KR101850104B1 - Array substrate for organic electro luminescent device and method of fabricating the same - Google Patents

Abstract

The present invention provides a display device comprising: a substrate on which a display region having a plurality of pixel regions is defined; A switching thin film transistor and a driving thin film transistor formed in each pixel region on the substrate; A first protective layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor; And a first electrode formed on the first passivation layer in contact with the drain electrode of the driving thin film transistor for each of the pixel regions, wherein the first passivation layer has a concave structure with a central portion in each pixel region, One electrode is also concaved toward the center in each pixel region due to the influence of the first passivation layer, and a method for manufacturing the same.

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for an organic electroluminescent device and more particularly to a thin film transistor having a thin film transistor made of polysilicon as a semiconductor layer, And a method of manufacturing the same.

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 V to 15 V direct current, so that it is easy to manufacture and design a driving circuit.

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

Accordingly, the organic electroluminescent device having the above-described advantages has recently been used in various IT devices such as a TV, a monitor, and a mobile phone.

Hereinafter, the basic structure of the organic electroluminescent device will be described in more detail.

1 is a schematic cross-sectional view of one pixel region of a conventional organic electroluminescent device.

The organic electroluminescent device 1 comprises a substrate 10 for an organic electroluminescent device having an array element and an organic electroluminescent diode E and an opposing substrate 70 for encapsulation opposite thereto.

The array element included in the organic EL device substrate 10 includes a switching thin film transistor (not shown) connected to a gate and a data line, and a driving thin film transistor DTr connected to the organic light emitting diode E And the organic electroluminescent diode E comprises a first electrode 47 connected to the driving thin film transistor DTr and an organic light emitting layer 55 and a second electrode 58.

In the organic electroluminescent device 1 having such a configuration, light generated from the organic light emitting layer 55 is emitted toward the first electrode 47 or the second electrode 58 to display an image. In consideration of the aperture ratio and the like, the organic electroluminescent device 1 is generally manufactured by a top emission type in which an image is displayed using light emitted toward the second electrode 58.

In the conventional organic electroluminescent device 1 having such a configuration, when a voltage is applied to the first and second electrodes 47 and 58, electrons and holes are supplied to the organic light emitting layer 55 And recombination is performed in the organic light emitting layer 55 to generate light.

Light generated in the organic light emitting layer 55 is emitted toward the first electrode 47 and the second electrode 58 and finally passes through the second electrode 58 and the counter substrate 70 through internal reflection The light emitted from the outside through the surface of the counter substrate 70 is incident on the user's eye, so that the user can view the image.

However, since the light generated in the organic light emitting layer 55 passes through the components located above and below the organic light emitting layer 55, a loss is generated therein, so that light incident on the user's eye substantially passes through the organic light emitting layer 55 ) Is about 19% of the light emitted from the light source.

In more detail, the top emission type organic electroluminescent device 1 is formed so as to realize a microcavity effect in order to improve luminescent characteristics. That is, the first electrode 47 is formed to have a two-layer or more structure having the same shape in a planar form by successively depositing and patterning a different metal material or a transparent conductive material, and the second electrode 58 is also formed of a material So that reflection is generated between the first electrode 47 and the second electrode 58.

However, in the conventional top emission type organic electroluminescent device 1 having such a structure, light which disappears through the side surface of the first electrode 47 due to total internal reflection due to the structure characteristic of the first electrode 47 There is a problem that the reflection efficiency is lowered.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a top emission type organic electroluminescent display device capable of improving reflection efficiency by minimizing light that is emitted from a first electrode, And an object of the present invention is to provide a substrate for an organic electroluminescence device.

According to an aspect of the present invention, there is provided a substrate for an organic electroluminescent device, including: a substrate defining a display region having a plurality of pixel regions; A switching thin film transistor and a driving thin film transistor formed in each pixel region on the substrate; A first protective layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor; And a first electrode formed on the first passivation layer in contact with the drain electrode of the driving thin film transistor for each of the pixel regions, wherein the first passivation layer has a concave structure with a central portion in each pixel region, One electrode is also formed in a concave structure toward the center in each pixel region due to the influence of the first protective layer.

According to another aspect of the present invention, there is provided a substrate for an organic electroluminescent device, including: a substrate having a display region defined therein having a plurality of pixel regions; A switching thin film transistor and a driving thin film transistor formed in each pixel region on the substrate; A first protective layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor; And a first electrode formed on the first passivation layer in contact with the drain electrode of the driving thin film transistor for each pixel region on the first passivation layer. The first passivation layer includes a dam portion And a surface portion inside the dam portion. The first electrode has a shape in which each end of the first electrode is bent at an end of the dam portion in the pixel region, thereby forming a side wall. At this time, the surface of the first protective layer may have a flat shape, or may have a concave shape toward the center of each pixel region, and the bottom surface of the first protective layer may be formed to overlap with the surface portion of the first protective layer. And is formed in a flat shape or in a concave shape toward the center of each pixel region.

A bank formed on a boundary of the pixel region and overlapping an edge of the first electrode; A spacer formed on the bank; An organic light emitting layer formed on the first electrode inwardly of the bank; And a second electrode formed on the entire surface of the display region above the bank.

When the first electrode has a triple layer structure, the lower layer is made of a transparent conductive material, the intermediate layer is made of a metal material having a high reflectance, and the upper layer has a work function Layer structure, the first layer is made of a metal material having a high reflectivity, and the second layer is made of a transparent conductive material having a low work function value. .

The transparent conductive material may be indium tin oxide (ITO) or indium zinc oxide (IZO), and the metal material having excellent reflectance may be aluminum (Al), aluminum alloy (AlNd), silver (Ag) , Pd, and Cu alloy).

The first passivation layer may be formed of an organic insulating material, and a second passivation layer may be further formed under the first passivation layer.

Wherein a gate wiring and a data wiring crossing each other and defining the pixel region are formed on the substrate, and a power supply wiring arranged in parallel with the data wiring is formed, wherein the gate and the data wiring are respectively connected to the gate electrode and the source electrode And an opposite substrate for encapsulation is provided facing the substrate.

According to an aspect of the present invention, there is provided a method of manufacturing a substrate for an organic electroluminescent device, the method comprising: forming a switching thin film transistor and a driving thin film transistor in each pixel region on a substrate on which a display region having a plurality of pixel regions is defined; Forming a first passivation layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor and having a concave structure in a center portion in each pixel region; Forming a first electrode in contact with the drain electrode of each of the driving TFTs on the first passivation layer and forming a concave structure in the center of each pixel region.

The forming of the first passivation layer may include: applying a photosensitive organic insulating material over the switching and driving thin film transistors to form an organic insulating layer having a flat surface; Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask; And developing the exposed organic insulating layer, wherein the transflective region corresponding to each of the pixel regions is formed in a slit shape, and the slit gradually increases from the central portion to the edge of each pixel region Or a multilayer film made of an organic material or an inorganic material which weakens the transmittance of light is formed in a larger number or a larger thickness in the central part of each pixel area with a different number of layers or thickness, The blocking region is located corresponding to the boundary of each pixel region, and the transmissive region is located corresponding to the drain electrode.

According to another aspect of the present invention, there is provided a method of manufacturing a substrate for an organic electroluminescent device, comprising: forming a switching thin film transistor and a driving thin film transistor in each pixel region on a substrate on which a display region having a plurality of pixel regions is defined; ; A drain electrode of the driving thin film transistor is covered to cover the switching and driving thin film transistor and a first protection layer including a dam portion surrounding the pixel region at the edge of each pixel region and a surface portion inside the dam portion is formed ; A first electrode is formed on the first protective layer so as to be in contact with the drain electrode of the driving thin film transistor in each of the pixel regions and to be positioned on the upper side of the dam portion in each pixel region to have a bottom surface portion and a curved side wall portion .

The forming of the first passivation layer may include: applying a photosensitive organic insulating material over the switching and driving thin film transistors to form an organic insulating layer having a flat surface; Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask; And developing the exposed organic insulating layer, wherein the exposure mask has a structure in which the semi-transmissive region corresponding to each pixel region is formed of a multilayer film made of an organic material or an inorganic material that weakens the light transmittance , A blocking region corresponding to the dam portion is located, and the transmissive region is located corresponding to the drain electrode.

The surface portion of the first passivation layer may have a flat shape in each pixel region or a concave shape toward the center of each pixel region.

The step of forming the first passivation layer having a concave surface portion may include the steps of: applying a photosensitive organic insulating material on the switching and driving thin film transistor to form an organic insulating layer having a flat surface; Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask; And developing the exposed organic insulating layer, wherein the exposure mask comprises: a blocking region provided with a blocking layer made of a material blocking light transmission; and a transmissive region corresponding to a drain electrode of the driving thin film transistor A semi-transmissive region having a plurality of slits corresponding to the respective pixel regions and having a slit shape, the slit being progressively denser from the central portion to the edge of the pixel region, or A semi-transmissive region having a structure in which the number of layers or the thickness of the organic material or the inorganic material which weakens the transmittance of light is increased or increased toward the edge at the central portion of the pixel region, A slit structure that becomes denser toward the edge from the central portion of each pixel region, and a light transmittance It is characterized by solidifying the multi-layer having a semi-transmission region of an increasingly larger number of thicker or structure formed by overlapping the edge at the central portion of each pixel region.

Forming a bank at a boundary of the pixel region and overlapping an edge of the first electrode; Forming spacers on top of the banks; Forming an organic light emitting layer on the first electrode inside the bank; And forming a second electrode over the organic light emitting layer and the display region over the bank.

When the first electrode has a triple layer structure, a first transparent conductive material layer and a second transparent conductive material layer may be formed on the first protective layer. In this case, Forming a first electrode having the triple layer structure by sequentially forming a reflective layer made of a material and a second transparent conductive material layer, patterning the second transparent conductive material layer, the reflective layer, and the first transparent conductive material layer, When the first electrode has a double layer structure, a reflective layer made of a metal material having excellent reflectivity and a transparent conductive material layer are sequentially formed, and the reflective layer and the transparent conductive material layer are patterned to form the first electrode having the double layer structure .

In addition, a second protective layer made of an inorganic insulating material may be further formed on the switching and driving thin film transistor before forming the first protective layer.

The step of forming the switching and driving thin film transistors may include forming a gate wiring and a data wiring which cross each other to define the pixel region and a power supply wiring arranged in parallel with the data wiring, And the data line are connected to the gate electrode and the source electrode of the switching thin film transistor, respectively.

In the substrate for a top emission type organic electroluminescent device according to an embodiment of the present invention, a protective layer in which a first electrode serving as an anode electrode is located is concave in each pixel region, so that the first electrode has a concave mirror shape Or the protection layer is formed to have a dome shape corresponding to the boundary of each pixel region for each pixel region so that the first electrode is formed so that both ends of the first electrode are bent in each pixel region, It is possible to minimize the light leaked to the side surface by means of the light emitting diode.

1 is a cross-sectional view of a conventional pixel region of an organic electroluminescent device.
2 is a circuit diagram of one pixel of a general organic electroluminescent device.
3 is a sectional view of one pixel region of a substrate for a top emission type organic electroluminescence device according to the first embodiment of the present invention.
4 is a cross-sectional view of one pixel region of a substrate for a top emission type organic electroluminescence device according to a second embodiment of the present invention.
5 is a sectional view of one pixel region of a substrate for a top emission type organic electroluminescence device according to a third embodiment of the present invention.
6A to 6K are cross-sectional views illustrating steps of manufacturing one pixel region of a substrate for an organic electroluminescence device according to the first embodiment of the present invention;
7 is a view illustrating a step of forming a second protective layer in a manufacturing step of a substrate for an organic electroluminescent device according to the first embodiment of the present invention.
FIGS. 8A to 8C are cross-sectional views illustrating a pixel region of a substrate for an organic electroluminescence device according to a second embodiment of the present invention; FIG.
FIGS. 9A to 9C are cross-sectional views illustrating steps of manufacturing a pixel region of a substrate for an organic electroluminescence device according to a third embodiment of the present invention; FIGS.

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

First, the structure and operation of the organic electroluminescent device will be briefly described with reference to FIG. 2, which is a circuit diagram for one pixel of the organic electroluminescent device.

As shown in the figure, a switching thin film transistor STr, a driving thin film transistor DTr, a storage capacitor StgC, and an organic light emitting diode E are provided in one pixel region of the organic electroluminescent device .

That is, a gate line GL is formed in a first direction, a data line DL is defined by defining a pixel region P in a second direction intersecting the first direction, and the data line DL And a power supply line PL for applying a power supply voltage is formed.

A switching thin film transistor STr is formed at the intersection of the data line DL and the gate line GL and a driving thin film transistor DTr electrically connected to the switching thin film transistor STr is formed have.

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 grounded. 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 thin film transistor DTr is turned on so that light is output through the organic light emitting diode E.

At this time, when the driving thin film transistor DTr is turned on, the level of a current flowing from the power supply line PL to the organic light emitting diode E is determined, 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.

3 is a cross-sectional view of one pixel region of a substrate for a top emission type organic light emitting device according to a first embodiment of the present invention. In this case, for convenience of description, a region where the driving thin film transistor DTr is formed is referred to as a driving region DA, and a region where a switching thin film transistor is formed in each pixel region P (not shown) , And an area where the storage capacitor is formed is defined as a storage area (StgA).

As shown in the figure, in the substrate 101 for an organic EL device according to the present invention, the driving region DA and the switching region (not shown) on the insulating substrate 110 forming the base are made of pure polysilicon And a semiconductor layer 113 formed of a first region 113a forming a channel channel and a second region 113b doped with impurities at high concentration on both sides of the first region 113a.

Also, a first storage electrode 115 made of polysilicon doped with an impurity is formed in each storage region StgA.

At this time, an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiO ₂ ) is formed on the entire surface of the insulating substrate 110 between the semiconductor layer 113 and the first storage electrode 115 and the insulating substrate 110 A buffer layer (not shown) made of SiNx may be further provided.

The buffer layer (not shown) may be formed on the semiconductor layer 113 due to the release of alkali ions from the inside of the first substrate 110 during crystallization of the semiconductor layer 113 made of polysilicon and the first storage electrode 115, In order to prevent deterioration of characteristics of the semiconductor device.

A gate insulating layer 116 is formed on the entire surface of the polysilicon semiconductor layer 113 and the first storage electrode 115. The gate insulating layer 116 is electrically connected to the driving region DA and the switching region A gate electrode 120 is formed corresponding to the first region 113a of each semiconductor layer 113. In addition,

The gate insulating layer 116 is connected to a gate electrode (not shown) formed in the switching region (not shown) and extends in one direction to form a gate wiring (not shown).

A second storage electrode 118 (made of the same metal material as the gate wiring) corresponding to the first storage electrode 115 made of polysilicon doped with impurities is formed in the storage region StgA, Is formed. At this time, the first storage electrode 115, the gate insulating film 116, and the second storage electrode 118, which are sequentially stacked in the storage region StgA, form a first storage capacitor StgC1.

Next, an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiN x) is formed on the gate electrode 120, the gate wiring (not shown) and the second storage electrode 118, An interlayer insulating film 123 made of, for example, benzocyclobutene (BCB) or photo acryl is formed.

At this time, the semiconductor layer contact holes (not shown) are formed in the interlayer insulating layer 123 and the gate insulating layer 116 below the second interlayer insulating layer 123 to expose the second regions 113b located on both sides of the first region 113a, 125 are provided.

Next, a data line (not shown) is formed on the interlayer insulating layer 123 having the semiconductor layer contact hole 125 to define the pixel region P intersecting the gate line (not shown) , Power wiring (not shown) is formed so as to be spaced apart from the data wiring (not shown).

The second region of the semiconductor layer 113 exposed through the semiconductor layer contact hole 125 is separated from the driving region DA and the switching region (not shown) on the interlayer insulating layer 123, And source and drain electrodes 133 and 136 are formed to be spaced apart from each other.

On the other hand, the source and drain electrodes 133 and 136, which are separated from the semiconductor layer 113, the gate insulating film 116, the gate electrode 120, and the interlayer insulating film 123 sequentially stacked in the driving region DA, Thereby forming a driving thin film transistor DTr. At this time, a switching thin film transistor (not shown) having the same structure as the driving thin film transistor DTr formed in the driving region DA is formed in the switching region (not shown).

The switching thin film transistor (not shown) is electrically connected to the gate wiring (not shown) and the data wiring (not shown), and is further connected to the driving thin film transistor DTr.

The source electrode 133 of the driving thin film transistor DTr is extended to the storage region StgA to overlap the second storage electrode 118 and the interlayer insulating film 123, Electrode 134 is formed. At this time, the second storage electrode 118, the interlayer insulating layer 123, and the third storage electrode 134 overlap with each other to form a second storage capacitor StgC2. Thus, the first and second storage electrodes Stg1, 2 storage capacitors StgC1 and StgC2 are connected in parallel to each other via the second storage electrode 118, so that the total storage capacitor capacity is increased.

Meanwhile, the driving and switching thin film transistor DTr (not shown) forms a p-type or n-type thin film transistor according to impurities doped in the second region 113b. In the case of the p-type thin film transistor, the second region 113b is formed by doping an element of Group 3 such as boron (B). In the case of the n-type thin film transistor, For example, by doping phosphorus (P).

In the p-type thin film transistor, holes are used as carriers, and n-type thin film transistors are used as carriers.

The first electrode 147 connected to the drain electrode 136 of the driving thin film transistor DTr functions as an anode or a cathode electrode depending on the type of the driving thin film transistor DTr.

That is, when the driving thin film transistor DTr is p-type, the first electrode 147 serves as an anode electrode, and when the driving thin film transistor DTr is an n-type, the first electrode 147 serves as a cathode electrode.

In the first embodiment of the present invention, the driving thin film transistor DTr is p-type, so that the first electrode 147 serves as an anode electrode.

A protective layer 145 having a drain contact hole 143 exposing the drain electrode 136 of the driving thin film transistor DTr is formed on the driving and switching thin film transistor DTr and the second storage capacitor StgC2. (Not shown). In this case, the protective layer 141 is formed of a first protective layer 138 made of an inorganic insulating material and a second protective layer 140 made of an organic insulating material on the first protective layer 138, The protective layer 141 may be formed as a single layer structure made of an organic insulating material.

The protective layer 141 is formed by a double layer structure of a first protective layer 138 made of an inorganic film and a second protective layer 140 made of an organic film for improving the bonding property and stabilizing the process. The bonding force between the inorganic substance and the metal substance and the bonding force between the inorganic substance and the organic substance are superior to the bonding force between the organic substance and the metal substance.

The second passivation layer 140 has a surface corresponding to each pixel region P and a surface of the second protection layer 140 facing the center of each pixel region P, And has a thinner thickness than the side surface, so that the central portion of each pixel region P forms a concave shape.

The drain electrode 136 and the drain contact hole 143 of the driving thin film transistor DTr are formed on the second passivation layer 140 having a concave shape toward the center in each pixel region P, And a first electrode 147 is formed for each pixel region P. At this time, the first electrode 147 has a triple-layer structure or a double-layer structure. Further, due to the influence of the second passivation layer 140, the first electrode 147 has a concave shape Feature.

The lower layer 147a may be formed of a transparent conductive material such as indium (In), indium (In), or the like. In the case of forming a triple layer structure of a triple layer structure of the lower layer 147a, the intermediate layer 147b, and the upper layer 147c, The intermediate layer 147b located on the lower layer 147a may be formed of a metal material having a high reflectance such as an aluminum alloy (AlNd), a titanium nitride (TiN) An upper layer 147c located on the intermediate layer 147b is formed of any one of silver (Ag), APC (Ag, Pd, Cu alloy), and a transparent conductive material having a high work function value such as indium- Oxide (ITO) to serve as an anode electrode.

The reason for forming the lower layer 147a made of a transparent conductive material in the first electrode 147 is to improve the processability and reliability.

Although not shown in the drawing, the first electrode 147 may have a bilayer structure, that is, a first layer made of a metal having a high reflectivity, and an indium-tin-oxide having a relatively high work function value May be formed to have a second layer formed thereon.

As described above, the first electrode 147 is formed in a double or triple layer in the pixel region P so as to be concave toward the center, so that the first electrode 147 is formed in each pixel region P In this case, a concave mirror is formed.

Accordingly, when light generated from the organic light emitting layer (not shown) located on the first electrode 147 is incident on the first electrode 147, A part of the light exiting toward the side surface of the substrate 101 for the organic electroluminescence element by the total internal reflection at the first electrode 147 itself may be affected by the bending of the first electrode 147 itself And the light efficiency is improved.

A bank 150 is formed on the boundary of each pixel region P over the protective layer 140 while overlapping the edge of the first electrode 147 on the first electrode 147 having the above- have.

Spacers 160 are formed on the banks 150 at predetermined intervals.

An organic light emitting layer (not shown) is formed on the first electrode 147 in each pixel region P surrounded by the bank 150.

Here, the organic light emitting layer (not shown) may be a single layer made of an organic light emitting material, or may be formed from the surface of the upper layer 147c of the first electrode 147 serving as the anode electrode A hole injecting layer 155a, a hole transporting layer, an emitting material layer, an electron transporting layer, and an electron injection layer Layer structure.

Next, a second electrode (not shown) serving as a cathode electrode is formed on the entire surface of the display region on the organic light emitting layer (not shown) and the bank 150.

In this case, the second electrode (not shown) may be formed of a metal material having a low work function value such as silver (Ag), a magnesium-silver alloy (MgAg), gold (Au) (Mg), copper (Cu), and calcium (Ca), or the lower layer may be formed of a metal material having a relatively low work function value as described above, Layer structure may be formed by further providing an upper layer made of any one of indium-zinc-oxide (ITO) or indium-tin-oxide (ITO) which is a transparent conductive material.

The reason why the second electrode (not shown) is formed to have a bilayer structure is to reduce the sheet resistance of the second electrode (not shown).

The second electrode (not shown) should be formed of a metal material having a low work function value to serve as a cathode electrode in the characteristics of the upper emission type organic electroluminescent device. If the second electrode is formed too thick, It is difficult to develop the characteristics. For this purpose, if the second electrode is formed to have a small thickness, the sheet resistance is increased and the driving voltage is increased to increase power consumption. Therefore, an upper layer made of a transparent conductive material is further formed.

At this time, the first electrode 147, the organic light emitting layer (not shown) and the second electrode (not shown), which are sequentially stacked in each pixel region P, form an organic light emitting diode (not shown).

An opposite substrate (not shown) for encapsulation is provided corresponding to the substrate 101 for an organic EL device according to the first embodiment of the present invention including the above-described components. The substrate 101 and the counter substrate (not shown) are provided with an adhesive (not shown) made of a sealant or a frit along the edge thereof. The adhesive (not shown) Thereby forming an electroluminescent device.

At this time, a vacuum atmosphere is formed between the substrate 101 and the counter substrate (not shown) which are spaced apart from each other or filled with an inert gas to form an inert gas atmosphere.

The counter substrate (not shown) for the encapsulation may be made of plastic having flexibility or may be made of a glass substrate. Further, the counter substrate (not shown) may be adhered in the form of a film including an adhesive layer (Not shown) provided on the uppermost layer of the substrate 101 for the organic electroluminescent device via the first electrode (not shown).

In the substrate 101 for an organic electroluminescence element having the above-described structure, the first electrode 147 has a concave mirror shape toward the central portion in each pixel region P, so that light emitted from the organic light emitting layer (not shown) The first electrode 147 is formed on the first electrode 147. The first electrode 147 is formed on the first electrode 147. The first electrode 147 has a concave shape, .

4 is a cross-sectional view of one pixel region of a substrate for a top emission type organic light emitting device according to a second embodiment of the present invention. In this case, in the second embodiment of the present invention, most of the components are the same, and only the protective layer and the first electrode have a different form from the first embodiment. Therefore, only the protective layer and the first electrode do. Here, for convenience of description, the same reference numerals are assigned to the same components as those of the first embodiment.

The second passivation layer 240 made of an organic insulating material formed on the substrate 201 for a top emission type organic electroluminescence device according to the second embodiment of the present invention has a planar surface in the center of each pixel region P And a dam portion 240b having a dam shape along the edges of the pixel regions P, as shown in FIG.

The first electrode 247 is formed in contact with the drain electrode 136 of the driving TFT DTr for each pixel region P over the second passivation layer 240 having the above-described structure. At this time, the first electrode 247 is formed in a container shape whose end is extended to the upper surface of the dam portion 240b of the second protective layer 240 so that the sectional shape of the first electrode 247 is depressed.

That is, the first electrode 147 provided in each pixel region P has a bottom surface portion 246 having a flat surface and a side surface portion 246 formed by bending the edge of the bottom surface portion 246 to form a side wall 248).

Accordingly, the first electrode 247 having such a shape is increased in reflectivity of light incident from the organic light emitting layer (not shown) formed on the first electrode 247 by the side portion 248 toward the first electrode 247 And by having the bent portion itself, the light emitted from the first electrode 247 to the side due to total internal reflection is suppressed, thereby improving the light efficiency as in the first embodiment.

Components other than the protective layer and the first electrode 247 are the same as those of the organic electroluminescent device according to the first embodiment, and a description thereof will be omitted.

FIG. 5 is a cross-sectional view of a substrate for a top emission type organic light emitting device according to a third embodiment of the present invention, taken along one pixel region P. FIG. In the third embodiment of the present invention, most of the components are the same. Since only the second protective layer and the first electrode are differentiated from the first embodiment, the second protective layer and the first protective layer, Only the electrode will be described. Here, for convenience of description, the same reference numerals are assigned to the same components as those of the first embodiment.

A substrate 301 for an organic electroluminescence device according to a third embodiment of the present invention is provided on a substrate for an organic electroluminescence device according to the first and second embodiments (201 in FIG. 3, 301 in FIG. 4) (140 in Fig. 3, 240 in Fig. 4) and the first electrode (147 in Fig. 3, 247 in Fig.

That is, the second passivation layer 340 has a bottom portion 340a corresponding to each pixel region and having a concave shape toward the center, and a dam portion 340b as a dam shape at the edge of each pixel region P It is characterized in that it is constituted.

The first electrode 347 provided in each pixel region P above the second passivation layer 340 having such a shape may have a concave bottom face 346 and an edge of the bottom face 346, And a side surface portion 348 bent along the dam portion 340b of the second protective layer 340 and formed on the side surface of the dam portion 340. [

In the case of the second protective layer 340 having such a configuration, the generated light is most effectively reflected upward from the organic light emitting layer (not shown) formed on the first electrode 347, and the first electrode 347 itself The first electrode 347 and the first electrode 347 are integrally formed with the first electrode 347 and the second electrode 346. The first electrode 347 and the first electrode 347 are electrically connected to each other, (147 in FIG. 3 and 247 in FIG. 4), the light efficiency can be improved.

Hereinafter, a method of manufacturing the substrate for an organic EL device according to the first, second, and third embodiments will be described.

6A to 6K are cross-sectional views illustrating steps of manufacturing a pixel region (P) of a substrate for an organic electroluminescence device according to a first embodiment of the present invention. For convenience of description, a region where a thin film transistor is formed in each pixel region P is defined as an element region DA, and a region where a storage capacitor is formed is defined as a storage region StgA, And a switching thin film transistor (not shown) connected to a gate and a data line (not shown) has the same structure as the driving thin film transistor DTr It is not shown because it has.

First, as shown in FIG. 6A, silicon nitride (SiNx) or silicon oxide (SiO ₂ ), which is an inorganic insulating material, is deposited on the insulating substrate 110 to form a buffer layer 111. When the amorphous silicon layer is recrystallized as a polysilicon layer, the buffer layer 111 may be formed by alkali ions such as potassium ions (K +) existing in the insulating substrate 110 due to heat generated by laser irradiation or heat treatment, ), Sodium ions (Na < + >), and the like can be generated. In order to prevent the film characteristics of the semiconductor layer made of polysilicon from being deteriorated by the alkali ions. At this time, the buffer layer 111 may be omitted depending on what kind of material the substrate 110 is made of.

Thereafter, amorphous silicon is deposited on the buffer layer 111 to form a pure amorphous silicon layer (not shown) on the entire surface of the substrate 110.

Next, the pure amorphous silicon layer (not shown) is crystallized to improve the mobility characteristics of the pure amorphous silicon layer (not shown) to form a pure polysilicon layer 180. At this time, it is preferable that the crystallization process is a solid phase crystallization (SPC) or a crystallization process using a laser.

The solid phase crystallization (SPC) process may be performed by, for example, thermal crystallization through heat treatment in an atmosphere at 600 ° C. to 800 ° C., alternating magnetic (Magnetic) crystallization in a temperature atmosphere of 600 ° C. to 700 ° C. using an alternating- Field Crystallization) process, and the crystallization using the laser is preferably an excimer laser annealing (ELA) method using an excimer laser or a sequential lateral solidification (SLS) crystallization.

Next, as shown in FIG. 6B, the polysilicon layer (180 in FIG. 6A) is subjected to a mask process including photoresist application, exposure using an exposure mask, development of exposed photoresist, and etching and strip unit processes A semiconductor layer 113 of polysilicon is formed in the device region DA and a polysilicon semiconductor pattern 114 is formed in the storage region StgA. At this time, the semiconductor pattern 114 becomes a first storage electrode (115 of FIG. 6C) after the conductive property is improved by doping with impurities.

Next, by depositing the semiconductor pattern 114 and the polysilicon semiconductor layer 113 over the insulation to the front arms, for materials for example of silicon nitride (SiNx) or silicon oxide (SiO ₂₎ as shown in Figure 6c gate An insulating film 116 is formed.

Then, a photoresist layer 190 is formed on the gate insulating layer 116 to correspond to the driving region DA by patterning the photoresist layer (not shown).

Next, using the photoresist pattern 190 as a blocking mask, impurities are doped in the semiconductor pattern (114 in FIG. 6B) made of pure polysilicon to improve conductivity to form the first storage electrode 115.

Next, as shown in FIG. 6D, the photoresist pattern 190 (FIG. 6C) is removed by advancing the strip to expose the gate insulating layer 116.

Thereafter, a low resistance metal material such as aluminum (Al), aluminum alloy (AlNd), copper (Cu), copper alloy, molybdenum (Mo), molybdenum (MoTi) Or two or more materials may be deposited to form a single layer or multilayer structure of a gate metal layer (not shown).

Next, a gate wiring (not shown) extending in one direction is formed at the boundary of the pixel region P by patterning the gate metal layer (not shown) through a masking process, and at the same time, A gate electrode 120 is formed corresponding to a central portion of the semiconductor layer 113 of silicon and a second storage electrode 118 is formed in the storage region StgA. At this time, the first storage electrode 115, the gate insulating film 116, and the second storage electrode 118, which are sequentially stacked in the storage region StgA, form a first storage capacitor StgC1.

Next, as shown in FIG. 6E, the semiconductor layer 113 of the polysilicon is doped with an n-type impurity or a p-type impurity using the gate electrode 120 as a doping mask, The ohmic contact layer 113b doped with impurities is formed on both sides of the ohmic contact layer 113b. At this time, the region of the semiconductor layer 113 of polysilicon, which is not doped with the gate electrode 120, forms an active layer 113a made of pure polysilicon.

Next, as shown in FIG. 6F, silicon oxide (SiO ₂ ) or silicon nitride (SiN x), which is an inorganic insulating material, is formed over the gate electrode 120, the gate wiring (not shown) and the second storage electrode 118, Or an organic insulating material, such as benzocyclobutene (BCB) or photo acryl, is applied to form an interlayer insulating film 123. In this case,

Thereafter, the interlayer insulating layer 123 is masked and patterned together with the gate insulating layer 116 to expose the ohmic contact layer 113b outside the active layer 113a of the semiconductor layer 113 The semiconductor layer contact hole 125 is formed.

Next, as shown in FIG. 6G, a metal material such as aluminum (Al), an aluminum alloy (AlNd), copper (Cu), copper (Cu), or the like is formed on the entire surface of the interlayer insulating film 123 on which the semiconductor layer contact hole 125 is formed. A second metal layer (not shown) is formed by depositing any one or two or more of alloys, molybdenum (Mo), and molybdenum (MoTi).

A data line (not shown) is formed on the boundary of the pixel region P so as to cross the gate line (not shown) to define the pixel region P by patterning the second metal layer (not shown) And power supply wiring (not shown) is formed so as to be spaced apart from the data wiring (not shown).

At the same time, the source and drain electrodes 133 and 136 are formed in contact with the ohmic contact layer 113b through the semiconductor layer contact hole 125 in the device region DA. At this time, the drain electrode 136 extends to the storage region StgA to form the third storage electrode 134.

The second storage electrode 118, the interlayer insulating layer 123 and the third storage electrode 134 constitute a second storage capacitor StgC2 in the storage region StgA, The second storage capacitors StgC1 and StgC2 are connected in parallel to each other via the second storage electrode 118, thereby increasing the total storage capacitor capacity.

Next, as shown in FIG. 6H, an inorganic insulating material example is formed on the entire surface of the source and drain electrodes 133 and 136, the data wiring (not shown), the power supply wiring (not shown), and the third storage electrode 134 g of silicon oxide (SiO ₂₎ or by depositing a silicon nitride (SiNx) forming a first passivation layer 138, and subsequently the first protective layer 138 to the top of benzocyclobutene (BCB), an organic insulating material or picture The second protective layer 140 having a flat surface is formed by overcoming the step of the lower component by applying a photo acryl. At this time, the second passivation layer 140 has a positive type photosensitive property with a characteristic of being removed upon development upon receiving light.

The first passivation layer 138 may be omitted. When the first passivation layer 138 is formed, a masking process is performed to pattern the first passivation layer 138, The primary drain contact hole 139 exposing the drain electrode of the transistor DTr is formed.

The transmissive region TA and the transmissive region TA are formed on the second passivation layer 140 in such a manner that light transmission is smaller than the light blocking region BA and the transmissive region TA and corresponding to each pixel region P, (MSK) having a transflective region (HTA) with a light transmittance in the range of 10% to 90% of the light transmittance of the transparent substrate (TA).

At this time, the transmissive area TA corresponds to the drain electrode 136 of the thin film transistor DTr, the blocking area BA corresponds to the boundary of each pixel area P, and each pixel area P The exposure mask MSK is positioned such that the semitransmissive area HTA corresponds to the opening of the exposure mask MSK.

 The exposure mask MSK is formed in a slit shape as shown in (HTA) of a transflective region corresponding to each pixel region P, and a slit is formed in a central portion of the pixel region P, 7 (the step of forming the second protective layer in the manufacturing step of the substrate for an organic EL device according to the first embodiment of the present invention) As described above, the multilayer films L1, L2, and L3 made of an organic material or an inorganic material that weakens the light transmittance are formed in a larger number or a greater thickness from the central portion of the pixel region P toward the edge, Structure.

Thus, when the second passivation layer 140 is exposed using the exposure mask MSK having such a structure and the developing process is performed thereon, the blocking region (BA in FIG. 6I) (HTA in FIG. 6I), the second protective layer 140 is formed as a flat surface at the boundary of each pixel region P corresponding to the light blocking portion, The thickness gradually decreases toward the central portion of each pixel region P to be a concave shape. Since the portion corresponding to the drain electrode 136 of each driving TFT DTr is gradually exposed to the light toward the center portion, The drain contact hole 143 exposing the drain electrode 136 is formed.

When the first passivation layer 138 is formed, the second passivation layer 140 may be formed to penetrate the primary drain contact hole 139 (FIG. 6I) provided in the first passivation layer 138, A contact hole 143 is formed.

Then, a transparent conductive material having a high work function value such as indium-tin-oxide (ITO) is deposited on the entire surface of the second passivation layer 140 having a concave shape corresponding to the drain contact hole 143 and each pixel region ITO) or indium-zinc-oxide (IZO) is deposited on the entire surface and a masking process is performed and patterned to form a first electrode 147 that contacts the drain electrode 136 through the drain contact hole 143 .

In this case, before the transparent conductive material is deposited on the second passivation layer 140, a metal material having excellent reflectivity, such as aluminum (Al), an aluminum alloy (AlNd ) And silver (Ag) are deposited first and then a transparent conductive material having a high work function value such as indium-tin oxide (ITO) or indium-zinc-oxide (IZO) The first electrode 147 may be formed to have a double layer structure of an upper layer made of an excellent metal material and an upper layer made of a conductive material having a high work function value or a transparent conductive material / The first electrode 147 having a triple-layer structure is formed. In the drawing, for example, the first electrode 147 has a triple-layer structure (147a, 147b, 147c).

At this time, the first electrode 147 has a concave shape toward the center in each pixel region P due to the influence of the second passivation layer 140 formed of organic insulating material located below the first electrode 147.

Next, as shown in FIG. 6K, an organic insulating material having photosensitive characteristics, for example, photo-acryl, benzocyclobutene, or polyimide is coated on the first electrode 147 to form a photosensitive organic insulating layer ).

Thereafter, an exposure mask (not shown) having a transmissive region, a blocking region and a transflective region HTA is placed on the organic insulation layer (not shown), and a diffractive exposure or halftone exposure is performed through the mask.

Thereafter, when the organic insulating layer (not shown) subjected to diffraction exposure or halftone exposure is developed, a part of the boundary of each pixel region P corresponding to the transmission region of the exposure mask (not shown) A spacer 160 is formed and a spacer 160 is formed on the boundary of each pixel region P corresponding to the transflective region of the exposure mask (not shown) so as to overlap the edge of the first electrode 147 below the spacer 160 The bank 150 is formed.

At this time, the organic insulating layer portion corresponding to the blocking region of the exposure mask (not shown) is all removed during the developing process to expose the first electrode 147 in each pixel region P, The substrate 110 for an organic EL device according to the first embodiment of the present invention is completed.

Although not shown in the figure, a shadow mask having an opening corresponding to the pixel region P corresponding to the substrate 110 for an organic EL device having the above-described structure is placed in contact with the upper portion of the spacer 160 An organic light emitting layer (not shown) is formed on the first electrode 147 in the region surrounded by the bank 150, and the organic light emitting layer (not shown) is successively formed on the organic light emitting layer (For example, aluminum, aluminum alloy, aluminum magnesium alloy, magnesium alloy, or silver) having a low work function value is deposited on the entire surface of the display region to form a second electrode (not shown). Here, the first electrode 147, the organic light emitting layer (not shown), and the second electrode (not shown) form an organic light emitting diode (not shown).

Thereafter, a counter substrate (not shown) is positioned corresponding to the substrate 101 for an organic EL device according to the first embodiment of the present invention having the above-described structure, A sealing pattern (not shown) is formed along the rim of the substrate 101 for the light emitting element and a counter substrate (not shown), and the seal pattern is formed between the substrate 101 and the counter substrate And they are joined together through a face seal to complete an organic electroluminescent device.

8A to 8C are cross-sectional views illustrating steps of manufacturing a substrate for an organic EL device according to a second embodiment of the present invention. The method of manufacturing an organic electroluminescent device substrate according to the second embodiment of the present invention is different from the method of manufacturing the substrate for an organic electroluminescent device according to the first embodiment only in the form of the exposure mask for forming the second protective layer And the method of forming the other constituent elements is the same, so the description will be given in writing.

Referring to FIG. 8A, an organic insulating layer 239 having a flat surface is formed by applying an organic insulating material having a positive type photosensitive property over the entire surface of the first passivation layer 138 or the thin film transistor DTr do.

And a blocking region BA provided on the organic insulating layer 239 and having a barrier layer BL made of a material blocking light transmission corresponding to the edge of each pixel region P, Layer film L1 having a transmissive area TA corresponding to the drain electrode 136 of the organic light-emitting diode DTr and having the same number of slits or the same number of organic or inorganic materials corresponding to other areas, (MTJ) having a transflective region (HTA) in which the transmissive amount of the transmissive region (TA) is smaller than the transmissive region (TA). At this time, the semi-transmissive area HTA is characterized in that the amount of permeation is constant and not changed for each position.

Thereafter, when the organic insulating layer 239 is exposed through the exposure mask MSK and then developed, as shown in FIG. 7B, a dam having a first height with respect to the edge of each pixel region P A drain 240 exposing the drain electrode 136 of the driving thin film transistor DTr and having a flat portion 240a having a flat surface on the inside of the dam portion 240b of each pixel region P, A second protective layer 240 having a contact hole 143 is formed.

Thereafter, as shown in FIG. 7C, the second passivation layer 240 is formed of a material having a high reflectivity / a double-layer structure of a transparent conductive material or a material having a high transparency / A first electrode 247 having a structure is formed. The first electrode 247 is formed such that the end of the first electrode 247 is positioned above the dam 240b of the second passivation layer 240 so that the first electrode 247 contacts the pixel region P And has the shape of a container having a side wall portion 246 and a flat bottom portion 248.

Thereafter, the substrate 201 for an organic EL device according to the second embodiment of the present invention can be completed by performing the same processes as those of the first embodiment.

9A to 9C are cross-sectional views illustrating steps of manufacturing a substrate for an organic EL device according to a third embodiment of the present invention. The method of manufacturing an organic electroluminescent device substrate according to the third embodiment of the present invention is different from the method of manufacturing the substrate for an organic electroluminescent device according to the first embodiment only in the form of the exposure mask for forming the second protective layer And the method of forming the other constituent elements is the same, so the description will be given in writing.

First, referring to FIG. 9A, an organic insulating layer 339 having a flat surface is formed by applying an organic insulating material having a positive type photosensitive property over the entire surface of the first passivation layer or the thin film transistor.

And a blocking region BA provided on the organic insulating layer 339 and having a barrier layer BL made of a material blocking light transmission corresponding to the edge of each pixel region P, And a plurality of slits SLT corresponding to the pixel regions P are formed in a slit shape to correspond to the drain electrodes 136 of the pixel regions DTr, A semi-transmissive region having a structure in which the slit SLT progressively denser from a central portion to an edge of the pixel, or an organic material or an inorganic material, which weakens a light transmittance, (MSK) having a semitransmissive region of a structure formed in the center portion of the region P toward the edge to a greater or greater extent.

At this time, the semi-transmissive area HTA of the exposure mask MSK is composed of a slit structure that becomes denser toward the edge from the center of the pixel area P and an organic material that weakens the light transmittance or a multi- A structure in which a greater number or a larger number of layers are formed in the center portion of the pixel region P toward the edge may be realized.

In the drawing, an exposure mask (MSK) in which a slit structure and a multilayer structure are mixed is shown as an example. In the exposure mask MSK having such a configuration, the substantially semitransmissive regions HTA1 and HTA2 are divided into a first semitransmissive region HTA1 and a second semitransmissive region HTA2, and the first semi- The slit SLT and the multilayer L2 are provided so as to have a larger amount of light transmission from the pixel region P toward the center and the second transflective region HTA2 is provided with a slit SLT (L2) structure so as to have a constant light transmission amount.

Thereafter, the organic insulating layer (339 in FIG. 9A) is exposed through the exposure mask MSK having such a shape, and then developed. When the organic insulating layer is developed, as shown in FIG. 9B, A dam portion 340b having a dam shape having a first height and a drain portion 340b having a concave shape inside the dam portion 340b of each pixel region P and exposing the drain electrode 136 of the driving thin film transistor DTr A second passivation layer 340 made of a concave portion 340a having a contact hole 143 is formed.

Then, as shown in FIG. 9C, the second passivation layer 340 may be formed of a material having a high reflectivity / a double-layer structure of a transparent conductive material or a material having a high transparency / Thereby forming a first electrode 347 having a structure. The first electrode 247 is formed at an upper portion of the dam portion 340b of the second passivation layer 340 so that the first electrode 347 covers the pixel region P, And a side surface portion 348 bent at the bottom surface portion 346. The bottom surface portion 346 has a concave bottom surface portion 346 having a concave shape.

Thereafter, the substrate for an organic electroluminescence device according to the second embodiment of the present invention can be completed by performing the same processes as those of the first embodiment.

The present invention is not limited to the above-described embodiments and modifications, and various modifications may be made without departing from the spirit of the present invention.

101: substrate for organic electroluminescence device 110: insulating substrate
111: buffer layer 113: semiconductor layer
113a and 113b: first and second regions 115: first storage electrode
116: gate insulating film 118: second storage electrode
120: gate electrode 123: interlayer insulating film
125: semiconductor layer contact hole 133: source electrode
134: third storage electrode 136: drain electrode
138: first protective layer 140: second protective layer
141: protective layer 143: drain contact hole
147: first electrode 147a: lower layer
147b: intermediate layer 147c: upper layer
150: bank 160: spacer
DA: driving region DTr: driving thin film transistor
P: pixel area StgA: storage area
StgC1, StgC2: first and second storage capacitors

Claims (20)

A substrate on which a display region having a plurality of pixel regions is defined;
A switching thin film transistor and a driving thin film transistor formed in each pixel region on the substrate;
A first protective layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor;
A first electrode formed on the first passivation layer in contact with the drain electrode of the driving TFT for each pixel region,
Wherein the first protective layer has a concave structure with a center portion for each pixel region and the first electrode also has a concave structure toward the center in each pixel region due to the influence of the first protective layer Wherein the organic light emitting device is a top emission type organic electroluminescent device substrate.
A substrate on which a display region having a plurality of pixel regions is defined;
A switching thin film transistor and a driving thin film transistor formed in each pixel region on the substrate;
A first protective layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor;
A first electrode formed on the first passivation layer in contact with the drain electrode of the driving TFT for each pixel region,
Wherein the first protective layer comprises a dam portion that surrounds the pixel region at an edge of each pixel region and a surface portion that is recessed in a central portion toward the inside of the dam portion, And the bottom of the bottom portion is bent to have a side wall and a concave shape toward the center of the substrate.
delete 3. The method according to any one of claims 1 to 2,
A bank formed on a boundary of the pixel region and overlapping an edge of the first electrode;
A spacer formed on the bank;
An organic light emitting layer formed on the first electrode inwardly of the bank;
The organic light emitting layer and the second electrode formed on the entire surface of the display region,
And a second electrode layer formed on the second electrode layer.
5. The method of claim 4,
Wherein the first electrode has a double layer structure or a triple layer structure.
6. The method of claim 5,
When the first electrode has a triple layer structure, the lower layer is made of a transparent conductive material, the intermediate layer is made of a metal material having an excellent reflectance, and the upper layer is made of a transparent conductive material having a low work function value.
Wherein the first layer is made of a metal material having a high reflectance and the second layer is made of a transparent conductive material having a low work function value when the first electrode has a double layer structure.
The method according to claim 6,
The transparent conductive material is indium-tin-oxide (ITO) or indium-zinc-oxide (IZO)
Wherein the metal material having excellent reflectivity is any one of aluminum (Al), aluminum alloy (AlNd), silver (Ag), APC (Ag, Pd, Cu alloy).
5. The method of claim 4,
Wherein the first passivation layer is made of an organic insulating material, and a second passivation layer made of an inorganic insulating material is further provided under the first passivation layer.
5. The method of claim 4,
Wherein a gate wiring and a data wiring crossing each other and defining the pixel region are formed on the substrate, and a power supply wiring arranged in parallel with the data wiring is formed, wherein the gate and the data wiring are respectively connected to the gate electrode and the source electrode Lt; / RTI >
And an opposite substrate for encapsulation facing the substrate.
Forming a switching thin film transistor and a driving thin film transistor in each pixel region on a substrate on which a display region having a plurality of pixel regions is defined;
Forming a first passivation layer covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor and having a concave structure in a center portion in each pixel region;
Forming a first electrode having a concave structure in each pixel region, the first electrode being in contact with the drain electrode of the driving thin film transistor on the first protective layer, A method for manufacturing a substrate for a device.
11. The method of claim 10,
Wherein forming the first passivation layer comprises:
Applying a photosensitive organic insulating material over the switching and driving thin film transistor to form an organic insulating layer having a flat surface;
Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask;
Developing the exposed organic insulating layer
Wherein the exposure mask has a structure in which the transflective region corresponding to each pixel region is formed in a slit shape and the slit progressively denser from a central portion to an edge of each pixel region,
Or a multilayer film composed of an organic material or an inorganic material which weakens the light transmittance is formed in a larger number or a larger thickness in the center portion of each pixel region with a different number of layers or thicknesses, Correspondingly, the blocking region is located, and the transmissive region is located corresponding to the drain electrode.
Forming a switching thin film transistor and a driving thin film transistor in each pixel region on a substrate on which a display region having a plurality of pixel regions is defined;
And a drain electrode of the driving thin film transistor covering the switching and driving thin film transistor and exposing a drain electrode of the driving thin film transistor. The edge of each pixel region surrounds the pixel region, and the surface portion is recessed toward the center of the dam portion. Forming a second protective layer on the first protective layer;
A bottom surface portion of the bottom surface portion of the driving thin film transistor is formed in a concave shape so as to be in contact with the drain electrode of each of the pixel regions over the first protective layer and located at the upper side of the dam portion in each pixel region, Forming a first electrode composed of a bent side wall portion
Wherein the organic light emitting layer is formed on the substrate.
13. The method of claim 12,
Wherein forming the first passivation layer comprises:
Applying a photosensitive organic insulating material over the switching and driving thin film transistor to form an organic insulating layer having a flat surface;
Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask;
Developing the exposed organic insulating layer
Wherein the exposure mask has a structure in which the semi-transmissive region corresponding to each pixel region is composed of a multilayer film made of an organic material or an inorganic material that weakens the light transmittance, And the transmissive region is located corresponding to the drain electrode.
delete 13. The method of claim 12,
The step of forming the first passivation layer, the surface of which is concave,
Applying a photosensitive organic insulating material over the switching and driving thin film transistor to form an organic insulating layer having a flat surface;
Placing an exposure mask having a light transmission region, a blocking region and a transflective region on the organic insulation layer, and then exposing the organic insulation layer through the exposure mask;
Developing the exposed organic insulating layer
Wherein the exposure mask has a blocking region having a blocking layer made of a material blocking light transmission and a transmissive region corresponding to a drain electrode of the driving thin film transistor,
A plurality of slits corresponding to the pixel regions are formed in a slit shape, and a semi-transmissive region having a structure in which the slits are progressively denser from a central portion to an edge of each pixel region,
Or a semi-transmissive region having a structure in which the number of layers made of an organic material or an inorganic material that weakens the light transmittance is increased or increased in thickness from the central portion to the edge of the pixel region,
Or a slit structure that becomes denser toward the edge from the central portion of each pixel region and a semi-transmissive region in which the multi-layer structure for weakening the light transmittance is formed in a larger or thicker structure as the edge portions of the respective pixel regions are more Wherein the substrate is an organic electroluminescent device.
13. A method according to any one of claims 10 and 12,
Forming a bank at a boundary of the pixel region and overlapping an edge of the first electrode;
Forming spacers on top of the banks;
Forming an organic light emitting layer on the first electrode inside the bank;
Forming an organic light emitting layer and a second electrode on the entire surface of the display region above the bank
Wherein the organic light emitting layer is formed on the substrate.
17. The method of claim 16,
Wherein the first electrode is formed to have a double layer structure or a triple layer structure.
18. The method of claim 17,
When the first electrode has a triple layer structure, a first transparent conductive material layer, a reflective layer made of a metal material having excellent reflectivity and a second transparent conductive material layer are sequentially formed on the first protective layer, Forming a first electrode having a triple layer structure by patterning a transparent conductive material layer, a reflective layer, and a first transparent conductive material layer,
When the first electrode has a double layer structure, a reflective layer made of a metal material having excellent reflectivity and a transparent conductive material layer are sequentially formed, and the reflective layer and the transparent conductive material layer are patterned to form the first electrode having the double layer structure Wherein the organic electroluminescent device is a substrate.
17. The method of claim 16,
Wherein a second passivation layer made of an inorganic insulating material is further formed on the switching and driving thin film transistor before forming the first passivation layer.
17. The method of claim 16,
Wherein the step of forming the switching and driving thin film transistors includes forming gate wirings and data wirings intersecting with each other to define the pixel region and power supply wirings arranged in parallel with the data wirings, And the wirings are formed to be connected to the gate electrode and the source electrode of the switching thin film transistor, respectively.

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