US-20260126867-A1 - Display Apparatus Having a Connecting Electrode which Crosses a Bending Area

US20260126867A1US 20260126867 A1US20260126867 A1US 20260126867A1US-20260126867-A1

Abstract

A display apparatus having a connection electrode which crosses a bending area may be provided. The connection electrode may be disposed on a device substrate including a bending area between a display area and a pad area. The connection electrode may connect the display area and the pad area across the bending area. The connection electrode may have a stacked structure of the lower connecting electrode and the upper connecting electrode. A light-emitting device, an encapsulating element and a touch electrode may be sequentially stacked on the display area of the device substrate. The upper connecting electrode may include the same material as the touch electrode. Thus, in the display apparatus, the disconnection of the connection electrode due to bending stress and external impact may be reduced.

Inventors

Jeong-Oh Kim
Seung-Chan Choi
Jei-Hyun LEE

Assignees

LG DISPLAY CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20260105
Priority Date: 20191231

Claims (10)

1 . A display apparatus comprising: a device substrate including a display area and a bending area; a first thin film transistor including a first semiconductor film, a first gate electrode, a first source electrode, and a first drain electrode in the display area; a second thin film transistor including a second semiconductor film, a second gate electrode, a second source electrode, and a second drain electrode in the display area; a light-emitting device on the display area of the device substrate; a passivation layer positioned between the second gate electrode and the second source electrode and positioned between the second gate electrode and the second drain electrode in the display area; a first over-coat layer positioned on the passivation layer and positioned between the second source electrode and the light-emitting device and between the second drain electrode and the light-emitting device in the display area; a second over-coat layer between the first over-coat layer and the light-emitting device in the display area; an intermediate contact electrode positioned between the first over-coat layer and the second over-coat layer in the display area, and the light-emitting device and the first thin film transistor being electrically connected to each other through the intermediate contact electrode; a lower connecting electrode on the bending area on the device substrate, the lower connecting electrode crossing the bending area; and a crack preventing layer on the lower connecting electrode in the bending area, wherein the crack preventing layer includes a same material as the second over-coat layer, the first over-coat layer is further disposed between the crack preventing layer and the device substrate in the bending area, and the lower connecting electrode is between the first over-coat layer and the crack preventing layer.
2 . The display apparatus according to claim 1 , further comprising: a lower insulating layer between the device substrate and the second semiconductor film, wherein the first semiconductor film and the first gate electrode are between the device substrate and the lower insulating layer, and the second semiconductor film and the second gate electrode are between the lower insulating layer and the first over-coat layer.
3 . The display apparatus according to claim 1 , wherein the second semiconductor film is positioned on a different layer from the first semiconductor film in the display area.
4 . The display apparatus according to claim 1 , wherein the first semiconductor film includes a low temperature poly-Si (LTPS) and the second semiconductor film includes a metal oxide.
5 . The display apparatus according to claim 1 , wherein the display area of the device substrate includes a hole peripheral area comprising a substrate hole that penetrates the device substrate.
6 . The display apparatus according to claim 1 , wherein the intermediate contact electrode is electrically connected to the first drain electrode of the first thin film transistor.
7 . The display apparatus according to claim 6 , wherein the lower connecting electrode includes a same material as the intermediate contact electrode.
8 . The display apparatus according to claim 1 , further comprising: an encapsulating element on the light-emitting device; and touch electrodes on the encapsulating element in the display area, wherein the touch electrodes are electrically connected to the lower connecting electrode through one of link lines.
9 . The display apparatus according to claim 8 , wherein the crack preventing layer includes a connection contact hole exposing a portion of the lower connecting electrode, and wherein the one of link lines is electrically connected to the lower connecting electrode through the connection contact hole.
10 . The display apparatus according to claim 8 , further comprising: a cover insulating layer on the touch electrodes in the display area, wherein the cover insulating layer is on the crack preventing layer in the bending area.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/826,798 filed on Sep. 6, 2024, which is a continuation of U.S. patent application Ser. No. 18/081,349 filed on Dec. 14, 2022, which is a continuation of U.S. patent application Ser. No. 17/135,719 filed on Dec. 28, 2020, which claims the priority benefit of Republic of Korea Patent Application No. 10-2019-0180184 filed on Dec. 31, 2019, and Republic of Korea Patent Application No. 10-2020-0162230 filed on Nov. 27, 2020, all of which are hereby incorporated by reference in its entirety. BACKGROUND Field of Technology The present disclosure relates to a display apparatus in which a connection electrode connects a display area and a pad area across a bending area. Discussion of the Related Art Generally, an electronic appliance, such as a monitor, a television (TV), a laptop computer, and a digital camera, includes a display apparatus to display an image. For example, the display apparatus may include at least one light-emitting device. The light-emitting device may emit light displaying a specific color. For example, the light-emitting device may include a light-emitting layer between a first emission electrode and a second emission electrode. The display apparatus may include a bending area between a display area and a pad area. The light-emitting device may be disposed on the display area. A pad to which an external signal is applied may be disposed on the pad area. The device substrate supporting the light-emitting device and the pad may be bent in the bending area. A connection electrode connecting the display area and the pad area may cross the bending area. Thus, in the display apparatus, the connection electrode may be disconnected due to bending stress or external impact. SUMMARY DISCLOSURE Accordingly, the present disclosure is directed to a display apparatus that substantially obviates one or more problems due to limitations and disadvantages of the related art. An object of the present disclosure is to provide a display apparatus preventing the disconnection of the connection electrode due to the bending stress and the external impact. Another object of the present disclosure is to provide a display apparatus in which the display area and the pad area may be stably connected by the connection electrode crossing the bending area. Additional advantages, objects, and features of the disclosure will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the disclosure. The objectives and other advantages of the disclosure may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. To achieve these objects and other advantages and in accordance with the purpose of the disclosure, as embodied and broadly described herein, there is provided a display apparatus including a device substrate. The device substrate includes a display area and a bending area. A light-emitting device is disposed on the display area of the device substrate. An encapsulating element is disposed on the light-emitting device. A touch structure is disposed on the encapsulating element. The touch structure includes a touch electrode. A lower connecting electrode is disposed on the device substrate. The lower connecting electrode crosses the bending area of the device substrate. A crack preventing layer is disposed on the lower connecting electrode. The crack preventing layer includes a region overlapping with the bending area. An upper connecting electrode is disposed on the crack preventing layer. The upper connecting electrode crosses the bending area. The upper connecting electrode includes the same material as the touch electrode. The upper connecting electrode may include a region overlapping with the lower connecting electrode. The crack preventing layer may include a connection contact hole exposing a portion of the lower connecting electrode. The upper connecting electrode may be connected to the lower connecting electrode through the connection contact hole. The connection contact hole may be disposed outside the bending area. Thin film transistors may be disposed between the device substrate and the light-emitting device. The light-emitting device may be connected to one of the thin film transistors by an intermediate contact electrode. The lower connecting electrode may include the same material as the intermediate contact electrode. The upper connecting electrode may be connected to the lower connecting electrode by a middle connecting electrode. The middle connecting electrode may include the same material as a first emission electrode of the light-emitting device. In another aspect, a display apparatus comprises a device substrate. The device substrate includes a bending area disp