Light-emitting element, display module, lighting module, light-emitting device, display device, electronic device, and lighting device

Patent metadata

Field	Value
Publication number	US-9780338-B2
Application number	US-201615364746-A
Country	US
Kind code	B2
Filing date	Nov 30, 2016
Priority date	Aug 9, 2013
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A tandem light-emitting element in which generation of crosstalk can be suppressed even when the element is applied to a high-definition display is provided. In the tandem light-emitting element, a layer in contact the anode side of an intermediate layer contains 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen).

First claim

What is claimed is:

1. A light-emitting element comprising:
a first electrode;
an EL layer over the first electrode; and
a second electrode over the EL layer,
wherein the EL layer comprises a first light-emitting layer, a first layer, a first charge generation layer and a second light-emitting layer,
wherein the first charge generation layer comprises lithium,
wherein the first layer is provided between the first light-emitting layer and the first charge generation layer, and
wherein the first layer comprises a compound represented by the following Formula (iv):

2. The light-emitting element according to claim 1 , wherein the first charge generation layer comprises at least a charge generation region and an electron-injection buffer region.

3. The light-emitting element according to claim 2 , wherein an electron-relay region is provided between the charge generation region and the electron-injection buffer region.

4. The light-emitting element according to claim 2 , wherein the electron-injection buffer region comprises lithium.

5. The light-emitting element according to claim 2 ,
wherein the charge generation region comprises:
a layer comprising a substance having a hole-transport property; and
a layer comprising an acceptor substance.

6. The light-emitting element according to claim 1 ,
wherein the EL layer further comprises a second layer, a second charge generation layer and a third light-emitting layer, and
wherein the second charge generation layer comprises lithium,
wherein the second layer is provided between the second light-emitting layer and the second charge generation layer, and
wherein the second layer comprises the compound represented by the Formula (iv).

7. The light-emitting element according to claim 1 , wherein the EL layer further comprises a hole-injection layer, a hole-transport layer and an electron-transport layer comprising the first layer.

8. The light-emitting element according to claim 1 ,
wherein the EL layer further comprises a layer containing a condensed heteroaromatic compound,
wherein the layer containing a condensed heteroaromatic compound comprises iridium and a compound which comprises two nitrogen atoms in one condensed ring, and
wherein the layer containing a condensed heteroaromatic compound is in contact with the first layer.

9. The light-emitting element according to claim 8 , wherein the iridium is contained in part of the layer containing a condensed heteroaromatic compound and not contained in a region in contact with the first layer.

10. A light-emitting device comprising:
the light-emitting element according claim 1 ; and
a unit configured to control the light-emitting element.

11. A display device comprising:
the light-emitting device according to claim 10 ; and
a unit configured to control the light-emitting device.

12. A lighting device comprising:
the light-emitting element according to claim 1 in a lighting portion; and
a unit configured to control the light-emitting element.

13. A light-emitting element comprising:
a first electrode;
an EL layer over the first electrode, the EL layer comprising:
a first light-emitting layer over the first electrode;
a first layer over the first light-emitting layer;
a first charge generation layer over and in contact with the first layer; and
a second light-emitting layer over the first charge generation layer; and

a second electrode over the EL layer,
wherein the first charge generation layer comprises lithium, and
wherein the first layer comprises a compound represented by the following Formula (iv):

14. The light-emitting element according to claim 13 , wherein the first charge generation layer comprises at least a charge generation region and an electron-injection buffer region.

15. The light-emitting element according to claim 14 , wherein an electron-relay region is provided between the charge generation region and the electron-injection buffer region.

16. The light-emitting element according to claim 14 , wherein the electron-injection buffer region comprises lithium.

17. The light-emitting element according to claim 14 ,
wherein the charge generation region comprises:
a layer comprising a substance having a hole-transport property; and
a layer comprising an acceptor substance.

18. The light-emitting element according to claim 13 ,
wherein the EL layer further comprises:
a second layer over the second light-emitting layer;
a second charge generation layer over the second layer; and
a third light-emitting layer over the second charge generation layer, and

wherein the second charge generation layer comprises lithium, and
wherein the second layer comprises the compound represented by the Formula (iv).

19. The light-emitting element according to claim 13 ,
wherein the EL layer further comprises:
a hole-injection layer over the first electrode; and
a hole-transport layer between the hole-injection layer and the first light-emitting layer.

20. The light-emitting element according to claim 13 ,
wherein the EL layer further comprises a layer containing a condensed heteroaromatic compound,
wherein the layer containing a condensed heteroaromatic compound comprises iridium and a compound which comprises two nitrogen atoms in one condensed ring, and
wherein the layer containing a condensed heteroaromatic compound is in contact with the first layer.

21. The light-emitting element according to claim 14 , wherein the iridium is contained in part of the layer containing a condensed heteroaromatic compound and not contained in a region in contact with the first layer.

22. A light-emitting device comprising:
the light-emitting element according claim 13 ; and
a unit configured to control the light-emitting element.

23. A display device comprising:
the light-emitting device according to claim 22 ; and
a unit configured to control the light-emitting device.

24. A lighting device comprising:
the light-emitting element according to claim 13 in a lighting portion; and
a unit configured to control the light-emitting element.

Assignees

• Semiconductor Energy Lab

Inventors

• Suzuki Tsunenori
• Uesaka Shogo
• Yamaoka Ryohei
• Seo Satoshi

Classifications

• H01L27/322

  Electricity · mapped topic

• H01L51/5278 Primary

  Electricity · mapped topic

• H01L51/0052

  Electricity · mapped topic

• H01L27/3209

  Electricity · mapped topic

• H01L51/0085

  Electricity · mapped topic