US RE42,561 E1
Phosphorescent organic light emitting devices
Chihaya Adachi, Fukuoka (Japan); Marc A. Baldo, Cambridge, Mass. (US); and Stephen R. Forrest, Ann Arbor, Mich. (US)
Assigned to The University of Southern California, Los Angeles, Calif. (US); and The Trustees of Princeton University, Princeton, N.J. (US)
Filed on Apr. 16, 2007, as Appl. No. 11/787,753.
Application 11/787753 is a reissue of application No. 09/629335, filed on Aug. 01, 2000, now 6,645,645, filed on Nov. 11, 2003.
Claims priority of provisional application 60/207330, filed on May 30, 2000.
This patent is subject to a terminal disclaimer.
Int. Cl. H05B 33/14 (2006.01); H01L 51/54 (2006.01)
U.S. Cl. 428—690  [428/917; 313/504; 313/506; 257/102; 257/103; 257/E51.044] 26 Claims
 
1. An organic light emitting device comprising an anode, a cathode and an emissive layer, wherein the emissive layer is located between the anode and the cathode and the emissive layer comprises an electron transporting host material doped with a phosphorescent dopant material,
[ wherein the phosphorescent dopant material is an organometallic complex having the formula selected from L3M and L2MX, wherein
M is a third row transition metal;
L is a monoanionic bidentate ligand that is coordinated to M with an sp2 hybridized carbon and a heteroatom of the ligand L; and
X is a monoanionic bidentate ligand;]
[ and ] wherein the phosphorescent dopant material has a HOMO energy less than the ionization potential of the electron transporting host material [ and a LUMO energy level lower than a LUMO energy level of the electron transporting host material.]