KR-20260064066-A - Stretchable organic light-emitting diode

KR20260064066AKR 20260064066 AKR20260064066 AKR 20260064066AKR-20260064066-A

Abstract

The present invention comprises an anode deposited on a substrate, an organic light-emitting diode layer stacked on the anode, and a cathode which is a stretchable transparent electrode stacked on the organic light-emitting diode layer, wherein the cathode comprises a seed layer deposited on the organic light-emitting diode layer and a cathode metal layer deposited on the seed layer, and according to the present invention, the elasticity of the display is secured so that it can be applied to a transparent display.

Inventors

최태영
이병홍
김영범
하인성
류승윤
이창민

Assignees

현대자동차주식회사
기아 주식회사
고려대학교 세종산학협력단

Dates

Publication Date: 20260507
Application Date: 20241031

Claims (11)

Anode deposited on a substrate; Organic light-emitting diode layer stacked on the anode above; It includes a cathode which is a stretchable transparent electrode laminated on the above organic light-emitting layer, and The above cathode is, A seed layer deposited on the above organic light-emitting layer; and A cathode metal layer deposited on the seed layer, Stretchable organic light-emitting diode.
In claim 1, The above seed layer is a first seed layer deposited on the organic light-emitting layer; It includes a second seed layer deposited on the first seed layer, and The above cathode metal layer is characterized by being deposited on the second seed layer. Stretchable organic light-emitting diode.
In claim 2, The first seed layer is characterized by being a ZnS material, Stretchable organic light-emitting diode.
In claim 3, The above second seed layer is characterized by being made of Ca material, Stretchable organic light-emitting diode.
In claim 3, The above second seed layer is characterized by being made of Li₂CO₃ material , Stretchable organic light-emitting diode.
In claim 4 or claim 5, A coating layer of ZnS material formed on the above cathode metal layer, further comprising Stretchable organic light-emitting diode.
In claim 4 or claim 5, The above anode is characterized as being an OMO (Oxide-Metal-Oxide) anode in which an anode metal layer is formed on two oxide layers. Stretchable organic light-emitting diode.
In claim 1, The above seed layer has a thickness of 1 nm to 10 nm, and The above cathode metal layer is characterized by having a thickness of 5 nm to 20 nm, Stretchable organic light-emitting diode.
In claim 1, The above seed layer is characterized by being made of Ca or Li₂CO₃ material , Stretchable organic light-emitting diode.
In claim 9, A coating layer of NPB (N,N'-diphenly-N,N'-bis(1,1'-biphenyl)-4,4'-diamine) material formed on the above cathode metal layer, further comprising Stretchable organic light-emitting diode.
In claim 9, The above anode is characterized as being an OMO (Oxide-Metal-Oxide) anode in which an anode metal layer is formed on two oxide layers. Stretchable organic light-emitting diode.

Description

Stretchable organic light-emitting diode The present invention relates to an OLED device applicable to a display by applying a stretchable transparent electrode element. Research on the free form factor, the ultimate goal of displays, has been actively ongoing since the past. To realize displays applicable to free-form surfaces, it is necessary to secure stretchable transparent electrodes. However, ITO (Indium tin oxide), which is currently used as a transparent electrode, is difficult to use as a stretchable device. In other words, although ITO, a commonly used transparent electrode, has high transmittance, its resistance increases sharply when strain is applied and cracks may occur, making it difficult to apply as a stretchable device. In addition, when using a thin metal to ensure transmittance of the cathode electrode, transmittance increases, but resistance is high due to island growth, and film formation is not smooth. (Island growth) The matters described in the background technology above are intended to aid in understanding the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. FIG. 1 is a schematic representation of a stretchable organic light-emitting diode according to a first embodiment of the present invention, and FIG. 2 is a detailed illustration of a stretchable organic light-emitting diode according to a first embodiment of the present invention. Figure 3 is a schematic diagram of electrode formation using a seed layer. Figure 4 shows the transmittance according to the first embodiment of the present invention. Figure 5 shows an organic light-emitting diode according to a comparative example, and Figure 6 shows a metal deposition process. FIG. 7 illustrates a stretchable organic light-emitting diode according to a second embodiment of the present invention. FIG. 8 shows the metal deposition process of a stretchable organic light-emitting diode according to a second embodiment of the present invention, and FIG. 9 shows the transmittance according to the second embodiment. FIG. 10 shows a stretchable organic light-emitting diode according to a third embodiment of the present invention, and FIG. 11 shows the transmittance according to the third embodiment. Figure 12 is the device life evaluation of the third embodiment, Figure 13 is the current density, and Figure 14 is XPS analysis data. FIGS. 15 to 20 sequentially illustrate the stretching test process, and FIG. 21 is a photograph of the test result. Figure 22 shows the change in frequency after the stretching test of the organic light-emitting diode of Figure 2, Figure 23 shows the transmittance, and Figure 24 shows the change in efficiency. In order to fully understand the present invention, the operational advantages of the present invention, and the objectives achieved by the implementation of the present invention, reference must be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described therein. In describing preferred embodiments of the present invention, known technologies or repetitive descriptions that may unnecessarily obscure the essence of the invention will be shortened or omitted. FIG. 1 is a schematic diagram of a stretchable organic light-emitting diode according to a first embodiment of the present invention, and FIG. 2 is a detailed illustration of a stretchable organic light-emitting diode according to a first embodiment of the present invention. FIG. 3 is a schematic diagram of electrode formation using a seed layer, and FIG. 4 shows the transmittance according to a first embodiment of the present invention. Hereinafter, a stretchable organic light-emitting element according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4. The present invention is an organic light-emitting diode in which an anode (110), an organic light-emitting layer (130, OLED layer) made of an organic compound, and a cathode (120) are sequentially stacked on a stretchable polymer substrate, and light is emitted from the organic light-emitting layer when a voltage is applied to the anode and the cathode. Furthermore, by including a stretchable transparent electrode, the organic light-emitting diode is capable of being stretched while satisfying transmittance, and is applicable to a free-form display. That is, by utilizing a seed layer (ZnS, Ca, Li₂CO₃ ) to increase surface energy and forming a thin film electrode on top , a transparent and stretchable electrode was realized. An OMO (Oxide-Metal-Oxide) anode is formed by stacking a metal layer and an oxide layer, and as shown in the example, MoO3 , Au, and MoO3 can be sequentially stacked and can have thicknesses of 15 nm, 7 nm, and 5 nm sequentially. And, a stretchable cathode (120) including a cathode metal layer (121) may be deposited on the top, and the cathode metal layer (121) may be Ag, etc.