Intermediate electrodes for stacked OLEDs

• US 7,728,517 B2
• Filed: 05/20/2005
• Issued: 06/01/2010
• Est. Priority Date: 05/20/2005
• Status: Expired due to Fees

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Stefanovic, Nemania, Aziz, Hany, Coggan, Jennifer A., Popovic, Zoran D.
• Primary Examiner(s): YAMNITZKY, MARIE ROSE
• Application Number:
  US11/133,978
• Publication Number:
  US 20060263629A1
• Time in Patent Office: 1,838 Days
• Field of Search: 428/690, 428/917, 427/58, 427/66, 313502-509, 257/40, 257 88-103, 257E51001-E51052, 25230116-30135
• US Class Current: 313/506
• 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
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

A stacked OLED includes a first electrode, a second electrode, a plurality of luminescent regions disposed between the first and second electrodes, and an intermediate electrode disposed between successive luminescent regions. At least one intermediate electrode comprise a metal-organic mixed layer disposed between a first charge injecting layer and a second charge injecting layer.

Claims

1. A stacked OLED comprising:

a first electrode;

a second electrode;

a plurality of luminescent regions disposed between the first and second electrodes; and

two or more intermediate electrodes, the intermediate electrodes being disposed between successive luminescent regions, wherein each intermediate electrode is a metal-organic mixed layer electrode comprising a first charge injecting layer, a second charge injecting layer, and a metal-organic mixed layer disposed between the first and second charge injecting layers, wherein the first and second charge injecting layers have different charge injecting functions and wherein the metal-organic mixed layer comprises a metal material comprising a metal selected from the group consisting of Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Sn, Pb, Bi, Se, Te, Nd, and combinations thereof.

2. The stacked OLED according to claim 1, wherein the first and second charge injecting layers of the metal-organic mixed layer electrode are selected from the group consisting of a hole injecting layer and an electron injecting layer.

3. The stacked OLED according to claim 1, wherein the metal-organic mixed layer of the metal-organic mixed layer electrode independently comprises a metal material in an amount of from about 5 to about 95 percent by volume and an organic material in an amount of from about 5 to about 95 percent by volume.

4. The stacked OLED according to claim 1, wherein the metal-organic mixed layer of the metal-organic mixed layer electrode comprises a metal material in an amount of from about 5 to about 30 percent by volume and an organic material in an amount of from about 95 to about 70 percent by volume.

5. The stacked OLED according to claim 1, wherein the first charge injecting layer is an electron injecting layer and the second charge injecting layer is a hole injecting layer.

6. The stacked OLED according to claim 1, wherein each intermediate electrode comprises a hole injecting layer comprising an electron-accepting material selected from the group consisting of FeCl3, AlCl3, InCl3, GaCl3, SbCl5, trinitrofluorenone, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, and combinations thereof.

7. The stacked OLED according to claim 6, wherein the hole injecting layer further comprises a hole transport material selected from the group consisting of N,N′

-di(naphthalene-1-yl)-N,N′

-diphenyl-benzidine (NPB), 4,4′

,4″

-tris(N,N-diphenylamino)triphenylamine (mTDATA), 2,5-di-tert-butylphenyl-N,N′

-diphenyl-N,N′

-bis(3-methylphenyl-(1,1′

-biphenyl)-4,4′

-diamine (BP-TPD), N,N′

-diphenyl-N,N′

-bis(3)methylphenyl-(1,1′

-biphenyl)-4,4′

-diamine (TPD), copper phthalocyanine (CuPc), vanadyl-phthalocyanine (VOPc), poly(3,4-ethylenedioxythiophene) (PEDOT), polyaniline (PAni), and combinations thereof.

8. The stacked OLED according to claim 1, wherein each intermediate electrode comprises an electron injecting layer comprising a material selected from the group consisting of Ca, Li, K, Na, Mg, Al, In, Y, Sr, Cs, Cr, Ba, Sc, Si and compounds thereof.

9. The stacked OLED according to claim 1, wherein the charge injecting layers independently have a thickness of from about 0.1 to about 50 nm.

10. The stacked OLED according to claim 1, wherein the metal-organic mixed layer of each of the intermediate electrodes independently has a thickness of from about 5 to about 100 nm.

11. The stacked OLED according to claim 1, wherein the two or more intermediate electrodes independently have a thickness of from about 5 to about 250 nm.

12. A display device comprising a stacked OLED according to claim 1.

13. A stacked OLED comprising:

an anode;

a cathode;

a plurality of luminescent regions disposed between the anode and the cathode; and

two or more intermediate electrodes, an intermediate electrode being disposed between successive luminescent regions, wherein each intermediate electrode independently comprises i) a hole injecting layer, ii) an electron injecting layer, and iii) a metal-organic mixed layer disposed between the hole injecting layer and the electron injecting layer, wherein the metal-organic mixed layer comprises a mixture of a metal and an organic material, the metal being selected from the group consisting of Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Sn, Pb, Bi, Se, Te, Nd, and combinations thereof.

14. The stacked OLED according to claim 13, wherein the hole injecting layer and the electron injecting layer each independently have a thickness of from about 0.1 to about 50 nm and the metal-organic mixed layer has a thickness of from about 5 to about 100 nm.

15. A display device comprising a stacked OLED according to claim 13.