KR20130007872A - Array substrate for organic electro luminescent device and method of fabricating the same - Google Patents

Abstract

PURPOSE: An array substrate for an organic electro luminescent device and a method for fabricating the same are provided to prevent light from leaking out of a first electrode and to improve reflection efficiency. CONSTITUTION: A substrate has a displaying area. The displaying area has multiple pixel regions. A switching thin film transistor and a driving thin film transistor are formed in each pixel region. A first protection layer(138) covers the switching and driving thin film transistor. A first electrode(147) touches the drain electrode(136).

Description

Array substrate for organic electroluminescent device and method of fabricating the same}

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 an organic electroluminescent device having a thin film transistor including polysilicon as a semiconductor layer and capable of improving light efficiency and suppressing leakage current. A substrate 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, the manufacturing process of the organic light emitting device is very simple because the deposition (deposition) and encapsulation (encapsulation) equipment is all.

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. Such an organic light emitting device 1 is manufactured in a top emission method for displaying an image using light emitted toward the second electrode 58 in consideration of an aperture ratio and the like.

Looking at the path of light in the conventional organic light emitting device 1 having such a configuration, the voltage is applied to the first and second electrodes 47 and 58, the electrons and holes are supplied to the organic light emitting layer 55 Light is generated by recombination in the organic light emitting layer 55.

The light emitted from 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 sun is released to the outside, and the light exiting through the surface of the counter substrate 70 is incident to the user's eyes, so that the user can watch the image.

However, light generated in the organic light emitting layer 55 passes through components positioned above and below the organic light emitting layer 55, and loss is generated therein, so that light incident to the eyes of the user is substantially emitted to the organic light emitting layer 55. ) Is about 19% of the light generated by the situation.

In more detail, the top emission type organic light emitting diode 1 is formed to implement a micro cavity effect to improve light emission characteristics. That is, the first electrode 47 is formed to have a structure of two or more layers having the same shape in planarity by continuously depositing and simultaneously patterning heterogeneous metal materials or transparent conductive materials, and the second electrode 58 is also made of a reflective material. It is configured to reflect between the first electrode 47 and the second electrode 58 by forming.

However, in the conventional top emission type organic light emitting device 1 having such a configuration, light disappearing through the side surface of the first electrode 47 due to total reflection inside thereof is particularly due to the structural characteristics of the first electrode 47. Many problems arise that the reflection efficiency is lowered.

The present invention has been made to solve the above problems, the present invention is a top light emitting method that can improve the reflection efficiency by minimizing the light disappearing inside the first electrode in the organic light emitting device substrate of the top emission method It is an object to provide a substrate for an organic light emitting device.

According to an aspect of the present invention, there is provided a substrate for an organic light emitting display device, including: a substrate having a display area having a plurality of pixel areas defined therein; A switching thin film transistor and a driving thin film transistor formed in each pixel area on the substrate; A first passivation 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 thin film transistor for each pixel region, wherein the first passivation layer has a concave structure toward the center of each pixel region. The first electrode also has a concave structure toward the center portion of each pixel area due to the influence of the first protective layer.

In addition, the organic light emitting device substrate according to another embodiment of the present invention includes a substrate having a display area having a plurality of pixel areas defined; A switching thin film transistor and a driving thin film transistor formed in each pixel area on the substrate; A first passivation 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 thin film transistor for each pixel region, wherein the first passivation layer surrounds the pixel region at an edge of each pixel region. And a surface portion inside the dam portion, and the first electrode has a shape in which an end portion thereof is bent to form a side wall in the pixel region by the end portion thereof being positioned on an upper surface of the dam portion. In this case, the first passivation layer has a flat surface portion or a concave shape toward the center portion of each pixel area, and the first electrode also has a bottom portion overlapping the surface portion of the first passivation layer. It is characterized by forming a flat shape or concave toward the center of each pixel area.

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

When the first electrode has a double layer or triple layer structure, when the first electrode has a triple layer structure, the lower layer is made of a transparent conductive material, the middle layer is made of a metal material having excellent reflectance, and the upper layer is a work function. Characterized in that the lower value of the transparent conductive material, when the first electrode has a double layer structure, the first layer is made of a metal material with excellent reflectance, the second layer is made of a transparent conductive material having a low work function value Is characteristic.

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

The first passivation layer may be made of an organic insulating material, and a second passivation layer made of an inorganic insulating material may be further provided below the first passivation layer.

A gate line and a data line crossing the substrate to define the pixel region, and a power line disposed to be parallel to the data line, wherein the gate and the data line are respectively a gate electrode and a source electrode of the switching thin film transistor. It is connected to the, characterized in that the opposite substrate for the encapsulation facing the substrate is provided.

A method of manufacturing a substrate for an organic light emitting device according to an embodiment of the present invention comprises the steps of: forming a switching thin film transistor and a driving thin film transistor in each pixel area on a substrate on which a display area having a plurality of pixel areas 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, the first protective layer having a concave structure toward the center of each pixel region; Forming a first electrode on the first passivation layer in contact with the drain electrode of the driving thin film transistor for each pixel region and having a concave structure in the pixel region for each pixel region.

The forming of the first protective layer may include forming an organic insulating layer having a flat surface by applying a photosensitive organic insulating material onto the switching and driving thin film transistor; Placing an exposure mask including a light transmitting region, a blocking region, and a semi-transmissive region over the organic insulating layer, and then exposing the organic insulating layer through the exposure mask; And developing the exposed organic insulating layer, wherein the exposure mask includes the semi-transmissive area corresponding to each pixel area having a slit shape, and the slit gradually progresses toward the edge from the center of each pixel area. A multi-layered film made of an organic material or an inorganic material that forms a dense structure or weakens the transmittance of light, and has a structure in which the number of layers or the thickness is increased so as to become more or thicker from the center of each pixel area to the edge. The blocking region is positioned to correspond to the boundary of each pixel region, and the transmission region is positioned to correspond to the drain electrode.

According to still another aspect of the present invention, there is provided a method of manufacturing a substrate for an organic light emitting diode, including: forming a switching thin film transistor and a driving thin film transistor in each pixel area on a substrate on which a display area having a plurality of pixel areas is defined; ; A drain portion covering the switching and driving thin film transistors and exposing the drain electrodes of the driving thin film transistors, the dam portion having a shape surrounding the pixel regions at an edge of each pixel region, and a first protective layer having a surface portion inside the dam portion; Making a step; Contacting the drain electrode of the driving thin film transistor for each pixel region on the first passivation layer and positioned at an upper side of the dam portion at each end of the pixel region to form a first electrode including a bottom portion and a bent sidewall portion; Steps.

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

The surface portion of the first passivation layer may be flat in each pixel area, or may be concave toward the center of each pixel area.

The forming of the first protective layer having the concave shape of the surface portion may include forming an organic insulating layer having a flat surface by coating a photosensitive organic insulating material on the switching and driving thin film transistor; Placing an exposure mask including a light transmitting region, a blocking region, and a semi-transmissive region over the organic insulating layer, and then exposing the organic insulating layer through the exposure mask; And developing the exposed organic insulating layer, wherein the exposure mask includes a blocking region having a blocking layer made of a material that blocks light transmission, and a transmission region corresponding to the drain electrode of the driving thin film transistor. And a plurality of slits corresponding to each pixel area to form a slit, and have a semi-transmissive area forming a structure in which the slits gradually become denser from the center portion of each pixel area to an edge, or Multilayers made of organic or inorganic materials that weaken the transmittance of light have a semi-transmissive region having a structure in which the number of layers or the thickness of the multilayer increases from the central portion of each pixel region to the edges, or The slit structure and the light transmittance that are densified toward the edge from the center of each pixel area 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 overlapping an edge of the first electrode and bordering the pixel region; Forming a spacer on the bank; Forming an organic emission layer on the first electrode in the bank; And forming a second electrode over the display area over the organic emission layer and the bank.

In this case, the first electrode may be formed to form a double layer or triple layer structure, and when the first electrode has a triple layer structure, the first transparent conductive material layer and the metal having excellent reflectivity above the first protective layer. Forming a reflective layer made of a material and a second transparent conductive material layer sequentially, and patterning the second transparent conductive material layer, the reflective layer and the first transparent conductive material layer to form a first electrode forming the triple layer structure, and 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 first electrode having the double layer structure is formed by patterning the reflective layer and the transparent conductive material layer. Is characteristic.

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

The forming of the switching and driving thin film transistor may include forming a gate line and a data line crossing each other to define the pixel area, and a power line disposed to be parallel to the data line. And data lines are formed to be connected to the gate electrode and the source electrode of the switching thin film transistor, respectively.

In the substrate for an organic light emitting device according to an embodiment of the present invention, the protective layer in which the first electrode serving as the anode electrode is positioned has a concave shape for each pixel region, so that the first electrode has a concave mirror shape. The first electrode is formed such that the passivation layer is formed to have a dip shape adjacent to the boundary of each pixel region for each pixel region so that the first electrode is bent at both ends in each pixel region. By minimizing the light leaking to the side has the effect of improving the light efficiency.

1 is a cross-sectional view of one pixel area of a conventional organic light emitting display device.
2 is a circuit diagram of one pixel of a general organic light emitting diode.
3 is a cross-sectional view of one pixel area of a substrate for an organic light emitting display device according to a first embodiment of the present invention.
4 is a cross-sectional view of one pixel area of a substrate for an organic light emitting display device according to a second embodiment of the present invention.
5 is a cross-sectional view of one pixel area of a substrate for an organic light emitting display device according to a third embodiment of the present invention.
6A to 6K are cross-sectional views illustrating manufacturing steps of one pixel area of a substrate for an organic light emitting diode according to a first exemplary embodiment of the present invention.
FIG. 7 is a view illustrating a step of forming a second protective layer during the manufacturing step of the substrate for an organic light emitting device according to the first embodiment of the present invention. FIG.
8A through 8C are cross-sectional views illustrating manufacturing steps of one pixel area of a substrate for an organic light emitting diode according to a second exemplary embodiment of the present invention.
9A to 9C are cross-sectional views illustrating manufacturing steps of one pixel area of a substrate for an organic light emitting diode according to a third exemplary embodiment of the present invention.

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 illustrated, one pixel area of the organic light emitting diode is provided with a switching thin film transistor STr, a driving thin film transistor DTr, a storage capacitor StgC, and an organic light emitting diode E. It is becoming.

That is, the gate line GL is formed in the first direction, the pixel region P is defined in the second direction crossing the first direction, and the data line DL is formed. And a power supply wiring (PL) for applying a power supply voltage is spaced apart.

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 area of a substrate for an organic light emitting display device according to a first embodiment of the present invention. In this case, for convenience of description, the region in which the driving thin film transistor DTr is formed is the driving region DA, and the region in which the switching thin film transistor is formed in each pixel region P is not shown in the figure. And, the area where the storage capacitor is formed is defined as a storage area StgA.

As shown in the substrate 101 for the organic light emitting device according to the present invention, each of the driving area DA and the switching area (not shown) on the insulating substrate 110 forming a base is made of pure polysilicon. The semiconductor layer 113 includes a first region 113a constituting a channel passage and a second region 113b doped with a high concentration of impurities on both sides of the first region 113a.

In addition, a first storage electrode 115 made of polysilicon doped with impurities is formed in each storage region StgA.

In this case, between the semiconductor layer 113, the first storage electrode 115, and the insulating substrate 110, an inorganic insulating material, for example, silicon oxide (SiO ₂ ) or silicon nitride ( A buffer layer (not shown) made of SiNx may be further provided.

The buffer layer (not shown) is the semiconductor layer 113 due to the release of alkali ions emitted from the inside of the first substrate 110 during crystallization of the semiconductor layer 113 and the first storage electrode 115 made of polysilicon. This is to prevent the deterioration of the characteristics.

A gate insulating layer 116 is formed on the entire surface of the polysilicon semiconductor layer 113 and the first storage electrode 115, and the driving area DA and the switching area (not shown) are disposed on the gate insulating layer 116. The gate electrode 120 is formed in each of the semiconductor layers 113 to correspond to the first region 113a.

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).

In the storage region StgA, a second storage electrode 118 made of the same metal material that forms the gate wiring in response to the first storage electrode 115 made of polysilicon doped with impurities on the gate insulating layer 116. ) Is formed. In this case, the first storage electrode 115, the gate insulating layer 116, and the second storage electrode 118 sequentially stacked in the storage region StgA form a first storage capacitor StgC1.

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

In this case, the interlayer insulating layer 123 and the gate insulating layer 116 below the semiconductor layer contact hole exposing the second region 113b located on both sides of the first region 113a corresponding to each semiconductor layer. 125) is provided.

Next, a data line (not shown) defining the pixel region P is formed on the interlayer insulating layer 123 provided with the semiconductor layer contact hole 125 to cross the gate line (not shown). Power lines (not shown) are formed to be spaced apart from the data lines (not shown).

In addition, a second region of each of the semiconductor layers 113 exposed through each of the semiconductor layer contact holes 125 and spaced apart from each other in the driving region DA and the switching region (not shown) is disposed on the interlayer insulating layer 123. The source electrode and the drain electrodes 133 and 136 are formed in contact with and spaced apart from each other and in contact with 113b).

The source and drain electrodes 133 and 136 spaced apart from the semiconductor layer 113, the gate insulating layer 116, the gate electrode 120, and the interlayer insulating layer 123 sequentially stacked in the driving region DA may be formed. A driving thin film transistor DTr is formed. In this case, a switching thin film transistor (not shown) having the same structure as the driving thin film transistor DTr formed in the driving area DA is also formed in the switching area (not shown).

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

On the other hand, the source electrode 133 of the driving thin film transistor DTr extends to the storage region StgA, and overlaps the second storage electrode 118 with the interlayer insulating layer 123 interposed therebetween, and thus, the third storage device. The electrode 134 is formed. In this case, the second storage electrode 118, the interlayer insulating film 123, and the third storage electrode 134 overlapping each other form a second storage capacitor StgC2, and the first and the first and second storage electrodes StgA are formed. The second storage capacitors StgC1 and StgC2 form a structure in which the second storage electrodes 118 are connected in parallel to each other through the second storage electrode 118, thereby increasing the total storage capacitor capacity.

Meanwhile, the driving and switching thin film transistor DTr (not shown) may form a p-type or n-type thin film transistor according to impurities doped in the second region 113b. In the case of a p-type thin film transistor, a third group element, for example, boron (B), is doped in the second region 113b. In the case of an n-type thin film transistor, a group 5 is formed in the second region 113b. This is done by doping an element, for example phosphorus (P).

The p-type thin film transistor uses holes as a carrier, and the n-type thin film transistor uses electrons as a carrier.

Therefore, the first electrode 147 connected to the drain electrode 136 of the driving thin film transistor DTr serves as an anode or a cathode according to 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 n type, the first electrode 147 serves as a cathode electrode.

In the first exemplary embodiment of the present invention, the driving thin film transistor DTr forms the p-type, and thus, the first electrode 147 serves as an anode.

Next, a passivation layer having a drain contact hole 143 exposing the drain electrode 136 of the driving thin film transistor DTr over the driving and switching thin film transistor DTr (not shown) and the second storage capacitor StgC2. 141 is formed. In this case, in the first embodiment of the present invention, the protective layer 141 forms a double layer structure of a first protective layer 138 made of an inorganic insulating material and a second protective layer 140 made of an organic insulating material thereon. Although illustrated as an example, the protective layer 141 may be formed as a single layer structure made of an organic insulating material.

The protective layer 141 is formed in a double layer structure of the first protective layer 138 made of an inorganic film and the second protective layer 140 made of an organic film for improving bonding properties and process stabilization. This is because the bonding strength between the inorganic material and the metal material and the bonding strength between the inorganic material and the organic material are superior to those between the organic material and the metal material.

In this case, the second protective layer 140 is the most characteristic in the first embodiment of the present invention. The surface of the second protective layer 140 corresponds to each pixel region P. The surface of the second protective layer 140 is more precisely the center portion of each pixel region P. It is characterized in that the center portion is concave in the pixel area P with a thickness thinner than the side surface.

Next, the drain electrode 136 and the drain contact hole 143 of the driving thin film transistor DTr are disposed on the second passivation layer 140 having a concave shape toward the center in each pixel area P. In contact with each other, a first electrode 147 is formed for each pixel region P. FIG. In this case, the first electrode 147 has a triple layer or a double layer structure. Furthermore, the first electrode 147 has a concave shape toward the center portion of each pixel area P due to the influence of the second protective layer 140. It is characteristic.

Looking at the structure of the first electrode 147, in the case of forming a triple layer having a triple layer structure of the lower layer 147a, the intermediate layer 147b, and the upper layer 147c, the lower layer 147a is a transparent conductive material such as indium. Tin-oxide (ITO) or indium-zinc-oxide (IZO), and the intermediate layer 147b disposed on the lower layer 147a is a metal material having excellent reflectivity, for example, aluminum alloy (AlNd), It is made of one of silver (Ag) and APC (Ag, Pd, Cu alloy), and the upper layer 147c positioned above the intermediate layer 147b is a transparent conductive material having a high work function value, for example, indium-tin-. It is configured to serve as an anode electrode by being formed as an oxide (ITO).

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

Although not shown in the drawing, the first electrode 147 is made of indium tin oxide having a relatively high work function value to serve as an anode electrode and a first layer made of a metal having excellent reflectance. It may also be formed to have a second layer made up.

Meanwhile, as described above, the first electrode 147 is formed in a double layer or a triple layer to form a concave shape from the pixel area P toward the center part. Thus, the first electrode 147 is formed in each pixel area P. As shown in FIG. In the concave mirror.

Therefore, when light generated from an organic light emitting layer (not shown) positioned above the first electrode 147 is incident on the first electrode 147, it is further compared with the first electrode 147 having a conventional planar shape. It is possible to efficiently reflect upward, and some of the light exiting the side surface of the organic light emitting device substrate 101 by total reflection in the first electrode 147 itself affects the bending of the first electrode 147 itself. It is characterized by being a configuration to suppress a considerable amount to improve the light efficiency.

Next, a bank 150 is formed on the first electrode 147 having the above-described shape and overlaps an edge of the first electrode 147 and is formed on the boundary of each pixel region P on the passivation layer 140. have.

Spacers 160 are spaced apart from the bank 150 by a predetermined interval.

Although not shown in the drawings, an organic emission layer (not shown) is formed on the first electrode 147 inside each pixel region P surrounded by the bank 150.

In this case, the organic light emitting layer (not shown) may be composed of a single layer made of an organic light emitting material, or from the surface of the upper layer 147c of the first electrode 147 acting as the anode electrode to increase the luminous efficiency. Sequentially, the hole injection layer 155a, the hole transport layer, the hole transporting layer, the organic light emitting material layer, the electron transporting layer and the electron injection layer It may be formed to have a layer structure.

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

In this case, the second electrode (not shown) is a metal material having a low work function value to serve as a cathode electrode, for example, silver (Ag), magnesium-silver alloy (MgAg), gold (Au), magnesium ( Mg), copper (Cu), calcium (Ca) may be formed to have a thickness of about 50 ~ 200 ~, or any one of the lower layer is made of a metal material having a relatively low work function value, as described above, An upper layer made of any one of an indium-ink-oxide (ITO) or an indium-tin-oxide (ITO), which is a transparent conductive material, may be further provided to have a double layer structure.

The second electrode (not shown) is formed to have a double layer structure in order to reduce the sheet resistance of the second electrode (not shown) itself.

The second electrode (not shown) should be formed of a metal material having a low work function value to serve as a cathode electrode due to the characteristics of the organic light emitting device of the upper emission type. If the thickness is too thick, the second electrode (not shown) has a low transparency and is required as a display device. It is difficult to express the characteristics, and if the second electrode is formed to a thin thickness for this purpose, since the sheet resistance is increased, the driving voltage is increased and the power consumption is increased, thereby forming an upper layer made of a transparent conductive material.

In this case, the first electrode 147, the organic light emitting layer (not shown), and the second electrode (not shown) sequentially stacked in each pixel area P form an organic light emitting diode (not shown).

Opposite substrates (not shown) for encapsulation are spaced apart from each other to correspond to the substrate 101 for an organic light emitting device according to the first embodiment of the present invention including the components described above. At this time, the organic light emitting device substrate 101 and the counter substrate (not shown) are provided with an adhesive (not shown) made of a sealant or frit along its edge, and the organic substrate is bonded by such an adhesive (not shown) Electroluminescent element is formed.

In this case, the organic light emitting device substrate 101 and the opposing substrate (not shown) spaced apart from each other have a vacuum atmosphere or are filled with an inert gas to form an inert gas atmosphere.

The opposing substrate (not shown) for the encapsulation may be made of a plastic having a flexible characteristic, or may be made of a glass substrate, and further, the opposing substrate (not shown) is adhesive in the form of a film including an adhesive layer. It may be configured to contact the second electrode (not shown) provided in the uppermost layer of the substrate 101 for the organic light emitting device via a layer.

In the substrate 101 for the organic light emitting diode having the above-described configuration, the first electrode 147 has a concave mirror shape toward the center of each pixel region P, so that light emitted from the organic light emitting layer (not shown) is raised. It is possible to increase the reflection efficiency reflected to the side, and the effect of improving the light efficiency by suppressing some of the light that is totally reflected inside the first electrode 147 and exits to the side by the concave shape of the first electrode 147 itself. It is characterized by having.

4 is a cross-sectional view of one pixel area of a substrate for an top emission type organic light emitting diode according to a second exemplary embodiment of the present invention. In this case, in the case of 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 that of the first embodiment, so only the protective layer and the first electrode having the difference point will be described. do. In this case, the same reference numerals are assigned to the same components as those in the first embodiment for convenience of description.

The second protective layer 240 made of the organic insulating material formed on the substrate 201 of the top emission type organic light emitting diode according to the second embodiment of the present invention has a flat surface at its center in each pixel region P. FIG. And a dam portion 240b having a dam shape along the edges of the planar portion 240a and the pixel areas P.

Next, the first electrode 247 is formed on the second passivation layer 240 having the above-described configuration by contacting the drain electrode 136 of the driving thin film transistor DTr for each pixel region P. Referring to FIG. At this time, the end of the first electrode 247 is formed to extend to the upper surface of the dam portion 240b of the second protective layer 240 is characterized in that the cross-sectional shape as if it is a recessed container form.

That is, the first electrode 147 provided in each pixel region P surrounds a bottom portion 246 having a flat surface and the bottom portion 246 and bent at an edge thereof to form a sidewall. 248).

Therefore, the first electrode 247 having such a shape increases the reflectance of light incident toward the first electrode 247 in the organic light emitting layer (not shown) formed on the side surface 248. In addition, since the light itself has a bent portion, the light emitted from the side surface due to total reflection inside the first electrode 247 is suppressed to have an effect of improving 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 light emitting device according to the first embodiment, and thus description thereof is omitted.

5 is a cross-sectional view of one pixel area P of the substrate for the top emission type organic light emitting diode according to the third exemplary embodiment of the present invention. At this time, in the case of the third embodiment of the present invention, most of the components are the same, and only the second protective layer and the first electrode have a different form from that of the first embodiment, so that the second protective layer and the first protective layer having different points Only the electrode will be described. In this case, the same reference numerals are assigned to the same components as those in the first embodiment for convenience of description.

The organic light emitting diode substrate 301 according to the third embodiment of the present invention is provided on the organic light emitting diode substrates 301 of FIG. 3 and 301 of FIG. 4 according to the first and second embodiments of the present invention. The second protective layer (140 in Fig. 3, 240 in Fig. 4) and the first electrode (147 in Fig. 3, 247 in Fig. 4) are characterized as being combined.

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

In addition, the first electrode 347 provided in each pixel area P on the second protective layer 340 having the above shape may be formed at the edge of the bottom portion 346 and the bottom portion 346 having a concave shape. The side portion 348 is bent along the dam portion 340b of the second protective layer 340 and is formed on the side of the dam portion 340.

In the case of the second protective layer 340 having the above 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 according to the first and second embodiments according to the first and second embodiments by the bent portion provided on the first electrode 347 itself and the bottom portion 346 is concavely bent to the light that is totally reflected in the interior toward the side Since it can suppress more efficiently than (147 of FIG. 3, 247 of FIG. 4), it becomes the structure which can improve the light efficiency most.

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

6A to 6K are cross-sectional views illustrating manufacturing steps of one pixel region P of the substrate for an organic light emitting diode according to the first embodiment of the present invention. For convenience of description, a region in which the thin film transistor is formed in each pixel region P is defined as an element region DA and a region in which a storage capacitor is formed as a storage region StgA, and is formed in the element region DA. The thin film transistor is a driving thin film transistor DTr connected to an organic light emitting diode, and the 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 did not show as it had.

First, as illustrated in FIG. 6A, a buffer layer 111 is formed by depositing silicon nitride (SiNx) or silicon oxide (SiO ₂ ), which is an inorganic insulating material, on the insulating substrate 110. In the buffer layer 111, when the amorphous silicon layer is recrystallized from the polysilicon layer, alkali ions, for example, potassium ions (K +), present in the insulating substrate 110 due to heat generated by laser irradiation or heat treatment. ), Sodium ions (Na +), etc. may be generated to prevent the film properties of the semiconductor layer made of polysilicon from being deteriorated by the alkali ions. In this case, the buffer layer 111 may be omitted depending on the material of the substrate 110.

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. In this case, it is preferable that the crystallization process is a crystallization process using solid phase crystallization (SPC) or a laser.

The solid phase crystallization (SPC) process, for example, thermal crystallization (Thermal Crystallization) through heat treatment in an atmosphere of 600 ℃ to 800 ℃ or alternating magnetic field crystallization (Alternating Magnetic in a temperature atmosphere of 600 ℃ to 700 ℃ using an alternating magnetic field crystallization device It is preferable that the field crystallization process, and the crystallization using the laser is preferably an Excimer Laser Annealing (ELA) method or a sequential lateral solidification (SLS) crystallization using an excimer laser.

Next, as illustrated in FIG. 6B, a mask process including applying the polysilicon layer (180 of FIG. 6A) to photoresist, exposing using an exposure mask, developing exposed photoresist, etching, and stripping is performed. By proceeding and patterning, a polysilicon semiconductor layer 113 is formed in the device region DA, and a polysilicon semiconductor pattern 114 is formed in the storage region StgA. In this case, the semiconductor pattern 114 may form a first storage electrode (115 of FIG. 6C) after the dopant is later doped to improve conductivity.

Next, as shown in FIG. 6C, an inorganic insulating material such as silicon nitride (SiNx) or silicon oxide (SiO ₂ ) is deposited on the entire surface of the semiconductor pattern 114 and the semiconductor layer 113 of polysilicon. The insulating film 116 is formed.

Thereafter, a photoresist layer (not shown) is formed on the gate insulating layer 116 and patterned to form a photoresist pattern 190 corresponding to the driving area DA.

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

Next, as shown in FIG. 6D, the gate insulating layer 116 is exposed by removing the photoresist pattern (190 of FIG. 6C) through a strip.

Subsequently, a low resistance metal material on the entire surface of the gate insulating layer 116, for example, aluminum (Al), aluminum alloy (AlNd), copper (Cu), copper alloy, molybdenum (Mo), or molybdenum (MoTi) Alternatively, two or more materials may be deposited to form a gate metal layer (not shown) of a single layer or multilayer structure.

Next, the gate metal layer (not shown) is patterned through a mask process to form a gate wiring (not shown) extending in one direction at the boundary of the pixel region P, and at the same time, the poly The gate electrode 120 is formed to correspond to the central portion of the semiconductor layer 113 of silicon, and the second storage electrode 118 is formed in the storage region StgA. In this case, the first storage electrode 115, the gate insulating layer 116, and the second storage electrode 118 sequentially stacked in the storage region StgA form a first storage capacitor StgC1.

Next, as illustrated in FIG. 6E, the polysilicon layer of the polysilicon layer may be doped with the n-type impurity or the p-type impurity to the semiconductor layer 113 of the polysilicon using the gate electrode 120 as a doping mask. An ohmic contact layer 113b doped with impurities is formed on both sides of the central portion of the substrate 113. In this case, the semiconductor layer 113 region of polysilicon that is not doped by 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 (SiNx), which is an inorganic insulating material, is disposed on the entire surface of the gate electrode 120, the gate wiring (not shown), and the second storage electrode 118. Is deposited, or benzocyclobutene (BCB) or photo acryl, which is an organic insulating material, is coated to form an interlayer insulating film 123.

Subsequently, a mask process is performed on the interlayer insulating layer 123 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, respectively. The semiconductor layer contact hole 125 is formed.

Next, as shown in FIG. 6G, a metal material such as aluminum (Al), aluminum alloy (AlNd), copper (Cu), and copper on the front surface of the interlayer insulating layer 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 an alloy, molybdenum (Mo), and molybdenum (MoTi).

Subsequently, the second metal layer (not shown) is patterned by a mask process so as to cross the gate line (not shown) at the boundary of the pixel area P to define a data line (not shown). At the same time, power lines (not shown) are formed in parallel with the data lines (not shown).

At the same time, source and drain electrodes 133 and 136 are formed in the device area DA to contact the ohmic contact layer 113b and to be spaced apart from each other through the semiconductor layer contact hole 125. In this case, the drain electrode 136 is formed to extend to the storage region StgA to form the third storage electrode 134.

In this configuration, the second storage electrode 118, the interlayer insulating layer 123, and the third storage electrode 134 form a second storage capacitor StgC2 in the storage region StgA. The second storage capacitors StgC1 and StgC2 have a structure in which the second storage electrodes 118 are connected in parallel to each other through the second storage electrode 118, thereby increasing the total storage capacitor capacity.

Next, as shown in FIG. 6H, an example of an inorganic insulating material is formed on the front surface of the source and drain electrodes 133 and 136, the data line (not shown), the power line (not shown), and the third storage electrode 134. For example, silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is deposited to form a first passivation layer 138, and subsequently, benzocyclobutene (BCB) or a photoresist, which is an organic insulating material, is formed on the first passivation layer 138. Photoacryl is applied to overcome the steps of the underlying components to form a second protective layer 140 having a flat surface. At this time, the second protective layer 140 is characterized in that it has a positive type photosensitive characteristic having a characteristic that is removed during development when receiving light.

The first passivation layer 138 made of the inorganic insulating material may be omitted. In the case of forming the first passivation layer 138, the driving thin film is formed by first patterning the mask by forming a mask on the first passivation layer 138. The primary drain contact hole 139 exposing the drain electrode of the transistor DTr is formed.

Next, the transmission area of the light is smaller than the blocking area BA, the transmission area TA, and the transmission area TA corresponding to each pixel area P on the second passivation layer 140. An exposure mask MSK having a transflective area HTA having a light transmission amount of 10% to 90% of the light transmission amount of (TA) is positioned.

In this case, the transmission area TA corresponds to the drain electrode 136 of the thin film transistor DTr, and the blocking area BA corresponds to the boundary of each pixel area P, and each pixel area P corresponds to the drain electrode 136 of the thin film transistor DTr. The exposure mask MSK is positioned so that the transflective area HTA corresponds to the opening of the aperture.

 On the other hand, the exposure mask MSK has a semi-transmissive area (HTA) corresponding to each pixel area (P) as shown in the form of a slit, the slit toward the edge from the center of the pixel area (P) It becomes a progressively dense structure, or is shown in Fig. 7 (Fig. 7 shows the step of forming a second protective layer during the manufacturing step of the substrate for an organic light emitting device according to the first embodiment of the present invention) As described above, the multilayer films L1, L2, and L3 made of organic or inorganic materials, which weaken the transmittance of light, are formed in a greater number or thicker from the central portion of the pixel region P to the edges by varying the number or thickness of layers. It is characterized by forming a structure.

Therefore, when the second protective layer 140 is exposed to light using an exposure mask MSK having such a structure, and a development process is performed on the second protective layer 140, as shown in FIG. 6J, a blocking region (BA of FIG. 6I) is shown. The second protective layer 140 forms a flat surface and is formed as it is without any change in thickness at a portion where light is blocked, that is, at a boundary portion of each pixel region P, and the transflective region (HTA of FIG. 6I). Since the portion corresponding to is exposed to more light toward the center portion, the thickness gradually decreases toward the center portion of each pixel region P to form a concave shape, and the drain electrode 136 of each driving thin film transistor DTr. ), A drain contact hole 143 exposing the drain electrode 136 is formed.

When the first passivation layer 138 is formed, the drain is formed in the second passivation layer 140 to pass through the primary drain contact hole (139 in FIG. 6I) provided in the first passivation layer 138. The contact hole 143 is formed.

Next, a transparent conductive material having a high work function value on the entire surface of the drain contact hole 143 and the second protective layer 140 having a concave shape corresponding to each pixel region P, for example, indium-tin-oxide ( ITO) or indium-zinc-oxide (IZO) is deposited on the entire surface, and patterned by a mask process, thereby forming a first electrode 147 contacting the drain electrode 136 through the drain contact hole 143. .

At this time, in order to increase the luminous efficiency of the organic light emitting diode (not shown) before depositing the transparent conductive material on the second protective layer 140, a metal material having excellent reflectivity, for example, aluminum (Al), aluminum alloy (AlNd) ) And silver (Ag) first, and then a transparent conductive material having a high work function value, for example, indium tin oxide (ITO) or indium zinc oxide (IZO), by depositing and patterning. The first electrode 147 is formed to have a double layer structure of a lower layer (not shown) 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 / excellent reflective material / transparent conductive material A first electrode 147 having a triple layer structure of is formed. In the drawing, for example, the first electrode 147 has a triple layer 147a, 147b, and 147c structure as an example.

In this case, the first electrode 147 is formed to be concave toward the center portion of each pixel area P under the influence of the second protective layer 140 made of an organic insulating material disposed under the first electrode 147.

Next, as shown in FIG. 6K, an organic insulating material having photosensitive characteristics, for example, photoacryl, benzocyclobutene, or polyimide, is coated on the first electrode 147 to form a photosensitive organic insulating layer (not shown). C).

Thereafter, an exposure mask (not shown) having a transmission region, a blocking region, and a transflective region (HTA) is positioned on the organic insulating layer (not shown), and diffraction exposure or halftone exposure is performed through the exposure mask.

Subsequently, when the organic insulating layer (not shown) is subjected to diffraction exposure or halftone exposure, a portion of the boundary of each pixel region P corresponding to the transmission region of the exposure mask (not shown) has a first height. A spacer 160 is formed and overlaps an edge of the first electrode 147 below the spacer 160 at a boundary of each pixel region P corresponding to the transflective region of the exposure mask (not shown). Bank 150 is formed.

In this case, the portion of the organic insulating layer corresponding to the blocking region of the exposure mask (not shown) may be removed during the development process to expose the first electrode 147 in the pixel region P. FIG. The substrate 110 for an organic light emitting device according to the first embodiment of the present invention is completed.

Although not shown in the drawings, the shadow mask having an opening corresponding to the pixel region P in contact with the upper portion of the spacer 160 corresponds to the pixel region P, which is configured to have the above-described structure. After performing vacuum thermal evaporation, an organic light emitting layer (not shown) is formed on the first electrode 147 in the region surrounded by the bank 150, and the entire display area is successively disposed above the organic light emitting layer (not shown). A metal material having a low work function value, for example, aluminum, an aluminum alloy, an aluminum magnesium alloy, a magnesium silver alloy, or silver is deposited to form a second electrode (not shown) in front of the display area. In this case, 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).

Subsequently, after the counter substrate (not shown) is positioned corresponding to the organic light emitting device substrate 101 according to the first embodiment of the present invention having the above-described configuration, the organic field in a vacuum atmosphere or an inert gas atmosphere. A seal pattern (not shown) may be formed and bonded along the edge of the light emitting device substrate 101 and the counter substrate (not shown), or between the organic light emitting device substrate 101 and the counter substrate (not shown). The organic electroluminescent device is completed by bonding through a face seal.

8A to 8C are cross-sectional views illustrating manufacturing steps of a substrate for an organic light emitting diode according to a second exemplary embodiment of the present invention. The manufacturing method of the organic light emitting device substrate according to the second embodiment of the present invention differs only in the manufacturing method of the organic light emitting device substrate according to the first embodiment and the shape of the exposure mask for forming the second protective layer. Only the other methods of forming the components are the same, so the differences will be described.

First, referring to FIG. 8A, an organic insulating layer 239 having a flat surface is formed by coating an organic insulating material having a positive photosensitive characteristic on the entire surface of the first protective layer 138 or the thin film transistor DTr. do.

In addition, the driving thin film transistor may include a blocking area BA having a blocking layer BL made of a material blocking light transmission in response to an edge of each pixel area P on the organic insulating layer 239. The drain electrode 136 of the DTr has a transmissive area TA and the other areas have the same slit spacing, or a multilayer film L1 made of the same number of organic or inorganic materials is provided. An exposure mask MSK having a transflective area HTA whose transmission amount is smaller than the transmission area TA is positioned. At this time, the transflective area (HTA) is characterized in that the transmission amount does not change by position.

Thereafter, after exposing the organic insulating layer 239 through the exposure mask MSK, and developing the same, a dam having a first height with respect to an edge of each pixel region P is illustrated in FIG. 7B. A drain having a shape 240b and a flat portion 240a having a flat surface inside the dam 240b of each pixel region P, and exposing the drain electrode 136 of the driving thin film transistor DTr. The second protective layer 240 having the contact hole 143 is formed.

Subsequently, as illustrated in FIG. 7C, a double layer structure of a highly reflective material / transparent conductive material is formed on the second protective layer 240 or a triple layer of a transparent conductive material / excellent reflective material / transparent conductive material. A first electrode 247 having a structure is formed. In this case, the first electrode 247 is formed so that the end thereof is located above the dam portion 240b of the second protective layer 240, so that the first electrode 247 has a cross section with respect to each pixel region P. FIG. It is characterized by the shape of the container having a sidewall portion 246 and a flat bottom portion 248.

Subsequently, the organic light emitting device substrate 201 according to the second embodiment of the present invention may be completed by performing the same process as the first embodiment.

9A to 9C are cross-sectional views illustrating manufacturing steps of a substrate for an organic light emitting diode according to a third exemplary embodiment of the present invention. The manufacturing method of the organic light emitting device substrate according to the third embodiment of the present invention differs only in the manufacturing method of the organic light emitting device substrate according to the first embodiment and the shape of the exposure mask for forming the second protective layer. Only the other methods of forming the components are the same, so the differences will be described.

First, referring to FIG. 9A, an organic insulating layer 339 having a flat surface is formed by coating an organic insulating material having a positive photosensitive characteristic on the entire surface of the first protective layer or the thin film transistor.

And a blocking area BA having an blocking layer BL made of a material blocking light transmission corresponding to an edge of each pixel area P on the organic insulating layer 339. The drain electrode 136 of the DTr has a transmissive area TA, and each of the pixel areas P has a plurality of slits SLT formed in a slit shape to form the pixel area P. The pixel has a semi-transmissive region that forms a structure in which the slit (SLT) gradually becomes denser from the center portion of the edge to the edge, or a multilayer of organic or inorganic materials that weaken the light transmittance and has different layers or thicknesses. An exposure mask MSK having a semi-transmissive area having a larger number or thicker structure is positioned from the center portion of the region P to the edge.

In this case, the transflective area HTA of the exposure mask MSK is made of an organic material that weakens the transmittance of light or a slit structure that becomes denser from the center to the edge of the pixel area P, or a multilayer of inorganic materials. All of the structures in which a greater number or thicker multilayers are formed from the center portion of the pixel region P toward the edge may be implemented.

In the figure, the exposure mask MSK in which the slit structure and the multilayer structure are mixed is shown as an example. In the exposure mask MSK having the above configuration, the transflective areas HTA1 and HTA2 are substantially divided into the first transflective area HTA1 and the second transflective area HTA2, and the first transflective area HTA1 is Both the slit SLT and the multilayer L2 are provided to have more light transmission from the inside of each pixel region P toward the center portion, and the second semi-transmissive region HTA2 is not provided with the slit SLT. It is characterized by forming a multi-layer (L2) structure to have a constant amount of light transmission.

Thereafter, the organic insulating layer 339 of FIG. 9A is exposed through the exposure mask MSK having such a shape, and then developed. Then, as shown in FIG. 9B, an edge of each pixel region P is formed. The dam portion 340b having a dam shape having a first height and a concave shape inside the dam portion 340b of each pixel region P may expose a drain electrode 136 of the driving thin film transistor DTr. The second protective layer 340 is formed of the concave recess 340a having the contact hole 143.

Thereafter, as illustrated in FIG. 9C, a double layer structure of a material having high reflectivity / transparent conductive material is formed on the second protective layer 340, or a triple layer of material having a high reflectivity / transparent conductive material / transparent conductive material. A first electrode 347 having a structure is formed. In this case, the first electrode 247 is formed so that the end thereof is located above the dam portion 340b provided in the second protective layer 340, so that the first electrode 347 is in each pixel region P. FIG. It is characterized in that the container has a concave bottom portion 346 and a side portion 348 bent from the bottom portion 346.

Subsequently, the same process as in the first embodiment can be performed to complete the substrate for an organic light emitting device according to the second embodiment of the present invention.

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

101: substrate for the organic light emitting 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: middle layer 147c: upper layer
150: bank 160: spacer
DA: driving area DTr: driving thin film transistor
P: Pixel Area StgA: Storage Area
StgC1, StgC2: first and second storage capacitors

Claims (20)

A substrate in which a display area having a plurality of pixel areas is defined;
A switching thin film transistor and a driving thin film transistor formed in each pixel area on the substrate;
A first passivation 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 thin film transistor for each pixel region;
The first protective layer has a concave structure toward the central portion for each pixel region, and the first electrode also has a concave structure toward the central portion within each pixel region under the influence of the first protective layer. Phosphorus organic light emitting element substrate.
A substrate in which a display area having a plurality of pixel areas is defined;
A switching thin film transistor and a driving thin film transistor formed in each pixel area on the substrate;
A first passivation 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 thin film transistor for each pixel region;
The first protective layer includes a dam portion having a shape surrounding the pixel region at an edge of each pixel region and a surface portion inside the dam portion, and the first electrode has an end portion thereof in each pixel region. A substrate for an organic light emitting device, characterized in that the end is bent to form a side wall by being located on the upper surface.
The method of claim 2,
The first protective layer has a flat surface portion or concave toward the center portion of each pixel region.
And the first electrode also has a flat bottom surface overlapping the surface portion of the first protective layer, or a concave shape toward the center of each pixel region.
4. The method according to any one of claims 1 to 3,
A bank overlapping an edge of the first electrode and formed at a boundary of the pixel region;
A spacer formed on the bank;
An organic emission layer formed on the first electrode in the bank;
A second electrode formed over the display area above the organic emission layer and the bank;
A substrate for an organic light emitting device, characterized in that it comprises a.
The method of claim 4, wherein
The first electrode is a substrate for an organic light emitting device, characterized in that a double layer or triple layer structure.
The method of claim 5, wherein
When the first electrode has a triple layer structure, the lower layer is made of a transparent conductive material, the middle layer is made of a metal material having excellent reflectance, and the upper layer is made of a transparent conductive material having a low work function value.
When the first electrode has a double layer structure, the first layer is made of a metal material having excellent reflectance, and the second layer is made of a transparent conductive material having a low work function value.
The method according to claim 6,
The transparent conductive material is indium tin oxide (ITO) or indium zinc oxide (IZO),
The metal material having excellent reflectance is any one of aluminum (Al), aluminum alloy (AlNd), silver (Ag), and APC (Ag, Pd, Cu alloy).
The method of claim 4, wherein
The first protective layer is made of an organic insulating material, the lower portion of the first protective layer is an organic light emitting device substrate, characterized in that further provided with a second protective layer made of an inorganic insulating material.
The method of claim 4, wherein
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 >
An organic light emitting device, characterized in that a counter substrate for encapsulation is provided facing the substrate.
Forming a switching thin film transistor and a driving thin film transistor in each pixel area on a substrate on which a display area having a plurality of pixel areas 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, the first protective layer having a concave structure toward the center of each pixel region;
Forming a first electrode on the first passivation layer in contact with the drain electrode of the driving thin film transistor for each pixel region and forming a concave structure in the pixel region for each pixel region. Manufacturing method.
11. The method of claim 10,
Forming the first protective layer,
Forming an organic insulating layer having a flat surface by applying a photosensitive organic insulating material onto the switching and driving thin film transistor;
Placing an exposure mask including a light transmitting region, a blocking region, and a semi-transmissive region over the organic insulating layer, and then exposing the organic insulating layer through the exposure mask;
Developing the exposed organic insulating layer
The exposure mask may include a structure in which the transflective area corresponding to each pixel area is formed in a slit shape, and the slit is gradually densified toward the edge from the center of each pixel area.
Alternatively, a multilayer film made of an organic material or an inorganic material, which weakens the light transmittance, may have a structure in which a plurality of layers or a plurality of thicknesses vary in thickness or thickness from the center to the edge of each pixel area, and at the boundary of each pixel area. Correspondingly, the blocking region is located, and the transmission region is located corresponding to the drain electrode.
Forming a switching thin film transistor and a driving thin film transistor in each pixel area on a substrate on which a display area having a plurality of pixel areas is defined;
A drain portion covering the switching and driving thin film transistors and exposing the drain electrodes of the driving thin film transistors, the dam portion having a shape surrounding the pixel regions at an edge of each pixel region, and a first protective layer having a surface portion inside the dam portion; Making a step;
Contacting the drain electrode of the driving thin film transistor for each pixel region on the first passivation layer and positioned at an upper side of the dam portion at each end of the pixel region to form a first electrode including a bottom portion and a bent sidewall portion; step
Method for producing a substrate for an organic light emitting device comprising a.
13. The method of claim 12,
Forming the first protective layer,
Forming an organic insulating layer having a flat surface by applying a photosensitive organic insulating material onto the switching and driving thin film transistor;
Placing an exposure mask including a light transmitting region, a blocking region, and a semi-transmissive region over the organic insulating layer, and then exposing the organic insulating layer through the exposure mask;
Developing the exposed organic insulating layer
Wherein the exposure mask has a structure in which the transflective area corresponding to each pixel area is formed of a multilayered film made of an organic material or an inorganic material that weakens the light transmittance, and a blocking area corresponding to the dam portion is positioned. And the transmission region is located in correspondence with the drain electrode.
13. The method of claim 12,
And the surface portion of the first passivation layer is flat in each pixel region or concave toward the center of each pixel region.
15. The method of claim 14,
Forming the first protective layer forming the concave shape of the surface portion,
Forming an organic insulating layer having a flat surface by applying a photosensitive organic insulating material onto the switching and driving thin film transistor;
Placing an exposure mask including a light transmitting region, a blocking region, and a semi-transmissive region over the organic insulating layer, and then exposing the organic insulating layer through the exposure mask;
Developing the exposed organic insulating layer
The exposure mask includes a blocking region having a blocking layer made of a material blocking light transmission, and a transmission region corresponding to the drain electrode of the driving thin film transistor.
A plurality of slits may be provided to correspond to each pixel area to form a slit shape, and the semi-transmissive area may form a structure in which the slits gradually become denser from the center to the edge of each pixel area.
Or a multi-layered organic or inorganic material that weakens the light transmittance and has a semi-transmissive region having a structure in which the number of layers or thicknesses is increased, the number of which is thicker or thicker from the center to the edge of each pixel region.
Alternatively, a semi-transmissive region in which a slit structure densifying toward the edge from the center of each pixel region and a multiplicity of weakening the transmittance of light are overlapped with a structure in which more or more thick layers are formed toward the edge from the center of each pixel region. The manufacturing method of the board | substrate for organic electroluminescent elements characterized by having.
The method according to any one of claims 10, 12 and 14,
Forming a bank overlapping an edge of the first electrode and bordering the pixel region;
Forming a spacer on the bank;
Forming an organic emission layer on the first electrode in the bank;
Forming a second electrode over the display area over the organic emission layer and the bank;
Method for producing a substrate for an organic light emitting device comprising a.
17. The method of claim 16,
The first electrode is a method of manufacturing a substrate for an organic light emitting device, characterized in that to form a double layer or triple layer structure.
The method of claim 17,
When the first electrode has a triple layer structure, a reflective layer and a second transparent conductive material layer formed of a first transparent conductive material layer and a metal material having excellent reflectivity and a second transparent conductive material layer are sequentially formed on the first protective layer. Patterning the transparent conductive material layer, the reflective layer, and the first transparent conductive material layer to form a first electrode constituting the triple layer structure,
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 electrode and the transparent conductive material layer are patterned to form a first electrode having the double layer structure. The manufacturing method of the board | substrate for organic electroluminescent elements characterized by the above-mentioned.
17. The method of claim 16,
And forming a second protective layer of an inorganic insulating material on the switching and driving thin film transistor before forming the first protective layer.
17. The method of claim 16,
The forming of the switching and driving thin film transistor may include forming a gate line and a data line crossing each other to define the pixel region, and a power line disposed to be parallel to the data line. 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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