KR102575459B1 - Organic light emitting display device and method for fabricating thereof - Google Patents

Abstract

The present invention discloses an organic light emitting display device and a manufacturing method thereof. An organic light emitting display device of the present invention disclosed herein is an organic light emitting display device in which a plurality of pixel areas including an emission area EA and a non-emission area NEA are defined, and a first layer disposed in the emission area EA is provided. A first electrode, an auxiliary electrode disposed in the non-emission area EA, first and second bank layers disposed with the auxiliary electrode interposed therebetween, the first electrode, the first and second bank layers, and a part of the auxiliary electrode An organic light emitting layer and a second electrode disposed on the organic light emitting layer, and an undercut region in which a part of the auxiliary electrode is exposed is provided between the second bank layer and the auxiliary electrode, thereby improving a pixel aperture ratio. can

Description

Organic light emitting display device and manufacturing method thereof

The present invention relates to an organic light emitting display device and a manufacturing method thereof.

BACKGROUND OF THE INVENTION As we enter the information age in earnest, a display field that visually displays electrical information signals is rapidly developing. Accordingly, research is being conducted to develop performance such as thinning, light weight, and low power consumption for various flat display devices.

Representative examples of such a flat panel display are a liquid crystal display device (LCD), a plasma display panel device (PDP), a field emission display device (FED), and an electroluminescent display device. (Electro Luminescence Display device: ELD), Electro-Wetting Display device (EWD), and Organic Light Emitting Display device (OLED).

Such flat panel display devices commonly include a flat panel display panel for realizing an image. Here, the flat panel display panel has a structure in which a pair of substrates are bonded face-to-face with a unique light emitting material or a polarizing material interposed therebetween, and includes a display surface defining a display area and a non-display area, which is an outside of the display area. Also, the display area is defined as a plurality of pixel areas.

Among them, an organic light emitting display device (OLED) is a device that displays an image using organic light emitting diodes, which are self-light emitting devices, and a plurality of organic light emitting diodes are disposed in a plurality of pixel areas.

The organic light emitting diode includes first and second electrodes facing each other, and an organic light emitting layer disposed between the first and second electrodes, and any one of the first and second electrodes (hereinafter referred to as “first electrode”) Assume that ) is formed to correspond to each pixel area, and the other electrode (hereinafter referred to as “second electrode”) is formed to commonly correspond to a plurality of pixel areas.

Unlike the first electrode formed to correspond to each pixel region, the second electrode has a higher resistance than the first electrode because it is formed to correspond to the entire pixel region. In particular, when the organic light emitting display device emits light along a path passing through the second electrode, the second electrode is formed of a transparent conductive material as thin as possible in order to increase light emission efficiency, that is, luminance, of each pixel area. can be, and thus have a higher resistance.

As described above, when the resistance of the second electrode is high, a larger voltage drop (IR drop) occurs, causing a problem in that the luminance of each pixel area varies depending on the distance from the power source. In addition, despite the voltage drop due to the high resistance of the second electrode, an applied voltage must be increased to secure luminance above a threshold, which increases power consumption of the organic light emitting display device.

In order to solve the above problems, in a conventional organic light emitting display device, a bank layer region dividing white (W), red (R), green (G), and blue (B) pixel regions has a lower resistance than the second electrode. An auxiliary electrode was formed, and a barrier rib structure connecting the second electrode to the auxiliary electrode was formed.

In the organic light emitting display device having the barrier rib structure as described above, it is difficult to apply the technology of using a shadow mask to prevent the organic light emitting layer from being formed on the auxiliary electrode formed between the pixel areas to the large area organic light emitting display device. the proposed method.

However, in the structure in which the barrier rib structure is formed between the pixel regions of the organic light emitting display device and the second electrode and the auxiliary electrode are electrically connected, a barrier rib must be additionally formed between the pixel regions in addition to the bank layer. There is a disadvantage in that it is difficult to apply to a high-resolution organic light emitting display device.

In addition, as described above, the method of additionally forming barrier ribs between pixel areas in addition to the bank layer has a problem in that there is a limitation in securing an aperture ratio of each pixel area.

According to the present invention, a bank layer having an undercut structure is formed between white (W), red (R), green (G), and blue (B) pixel regions to form a second electrode and an auxiliary electrode of an organic light emitting diode. An object of the present invention is to provide an organic light emitting display device having improved pixel aperture ratio by connecting the same and a method for manufacturing the same.

In addition, the present invention connects the second electrode and the auxiliary electrode of the organic light emitting diode only with a bank layer between white (W), red (R), green (G), and blue (B) pixel areas, so that pixels can be obtained even at high resolution. Another object is to provide an organic light emitting display device capable of securing an aperture ratio and a manufacturing method thereof.

In addition, in the present invention, when forming the first electrode of the organic light emitting diode, a sacrificial layer is formed on the auxiliary electrode to form a bank layer having an undercut structure overlapping the auxiliary electrode, thereby forming the second electrode of the organic light emitting diode as a bank Another object of the present invention is to provide an organic light emitting display device having improved pixel aperture ratio by directly contacting an auxiliary electrode under a layer and a method for manufacturing the same.

An organic light emitting display device of the present invention to solve the above problems of the prior art is an organic light emitting display device in which a plurality of pixel areas including an emission area EA and a non-emission area NEA are defined, a first electrode disposed in the emission area EA, an auxiliary electrode disposed in the non-emission area EA, first and second bank layers disposed with the auxiliary electrode interposed therebetween, the first electrode, and a first and an organic light emitting layer disposed on a portion of the second bank layer and the auxiliary electrode, and a second electrode disposed on the organic light emitting layer, wherein a portion of the auxiliary electrode is exposed between the second bank layer and the auxiliary electrode. furnish the area

In addition, a sacrificial layer pattern disposed in the undercut region of the second bank layer, the sacrificial layer pattern being any one selected from copper (Cu), molybdenum (Mo), and ITO/Cu, and the undercut of the second bank layer In the region, a second electrode extension portion extending from the second electrode is connected to the sacrificial layer pattern and the auxiliary electrode, and the second electrode is electrically separated from the undercut region of the second bank layer on the auxiliary electrode. The width (D) of the auxiliary electrode exposed area between the first and second bank layers is 3 to 5 μm, the organic light emitting layer is a white organic light emitting layer, and the organic light emitting display device has red (red) corresponding to the pixel areas. By further including R), green (G), blue (B), and white (W) color filter layers, there is an effect of improving a pixel aperture ratio.

In addition, the organic light emitting display device manufacturing method of the present invention includes providing a substrate having a plurality of pixel areas including an emission area (EA) and a non-emission area (NEA) defined, a thin film transistor and the above substrate on the substrate. Forming a planarization film on the thin film transistor, forming a first electrode in the light emitting area (EA) and an auxiliary electrode in the non-emission area (NEA) on the planarization film, forming a sacrificial layer on the auxiliary electrode, A first bank layer overlapping a portion of the first electrode and a portion of the auxiliary electrode to divide the pixel area, and a second bank layer facing the first bank layer and overlapping a portion of the first electrode and a portion of the sacrificial layer. forming an undercut region in the second bank layer by removing a portion of the sacrificial layer, and forming an organic light emitting layer and a second electrode on the substrate on which the first electrode, the first bank layer, and the second bank layer are formed. By including the step of forming a high resolution by connecting the second electrode and the auxiliary electrode of the organic light emitting diode only with the bank layer between the white (W), red (R), green (G) and blue (B) pixel areas. There is an effect of securing a pixel aperture ratio even in .

An organic light emitting display device and a method of manufacturing the same according to the present invention form a bank layer having an undercut structure between white (W), red (R), green (G), and blue (B) pixel areas, By connecting the second electrode of the diode and the auxiliary electrode, there is an effect of improving the pixel aperture ratio.

In addition, an organic light emitting display device and a method of manufacturing the same according to the present invention include a bank layer between white (W), red (R), green (G), and blue (B) pixel areas, and the second electrode and the organic light emitting diode. By connecting the auxiliary electrode, there is an effect of securing a pixel aperture ratio even at a high resolution.

In addition, the organic light emitting display device and method of manufacturing the same according to the present invention form a bank layer having an undercut structure overlapping with the auxiliary electrode by forming a sacrificial layer on the auxiliary electrode when forming the first electrode of the organic light emitting diode, The second electrode of the organic light emitting diode directly contacts the auxiliary electrode under the bank layer, thereby improving the pixel aperture ratio.

1 is a cross-sectional view illustrating a pixel area of an organic light emitting display device according to an embodiment of the present invention.
2 is a diagram illustrating a bank layer structure between pixel areas of an organic light emitting display device according to an embodiment of the present invention.
3A to 3G are diagrams illustrating a manufacturing process of an organic light emitting display device according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a state in which an upper metal layer and a lower metal layer are connected in a bank layer having an undercut structure used in an organic light emitting display device according to an exemplary embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, so the present invention is not limited to the details shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

When 'includes', 'has', 'consists of', etc. mentioned in this specification is used, other parts may be added unless 'only' is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

In interpreting the components, even if there is no separate explicit description, it is interpreted as including the error range.

In the case of a description of a positional relationship, for example, 'on top of', 'on top of', 'at the bottom of', 'next to', etc. Or, unless 'directly' is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, for example, when a temporal precedence relationship is described as 'after', 'continue to', 'after ~', 'before', etc., 'immediately' or 'directly' As long as ' is not used, non-continuous cases may also be included.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Each feature of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in a related relationship. may be

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. And in the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numbers indicate like elements throughout the specification.

1 is a cross-sectional view showing a pixel area of an organic light emitting display device according to the present invention, and FIG. 2 is a view showing a bank layer structure between pixel areas of the organic light emitting display device according to the present invention.

Referring to FIGS. 1 and 2 , the organic light emitting display device 100 of the present invention includes a plurality of pixel areas PA, and each pixel area PA is a light emitting area (emitting light for display). EA) and the non-emission area NEA other than that.

In the organic light emitting display device 100, a first substrate 101 on which a driving transistor DTr and an organic light emitting diode 114 are formed is encapsulated by a second substrate 170 with an encapsulation layer 160 interposed therebetween. (Encapsulation).

The encapsulation layer 160 may have a structure in which a plurality of inorganic layers and organic layers are alternately overlapped with each other.

The organic light emitting display device of the present invention may be a top emission type or a bottom emission type, and the organic light emitting layer 112 disposed on the organic light emitting diode 114 includes red (R), green (G), and blue ( It may be red (R), green (G), blue (B) and white (W) light emitting layers that generate B) and white (W) light or a single white (W) light emitting layer.

When the organic light emitting layer 112 is a white (W) light emitting layer, the second substrate 170 may further include red (R), green (G), blue (B), and white (W) color filter layers. . Hereinafter, the upper light emitting method will be mainly described, and a white (W) organic light emitting layer will be used for the organic light emitting layer 112, but the color filter layers of the second substrate 170 will be omitted.

Looking more closely, a light blocking layer 150 is disposed in the pixel area PA on the first substrate 101, and a driving transistor DTr is disposed on the light blocking layer 150 with the buffer layer 102 interposed therebetween. is placed The driving transistor DTr includes a semiconductor layer 104, a gate insulating layer 103, a gate electrode 105, an interlayer insulating layer 124, and source and drain electrodes 107a and 107b.

The semiconductor layer 104 is made of silicon, and its central portion is composed of an active region 104a constituting a channel, and source and drain regions 104b and 104c doped with high-concentration impurities on both sides of the active region 104a.

The semiconductor layer 104 may be formed of an oxide semiconductor material containing zinc (Zn), for example, zinc oxide (ZnO), indium gallium zinc oxide (InGaZnO4), etc. may be used, but is not limited thereto. .

A gate insulating layer 103 is formed above the semiconductor layer 104 .

A gate electrode 105 and a gate wiring (not shown) extending in one direction are formed on the gate insulating film 103 to correspond to the active region 104a of the semiconductor layer 104.

In addition, an interlayer insulating film 124 is formed on the entire upper surface of the gate electrode 105 and the gate wiring (not shown).

The interlayer insulating layer 124 and the gate insulating layer 103 therebelow have contact holes exposing source and drain regions 104b and 104c located on both sides of the active region 104a, respectively.

Source and drain electrodes 107a and 107b spaced apart from each other and contacting the source and drain regions 104b and 104c exposed through the contact hole are disposed above the interlayer insulating layer 124 including the contact hole.

Accordingly, the driving transistor DTr is composed of the semiconductor layer 104, the gate insulating layer 103, the gate electrode 105, the interlayer insulating layer 124, and the source and drain electrodes 107a and 107b. . In addition, although not shown in the drawings, not only the driving transistor DTr but also a plurality of switching transistors are disposed in the pixel area of the organic light emitting display device 100. The structure of the switching transistor is the same as that of the driving transistor DTr. same.

In addition, a passivation layer 106 and a planarization layer 108 having a drain contact hole (CH) exposing the drain electrode 107b to an upper portion of the interlayer insulating layer 124 disposed on the source and drain electrodes 107a and 107b. ) is formed.

Meanwhile, although not shown, a data line (not shown) crossing a gate line (not shown) to define the pixel area PA is formed simultaneously with the source and drain electrodes 107a and 107b. In addition, power wiring (not shown) and the like are formed in a direction parallel to the data wiring (not shown).

The first electrode 111 of the organic light emitting diode 114 electrically connected to the drain electrode 107b through the drain contact hole CH is disposed in the light emitting region EA above the planarization layer 108. there is.

In addition, an auxiliary electrode 110 made of the same material as the first electrode 111 is disposed in the non-emission area NEA. The first electrode 111 and the auxiliary electrode 110 are formed of a material having a relatively high work function value and serve as an anode of the organic light emitting diode 114 .

Therefore, the first electrode 111 and the auxiliary electrode 110 may be formed of a metal, an alloy thereof, a combination of a metal and an oxide metal, for example, Ag, Al, AlNd, Au, Mo, W, Cr, It can be formed from one of these alloys, ITO, IZO, ITO/APC/ITO, AlNd/ITO, Ag/ITO or ITO/APC (Ag-Pd-Cu)/ITO.

In addition, first and second bank layers 115 and 116 are disposed in the non-emission area NEA to expose the first electrode 111 and the auxiliary electrode 110 to the outside while partitioning the emission area EA. .

In the organic light emitting display device 100 of the present invention, the first bank layer 115 is disposed in the drain contact hole CH that contacts the drain electrode 107b of the driving transistor DTr in the pixel area PA, A second bank layer 116 having an undercut structure is disposed in an adjacent pixel area with the first bank layer 115 and the auxiliary electrode 110 interposed therebetween.

The second bank layer 116 has an under cut region (UCR) in an area overlapping the auxiliary electrode 110, and a part of the auxiliary electrode 110 is electrically connected to the inside of the under cut region. The sacrificial layer pattern 120 in contact with is disposed.

In particular, in the prior art, an auxiliary electrode is exposed between bank layers, and a barrier rib is disposed on the exposed auxiliary electrode, so that the area where the auxiliary electrode is exposed is 20 μm or more, but in the present invention, the first and second bank layers The aperture ratio of the pixel region was increased by setting the width D of the exposed region of the auxiliary electrode 110 between the fields 115 and 116 to be 3 to 5 μm.

As shown in FIG. 2, since the width D of the exposed area between the first and second bank layers 115 and 116 is 3 to 5 μm in the direction of the upper and lower pixel areas P1 and P2, The gap between the pixel regions P1 and P2 may be narrowed while the aperture ratios of the pixel regions P1 and P2 are increased. Therefore, in the present invention, when the organic light emitting display device is a high-resolution model, the distance between the pixel areas P1 and P2 is close, but the aperture ratio of the pixel area may be rather increased.

An organic light emitting layer 112 and a second electrode 113 serving as a cathode are disposed on the light emitting region, the non-emitting region, the first bank layer 115 and the second bank layer 116, and the first And on the exposed auxiliary electrode 110 between the second bank layers 115 and 116, an organic emission layer extension 112a and a second electrode extension 113a are respectively stacked.

In particular, in the organic light emitting display device 100 of the present invention, the second electrode extension 113a extends to the undercut region of the second bank layer 116, and exposes the second electrode extension 113a. A portion of the auxiliary electrode 110 and the sacrificial layer pattern 120 are electrically connected to each other.

In addition, a second substrate 170 is bonded between the second electrode 113 and the second electrode extension 113a with an encapsulation layer 160 interposed therebetween.

Therefore, in the present invention, unlike the prior art, there is no need to dispose a barrier rib for electrically connecting the second electrode and the auxiliary electrode of the organic light emitting diode between the pixel areas, thereby increasing the aperture ratio of the pixel area.

In addition, in the present invention, the electrode of the organic light emitting diode is formed on the bank layer having an undercut structure, and the second electrodes are separated in pixel area units by the undercut structure, so that they can directly contact the exposed auxiliary electrode. , there is an effect of securing a pixel aperture ratio even at a high resolution.

3A to 3G are diagrams illustrating a manufacturing process of an organic light emitting display device according to an embodiment of the present invention.

Referring to FIGS. 3A to 3G together with FIG. 1 , the organic light emitting display device of the present invention includes a plurality of pixel areas PA, each pixel area PA including an emission area EA emitting light for display and , and is partitioned into the non-emission area NEA other than that.

First, a first substrate 101 made of a transparent insulating material partitioned into the pixel area PA, light emitting area EA, and non-light emitting area NEA is provided.

After forming a metal film on the first substrate 101, a mask process is performed to form a light blocking layer 150 in an area where the driving transistor DTr is to be formed. The light blocking layer 150 may use a metal such as chromium (Cr) having excellent light absorption or a black resin.

The mask process refers to a series of processes of forming a photoresist film on a substrate, performing exposure and development using a mask to form a predetermined photoresist film pattern, and then performing an etching process using the photoresist film pattern as an etching mask.

As described above, when the light blocking layer 150 is formed on the first substrate 101, the buffer layer 102 made of an insulating material is formed on the entire surface of the first substrate 101, and then the first substrate ( 101) to form a semiconductor layer 104.

The semiconductor layer 104 includes an active region 104a forming a channel in the center, and source and drain regions 104b and 104c doped with high-concentration impurities on both sides of the active region 104a.

The semiconductor layer 104 may be an amorphous silicon layer and doped amorphous silicon layer or a crystallized silicon layer. Also, the semiconductor layer 104 may be an oxide semiconductor.

When the semiconductor layer 104 is an oxide semiconductor, it may be made of an amorphous oxide containing at least one of indium (In), zinc (Zn), gallium (Ga), or hafnium (Hf). For example, when a Ga-In-Zn-O oxide semiconductor is formed by a sputtering process, each target formed of In2O3, Ga2O3, and ZnO may be used, or a single target of Ga-In-Zn oxide may be used. In addition, when the hf-In-Zn-O oxide semiconductor is formed by a sputtering process, each target formed of HfO2, In2O3, and ZnO may be used, or a single target of Hf-In-Zn oxide may be used.

As described above, when the semiconductor layer 104 is formed on the first substrate 101, as shown in FIG. 3B, the gate insulating film 103 and the gate metal film are continuously formed on the entire surface of the first substrate 101. After forming, a mask process is performed to form a gate electrode 105 on the active region 104a of the semiconductor layer 104 . A gate insulating layer 103 is formed between the gate electrode 105 and the active region 104a.

The gate metal layer may include aluminum (Al), aluminum alloy (Al alloy), tungsten (W), copper (Cu), nickel (Ni), chromium (Cr), molybdenum (molybdenum); Mo), titanium (Ti), platinum (Pt), tantalum (tantalum (Ta), etc., a metal film of any one of low resistance opaque conductive materials, or a double film structure including an alloy of these materials, or at least two The above metal films may be formed in a stacked structure.

In addition, the gate insulating film 103 may be formed of a single layer of silicon oxide (SiOx) or a double layer in which silicon nitride (SiNx) and silicon oxide (SiOx) are sequentially deposited.

As described above, when the gate electrode 105 is formed on the first substrate 101, as shown in FIG. 3C, an interlayer insulating film 124 is formed on the entire surface of the first substrate 101, and a mask process is performed. to form contact holes in regions corresponding to the source and drain regions 104b and 104c.

Then, a source/drain metal film is formed on the entire surface of the first substrate 101, and a mask process is performed to form the source electrode 107a and the drain electrode 107b.

The source/drain metal film may use a low-resistance opaque conductive material such as aluminum, aluminum alloy, tungsten, copper, nickel, chromium, molybdenum, titanium, platinum, or tantalum. In addition, a multilayer structure in which a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) and an opaque conductive material may be stacked may be formed.

As described above, when the source and drain electrodes 107a and 107b are formed on the first substrate 101, the passivation layer 106 and the planarization layer 108 are continuously formed on the entire surface of the first substrate 101. After the formation, a mask process is performed to form a drain contact hole (CH) exposing a part of the drain electrode 107b.

The passivation layer 106 may be formed of an inorganic insulating material such as silicon oxide (SiO2) or silicon nitride (SiNx), and the planarization layer 108 is an acryl-based organic compound, BCB (benzo-cyclo-butene) ) or organic insulating materials such as PFCB (perfluorocyclobutane) can be used.

As described above, when the drain contact hole (CH) is formed in the planarization layer 108, a first metal layer is formed on the entire surface of the first substrate 101, and then the organic light emitting diode 114 is formed according to a mask process. A first electrode 111 and an auxiliary electrode 110 are formed.

The first electrode 111 is electrically connected to the drain electrode 107b disposed below through the drain contact hole CH.

The first metal film constituting the first electrode 111 is formed of aluminum (Al), silver (Ag) or an alloy thereof, ITO (Indium Tin Oxide)/Ag, ITO (Indium Tin Oxide)/Ag/ITO, ITO (Indium Tin Oxide)/Ag/IZO (Indium Zinc Oxide), ITO/APC/ITO, and the like.

As described above, when the first electrode 111 and the auxiliary electrode 110 are formed, a second metal film is formed on the first substrate 101 and then sacrificed on the auxiliary electrode 110 according to a mask process. Layer 120a is formed.

The second metal film may be formed of one material selected from copper (Cu), molybdenum (Mo), and ITO/Cu. More specifically, it is preferable that the etching selectivity of the first metal layer and the second metal layer are different from each other.

However, if a halftone mask or diffraction mask process is used, first and second metal films are sequentially formed on the first substrate 101, and then the organic light emitting diode 114 is formed in the pixel area PA according to the mask process. ) of the first electrode 111 and the auxiliary electrode 110 are formed.

Thereafter, an etching process is performed to leave the sacrificial layer 120a only on the auxiliary electrode 110 . That is, in the present invention, when the first electrode 111 is formed, the auxiliary electrode 110 on the planarization film 108 and the sacrificial layer 120a may be formed on the auxiliary electrode 110 at the same time.

The first electrode 111 and the auxiliary electrode 110 are formed of the same first metal film, and the sacrificial layer 120a is made of second metal film materials such as copper (Cu), molybdenum (Mo), and ITO/Cu. It can be formed with any selected one.

As described above, when the first electrode 111 and the auxiliary electrode 110 are formed on the first substrate 101, an organic insulating layer is formed on the entire surface of the first substrate 101, and then the mask process is performed. A first bank layer 115 is formed on a portion of the auxiliary electrode 110 adjacent to a portion of the first electrode 111 in the drain contact hole (CH) region. In addition, the second bank layer ( 116) form.

Therefore, the auxiliary electrode 110 and a portion of the sacrificial layer 120a are exposed between the first bank layer 115 and the second bank layer 116 .

As described above, when the first and second bank layers 115 and 116 are formed on the first substrate 101, an etching process is performed using the first and second bank layers 115 and 116 as masks. , An undercut region UCR is formed in a region where the second bank layer 116 and the sacrificial layer 120a overlap.

The undercut region UCR is formed when a portion of the sacrificial layer 120a to be exposed and a portion of the sacrificial layer 120a overlapped by the second bank layer 116 are removed by etching. Therefore, as shown in the drawing, a portion of the sacrificial layer 120a is not etched and a sacrificial layer pattern 120 is formed in the overlapping region of the edge of the second bank layer 116 and the auxiliary electrode 110. do.

As described above, when the undercut structure is formed in the second bank layer 116 on the first substrate 101, the organic light emitting layer 112 and the second electrode 113 are formed on the first substrate 101. Thus, the organic light emitting diode 114 is formed in each pixel area PA.

Since the organic light emitting layer 112 is formed on the entire surface of the first substrate 101, the first electrode 111 and the upper portion of the first and second bank layers 115 and 116 and the exposed auxiliary electrode 110 is formed The organic emission layer 112 formed on the exposed auxiliary electrode 110 is referred to as an organic emission layer extension 112a.

The organic emission layer extension 112a is formed on the auxiliary electrode 110 by being separated from the edge region of the second bank layer 116 on the auxiliary electrode 110 .

The organic light emitting layer 112 and the organic light emitting extension part 112a may be composed of a single layer made of a light emitting material, and to increase light emitting efficiency, a hole injection layer, a hole transport layer, and a light emitting layer It may be composed of multiple layers of an emitting material layer, an electron transport layer, and an electron injection layer.

In addition, the hole transport layer (HTL) may further include an electron blocking layer (EBL), and the electron transport layer (ETL) may be formed using a low molecular weight material such as PBD, TAZ, Alq3, BAlq, TPBI, or Bepp2 there is.

Since the light emitting layer EML of the organic light emitting layer 112 emits different colors depending on the organic material, red (R), green (G), and blue (B) light emitting layers are formed for each pixel area, so that full color (Full color) color), or the light emitting layer EML can be implemented as a white light emitting layer in which red (R), green (G), and blue (B) organic materials are stacked.

As described below, when red (R), green (G), blue (B), and white (W) color filter layers are formed on the second substrate 170 bonded to the first substrate 101, the organic light emitting layer (112) uses an organic light emitting layer that generates white light.

In addition, the second electrode 113 is formed to cover the organic light emitting layer extension 112a formed on the organic light emitting layer 112 and the auxiliary electrode 110. The second electrode 113 is separated from the edge area of the second bank layer 116 .

In the present invention, by forming an undercut structure in the second bank layer 116, the separated second electrode 113 is deposited into the undercut region UCR of the second bank layer 116, and the lower auxiliary It is electrically connected to the electrode 110 and the sacrificial layer pattern 120 .

The second electrode 113 may be formed of indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) that can serve as an anode.

As shown in FIG. 3G , the second electrode extension 113a is disposed within the auxiliary electrode 110 disposed below the second bank layer 116 in the undercut region UCR and inside the undercut region UCR. It can be seen that it is electrically connected to the sacrificial layer pattern 120.

As described above, when the second electrode 113 of the organic light emitting diode 114 is formed on the first substrate 101, the first substrate 101 and the second substrate 160 are interposed therebetween. 170 is bonded to complete the organic light emitting display device.

Therefore, in the present invention, unlike the prior art, the second electrode 113 formed in each pixel area PA is provided without forming a separate barrier rib to separate the second electrode 113 from the auxiliary electrode 110 area. It may be electrically connected to the auxiliary electrode 110 .

As such, the organic light emitting display device and method of manufacturing the same of the present invention form a bank layer having an undercut structure between white (W), red (R), green (G), and blue (B) pixel regions, , there is an effect of improving the pixel aperture ratio by connecting the second electrode and the auxiliary electrode of the organic light emitting diode.

In addition, an organic light emitting display device and a method of manufacturing the same according to the present invention include a bank layer between white (W), red (R), green (G), and blue (B) pixel areas, and the second electrode and the organic light emitting diode. By connecting the auxiliary electrode, there is an effect of securing a pixel aperture ratio even at a high resolution.

In addition, the organic light emitting display device and method of manufacturing the same according to the present invention form a bank layer having an undercut structure overlapping with the auxiliary electrode by forming a sacrificial layer on the auxiliary electrode when forming the first electrode of the organic light emitting diode, The second electrode of the organic light emitting diode directly contacts the auxiliary electrode under the bank layer, thereby improving the pixel aperture ratio.

FIG. 4 is a diagram illustrating a state in which an upper metal layer and a lower metal layer are connected in a bank layer having an undercut structure used in an organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 4 together with FIG. 1 , as shown in FIG. 1 of the present invention, the bank layer BL having an undercut region UCR on the first metal layer ML1 corresponding to the auxiliary electrode 110 ) was formed. A sacrificial layer pattern SL is disposed at an inner edge of the undercut region UCR of the bank layer BL, and an undercut region UCR extends from the sacrificial layer pattern SL to the edge of the bank layer BL. A space is created.

When the second metal layer ML2 is formed on the bank layer BL and the first metal layer ML1 having the above structure, the first metal layer ML1 on which the bank layer BL is not formed has the above A second metal layer ML2 is stacked, and the second metal layer ML2 formed on the bank layer BL is stacked on the first metal layer ML1 in an edge region of the bank layer BL. It is separated from ML2).

At this time, a portion of the second metal layer ML2 is formed to the inner side of the undercut region of the bank layer BL by a deposition process, so that the edge extension of the second metal layer ML2 forms the sacrificial layer pattern SL. It is formed by extending to the area where it is located.

As described above, when the second metal layer ML2 is extended to the undercut region of the bank layer BL, the second metal layer ML2, the sacrificial layer pattern SL, and the first metal layer formed in the undercut region form electrically connected to each other.

That is, as shown in FIG. 1 , when a metal film made of a transparent conductive material (ITO, IZO, or ITZO) is deposited, the metal film penetrates into the undercut region formed by the bank layer BL, and the metal film is deposited even in the undercut region.

Due to this, the second electrode 113 of the organic light emitting diode 114 is deposited inside the undercut region UCR of the second bank layer 116, and the second electrode extension 113a, the undercut The auxiliary electrode 110 and the sacrificial layer pattern 120 of the region are electrically connected to each other.

Therefore, as in the present invention, by forming a bank layer having an undercut region, separation and separation of the second electrode and Electrical contact with the lower auxiliary electrode may be implemented.

Accordingly, an organic light emitting display device and a manufacturing method thereof according to the present invention form a bank layer having an undercut structure between white (W), red (R), green (G), and blue (B) pixel regions, By connecting the second electrode and the auxiliary electrode of the organic light emitting diode, there is an effect of improving a pixel aperture ratio.

In addition, an organic light emitting display device and a method of manufacturing the same according to the present invention include a bank layer between white (W), red (R), green (G), and blue (B) pixel areas, and the second electrode and the organic light emitting diode. By connecting the auxiliary electrode, there is an effect of securing a pixel aperture ratio even at a high resolution.

In addition, the organic light emitting display device and method of manufacturing the same according to the present invention form a bank layer having an undercut structure by forming a sacrificial layer on the first electrode of the organic light emitting diode, thereby forming a bank layer for the second electrode of the organic light emitting diode. There is an effect of improving the aperture ratio by directly contacting the auxiliary electrode under the layer.

100: organic light emitting display device
101: first substrate
102: buffer layer
103: gate insulating film
104: semiconductor layer
105: gate electrode
106: shield
108: planarization film
114: organic light emitting diode
DTr: driving transistor

Claims (14)

In the organic light emitting display device in which a plurality of pixel areas including an emission area (EA) and a non-emission area (NEA) are defined,
a first electrode disposed in the light emitting area EA;
an auxiliary electrode disposed in the non-emission area NEA;
first and second bank layers disposed with the auxiliary electrode interposed therebetween;
an organic light emitting layer disposed on a part of the first electrode, the first and second bank layers, and the auxiliary electrode; and
A second electrode disposed on the organic light emitting layer;
an undercut region in which a portion of the auxiliary electrode is exposed between the second bank layer and the auxiliary electrode;
a sacrificial layer pattern disposed in an undercut region of the second bank layer;
A second electrode extension extending from the second electrode is connected to the sacrificial layer pattern and the auxiliary electrode in an undercut region of the second bank layer;
The second bank layer is directly positioned on the sacrificial layer pattern,
The sacrificial layer pattern is an organic light emitting display device formed of a single material layer.
delete The organic light emitting display device of claim 1 , wherein the sacrificial layer pattern is made of one selected from copper (Cu) and molybdenum (Mo).
delete The organic light emitting display device of claim 1 , wherein the second electrode is electrically separated from an undercut region of the second bank layer on the auxiliary electrode.
The organic light emitting display device of claim 1 , wherein a width (D) of the auxiliary electrode exposed area between the first and second bank layers is 3 μm to 5 μm.
The organic light emitting display device of claim 1 , wherein the organic light emitting layer is a white organic light emitting layer.
The organic light emitting display device of claim 7 , further comprising red (R), green (G), blue (B), and white (W) color filter layers respectively corresponding to the pixel areas.
providing a substrate in which a plurality of pixel areas including an emission area (EA) and a non-emission area (NEA) are defined;
forming a thin film transistor on the substrate and a planarization film on the thin film transistor;
forming a first electrode in the emission area (EA) and an auxiliary electrode in the non-emission area (NEA) on the planarization film;
forming a sacrificial layer on the auxiliary electrode;
A first bank layer overlapping a portion of the first electrode and a portion of the auxiliary electrode to divide the pixel area, and a second bank layer facing the first bank layer and overlapping a portion of the first electrode and a portion of the sacrificial layer. forming;
forming an undercut region in the second bank layer by removing a portion of the sacrificial layer; and
forming an organic light emitting layer and a second electrode on the substrate on which the first electrode, the first bank layer, and the second bank layer are formed;
A sacrificial layer pattern, which is a single material layer, is formed inside the undercut region,
In an undercut region of the second bank layer, a second electrode extension portion in which the second electrode extends contacts the sacrificial layer pattern and the auxiliary electrode;
The second bank layer is directly positioned on the sacrificial layer pattern.
delete 10. The method of claim 9, wherein the auxiliary electrode and the sacrificial layer have different etch selectivity from each other.
10. The method of claim 9, wherein the first electrode and the auxiliary electrode are aluminum (Al), silver (Ag) or an alloy thereof, ITO (Indium Tin Oxide) / Ag, ITO (Indium Tin Oxide) / Ag / ITO, ITO (Indium A method for manufacturing an organic light emitting display device selected from among Tin Oxide)/Ag/IZO (Indium Zinc Oxide) and ITO/APC/ITO.
The method of claim 9 , wherein the sacrificial layer is made of one selected from copper (Cu) and molybdenum (Mo).
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