KR20130033093A - Organic light emitting diode(oled) and method for manufacturing the same - Google Patents

Abstract

The present invention relates to an organic electroluminescent device and a method for manufacturing the same, which can be easily and easily manufactured by improving an opening ratio by preventing a non-light emitting region such as an insulating film from being formed on the auxiliary electrode. The electroluminescent device includes a substrate; A wiring electrode formed on one surface of the substrate to supply main power; An auxiliary electrode formed in a specific pattern on one surface of the substrate and connected to the wiring electrode and having an inclined surface inclined at an angle with respect to the substrate surface at both edges thereof; A first electrode applied to cover at least a portion of the wiring electrode and the auxiliary electrode; An organic light emitting layer made of an organic material coated on the first electrode; It characterized in that it comprises a second electrode formed on the organic light emitting layer.

Description

Organic Light Emitting Diode (OLED) and Method for Manufacturing the Same}

The present invention relates to an organic light emitting diode (OLED) and a method of manufacturing the same, and more particularly, to an organic light emitting diode having an auxiliary electrode for reducing luminance unevenness of the organic light emitting diode (OLED); The manufacturing method is related.

An organic light emitting diode (OLED) is a self-made method using electrons and holes injected through an anode and a cathode into an organic thin film to recombine to form excitons, and light of a specific wavelength is generated by energy from the formed excitons. It is a light emitting display device.

The organic light emitting device is a self-luminous device that does not require an additional surface light source such as a backlight unit, and has an advantage of wide viewing angle, fast response speed, and thin thickness.

The organic light emitting diode OLED is a current device, and the required current amount increases proportionally according to the panel size and the required brightness, and the voltage drop (IR drop) in the wiring is remarkable, resulting in unbalanced luminance. In particular, since the resistance of a transparent electrode (eg, ITO metal) used as an anode of an organic light emitting device is several Ω / □ higher than that of a general metal, it is an aid to reduce luminance unevenness when the panel size is several cm or more. It requires an electrode.

In addition, a wiring electrode for supplying power to the anode or cathode layer is disposed around the light emitting portion. A low resistance metal is used to minimize the voltage drop even when forming the wiring electrode.

These wiring electrodes and auxiliary electrodes are formed in a grid pattern while crossing the substrate surface of the device horizontally and vertically, and conventionally, aluminum (Al), silver (Ag), chromium (Cr), and aluminum-neodymium (AlNd). ) And metal such as aluminum / molybdenum (Al / Mo) were formed by sputtering, and then patterned by photolithography to form wiring and auxiliary electrodes.

1 and 2 illustrate an example of a conventional organic light emitting diode, and the organic light emitting diode OLED includes a substrate 1, a wiring electrode 2 and an auxiliary electrode applied to one surface of the substrate 1. (3), a transparent electrode (4) which is an anode applied to cover the wiring electrode (2) and the auxiliary electrode (3), an insulating film (5) which is sequentially applied on the transparent electrode (4) and organic The light emitting layer 6 and the cathode electrode 7, the sealing cover 8 and the sealing material 9 to seal the surface on which the electrode and the organic material are formed so that the electrodes and organics do not come into contact with moisture, oxygen, NOx, etc. in the air. Can be configured.

The organic electroluminescent device has a structure in which the wiring electrode 2 and the auxiliary electrode 3 are formed first, and the transparent electrode 4 is coated thereon. However, the transparent electrode 4 is formed on the substrate 1 first. The wiring electrode 2 and the auxiliary electrode 3 may be formed on the transparent electrode 4.

On the other hand, the conventional organic EL device configured as described above has an organic light emitting layer directly above the auxiliary electrode 3 because the edge portion of the auxiliary electrode 3 and the surface of the substrate 1 have a stepped structure at approximately right angles. In the case of forming 6), the thickness of the organic light emitting layer 6 becomes thin, which causes a problem in that the electric field is concentrated and causes leakage and deterioration.

Accordingly, the organic light emitting layer 6 is formed on the upper side of the auxiliary electrode 3 by forming an insulating film 5 on the upper side of the auxiliary electrode 3, wherein the edge portion of the insulating film 5 is inclined at a predetermined angle or less with respect to the surface of the substrate 1. ) To prevent thickness reduction.

However, when the insulating film 5 is formed in a region wider than the auxiliary electrode 3 above the auxiliary electrode 3 as described above, a problem arises in that the aperture ratio decreases due to the insulating film 5 which is a non-light emitting region.

The present invention is to solve the above problems, an object of the present invention is to improve the aperture ratio by not forming a non-light emitting region such as an insulating film on the auxiliary electrode, an organic field that can be easily and easily manufactured A light emitting device and a method of manufacturing the same are provided.

The present invention for achieving the above object, the substrate; A wiring electrode formed on one surface of the substrate to supply main power; An auxiliary electrode formed on one surface of the substrate in a predetermined pattern and having an inclined surface inclined at an angle with respect to the substrate surface at both edges thereof; A first electrode applied to cover at least a portion of the wiring electrode and the auxiliary electrode; An organic light emitting layer made of an organic material coated on the first electrode; It provides an organic electroluminescent device comprising a second electrode formed on the organic light emitting layer.

According to another aspect of the present invention, a method of manufacturing the organic light emitting device includes (a) disposing a shadow mask having a through hole of a pattern corresponding to the auxiliary electrode pattern in contact with one surface of the substrate or spaced a predetermined distance apart from each other. Wow; (b) forming an auxiliary electrode on one surface of the substrate by vacuum deposition or sputtering; (c) forming a first electrode on one surface of the auxiliary electrode and the substrate; (d) forming an organic light emitting layer formed of an organic material on the first electrode; (e) providing a method of manufacturing an organic light emitting device, comprising forming a second electrode on the organic light emitting layer.

According to the present invention, an inclined surface inclined to a predetermined angle or less with respect to the substrate surface is formed on both edge portions of the auxiliary electrode by vacuum deposition or sputtering using a shadow mask. Therefore, the thickness of the organic light emitting layer can be increased without forming an existing insulating film, and the reduction of the aperture ratio due to the insulating film can be prevented.

In addition, since the auxiliary electrode may be formed by vacuum deposition or sputtering using a shadow mask without performing a complicated process such as photolithography, the manufacturing process may be greatly simplified, and the productivity may be improved.

1 is a longitudinal sectional view schematically showing a structure of a conventional organic light emitting device.
FIG. 2 is a plan view omitting some components of the organic light emitting diode of FIG. 1.
3 is a longitudinal sectional view schematically showing the structure of an organic light emitting display device according to an embodiment of the present invention.
FIG. 4 is a plan view omitting some components of the organic light emitting diode of FIG. 3.
FIG. 5 is a plan view illustrating a shape of a shadow mask for forming the wiring electrode and the auxiliary electrode of the organic light emitting diode of FIG. 3.

Hereinafter, exemplary embodiments of an organic light emitting diode and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

3 and 4 illustrate the structure of an organic light emitting diode according to a preferred embodiment of the present invention. The organic light emitting diode OLED of this embodiment has a substrate 10 and a top surface of the substrate 10. It is applied in a pattern of the wiring electrode 20 is connected to an external power supply to supply the main power and the auxiliary electrode 30, the wiring electrode 20 and the auxiliary electrode (30) connected in a grid form inside the wiring electrode 20 ( 30 and a first electrode 40 applied to cover at least a portion of the 30, the organic light emitting layer 60 and the second electrode 70 are sequentially applied on the first electrode 40, the electrode and the organic material in the air It consists of a configuration including a sealing cover 80 and a sealing material (90) for sealing the surface on which the electrode and the organic material is formed so as not to contact with moisture, oxygen, NOx and the like.

In this embodiment, the first electrode 40 is an ITO transparent electrode, which is an anode, and the second electrode 70 is a cathode, or vice versa.

The wiring electrode 20 is to supply power to each of the first electrode 40 and the second electrode 70, and is formed along four edges of the substrate 10, and the auxiliary electrode 30 is formed of the substrate 10. ) And cross each other in the horizontal and vertical directions to form a grid pattern.

The auxiliary electrode 30 is formed as an inclined surface 31 in which both edge portions are inclined at a predetermined angle or less with respect to the surface of the substrate 10, preferably at an angle of 10 to 30 degrees. When the angle of the inclined surface 31 is greater than 30 degrees, the thickness becomes too thin, and when smaller than 10 degrees, the auxiliary electrode 30 becomes too wide, resulting in low light transmittance of the entire organic light emitting device. . As such, when both edges of the auxiliary electrode 30 are formed at the inclined surface 31 having a predetermined angle or less, the thickness of the organic light emitting layer 60 formed on the auxiliary electrode 30 can be increased, thereby forming an existing insulating film. There is no need to do it.

The wiring electrode 20 and the auxiliary electrode 30 are made of a low resistance metal such as aluminum (Al), silver (Ag), chromium (Cr), aluminum-neodymium (AlNd), aluminum / molybdenum (Al / Mo), or the like. It can be made by using, but in addition it can be made using a variety of arbitrary metals. The wiring electrode 20 and the auxiliary electrode 30 may be physical vapor deposition (PVD), chemical vapor deposition (CVD), or sputtering using a shadow mask 100 as shown in FIG. 5. It is formed in a sputtering manner.

That is, the shadow mask 100 having the through hole 101 of the pattern corresponding to the wiring electrode 20 and the auxiliary electrode 30 is disposed in contact with the upper surface of the substrate 10 or spaced a predetermined distance apart, and vacuum deposition is performed. Alternatively, the wiring electrode 20 and the auxiliary electrode 30 are formed by thermal evaporation or evaporation. At this time, both edge portions of the through hole 101 corresponding to the auxiliary electrode 30 of the shadow mask 100 are formed to be inclined at a predetermined angle with respect to the surface of the substrate 10 so as to be inclined at both edges of the auxiliary electrode 30. 31 is formed.

The angle of the inclined surface 31 of the auxiliary electrode 30 adjusts the inclination angle of the inner peripheral surface of both edges of the through hole 101 of the shadow mask 100 or adjusts the distance between the shadow mask 100 and the surface of the substrate 10. Can be adjusted. As the distance between the shadow mask 100 and the surface of the substrate 10 increases, the inclination becomes lower.

In addition, when the surface state (roughness) of the inclined surface 31 of the auxiliary electrode 30 is not constant in the process of forming the auxiliary electrode 30, after forming the auxiliary electrode 30 to a high temperature annealing (annealing) process Local heat reflow may be performed, or the surface may be treated with plasma or the like to smoothly and uniformly improve the surface of the inclined surface 31.

Meanwhile, after the wiring electrode 20 and the auxiliary electrode 30 are formed on the surface of the substrate 10, the transparent electrode 40 serving as the first electrode to cover the upper side of the wiring electrode 20 and the auxiliary electrode 30 is formed. The organic light emitting layer 60 made of an organic material is coated on the transparent electrode 40, and the cathode electrode 70, which is a second electrode, is coated on the organic light emitting layer 60.

When the transparent electrode 40 and the organic light emitting layer 60 are applied, both edge portions of the auxiliary electrode 30 form an inclined surface 31 inclined at a predetermined angle (for example, 30 degrees or less). The thickness reduction of the organic light emitting layer 60 can be prevented even without forming the insulating film. In addition, it is possible to prevent the reduction of the aperture ratio by the existing insulating film, there is an advantage that the overall manufacturing process of the organic light emitting device is also simplified to improve productivity.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

10: substrate 20: wiring electrode
30: auxiliary electrode 31: inclined surface
40: anode electrode (first electrode) 60: organic light emitting layer
70: cathode electrode (second electrode) 100: shadow mask
101: through hole

Claims (6)

A substrate (10);
A wiring electrode 20 formed on one surface of the substrate 10 to supply main power;
An auxiliary electrode 30 formed on one surface of the substrate 10 in a predetermined pattern and having an inclined surface 31 inclined at an angle with respect to the surface of the substrate 10 at both edges thereof;
A first electrode applied to cover at least a portion of the wiring electrode 2 and the auxiliary electrode 3;
An organic light emitting layer 60 formed of an organic material coated on the first electrode;
An organic light emitting device, characterized in that it comprises a second electrode (70) formed on the organic light emitting layer (60). The organic light emitting device of claim 1, wherein the inclined surface (31) of the auxiliary electrode (30) is formed at an angle of 10 to 30 degrees with respect to the surface of the substrate (10). (a) disposing a shadow mask 100 having a through hole 101 having a pattern corresponding to the pattern of the auxiliary electrode 30 in contact with one surface of the substrate 10 or spaced at a predetermined distance;
(b) forming an auxiliary electrode 30 on one surface of the substrate 10 by physical vapor deposition or chemical vapor deposition;
(c) forming a first electrode 40 on one surface of the auxiliary electrode 30 and the substrate 10;
(d) forming an organic light emitting layer 60 made of an organic material on the first electrode 40;
(e) forming a second electrode (70) on the organic light emitting layer (60). The method of claim 3, further comprising the step of annealing the auxiliary electrode 30 at a high temperature after the step (b) and smoothly improving the surface of the inclined surface 31. Way. The method of claim 3, wherein after the step (b), the surface of the inclined surface 31 is smoothly improved by surface treatment of the auxiliary electrode 30 with plasma. Manufacturing method. The organic field of claim 3, wherein the inclination angle of the inclined surface 31 of the auxiliary electrode 30 is adjusted by adjusting the distance between the shadow mask 100 and the substrate 10 in step (b). Method of manufacturing a light emitting device.

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