Organic light emitting display apparatus and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-2016351652-A1
Application number	US-201514985026-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	May 28, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

An organic light emitting display device includes a thin film transistor (TFT) including a gate electrode and a source electrode. An anode electrode is disposed on the TFT, and a cathode electrode disposed on an organic emission layer is connected to an auxiliary electrode which is disposed on a same layer on which the anode electrode is disposed. A signal pad disposed in a pad area of a substrate is disposed on a same layer on which the gate electrode is disposed in an active area of the substrate. A pad electrode disposed on the signal pad is connected to the signal pad through a contact hole.

First claim

1 . An organic light emitting display apparatus, comprising:
a substrate including an active area and a pad area; a thin film transistor (TFT) including a gate electrode and a source electrode that are disposed in the active area of the substrate; an anode electrode disposed on the TFT; an organic emission layer disposed on the anode electrode; a cathode electrode disposed on the organic emission layer; an auxiliary electrode disposed on a same layer on which the anode electrode is disposed, the auxiliary electrode being connected to the cathode electrode; a signal pad disposed in the pad area of the substrate and on a same layer on which the gate electrode is disposed; and a pad electrode disposed in the pad area and connected to the signal pad through a contact hole, wherein the pad electrode is disposed on a same layer on which the source electrode is disposed, and wherein the pad electrode disposed in the pad area is externally exposed.

2 . The organic light emitting display apparatus of claim 1 , wherein the pad electrode is formed of a material having a lower oxidation rate than that of the signal pad.

3 . The organic light emitting display apparatus of claim 1 , wherein
the source electrode comprises a lower source electrode and an upper source electrode, and the pad electrode is a single layer formed of a same material as that of the lower source electrode.

4 . The organic light emitting display apparatus of claim 1 , further comprising a passivation layer disposed on the pad electrode, the passivation layer including a contact hole that externally exposes the pad electrode.

5 . The organic light emitting display apparatus of claim 1 , wherein an upper surface of the pad electrode is exposed to an outside.

6 . The organic light emitting display apparatus of claim 1 , wherein
the signal pad comprises a lower signal pad and an upper signal pad, an oxidation rate of the lower signal pad is lower than an oxidation rate of the upper signal pad, and a resistance of the upper signal pad is lower than a resistance of the lower signal pad.

7 . The organic light emitting display apparatus of claim 1 , wherein the auxiliary electrode comprises:
a first auxiliary electrode; and a second auxiliary electrode disposed on a top and a side surface of the first auxiliary electrode.

8 . The organic light emitting display apparatus of claim 7 , wherein
the first auxiliary electrode comprises a first lower auxiliary electrode and a first upper auxiliary electrode, and the second auxiliary electrode comprises a second lower auxiliary electrode, a second center auxiliary electrode, and a second upper auxiliary electrode.

9 . The organic light emitting display apparatus of claim 8 , wherein
an oxidation rate of the first lower auxiliary electrode is lower than an oxidation rate of the first upper auxiliary electrode, a resistance of the first upper auxiliary electrode is lower than a resistance of the first lower auxiliary electrode, an oxidation rate of each of the second lower auxiliary electrode and the second upper auxiliary electrode is lower than an oxidation rate of the second center auxiliary electrode, and a resistance of the second center auxiliary electrode is lower than a resistance of each of the second lower auxiliary electrode and the second upper auxiliary electrode.

10 . The organic light emitting display apparatus of claim 1 , further comprising:
a bank disposed on one side and the other side of the auxiliary electrode; and a partition wall disposed on the auxiliary electrode and being separated from the bank, wherein the cathode electrode is connected to the auxiliary electrode through a separation space between the bank and the partition wall.

11 . The organic light emitting display apparatus of claim 1 , wherein the gate electrode is disposed between a gate insulation layer and an interlayer dielectric formed on the gate electrode.

12 . The organic light emitting display apparatus of claim 1 , wherein the source electrode is disposed between an interlayer dielectric formed on the gate electrode and a passivation layer formed on the source electrode.

13 . A method of manufacturing an organic light emitting display apparatus, the method comprising:
forming a gate electrode and a signal pad on a substrate that includes an active area and a pad area; forming an interlayer dielectric on the gate electrode and the signal pad and forming a source electrode and a pad electrode on the interlayer dielectric; forming a passivation layer on the source electrode and the pad electrode; forming an anode electrode and an auxiliary electrode separated from the anode electrode on the passivation layer; and removing at least a portion of the passivation layer formed on the pad electrode, for externally exposing the pad electrode disposed in the pad area.

14 . The method of claim 13 , further comprising forming a planarization layer between the passivation layer and the anode electrode.

15 . The method of claim 13 , wherein the fanning of the source electrode and the pad electrode comprises:
forming a lower source electrode and an upper source electrode and forming a lower pad electrode and an upper pad electrode by using a photoresist pattern as a mask; ashing the photoresist pattern to remove the photoresist pattern on the pad electrode; and etching the upper pad electrode.

16 . The method of claim 13 , wherein the removing of the at least a portion of the passivation layer comprises:
forming a photoresist pattern on the anode electrode, the auxiliary electrode, and the passivation layer; forming a contact hole for externally exposing the pad electrode by removing a predetermined region of the passivation layer by using the photoresist pattern as a mask; and after the forming of the contact hole, forming a bank by using the photoresist pattern which is left after ashing the photoresist pattern.

17 . The method of claim 13 , wherein the forming of the anode electrode comprises forming a first anode electrode and a second anode electrode, and
the forming the auxiliary electrode comprises forming a first auxiliary electrode and a second auxiliary electrode, and wherein the second anode electrode covers a top and a side surface of the first anode electrode, and the second auxiliary electrode covers a top and a side surface of the first auxiliary electrode.

18 . The method of claim 17 , further comprising:
after the forming of the second anode electrode and the second auxiliary electrode and the removing of the at least a portion of the passivation layer, forming a bank on one side and the other side of the second auxiliary electrode; forming an organic emission layer on the second anode electrode; and forming a cathode electrode, connected to the second auxiliary electrode, on the organic emission layer.

19 . The organic light emitting display apparatus of claim 12 , wherein a top surface of the pad electrode is not covered by a layer.

20 . The method of claim 13 , wherein a top surface of the pad electrode is not covered by a layer.

Assignees

• Lg Display Co Ltd

Inventors

• Kim Sejune
• Lee Joonsuk
• Lee Sojung
• Jang Jin-Hee
• Im Jonghyeok
• Lee Jaesung

Classifications

• H10K59/87

  Passivation; Containers; Encapsulations · CPC title

• H10K59/80522

  combined with auxiliary electrodes · CPC title

• H10K59/80518

  Reflective anodes, e.g. ITO combined with thick metallic layers · CPC title

• H10K59/1315

  comprising structures specially adapted for lowering the resistance · CPC title

• H10K59/124 Primary

  Insulating layers formed between TFT elements and OLED elements · CPC title