White organic light emitting device

• US 20080297036A1
• Filed: 03/03/2008
• Published: 12/04/2008
• Est. Priority Date: 05/31/2007
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Mobile Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Kim, Yu-jin, Noh, Tae-yong, Choi, Byoung-ki, Tamura, Shinichiro, Kim, Myeong-suk, Han, Eun-sil
• Granted Patent: US 7,859,186 B2
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/19 Tandem OLEDs
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths

Abstract

A white organic light emitting device includes an anode, a cathode, a charge generation layer arranged between the anode and the cathode and an organic layer arrangement arranged between the anode and the cathode, the organic layer arrangement including a green light emitting layer, a blue light emitting layer, and a red light emitting layer, one of the green light emitting layer, the blue light emitting layer, and the red light emitting layer includes a first light emitting layer and second light emitting layer, the charge generation layer being arranged between the first light emitting layer and the second light emitting layer.

Claims

1. A white organic light emitting device, comprising:

an anode;

a cathode;

a charge generation layer arranged between the anode and the cathode; and

an organic layer arrangement arranged between the anode and the cathode, the organic layer arrangement including a green light emitting layer, a blue light emitting layer, and a red light emitting layer, one of the green light emitting layer, the blue light emitting layer, and the red light emitting layer includes a first light emitting layer and second light emitting layer, the charge generation layer being arranged between the first light emitting layer and the second light emitting layer.

2. The white organic light emitting device of claim 1, wherein other ones of the green light emitting layer, the blue light emitting layer, and the red light emitting layer includes single light emitting layers, and wherein the single light emitting layers are separated by the charge generation layer.

3. The white organic light emitting device of claim 1, wherein other ones of the green light emitting layer, the blue light emitting layer, and the red light emitting layer includes single light emitting layers, and wherein a sum of currents applied to the first and second light emitting layers is greater than a current applied to each of the single light emitting layers upon application of current to the organic layer arrangement upon application of a voltage between the anode and the cathode.

4. The white organic light emitting device of claim 1, further comprising a first electron transport layer arranged between a layer of said organic layer arrangement and the charge generation layer, the first electron transport layer also being arranged between the anode and the charge generation layer.

5. The white organic light emitting device of claim 4, further comprising an electron injection layer arranged between the charge generation layer and the first electron transport layer.

6. The white organic light emitting device of claim 1, further comprising a hole transport layer arranged between a layer of said organic layer arrangement and the charge generation layer, the hole transport layer also being arranged between the cathode and the charge generation layer.

7. The white organic light emitting device of claim 6, further comprising a hole injection layer arranged between the hole transport layer and the charge generation layer.

8. The white organic light emitting device of claim 1, wherein the charge generation layer comprises at least one material selected from a group consisting of an organic compound of aryl amine group, a metal, a metal quinolate, a metal oxide, a metal carbonate, and a metal fluoride.

9. The white organic light emitting device of claim 1, wherein the charge generation layer comprises at least one layer.

10. The white organic light emitting device of claim 8, wherein the organic compound of the aryl amine group is an element selected from a group consisting of α

-NPD, BCP, 2-TNATA, TDATA, m-MTDATA, spiro-TAD, and sprio-NPB.

11. The white organic light emitting device of claim 8, wherein the metal is an element selected from a group consisting of Cs, Mo, V, Ti, W, Ba, and Li.

12. The white organic light emitting device of claim 8, wherein the metal quinolate comprises lithium quinolate (Liq).

13. The white organic light emitting device of claim 8, wherein the metal oxide is an element selected from a group consisting of Re₂O₇, MoO₃, V₂O₅, WO₃, TiO₂, and Cs₂CO₃.

14. The white organic light emitting device of claim 8, wherein the metal carbonate comprises Cs₂CO₃.

15. The white organic light emitting device of claim 8, wherein the metal fluoride is an element selected from a group consisting of BaF, LiF, and CsF.

16. The white organic light emitting device of claim 1, further comprising a hole transport layer arranged between the anode and the organic layer arrangement.

17. The white organic light emitting device of claim 16, further comprising a hole injection layer arranged between the anode and the hole transport layer.

18. The white organic light emitting device of claim 1, further comprising an electron transport layer arranged between the cathode and the organic layer arrangement.

19. The white organic light emitting device of claim 18, further comprising an electron injection layer arranged between the cathode and the electron transport layer.

20. The white organic light emitting device of claim 1, wherein each of the green light emitting layer, the blue light emitting layer, and the red light emitting layer comprises a host and a dopant selected from a group consisting of a fluorescent dopant and a phosphorescent dopant.

21. The white organic light emitting device of claim 20, wherein the green light emitting layer comprises Alq₃ as the host and Coumarin6 as a dopant.

22. The white organic light emitting device of claim 20, wherein the blue light emitting layer comprises TBADN as the host and DPAVBi as the dopant.

23. The white organic light emitting device of claim 20, wherein the red light emitting layer comprises Alq₃ as the host and DCJTB as the dopant.

24. The white organic light emitting device of claim 1, wherein the green light emitting layer, the blue light emitting layer, and the red light emitting layer are sequentially arranged on the anode.

25. The white organic light emitting device of claim 24, said one of the green light emitting layer, the blue light emitting layer, and the red light emitting layer is the blue light emitting layer.