KR20130028307A - Top emitting organic light emitting diode - Google Patents

Abstract

PURPOSE: An organic light emitting diode is provided to reduce process time and cost by omitting a planarization process and an insulation progress. CONSTITUTION: A lower electrode is formed in one surface of a substrate. An organic light emitting layer is formed on the lower electrode. An upper electrode is formed on the organic light emitting layer. An upper electrode pad is formed on the upper electrode. The upper electrode pad covers a part of the light emitting area of the organic light emitting layer. [Reference numerals] (AA) Upper electrode pad; (BB) Upper electrode; (CC) Organic light emitting layer(active layer); (DD) Lower electrode; (EE) Opaque conductive substrate; (FF) Lower electrode pad; (GG) Light emitting side; (HH) Upper electrode pad

Description

Top-emitting organic light emitting diode {TOP EMITTING ORGANIC LIGHT EMITTING DIODE}

The present invention relates to a top-emitting organic light emitting diode (hereinafter, referred to as a 'front-emitting OLED'), and more specifically, no planarization process or insulation process is required in the manufacturing process, and a space for a separate upper electrode pad is required. The present invention relates to a top-emitting OLED having a light emitting area which is increased, thereby improving luminous efficiency.

Recently, the importance of top-emitting OLEDs is increasing as OLEDs are spotlighted as large-area OLEDs, mass production, and lighting sources. Accordingly, various structures for implementing a top-emitting OLED have been proposed.

Opaque conductive substrates, such as steel substrates, are frequently used in the manufacture of a double light emitting OLED. However, because the surface roughness of the steel substrate used is not suitable for manufacturing the OLED as it is, the planarization process is essential. In addition, as shown in Figures 4a and 4b, in order to prevent a short between the upper electrode and the lower electrode, an insulating process for forming an insulating layer therebetween is necessary, so the conventional method of manufacturing a top-emitting OLED for lighting is manufactured It has the disadvantage of being costly and time consuming.

In addition, as shown in FIG. 4C, a separate space in which the upper electrode pad or the lower electrode pad is located is required, which leads to a reduction in the light emitting area, thereby lowering the luminous efficiency.

The present invention is to solve the problems of the conventional top-emitting OLED as described above, the main problem of the present invention can be driven without using a separate planarization process or insulation process, the front surface can greatly reduce the manufacturing cost It is to provide a light emitting OLED.

In addition, another object of the present invention is to provide a top-emitting OLED that can improve the luminous efficiency by not using a separate space for the electrode pad.

In order to achieve the above object, the present invention, an opaque conductive substrate, a lower electrode formed on one surface of the substrate, an organic light emitting layer formed on the lower electrode, an upper electrode formed on the organic light emitting layer, and the upper electrode And an upper electrode pad formed at the upper electrode pad, wherein the upper electrode pad is formed to cover a part of an emission area of the organic light emitting layer.

The top emission type organic light emitting diode according to the present invention is formed in such a manner that the upper electrode pad partially covers the organic light emitting layer, and since there is no possibility of a short between the upper and lower electrodes, the insulating process can be eliminated.

In addition, in the top-emitting organic light emitting diode according to the present invention, the opaque conductive substrate has a surface roughness of the element formation surface when observed in a scan range of 10 μm × 10 μm using AFM (Atomic Force Microscope). It is preferable that <Rms <100nm, 0 <Rp-v <1000nm. This is because when the surface roughness of the conductive substrate deviates from the above value, it is difficult to form the light emitting device without planarization of the substrate.

In addition, in the top emission organic light emitting diode according to the present invention, the opaque conductive substrate may serve as a lower electrode pad. In this case, the process of forming the lower electrode pad can be eliminated, thereby reducing the manufacturing cost and time.

In addition, in the top emission type organic light emitting diode according to the present invention, a lower electrode pad may be further formed on the opposite side of the element formation surface of the opaque conductive substrate.

Further, in the top-emitting organic light emitting diode according to the present invention, the opaque conductive substrate is Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, Co, In, Mn, Si, Ta, Ti, Sn, Pb, V, Ru, Ir, Zr, Rh, Mg, Invar or SUS (Seel Use Stainless) and their alloys, or nanowires, metal grids, or conductive materials of these metals It may be made of one or more selected from the group consisting of polymers.

In the top emission type organic light emitting diode according to the present invention, the upper electrode pad or the lower electrode pad may be formed of Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, It may be made of one or more metals or alloys thereof selected from the group consisting of Co, In, Mn, Ta, Ti, Sn, Zn, Pb, V, Ru, Ir, Zr, Rh, Mg, Invar and stainless steel. .

Further, in the top emission organic light emitting diode according to the present invention, an auxiliary electrode may be formed between the upper electrode and the upper electrode pad.

In addition, in the top emission organic light emitting diode according to the present invention, an auxiliary electrode may be further formed on the upper electrode pad.

In addition, the present invention as a means for solving the other problem of the present invention, an opaque conductive substrate, a lower electrode formed on one surface of the substrate, an organic light emitting layer formed on the lower electrode, the upper formed on the organic light emitting layer And an auxiliary electrode formed on the upper electrode, wherein the auxiliary electrode is formed to cover a part of an emission area of the organic light emitting layer, and does not form an upper electrode pad on the auxiliary electrode, It provides a top-emitting organic light emitting diode utilizing the upper electrode pad. When the upper electrode pad is not formed in this manner, the light emitting area can be enlarged, thereby improving the light emitting efficiency.

The top-emitting OLED according to the present invention does not require a separate planarization process or an insulation process and can significantly reduce the process cost and time since the device can be manufactured using only a metal mask.

The top-emitting OLED according to the present invention can obtain the effect of maximizing the emission area because no separate electrode pad space is required.

1 is a cross-sectional view and a plan view showing a structure of a top-emitting OLED according to a first embodiment of the present invention.
2 is a cross-sectional view showing the structure of a top-emitting OLED according to a second embodiment of the present invention.
3 is a cross-sectional view and a plan view showing a structure of a top-emitting OLED according to a third embodiment of the present invention.
4A to 4C show the structure of a conventional top-emitting OLED.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention illustrated in the following may be modified in many different forms, the scope of the present invention is not limited to the embodiments described in the following. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. It is also to be understood that the size or thickness of the films or regions in the accompanying drawings is exaggerated for clarity of specification.

[First Embodiment]

1 is a cross-sectional view (top side) and a top view (bottom side) for illustrating the structure of a top-emitting OLED according to a first embodiment of the present invention.

As shown in FIG. 1, the vertical top-emitting OLED according to the first embodiment of the present invention includes an opaque conductive substrate having a lower electrode pad formed thereon, a lower electrode formed on the substrate, and a lower electrode formed on the lower electrode. The organic light emitting layer is formed, an upper electrode formed on the organic light emitting layer, and an upper electrode pad formed on the upper electrode.

As the opaque conductive substrate, when the surface roughness of the element formation surface is observed in a scan range of 10 μm × 10 μm using AFM (Atomic Force Microscope), 0 <Rms <100nm and 0 <Rp-v <1000nm are used. do. In this case, the top-emitting OLED according to the first embodiment of the present invention is formed by separating and then forming a conductive metal thin film on the mother substrate whose surface roughness is adjusted to the numerical range, so that the surface roughness of the mother substrate is almost intact. A light emitting element is formed on the separation surface. As a result, a separate planarization layer may not be formed or the polishing process may be performed on the conductive substrate.

The opaque conductive substrate is Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, Co, In, Mn, Si, Ta, Ti, Sn, Pb, V, Ru, Ir , Zr, Rh, Mg, Invar or SUS (Steel Use Stainless) and alloys thereof, or at least one selected from the group consisting of nanowires, metal grids, or conductive polymers of the above metals. Invar alloys are preferable in consideration of thermal expansion.

The upper electrode pad covers a part of the area of the organic light emitting layer, and is positioned on the organic light emitting layer, and is manufactured by thermal deposition, sputtering, or electron beam deposition through a metal mask.

In addition, the upper electrode pad or the lower electrode pad is Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, Co, In, Mn, Ta, Ti, Sn, Zn , Pb, V, Ru, Ir, Zr, Rh, Mg, Invar and stainless steel can be made of one or more metals or alloys thereof, heat deposition, plating, electron beam deposition, heat adhesion It is formed in the form and the like.

Other materials, such as an organic light emitting layer, use a well-known material.

In addition, the upper electrode pad is formed at an upper portion of the light emitting surface to cover a part of the light emitting surface, as shown below in FIG. 1. Accordingly, electrical short between the upper electrode and the lower electrode cannot occur, and there is no need to form the insulating layer formed in the conventional top-emitting OLED.

In addition, as compared with FIG. 4, in the case of the top-emitting OLED according to the first embodiment of the present invention, since there is no separate electrode pad space, an effect of maximizing the emission area can also be obtained.

[Second Embodiment]

2 is a cross-sectional view showing the structure of a top-emitting OLED according to a second embodiment of the present invention.

As shown in FIG. 2, the vertical top-emitting OLED according to the second embodiment of the present invention includes an opaque conductive substrate, a lower electrode formed on the substrate, an organic light emitting layer formed on the lower electrode, and the organic And an upper electrode formed on the light emitting layer and an upper electrode pad formed on the upper electrode.

That is, the top-emitting OLED according to the second embodiment of the present invention is used without forming the lower electrode pad on the opaque conductive substrate, and the rest is the same as the first embodiment.

[Third Embodiment]

3 is a cross-sectional view and a plan view showing a structure of a top-emitting OLED according to a third embodiment of the present invention.

As shown in FIG. 3, the vertical top-emitting OLED according to the third embodiment of the present invention includes an opaque conductive substrate having a lower electrode pad formed thereon, a lower electrode formed on the substrate, and a lower electrode formed on the lower electrode. The organic light emitting layer is formed, an upper electrode formed on the organic light emitting layer, an auxiliary electrode formed on the upper electrode, and an upper electrode pad on the auxiliary electrode.

That is, the top-emitting OLED according to the third embodiment of the present invention is to facilitate diffusion of current by forming an auxiliary electrode on the upper electrode and the upper electrode pad.

In addition, the auxiliary electrode may be formed on the electrode pad, and when the auxiliary electrode is formed, the upper electrode pad may not be used.

Claims (9)

An opaque conductive substrate,
A lower electrode formed on one surface of the substrate;
An organic emission layer formed on the lower electrode;
An upper electrode formed on the organic light emitting layer;
An upper electrode pad formed on the upper electrode,
The upper electrode pad is a top emission type organic light emitting diode formed to cover a portion of the light emitting area of the organic light emitting layer. The method of claim 1,
The opaque conductive substrate has a surface roughness of 0 <Rms <100nm and 0 <Rp-v <1000nm when the surface roughness of the device formation surface is observed in a scan range of 10 μm × 10 μm using AFM (Atomic Force Microscope) Emission type organic light emitting diode. The method of claim 1,
The top emission organic light emitting diode of which the opaque conductive substrate serves as a lower electrode pad. The method of claim 1,
And a lower electrode pad formed on the opposite side of the element formation surface of the opaque conductive substrate. The method of claim 1,
The opaque conductive substrate is Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, Co, In, Mn, Si, Ta, Ti, Sn, Pb, V, Ru, Ir , Zr, Rh, Mg, Invar or Stainless Steel (Stainless Use Stainless) and alloys thereof, or one or more selected from the group consisting of nanowires, metal grids, or conductive polymers of the above metals Organic light emitting diode. The method of claim 4, wherein
The upper electrode pad or the lower electrode pad may include Fe, Ag, Au, Cu, Cr, W, Al, Mo, Zn, Ni, Pt, Pd, Co, In, Mn, Ta, Ti, Sn, Zn, Pb And V, Ru, Ir, Zr, Rh, Mg, Invar, and stainless steel, at least one metal selected from the group or alloys thereof. The method of claim 1,
A top emission type organic light emitting diode having an auxiliary electrode formed between the upper electrode and the upper electrode pad. The method of claim 1,
A top emission organic light emitting diode having an auxiliary electrode formed on the upper electrode pad. An opaque conductive substrate,
A lower electrode formed on one surface of the substrate;
An organic emission layer formed on the lower electrode;
An upper electrode formed on the organic light emitting layer;
An auxiliary electrode formed on the upper electrode;
The auxiliary electrode is formed to cover a part of the light emitting area of the organic light emitting layer,
A top emission type organic light emitting diode using the auxiliary electrode as an upper electrode pad without forming an upper electrode pad on the auxiliary electrode.

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