US-12622154-B2 - Display device

US12622154B2US 12622154 B2US12622154 B2US 12622154B2US-12622154-B2

Abstract

A display device includes a sub-electrode layer disposed on the substrate while corresponding to at least a part of the non-display area; and banks disposed on the planarization layer in the display area so as to expose at least a part of the anode and disposed on the sub-electrode layer in the non-display area, in which the bank includes a plurality of bank opening portions disposed in the non-display area so as to expose at least a part of the sub-electrode layer, and in which the sub-electrode layer includes oxygen vacancies in an area in which the sub-electrode layer overlaps the plurality of bank opening portions. Therefore, the display device according to the present disclosure, it is possible to provide the display device capable of implementing excellent reliability by suppressing degradation of the pixel caused by oxygen.

Inventors

HeeSuk Pang
MinJoo KANG

Assignees

LG DISPLAY CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20230919
Priority Date: 20221230

Claims (20)

1 . A display device, comprising: a substrate having a display area and a non-display area configured to surround the display area; a thin-film transistor disposed on the substrate while corresponding to the display area; a planarization layer disposed to cover the thin-film transistor; an organic light-emitting element disposed on the planarization layer while corresponding to the display area and including an anode electrically connected to the thin-film transistor, an organic light-emitting layer disposed on the anode, and a cathode disposed on the organic light-emitting layer; a sub-electrode layer disposed on the substrate while corresponding to at least a part of the non-display area; and banks disposed on the planarization layer in the display area so as to expose at least a part of the anode and disposed on the sub-electrode layer in the non-display area, wherein the bank includes a plurality of bank opening portions disposed in the non-display area so as to expose at least a part of the sub-electrode layer, and the sub-electrode layer includes oxygen vacancies in an area in which the sub-electrode layer overlaps the plurality of bank opening portions.
2 . The display device of claim 1 , wherein the planarization layer is disposed in the display area and the non-display area, and the sub-electrode layer is disposed on the planarization layer while corresponding to the at least a part of the non-display area.
3 . The display device of claim 2 , wherein the planarization layer includes a plurality of planarization layer opening portions that respectively overlaps the plurality of bank opening portions in the non-display area, the plurality of planarization layer opening portions each exposes at least a part of a protective layer disposed on the substrate, and the sub-electrode layer is disposed on the planarization layer and the protective layer exposed by the plurality of planarization layer opening portions.
4 . The display device of claim 3 , wherein the sub-electrode layer includes the oxygen vacancies in an area in which the sub-electrode layer overlaps the plurality of planarization layer opening portions.
5 . The display device of claim 1 , wherein the sub-electrode layer includes a first area which overlaps each of the plurality of bank opening portions, and a second area which is the remaining area excluding the first area.
6 . The display device of claim 5 , wherein the first area of the sub-electrode layer is treated with plasma and includes the oxygen vacancies.
7 . The display device of claim 6 , wherein the plasma is argon (Ar) plasma or argon/oxygen (Ar/O 2 ) plasma.
8 . The display device of claim 7 , wherein in the argon/oxygen (Ar/O 2 ) plasma, a flow ratio of argon (Ar) to oxygen (O 2 ) is 7:3 to 9.9:0.1.
9 . The display device of claim 5 , wherein surface resistance of the first area is lower than surface resistance of the second area.
10 . The display device of claim 1 , wherein the sub-electrode layer is made of the same material as the anode.
11 . The display device of claim 1 , wherein the non-display area includes: first and second sides extending in a first direction and configured to face each other; third and fourth sides extending in a second direction perpendicular to the first direction and configured to face each other; a gate drive part disposed on the substrate while corresponding to at least one of the first and second sides; and a data drive part disposed on the substrate while corresponding to the third side, wherein the planarization layer is disposed to cover the gate drive part, and the sub-electrode layer is disposed on the planarization layer while corresponding to the at least one of the first and second sides.
12 . The display device of claim 11 , wherein the gate drive part is disposed on the substrate while corresponding to each of the first and second sides, and the sub-electrode layer is disposed on the planarization layer so as to be elongated along the first and second sides.
13 . The display device of claim 12 , wherein the sub-electrode layer is disposed to surround three sides of an outer periphery of the display area.
14 . The display device of claim 13 , wherein the sub-electrode layer is disposed on the planarization layer while corresponding to at least a part of the fourth side and disposed to be elongated along the fourth side.
15 . The display device of claim 14 , wherein the sub-electrode layer includes a plurality of first opening portions configured to expose at least a part of the planarization layer corresponding to the fourth side, and the first opening portion is elongated in the second direction.
16 . The display device of claim 15 , wherein the bank is disposed to fill the first opening portion.
17 . The display device of claim 14 , wherein the sub-electrode layer includes a plurality of second opening portions configured to expose at least a part of the planarization layer corresponding to the first and second sides, and the plurality of second opening portions is elongated in the first direction.
18 . The display device of claim 17 , wherein the gate drive part includes a plurality of gate drive lines, and at least some of the plurality of second opening portions overlaps at least a part of the gate drive line.
19 . The display device of claim 17 , wherein at least one of the plurality of second opening portions extends to be formed through the sub-electrode layer in the first direction.
20 . The display device of claim 17 , wherein the bank is disposed to fill the second opening portion.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the priority of Korean Patent Application No. 10-2022-0190514 filed on Dec. 30, 2022, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. BACKGROUND Technical Field The present disclosure relates to a display device, and more particularly, to a display device capable of suppressing degradation caused by oxygen introduced from the outside. Discussion of the Related Art Recently, a display field for visually expressing electrical information signals has been rapidly developed as the information age has come in earnest. Therefore, various display devices, which are thin in thickness and light in weight and have excellent performances such as low power consumption, have been developed. Examples of the display devices may include a liquid crystal display device (LCD), an organic light-emitting display device (OLED), and the like. An organic light-emitting display device refers to a display device that autonomously emits light. Unlike a liquid crystal display device, the organic light-emitting display device does not require a separate light source and thus may be manufactured as a lightweight, thin display device. In addition, the organic light-emitting display device is advantageous in terms of power consumption because the organic light-emitting display device operates at a low voltage. Further, the organic light-emitting display device is studied as a next-generation display device because the organic light-emitting display device is excellent in color implementation, a response speed, a viewing angle, and a contrast ratio (CR). In response to market demands for organic light-emitting display devices that are lightweight and thin, the display devices are becoming gradually slimmer, and there is an increasing need to decrease a bezel area (non-display area). Meanwhile, the organic light-emitting display device requires a minimum bezel distance to ensure reliability against outside air such as oxygen, and the minimum bezel distance may be referred to as a reliability bezel. The reliability bezel may be defined as a distance from an end of a substrate to an end of a cathode. As described above, as a need for a slimmer non-display area increases to meet a need for a slimmer display device, the assurance of reliability against outside air is considered as an important issue. SUMMARY When oxygen is introduced through a non-display area of a display device, the oxygen comes into contact with a cathode in a display area through a fine pinhole present in the cathode or through a seam portion formed by foreign materials. For this reason, when the cathode is oxidized, a dark spot occurs, and the dark spot becomes a dead pixel as time passes, which degrades display quality. Accordingly, embodiments of the present disclosure are directed to a display device that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. An aspect of the present disclosure is to provide a display device capable of suppressing or delaying penetration of oxygen, which is introduced from the outside, into a display area, thereby minimizing degradation of a pixel caused by oxygen. Another aspect of the present disclosure is to provide a display device capable of implementing excellent reliability by suppressing degradation of a pixel caused by oxygen without greatly increasing the number of process steps or costs. Additional features and aspects will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts provided herein. Other features and aspects of the inventive concepts may be realized and attained by the structure particularly pointed out in the written description, or derivable therefrom, and the claims hereof as well as the appended drawings. To achieve these and other aspects of the inventive concepts, as embodied and broadly described herein, a display device comprises: a substrate having a display area and a non-display area configured to surround the display area; a thin-film transistor disposed on the substrate while corresponding to the display area; a planarization layer disposed to cover the thin-film transistor; an organic light-emitting element disposed on the planarization layer while corresponding to the display area and including an anode electrically connected to the thin-film transistor, an organic light-emitting layer disposed on the anode, and a cathode disposed on the organic light-emitting layer; a sub-electrode layer disposed on the substrate while corresponding to at least a part of the non-display area; and banks disposed on the planarization layer in the display area so as to expose at least a part of the anode and disposed on the sub-electrode layer in the non-display area, in which the bank includes a plurality of bank opening portions disposed in the no