KR20060000355A - Organic electro-luminescence display device and fabricating method of the same - Google Patents

Abstract

The present invention relates to an organic light emitting display device and a method of manufacturing the same. In the case of using aluminum alloy ACX as a reflecting film, a protective film is formed on the surface of the reflecting film by forming a reflecting film with the ACX and then forming a protective film on the surface of the reflecting film. It is a technique that can prevent ACX from being damaged by the developing solution of the subsequent pixel definition film and thereby prevent the deterioration of the optical properties.

Reflective film, protective film, cleaning.

Description

Organic electroluminescent display device and method of manufacturing the same {Organic electro-luminescence display device and fabricating method of the same}

1 is a cross-sectional view of an organic light emitting display device according to the prior art.

2 is a cross-sectional view of an organic light emitting display device in which a reflective film is damaged due to penetration of a developer.

3 is a photograph of an organic light emitting display device according to the prior art.

4 is a cross-sectional view of an organic light emitting display device according to the present invention;

5 is a cross-sectional view of an organic light emitting display device having a reflective film having a protective film according to the present invention.

6 is a photograph of an organic electroluminescent display device according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100, 200: transparent insulation substrate 110, 210: buffer film

120, 220 polysilicon layer patterns 122, 222: source / drain regions

130, 230: gate insulating film 132, 232: gate electrode

140, 240: interlayer insulating film 150, 250: source electrode

152, 252: drain electrodes 160, 260: protective film

170 and 270: planarization film 180 and 280: reflection film

182, 282: pixel electrode 281: protective film

190, 290: Pixel defining layer patterns 192, 292: Light emitting layer

194: defects

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device and a method of manufacturing the same, and more particularly, to form a protective film on the surface of the reflective film to prevent damage to the reflective film by a developer used during patterning of the pixel definition layer. And to a method for producing the same.

In general, an organic light emitting display device is a self-luminous display device that electrically excites fluorescent organic compounds to emit light. This is divided into a passive matrix method and an active matrix method according to a method of driving N × M pixels arranged in a matrix form. The active matrix type organic light emitting display device has less power consumption than the passive matrix type, is suitable for large area, and has a high resolution. In addition, the organic light emitting display device is classified into a top emission type or a bottom emission type according to the emission direction of light emitted from the organic compound. Unlike the bottom emission type, the top emission type organic light emitting display device emits light in a direction opposite to the substrate where the unit pixels are located, and has a large aperture ratio. As mentioned above, the organic light emitting display device is a self-luminous type and does not require a separate light source, but in order to increase the light emitting efficiency, a reflective film is formed of a metal having excellent light reflection characteristics to reflect light from the outside to the light source Also used.

1 is a cross-sectional view of a conventional organic light emitting display device.

First, a buffer film 110 having a predetermined thickness is formed on the front surface of the transparent insulating substrate 100 by a plasma-enhanced chemical vapor deposition (PECVD) method. In this case, the buffer layer 110 prevents the diffusion of impurities in the transparent insulating substrate 100 during the crystallization process of the amorphous silicon layer formed in a subsequent process.

Next, an amorphous silicon layer (not shown) having a predetermined thickness is deposited on the buffer layer 110. Subsequently, the amorphous silicon layer is crystallized by using Excimer Laser Annealing (ELA), Sequential Lateral Solidification (SLS), Metal Induced Crystallization (MIC), or Metal Induced Lateral Crystallization (MILC), and patterned polycrystalline silicon by photolithography. The layer pattern 120 is formed.

Next, a gate insulating film 130 is formed over the entire surface. In this case, the gate insulating layer 130 may be formed using a silicon oxide layer (SiO ₂ ), a silicon nitride layer (SiN _x ), or a stacked structure thereof.

Next, a single layer of an aluminum alloy such as aluminum (Al) or aluminum-neodymium (Al-Nd), or an aluminum alloy is laminated on a chromium (Cr) or molybdenum (Mo) alloy on the gate insulating layer 130. A metal layer for a gate electrode (not shown) is formed of multiple layers. Subsequently, the gate electrode metal layer is etched by a photolithography process to form a gate electrode 132. Subsequently, impurities are ion implanted into both polysilicon layer patterns 120 of the gate electrode 132 to form the source / drain regions 122.

Next, an interlayer insulating film 140 of a predetermined thickness is formed on the entire surface. Here, the interlayer insulating film 140 is formed using a silicon oxide film.

Next, the interlayer insulating layer 140 and the gate insulating layer 130 are etched by a photolithography process to form contact holes (not shown) for exposing the source / drain regions 122.

Next, an electrode material is formed on the entire surface including the contact hole, and the source / drain electrodes 150 and 152 connected to the source / drain regions 122 are formed by etching the electrode material by a photolithography process. do. In this case, as the electrode material, molybdenum tungsten (MoW) or aluminum-neodymium (Al-Nd) may be used.

Thereafter, the protective film 160 is formed over the entire surface by using an inorganic insulating film such as a silicon nitride film having a predetermined thickness.

Next, a first via contact hole (not shown) is formed to expose one of the source / drain electrodes 150 and 152 by a photolithography process.

Next, the planarization film 170 is formed on the entire surface.

Subsequently, a second via contact hole (not shown) is formed through the first via contact hole to expose one of the source / drain electrodes 150 and 152 through a photolithography process.

Next, a reflective film (not shown) is formed over the entire surface. In this case, the reflective film is formed using a metal layer having excellent reflection efficiency, and aluminum (Al), silver (Ag), palladium (Pd), or an alloy material thereof may be used.

Next, the reflective film is etched by the photolithography process to form the reflective film pattern 180 in the emission region.

Next, a metal layer for pixel electrodes is formed on the entire surface. In this case, a transparent metal layer such as ITO is used as the pixel electrode metal layer.

Next, the pixel electrode metal layer is etched by a photolithography process and is connected to any one of the source / drain electrodes 150 and 152, for example, the drain electrode 152, through the second via contact hole. 182 is formed.

Subsequently, a pixel definition layer (not shown) is formed over the entire surface. In this case, the pixel definition layer is an organic insulating layer, and a material selected from the group consisting of polyimide, benzocyclobutene series resin, phenol resin, and acrylate. It can be formed as. The thin film may be patterned by a photo process performed by exposure and development processes.

Next, the pixel definition layer is patterned by a photo process to form a pixel definition layer pattern 190 that exposes the emission region.

Next, an organic layer including at least a light emitting layer 192 is formed on the surface of the pixel electrode 182 exposed by the pixel defining layer pattern 190.

Thereafter, a counter electrode (not shown) is formed over the entire surface. The counter electrode is formed using a transparent metal layer.

As described above, the organic light emitting display device according to the related art is a top emission type organic light emitting display device and forms a reflective film in the light emitting area in order to increase the luminous efficiency. As the reflective film, various metal layers having excellent light reflectivity may be used, but aluminum alloy is used as the reflective film. Since the top emission type organic light emitting display device uses a resonance phenomenon of light, it is advantageous to form a thin thickness of the pixel electrode in the light emitting efficiency. However, when the thickness of the pixel electrode is made thin, as shown in FIG. 2, a developer used to pattern a subsequent pixel definition layer penetrates through a pinhole present in the pixel electrode to corrode a reflective film pattern to form a defect 194. There is a problem. As shown in FIG. 3, the reflective film pattern eroded by the developer appears as a defect in the light emitting region, thereby inhibiting optical characteristics, thereby lowering the process yield.

An object of the present invention is to solve the above problems of the prior art, the present invention is to form a protective film, and to wash the reflective film with deionized water to form a protective film on the surface of the reflective film to prevent corrosion of the reflective film by the developer Accordingly, an object of the present invention is to provide an organic electroluminescent display device and a method of manufacturing the same, which can improve optical characteristics.

In order to achieve the above object, the organic light emitting display device according to the present invention,

A thin film transistor including a gate electrode and a source / drain electrode on the transparent insulating substrate;

A reflective film pattern provided in an upper emission area of the insulating film including a via contact hole on the transparent insulating substrate and including a protective film on an upper side thereof;

A pixel electrode connected to any one of the source / drain electrodes through the via contact hole on the light emitting region of the transparent insulating substrate;

An organic film layer provided in a light emitting area above the pixel electrode and having at least a light emitting layer;

It includes a counter electrode provided on the organic film layer,

The reflective film is aluminum and nickel alloy,

The nickel content is less than 3%,

The thickness of the said reflective film is 500-3000 GPa,

The protective film is an oxide of the reflective film,

The protective film has a thickness of 10 to 100 kPa

The pixel electrode is characterized in that the thickness of 50 ~ 200Å.

In order to achieve the above object, the manufacturing method of the organic light emitting display device according to the present invention,

Forming an insulating film on the transparent insulating substrate having a thin film transistor including a gate electrode and a source / drain electrode;

Forming a via contact hole to expose any one of the source / drain electrodes by etching the insulating layer by a photolithography process;

Forming a reflective film on the entire surface;

Washing the reflective film to form a protective film on the reflective film surface;

Forming a reflective film pattern on the light emitting region of the insulating film of the transparent insulating substrate by etching the protective film and the reflective film by a photolithography process;

Forming a pixel electrode connected to any one of the source / drain electrodes through the via contact hole;

Forming a pixel definition film pattern exposing the light emitting area over the entire surface;

Forming an organic film including at least a light emitting layer in a light emitting region of the pixel electrode;

Forming a counter electrode over the entire surface,

The reflective film is formed of aluminum and nickel alloy,

The nickel content is less than 3%,

The reflecting film is formed to have a thickness of 500 to 3000 kPa,

The washing step is carried out using deionized water,

The washing step is carried out for 30 to 120 seconds,

The protective film is an oxide of the reflective film,

The protective film has a thickness of 10 to 100 kPa,

The pixel electrode may be formed to have a thickness of 50 to 200 mW.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

4 is a cross-sectional view of an organic light emitting display device according to the present invention.

First, a buffer film 210 having a predetermined thickness is formed on the front surface of the transparent insulating substrate 200 by a plasma-enhanced chemical vapor deposition (PECVD) method. In this case, the buffer layer 210 prevents the diffusion of impurities in the transparent insulating substrate 200 during the crystallization process of the amorphous silicon layer formed in a subsequent process.

Next, an amorphous silicon layer (not shown) having a predetermined thickness is deposited on the buffer film 210. Subsequently, the amorphous silicon layer is crystallized by using Excimer Laser Annealing (ELA), Sequential Lateral Solidification (SLS), Metal Induced Crystallization (MIC), or Metal Induced Lateral Crystallization (MILC), and patterned polycrystalline silicon by a photolithography process. The layer pattern 220 is formed.

Next, a gate insulating film 230 is formed over the entire surface. In this case, the gate insulating film 230 may be formed using a silicon oxide film (SiO ₂ ), a silicon nitride film (SiN _x ), or a stacked structure thereof.

Next, a single layer of an aluminum alloy such as aluminum (Al) or aluminum-neodymium (Al-Nd) on the gate insulating layer 230, or a multi-layered aluminum alloy on a chromium (Cr) or molybdenum (Mo) alloy As a layer, a metal layer (not shown) for the gate electrode is formed. Subsequently, the gate electrode metal layer is etched by the photolithography process to form the gate electrode 232. Subsequently, the source / drain regions 222 are formed by implanting impurities into both polysilicon layer patterns 220 of the gate electrode 232.

Next, an interlayer insulating film 240 having a predetermined thickness is formed on the entire surface. Here, the interlayer insulating film 240 is formed using a silicon oxide film.

Next, the interlayer insulating layer 240 and the gate insulating layer 230 are etched by a photolithography process to form contact holes (not shown) that expose the source / drain regions 222.

Next, an electrode material is formed on the entire surface including the contact hole, and the source / drain electrodes 250 and 252 connected to the source / drain regions 222 are formed by etching the electrode material by a photolithography process. do. In this case, as the electrode material, molybdenum tungsten (MoW) or aluminum-neodymium (Al-Nd) may be used.

Thereafter, the protective film 260 is formed over the entire surface by using an inorganic insulating film such as a silicon nitride film having a predetermined thickness.

Next, a first via contact hole (not shown) is formed to expose any one of the source / drain electrodes 250 and 252 by a photolithography process.

Next, a planarization film 270 is formed over the entire surface.

Subsequently, a second via contact hole (not shown) is formed through the first via contact hole to expose one of the source / drain electrodes 250 and 252 through a photolithography process.

Next, a reflective film (not shown) is formed over the entire surface. In this case, the reflective film is formed using an ACX film which is an alloy material of aluminum and nickel. At this time, the reflecting film contains less than 3% nickel, and if the thickness is less than 500 광, the light may penetrate the reflecting film.

Then, the surface of the reflective film is cleaned. At this time, the washing step is performed by using the deionized water. At this time, the washing step is carried out for 30 to 120 seconds using deionized water. In the cleaning process, the surface of the ACX film, which is the reflective film, is oxidized by deionized water to form a protective film 281 on the surface of the reflective film. The protective film 281 is an oxide of the reflective film, and is formed to have a thickness of 10 to 100 kPa, which is such that the luminous efficiency is not lowered. The cleaning process may be any method including a spin method.

Thereafter, the reflective film is etched by a photolithography process to form the reflective film pattern 280 in the emission region.

Next, a pixel electrode metal layer (not shown) is formed over the entire surface. In this case, the pixel electrode metal layer is formed to a thickness of 50 to 200 kV using a transparent metal layer such as ITO. In the above structure, it is preferable to form the metal layer for the pixel electrode as thin as a top emission type organic electroluminescent device using a resonance phenomenon of light.

Next, the pixel electrode metal layer is etched by a photolithography process and connected to any one of the source / drain electrodes 250 and 252, for example, the drain electrode 252, through the second via contact hole. Form 282.

Subsequently, a pixel definition layer (not shown) is formed over the entire surface. In this case, the pixel definition layer is an organic insulating layer, and a material selected from the group consisting of polyimide, benzocyclobutene series resin, phenol resin, and acrylate. It can be formed as. The thin film as described above can be patterned by a photolithography process performed by an exposure and development process.

Next, the pixel definition layer is patterned by a photolithography process to form a pixel definition layer pattern 290 exposing a light emitting region. Referring to FIG. 5, the protective film 281 formed on the reflective film pattern 280 may not penetrate the developer used in the development process of the pixel definition layer during the photographing process. This is because the protective film 281 has a higher film quality than the pixel electrode 280.

Next, an organic layer including at least a light emitting layer 292 is formed on the surface of the pixel electrode 282 exposed by the pixel defining layer pattern 290.

Thereafter, a counter electrode (not shown) is formed over the entire surface. The counter electrode is formed using a transparent metal layer.

FIG. 6 is a photograph of an organic light emitting display device according to an exemplary embodiment of the present invention, in which a protective film is formed on a surface of a reflective film to show that a developer does not affect the reflective film. That is, it is proved that the protective film prevents penetration of the developer to prevent corrosion of the reflective film.

According to the embodiment of the present invention as described above, in the case of using the aluminum alloy ACX as a reflective film, after forming a reflective film with the ACX and performing a cleaning process using deionized water to form a protective film on the surface of the reflective film As a result, the ACX is prevented from being damaged by the developing solution of the subsequent pixel definition layer, thereby preventing the optical properties from deteriorating and thereby improving the yield.

Claims (16)

A thin film transistor including a gate electrode and a source / drain electrode on the transparent insulating substrate; A reflective film pattern provided in an upper emission area of the insulating film including a via contact hole on the transparent insulating substrate and including a protective film on an upper side thereof; A pixel electrode connected to any one of the source / drain electrodes through the via contact hole on the light emitting region of the transparent insulating substrate; An organic film layer provided in a light emitting area above the pixel electrode and having at least a light emitting layer; An organic electroluminescent device comprising a counter electrode provided above the organic film layer. The method of claim 1, The reflective film pattern is an organic electroluminescent device, characterized in that the aluminum and nickel alloy. The method of claim 2, The content of nickel is less than 3% of the organic electroluminescent device. The method of claim 1, The thickness of the said reflective film is 500-3000 micrometers, The organic electroluminescent element characterized by the above-mentioned. The method of claim 1, The protective film is an organic electroluminescent device, characterized in that the oxide of the reflective film. The method of claim 5, The thickness of the protective film is an organic electroluminescent device, characterized in that 10 to 100 Å. The method of claim 1, The pixel electrode has a thickness of 50 to 200 kHz. Forming an insulating film on the transparent insulating substrate having a thin film transistor including a gate electrode and a source / drain electrode; Forming a via contact hole to expose any one of the source / drain electrodes by etching the insulating layer by a photolithography process; Forming a reflective film on the entire surface; Washing the reflective film to form a protective film on the reflective film surface; Forming a reflective film pattern on the light emitting region of the insulating film of the transparent insulating substrate by etching the protective film and the reflective film by a photolithography process; Forming a pixel electrode connected to any one of the source / drain electrodes through the via contact hole; Forming a pixel definition film pattern exposing the light emitting area over the entire surface; Forming an organic film including at least a light emitting layer in a light emitting region of the pixel electrode; A method of manufacturing an organic electroluminescent device comprising the step of forming a counter electrode on the entire surface. The method of claim 8, The reflective film is a method of manufacturing an organic EL device, characterized in that formed of aluminum and nickel alloy. The method of claim 9, The content of the nickel is less than 3% method for producing an organic electroluminescent device. The method of claim 8, The thickness of the said reflective film is 500-3000 micrometers, The manufacturing method of the organic electroluminescent element characterized by the above-mentioned. The method of claim 8, The cleaning step is a method of manufacturing an organic electroluminescent device, characterized in that carried out using deionized water. The method of claim 8, The cleaning process is a method of manufacturing an organic electroluminescent device, characterized in that performed for 30 to 120 seconds. The method of claim 8, The protective film is an organic electroluminescent device manufacturing method, characterized in that the oxide of the reflective film. The method of claim 8, The protective film has a thickness of 10 to 100 kPa, The manufacturing method of the organic electroluminescent element characterized by the above-mentioned. The method of claim 8, The thickness of the pixel electrode is 50 to 200 Å The manufacturing method of the organic electroluminescent display device characterized by the above-mentioned.

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