Electroluminescent display device

Patent metadata

Field	Value
Publication number	US-10811490-B2
Application number	US-201816201700-A
Country	US
Kind code	B2
Filing date	Nov 27, 2018
Priority date	Nov 30, 2017
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

An electroluminescent display device includes a substrate, a bank for defining an emission area on the substrate, an emission layer in the emission area defined by the bank, an electrode on the emission layer and the bank, and a conductive layer on the electrode, wherein the electrode includes a first portion having a relatively small thickness, and a second portion having a relatively large thickness, and the conductive layer is in contact with the first portion of the electrode, and wherein the conductive layer is provided on the electrode, and more particularly, the conductive layer is provided in such a way the conductive layer is in contact with the relatively-thin first portion of the electrode so that it is possible to prevent problems related with a burning phenomenon or wiring disconnection in the first portion of the electrode.

First claim

What is claimed is:

1. An electroluminescent display device including an active area and a dummy area surrounding the active area on a substrate, comprising:
a first electrode provided on the substrate;
a bank covering an end portion of the first electrode and defining an emission area;
an emission layer provided on the first electrode in the emission area;
a second electrode provided on the emission layer and the bank; and
a conductive layer provided on the second electrode,
wherein the second electrode includes a first portion disposed on a lateral surface of the bank, a second portion provided on an upper surface of the bank, and a third portion provided on an upper surface of the emission layer,
wherein the conductive layer includes a first portion disposed on the first portion of the second electrode, and
wherein the conductive layer is disposed only on the bank in the active area, and the conductive layer is disposed on the bank and the emission layer in the dummy area.

2. The electroluminescent display device according to claim 1 , wherein the conductive layer further includes a second portion provided on the second portion of the second electrode.

3. The electroluminescent display device according to claim 2 , further comprising an auxiliary electrode electrically connected with the second electrode through a contact hole in the bank.

4. The electroluminescent display device according to claim 3 , wherein the second electrode further includes a fourth portion extending to the auxiliary electrode along a lateral surface of the contact hole, and the conductive layer includes a third portion disposed on the fourth portion of the second electrode.

5. The electroluminescent display device according to claim 1 , wherein the conductive layer and the second electrode are formed of a same material.

6. The electroluminescent display device according to claim 1 , wherein the conductive layer includes a reflective material.

7. The electroluminescent display device according to claim 1 , wherein a height of the emission layer located at a center of the emission area is lower than a height of the emission layer at an edge of the emission area,
wherein the bank includes a first bank and a second bank disposed on the first bank, and
the first bank has a thickness smaller than the second bank and a width larger than the second bank.

8. The electroluminescent display device of claim 1 , wherein the bank is disposed at the active area and the dummy area, and a pattern of the conductive layer in the active area is different from a pattern of the conductive layer in the dummy area.

9. The electroluminescent display device according to claim 8 , wherein an overlapping area between the emission layer and the conductive layer in the dummy area is larger than an overlapping area between the emission layer and the conductive layer in the active area.

10. The electroluminescent display device according to claim 8 , wherein the pattern of the conductive layer in the dummy area is identical to the pattern of the second electrode in the dummy area.

11. The electroluminescent display device according to claim 8 , wherein the pattern of the conductive layer in the active area includes a first portion provided on the first portion of the second electrode.

12. The electroluminescent display device according to claim 11 , wherein the pattern of the conductive layer in the active area includes a second portion provided on the second portion of the second electrode.

13. The electroluminescent display device according to claim 8 , further comprising an auxiliary electrode electrically connected with the second electrode and provided below the bank,
wherein the auxiliary electrode is exposed through a contact hole in the bank, the second electrode includes a fourth portion extending to the auxiliary electrode along a lateral surface of the contact hole, and the pattern of the conductive layer in the active area includes a third portion provided on the fourth portion of the second electrode.

14. An electroluminescent display device including an active area and a dummy area surrounding the active area on a substrate, comprising:
a bank defining an emission area on the substrate;
an emission layer provided in the emission area defined by the bank;
a first electrode provided on the emission layer and the bank; and
a conductive layer provided on the first electrode,
wherein the first electrode includes a first portion having a first thickness, and a second portion having a second thickness, and the second thickness is greater than the first thickness,
wherein the emission layer has a height at the center of the emission area is lower than a height of the emission layer at an edge of the emission area, and
wherein the conductive layer is disposed only on the bank in the active area, and the conductive layer is disposed on the bank and the emission layer in the dummy area.

15. The electroluminescent display device according to claim 14 , wherein the conductive layer is in contact with the first portion of the first electrode.

16. The electroluminescent display device according to claim 14 , wherein the first portion of the first electrode is in direct contact with the bank.

17. The electroluminescent display device according to claim 14 , wherein the first electrode has a profile matching a profile of the emission layer in the emission area.

18. The electroluminescent display device according to claim 14 , wherein the conductive layer in the active area has a pattern different from that of the conductive layer in the dummy area.

19. The electroluminescent display device according to claim 14 , further comprising a circuit device layer including a thin film transistor, wherein the bank is disposed on the circuit device layer.

20. The electroluminescent display device according to claim 14 , further comprising an auxiliary electrode electrically connected with the first electrode and provided below the bank,
wherein the bank includes a contact hole for exposing the auxiliary electrode;
the first electrode includes a first portion provided on a lateral surface of the bank, a second portion provided on an upper surface of the bank, a third portion provided on an upper surface of the emission layer, and a fourth portion extending to the auxiliary electrode along a lateral surface of the contact hole, and
wherein the conductive layer is provided on the first portion, the second portion and the fourth portion of the first electrode.

21. The electroluminescent display device according to claim 14 , wherein the first portion of the first electrode has a surface inclined with respect to a horizontal surface.

22. The electroluminescent display device according to claim 14 , wherein the first portion of the electrode is provided on a lateral surface of the bank.

23. The electroluminescent display device according to claim 14 , further comprising a second electrode to form an electric field with the first electrode, so that the emission layer emits light.

Assignees

• Lg Display Co Ltd

Inventors

• Choi Jeongmook
• Jung Nackyoun
• Lee Sangbin

Classifications

• H10K59/80522

  combined with auxiliary electrodes · CPC title

• H10K59/80516 Primary

  combined with auxiliary electrodes, e.g. ITO layer combined with metal lines · CPC title

• H10K59/88

  Dummy elements, i.e. elements having non-functional features · CPC title

• H10K59/122

  Pixel-defining structures or layers, e.g. banks · CPC title

• H01L51/0005

  Electricity · mapped topic