply voltage is formed at a distance from the data line DL.

A switching thin film transistor STr is formed at the intersection of the data line DL and the gate line GL and is electrically connected to the switching thin film transistor STr in each pixel region P A driving thin film transistor DTr is formed.

At this time, the driving thin film transistor DTr is electrically connected to the organic light emitting diode E. That is, the first electrode, which is one terminal of the organic electroluminescent diode E, is connected to the drain electrode of the driving thin film transistor DTr, and the second electrode, which is the other terminal, is connected to the power supply line PL. At this time, the power supply line (PL) transfers the power supply voltage to the organic light emitting diode (E). A storage capacitor StgC is formed between the gate electrode and the source electrode of the driving thin film transistor DTr.

Therefore, when a signal is applied through the gate line GL, the switching thin film transistor STr is turned on and the signal of the data line DL is transmitted to the gate electrode of the driving thin film transistor DTr, The transistor DTr is turned on so that light is output through the organic electroluminescent diode E. At this time, when the driving thin film transistor DTr is turned on, a level of a current flowing from the power supply line PL to the organic light emitting diode E is determined. Accordingly, the organic light emitting diode E The storage capacitor StgC is capable of maintaining a constant gate voltage of the driving thin film transistor DTr when the switching thin film transistor STr is turned off The level of the current flowing through the organic light emitting diode E can be kept constant until the next frame even if the switching thin film transistor STr is turned off.

FIG. 2 is a schematic plan view of a conventional organic electroluminescent device, and FIG. 3 is a cross-sectional view of one pixel region including a driving thin film transistor in a conventional organic electroluminescent device.

In the conventional organic EL device 90, a display area AA for displaying an image and a non-display area NA are provided outside the display area AA. A plurality of gate and data lines 5 and 30 are defined in the display area AA to define a pixel area P and are connected to one ends of the gate and data lines 5 and 30, A driving IC (D-IC) is provided in the non-display area NA.

Further, a power supply line 38 is formed in parallel with the data line 30 through the pixel regions P, respectively. At this time, the power supply wiring 38 is also connected to the driving IC (D-IC).

In each pixel region P, source and drain electrodes 33 and 36, which are connected to the gate and data lines 5 and 30 and are spaced apart from the gate electrode 7, the gate insulating film 12, and the semiconductor layer 20, (Not shown), and has the same structure as the driving thin film transistor DTr and is connected to the gate and the data lines 5 and 30 and has a switching thin film transistor (not shown) .

The first electrode 73 is connected to the drain electrode 36 of the driving thin film transistor DTr and is patterned for each pixel region P so that the first electrode 73 overlaps the edge of the first electrode 73 A bank 71 is provided at the boundary of each pixel region P.

The organic light emitting layer 76 contacts the first electrode 73 at the central portion of the pixel region P surrounded by the bank 71. The organic light emitting layer 76 and the bank 71 And a second electrode 78 is formed on the entire surface of the display area AA. At this time, the first electrode 71, the organic light emitting layer 76, and the second electrode 78 constitute an organic light emitting diode E.

Corresponding to the substrate 1 having the organic electroluminescent diode E as described above, the opposing substrate 81 provided with a seal pattern (not shown) along its rim is opposed at a predetermined distance. At this time, a getter 83 is provided on the inner surface of the counter substrate 81.

The getter 83 mitigates heat generated by out gassing generated from the organic light emitting layer 76 when the organic electroluminescent diode E is driven, It removes moisture.

However, as described above, the organic electroluminescent element 90 having the counter substrate 81 including the getter 83 is formed on the substrate 1 , 81 and the getter 83, and can be relatively smoothly discharged to the outside.

However, since the organic electroluminescent device having the counter substrate 81 including the getter 83 described above has low flexibility and does not reflect the trend of light weight and thinness of display devices in recent years, An organic electroluminescent device having a moisture permeation preventive film having a characteristic has been proposed.

4 is a cross-sectional view of one pixel region including a driving thin film transistor in an organic electroluminescent device including a conventional moisture barrier film. Here, the same reference numerals are given to the same components as those shown in FIG.

As shown in the figure, the upper portion of the second electrode 78 corresponds to a part of the front surface of the display area AA and a part of the non-display area NA and is provided for preventing moisture permeation from the outside and protecting the organic electroluminescent diode E The moisture permeation prevention film 80 is provided to form the organic electroluminescent device 90.

 However, the organic electroluminescent device 90 having the conventional moisture barrier film having the above-described structure is not provided with the counter substrate and the moisture absorbent spaced apart from each other at a predetermined interval, and is in direct contact with the organic electroluminescent diode E, When a voltage is applied to the first and second electrodes 73 and 78 and the organic light emitting layer 76 emits light due to the film 80, heat is generated from the organic light emitting layer 76. 76 are blocked by the moisture permeation preventive film 80 so that the heat is not smoothly discharged to the outside.

As a result, the deterioration of the organic light-emitting layer 76 progresses at a high speed over time, shortening the lifetime, increasing the driving voltage and decreasing the luminance, increasing the luminance unevenness in the display region, And the like.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide an organic light emitting diode having a structure in which heat emitted from an organic light emitting layer can be smoothly discharged to the outside, And an object of the present invention is to provide an organic electroluminescent device having luminance characteristics.

In order to achieve the above object, an organic electroluminescent device according to the present invention includes: a substrate having a display region including a plurality of pixel regions and a non-display region defined outside thereof; A gate wiring and a data wiring formed to define the plurality of pixel regions crossing each other in the display region; A power supply wiring formed to pass through each pixel region in parallel with the gate wiring or the data wiring; A heat dissipation auxiliary wiring formed through each pixel region in parallel with the gate wiring or the data wiring; A heat dissipation pad connected to one end of the heat dissipation auxiliary wiring in the non-display area; A switching thin film transistor and a driving thin film transistor formed in each pixel region; A first protective layer formed on the entire surface of the display region above the switching and driving thin film transistor; A second passivation layer formed on the first passivation layer and having a flat surface over the first passivation layer, the first passivation layer exposing the first passivation layer corresponding to the heat dissipation auxiliary wiring; A first electrode formed on each of the pixel regions on the second passivation layer so as to be in contact with a drain electrode of the driving thin film transistor and extending to the first hole and overlapping the heat dissipation auxiliary wiring in the first hole; An organic light emitting layer formed separately on the first electrode for each pixel region; A second electrode formed on the entire surface of the display region on the organic light emitting layer; And a moisture permeation preventive layer covering the second electrode and formed on the entire surface of the display area.

The heat dissipation pad has a width of several micrometers to several millimeters. The heat dissipation pad is connected to the ends of a plurality of neighboring heat dissipation auxiliary wires.

Further, the heat radiation pad is characterized in that it is exposed to air.

The gate wiring and the data wiring are connected to the switching thin film transistor, and the switching thin film transistor and the power wiring are connected to the driving thin film transistor.

The first passivation layer may be formed of an inorganic insulating material and may include a drain contact hole exposing a drain electrode of the driving TFT. The first passivation layer may have a thickness of about 1000 Å to about 3000 Å to be.

A drain auxiliary electrode is formed on the first passivation layer to contact the drain electrode of the driving thin film transistor through the drain contact hole. A drain auxiliary contact hole exposing the drain auxiliary electrode is formed in the second passivation layer. And the first electrode is in contact with the drain auxiliary electrode through the drain auxiliary contact hole.

Further, the substrate is characterized by being made of any one of plastic, polymer film and metal thin film.

In addition, a bank is formed on the first electrode so as to surround the first electrode and formed at a boundary of each pixel region.

The switching and driving thin film transistor includes a gate electrode, a gate insulating film formed on the gate electrode, an active layer of amorphous silicon formed on the gate insulating film in correspondence with the gate electrode, and an impurity amorphous A first region of pure polysilicon and a second region of polysilicon doped with impurities on both sides of the first region; and a source region and a drain region which are spaced apart from each other above the ohmic contact layer, A gate electrode formed to correspond to the first region, and a semiconductor layer contact hole formed over the gate electrode and exposing the second region, respectively, An interlayer insulating film formed on the interlayer insulating film, It is characterized by each of contact with the second region through the taekhol and consisting of a source and a drain electrode spaced from each other.

The moisture permeation preventive layer is characterized by being made of a transparent inorganic film or a face seal.

The organic electroluminescent device according to the present invention is advantageous in that it has excellent flexibility and light weight by being provided with a thin film in direct contact with the organic electroluminescent diode without a counter substrate.

In addition, the first electrode formed in each pixel region and the first electrode formed in direct contact with the organic light emitting device according to the present invention and the protective layer having a relatively small thickness are interposed between the first electrode and the second electrode. The heat generated from the organic light emitting layer is smoothly discharged to the outside through the heat dissipation auxiliary wiring and the heat dissipation pad to shorten the deterioration speed of the organic light emitting layer, The luminance uniformity and the luminance characteristic on the entire display region are improved, and the driving voltage is suppressed from rising.

1 is a circuit diagram of one pixel region of a general active matrix organic electroluminescent device.
2 is a schematic plan view of a conventional organic electroluminescent device.
3 is a cross-sectional view of one pixel region including a driving thin film transistor in a conventional organic electroluminescent device.
4 is a cross-sectional view of one pixel region including a driving thin film transistor in an organic electroluminescent device including a conventional moisture barrier film.
5 is a schematic plan view of an organic electroluminescent device according to the present invention.
6 is a sectional view of one pixel region including a driving thin film transistor in an organic electroluminescent device according to the present invention.
7 is a cross-sectional view of a heat dissipation pad portion of an organic electroluminescent device according to the present invention.
8 is a graph showing the measurement of luminance in a display region of a conventional organic electroluminescent device.
9 is a graph showing the measurement of luminance in a display region of an organic electroluminescent device according to the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

FIG. 5 is a schematic plan view of an organic electroluminescent device according to the present invention, FIG. 6 is a cross-sectional view of one pixel region including a driving thin film transistor in the organic electroluminescent device according to the present invention, Sectional view of a heat dissipation pad portion of an organic electroluminescent device according to the present invention.

As shown, the organic electroluminescent device 190 according to the present invention is provided with a display area AA for displaying an image and a non-display area NA outside the display area AA.

A plurality of pixel regions P intersecting each other in the display region AA on the substrate 101, which is made of a metal, a plastic, or a polymer film having a flexible characteristic that forms the base of the organic EL device 190, And includes a plurality of gate wirings 105 and data wirings 130. The power wirings 138 extend through the pixel regions P in parallel with the gate wirings 105 or the data wirings 130, Respectively. At this time, one end of the gate wiring 105, the data wiring 130, and the power supply wiring 138 is connected to a driving IC (D-IC) provided in the non-display area NA.

On the other hand, when the substrate 101 having the flexible characteristics is made of the metal material, a planarization layer 103 made of an organic insulating material and a buffer layer 104 made of an inorganic insulating material are further provided on the substrate 101 . In the drawing, the substrate 101 is made of a metal material, more precisely, stainless steel (SUS), and the planarization layer 103 and the buffer layer 104 are formed thereon.

The non-display area NA in which the driving IC (D-IC) is not provided is the most characteristic configuration of the organic electroluminescent device 190 according to the present invention. And a plurality of heat dissipation auxiliary wirings 141 are provided in parallel with the data wirings 130. The plurality of heat dissipation auxiliary wirings 141 are connected to one end of the plurality of heat dissipation pads 146, The plurality of heat dissipation auxiliary wirings 141 are formed to penetrate each pixel region P and are formed to overlap with the first electrode 173 of the organic electroluminescent diode E .

At this time, the number of the heat-radiating pads 146 is less than the number of the heat-radiating auxiliary wirings 141, so that a plurality of neighboring heat-radiating auxiliary wirings 141 are connected to one heat-radiating pad 146 as one group .

The reason why the heat dissipation pad 146 and the heat dissipation auxiliary wiring 141 are formed to have the above-described structure is to maximize the heat dissipation into the atmosphere.

Typically, the wiring provided in the display area AA has a width of several micrometers to several tens of micrometers. Even if one end of the wiring is exposed to the air, the area of contact with the air is small, The heat radiation pads 146 are formed so as to have widths of several tens to several tens of times greater than the width of about 탆 (width of several tens of 탆 to several mm), thereby maximizing the heat radiation efficiency by increasing the area of contact with air .

Since the heat-dissipating auxiliary wiring 141 is electrically connected and is not an element for controlling the constituent elements provided in each pixel region P, the heat-radiating auxiliary wiring 141 may be formed so that its ends are connected to each other. 146 are connected to a plurality of heat dissipation auxiliary wirings 141.

The plurality of heat dissipation auxiliary wirings 141 are formed in the same layer in which the data lines 130 are formed in parallel with the data lines 130 to form driving ICs D- A plurality of heat radiation pads 146 are formed in the non-display area NA provided with the display area AA and the non-display area NA opposed to the display area AA, (NA) in which a driving IC (D-IC) connected to the gate wiring 105 is formed by being formed in parallel with the gate wiring 105 in the same layer on which the gate wiring 105 is formed, Display area NA opposed to each other with the pixel electrode AA interposed therebetween.

A switching thin film transistor (not shown), which is a switching element, is connected to the gate wiring 105 and the data wiring 130 intersecting with each other in each pixel region P in the display area AA. A thin film transistor (not shown) and the power supply wiring 138 are formed and a driving thin film transistor DTr is formed.

The gate electrode 107, the gate insulating film 112, the active layer 120a of pure amorphous silicon, and the upper portion of the gate electrode 107, the impurity amorphous silicon, The switching thin film transistor (not shown) also has the same structure as that of the driving thin film transistor DTr. The switching thin film transistor 120b includes a semiconductor layer 120 and source and drain electrodes 133 and 136 spaced apart from each other. Have.

Although the switching and driving thin film transistor (not shown) (DTr) is formed in the bottom gate type in the drawing, it is also possible to use a polysilicon layer composed of a first region of pure polysilicon and a second region doped to both sides thereof A source electrode and a drain electrode which are in contact with the second region and are spaced apart from each other through an interlayer insulating film and a semiconductor layer contact hole each having a semiconductor layer, a gate insulating film, a gate electrode and a semiconductor layer contact hole exposing the second region, May be formed in a top gate shape.

Although one driving thin film transistor DTr is shown in each pixel region P in the drawing, a plurality of the driving thin film transistors DTr may be formed.

A drain contact hole (not shown) for exposing the drain electrode 136 of the driving thin film transistor DTr in each pixel region P is formed on the driving and switching thin film transistor DTr, 152 are provided on the first protective layer 150.

A drain auxiliary electrode 160 is formed on the first passivation layer 150 to contact the drain electrode 136 of the driving TFT DTr through the drain contact hole 152. The drain auxiliary electrode 160 is formed in the second passivation layer 170 and the drain electrode 136 of the driving thin film transistor DTr and the first electrode 173 formed for each pixel region P, Which is formed for the purpose of process stability during formation.

Next, a second passivation layer 170 is formed over the drain auxiliary electrode and the first passivation layer 150, which is made of an organic insulating material and overcomes the step due to the underlying components, . A drain auxiliary contact hole 172a is formed in the second passivation layer 170 to expose the drain auxiliary electrode 160 in each pixel region P and corresponds to the heat dissipation auxiliary wiring 141 A first hole 172b in the form of a trench for exposing the first passivation layer 150 overlapping with the heat dissipation auxiliary wiring 141 to improve thermal conductivity as the heat dissipation auxiliary wiring 141, Is provided.

A first electrode 173 that contacts the drain auxiliary electrode 160 through the drain auxiliary contact hole 172 for each pixel region P is formed on the second passivation layer 170 having the flat surface. Respectively. At this time, the first electrode 173 extends to the inside of the first hole 172b having a trench shape, so that the first electrode 173 overlaps the heat-dissipating auxiliary wiring 141 and the first passivation layer 150 .

Next, a bank 171 is provided at the boundary of each pixel region P overlapping with the edge of the first electrode 173. At this time, the bank 171 is formed so as to overlap the rim of the first electrode 173 surrounding the pixel region P, and the display region AA as a whole has a lattice form having a plurality of openings have.

An organic emission layer 176 is formed on the first electrode 173 at a central portion of each pixel region P surrounded by the bank 171. Here, although the organic light emitting layer 176 has a single layer structure as an example, the organic light emitting layer 176 may have a multi-layer structure in order to increase the light emitting efficiency. When the organic light emitting layer 176 has a multi-layer structure, a hole injection layer, a hole transporting layer, an emitting material layer, an electron transporting layer, Layer (electron injection layer). At this time, the hole injecting layer, the hole transporting layer, the electron transporting layer, and the electron injecting layer may be formed by changing their positions. This can be determined according to whether the first electrode 173 is made of a metal material having a low work function value to form a cathode or a metal material having a relatively high work function value to form the anode.

A second electrode 178 is formed on the organic light emitting layer 176 and the bank 171 to correspond to the entire surface of the display area AA. The organic light emitting layer 176 interposed between the first electrode 173 and the second electrode 178 and the two electrodes 173 and 178 constitutes an organic light emitting diode E.

Next, the upper portion of the second electrode 178 is protected against external moisture corresponding to a part of the display area AA and the non-display area NA, and the protection of the organic electroluminescent diode E and the flexible characteristic A transparent face seal or a transparent inorganic film 18 is provided to complete the organic EL device 190 according to the present invention.

In the organic electroluminescent device 190 according to the present invention having the above-described configuration, the most characteristic structure is that it passes through each pixel region P, and is arranged in parallel with the data wiring 130 or the gate wiring 105, The first protection layer 150 is exposed in each pixel region P corresponding to the heat dissipation auxiliary wiring 141 and the first hole 172b is formed in a ditch shape And the end of the heat dissipation auxiliary wiring 141 is provided inside the second passivation layer 170 which is flat on the surface thereof and the heat dissipation pad 146 having a width of several to several tens mm in the non- .

On the other hand, the organic light emitting layer 176 is in direct contact with the first electrode 173, and the heat generated by the emission of the organic light emitting layer 176 during driving of the organic light emitting diode 190 is a metal material The first electrode 173 and the first hole 172b are electrically connected to the first electrode 173 having excellent thermal conductivity. The first electrode 173 and the first hole 172b overlap with each other with the first passivation layer 150 interposed therebetween. And the heat conducted to the heat dissipating auxiliary wiring 141 is connected to the end of the heat dissipating auxiliary wiring 141 and is discharged to the outside through the heat dissipating pad 146 exposed in the atmosphere.

The first passivation layer 150 is formed of an inorganic insulating material having a thickness of about 1000 Å to 3000 Å, so that the heat conducting ability is superior to the second passivation layer 170 made of an organic insulating material.

Therefore, the organic EL device 190 according to the present invention has the second passivation layer 170 having a thickness of about several micrometers in order to have a flat surface, And a first hole 172b exposing the first passivation layer 150 in correspondence to the wiring 141. The first hole 172b is formed in direct contact with the organic light emitting layer 176 on the second passivation layer 170, The electrode 173 is adjacent to the heat emission auxiliary wiring 141 so that the heat generated from the organic light emitting layer 176 is conducted to the heat emission auxiliary wiring 141, As shown in Fig.

Since the heat generated from the organic light emitting layer 176 can be effectively emitted to the outside due to such a structural feature, the deterioration rate of the organic light emitting layer 176 can be lowered, the driving voltage can be prevented from rising due to deterioration of the organic light emitting layer 176, And it is possible to prevent unevenness in luminance due to irregular deterioration of the organic light emitting layer 176 in the display area AA.

FIG. 8 is a graph showing the measurement of the luminance in the display region of the conventional organic electroluminescent device, and FIG. 9 is a graph showing the measurement of the luminance in the display region of the organic electroluminescent device according to the present invention. At this time, the brightness was measured by applying a driving voltage of the same magnitude in an atmosphere of normal temperature and normal humidity in a state where a certain time has elapsed after the driving of the organic electroluminescent device, and displaying the maximum white in the entire display area.

Referring to FIG. 8, in the case of a conventional organic electroluminescent device, heat is not smoothly emitted to the outside of the organic luminescent layer, and deterioration is partially generated in the display region, It can be seen that a large difference occurs. At this time, the maximum luminance value of the conventional organic electroluminescent device was 391 nits, the minimum luminance value was 111.8 nit, and the luminance deviation (the maximum luminance value divided by the minimum luminance value) was about 3.49.

9, in the case of the organic electroluminescent device according to the present invention, heat generated from the organic light emitting layer is smoothly discharged to the outside through the heat dissipation auxiliary wiring and the heat dissipation pad, so that the luminance distribution As shown in FIG. At this time, since the brightness deviations in the upper and lower sides or the left and right in the display area hardly occur, it can be seen that the central part of the display area as a whole has a larger luminance than the edge part. The maximum luminance value was 550 nits, the minimum luminance value was 459 nits, and the luminance deviation was about 1.20.

Therefore, comparing the conventional organic electroluminescent device with the organic electroluminescent device according to the present invention in terms of luminance deviation, the organic electroluminescent device according to the present invention has a smooth luminance dissipation compared to the conventional organic electroluminescent device, It is found that the luminance uniformity in the liquid crystal display device is about three times better.

The driving voltage for realizing the brightness indicating white is raised due to the deterioration of the organic light emitting layer in the conventional case after a certain time after driving the organic electroluminescent device so that a relatively lower voltage than the voltage required for the maximum luminance display is applied The maximum luminance value is 391nit. However, in the case of the organic electroluminescent device according to the present invention, heat dissipation to the outside is performed relatively smoothly so that deterioration of the organic light emitting layer is relatively delayed, The variation in the magnitude of the driving voltage is not large, so that the maximum luminance value after the same time after driving becomes 550 nits.

Therefore, it can be seen that the organic electroluminescent device according to the present invention is also superior in terms of luminance sustainability and deterioration in luminance caused by deterioration of the luminance of the organic light emitting layer.

101: substrate 103: planarization film
104: buffer layer 105: gate wiring
107: gate electrode 112: gate insulating film
120: semiconductor layer 120a: active layer
120b: ohmic contact layer 133: source electrode
136: drain electrode 138: power supply wiring
150: first protection layer 152: drain contact hole
170: second protective layer 171: bank
172a: drain auxiliary contact hole 172b: first hole
173: first electrode 176: organic light emitting layer
178: second electrode 180: inorganic film
190: Organic electroluminescent device
AA: display area DA: drive area
DTr: driving thin film transistor E: organic light emitting diode
P: pixel area

Claims (12)

A substrate having a display region including a plurality of pixel regions and a non-display region defined outside thereof;
A gate line and a data line crossing each other in the display region to define the plurality of pixel regions;
A power wiring line passing through each pixel region in parallel with the gate wiring or the data wiring;
A heat dissipation auxiliary wiring passing through each pixel region in the display region in parallel with the gate wiring or the data wiring;
A heat dissipation pad connected to one end of the heat dissipation auxiliary wiring in the non-display area;
A switching thin film transistor and a driving thin film transistor of each pixel region;
A first protective layer on the front surface of the display region above the switching and driving thin film transistor;
A second passivation layer provided on the first passivation layer and having a flat surface over the first passivation layer, the first passivation layer exposing the first passivation layer corresponding to the heat dissipation auxiliary wiring;
And a second passivation layer formed on the second passivation layer, the first passivation layer being in contact with the drain electrode of the driving thin film transistor in each pixel region over the second passivation layer of the display region, A first electrode overlapping the auxiliary wiring;
An organic light emitting layer separated from the first electrode by each pixel region;
A second electrode on the entire surface of the display region over the organic light emitting layer;
And a moisture permeation preventive layer on the entire surface of the display region,
And an organic electroluminescent device.
The method according to claim 1,
Wherein the heat dissipation pad has a width larger than that of the heat dissipation auxiliary wiring.
3. The method of claim 2,
Wherein the heat dissipation pad is connected to the ends of a plurality of neighboring heat dissipation auxiliary wirings.
3. The method of claim 2,
Wherein the heat dissipation pad has a structure exposed to the atmosphere.
The method according to claim 1,
Wherein the gate wiring and the data wiring are connected to the switching thin film transistor, and the switching thin film transistor and the power wiring are connected to the driving thin film transistor.
The method according to claim 1,
Wherein the first passivation layer is made of an inorganic insulating material and includes a drain contact hole exposing a drain electrode of the driving thin film transistor.
The method according to claim 6,
Wherein the first passivation layer has a thickness of 1000 ANGSTROM to 3000 ANGSTROM.
The method according to claim 6,
And a drain auxiliary electrode which is in contact with a drain electrode of the driving thin film transistor through the drain contact hole is formed on the first passivation layer,
And a drain auxiliary contact hole for exposing the drain auxiliary electrode is formed in the second passivation layer,
And the first electrode is in contact with the drain auxiliary electrode through the drain auxiliary contact hole.
The method according to claim 1,
Wherein the substrate is made of plastic, a polymer film, or a metal thin film.
The method according to claim 1,
Wherein a bank is formed on an upper portion of the first electrode so as to surround the first electrode and formed at a boundary of each pixel region.
The method according to claim 1,
The switching and driving thin film transistor includes:
An active layer of amorphous silicon formed on the gate insulating film in correspondence with the gate electrode; an ohmic contact layer of impurity amorphous silicon formed on the active layer and spaced apart from the active layer; And a source and a drain electrode spaced apart from each other above the ohmic contact layer,
A semiconductor layer made of a first region of a first polysilicon or a first region of pure polysilicon and a second region of a polysilicon doped with impurities on both sides of the first region; a gate insulating film covering the semiconductor layer; An interlayer insulating film formed on the gate electrode and having a semiconductor layer contact hole for exposing the second region, and an interlayer insulating film formed on the interlayer insulating film so as to be in contact with the second region through the semiconductor layer contact hole, And source and drain electrodes spaced apart from each other.
The method according to claim 1,
Wherein the moisture permeation preventive layer comprises a transparent inorganic film or a face seal.

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