Patent ID: 7521113

Claim:
A light emitting device, comprising: a) a substrate; b) a first electrically conductive layer forming an anode electrode layer on the substrate; c) a hole transport layer on said anode electrode layer; d) a layer of a light emissive material on said hole transport layer; e) an electron transport layer comprising fullerenes located on said layer of a light emissive material; f) a first interfacial layer located between said layer of light emissive material and said electron transport material, said first interfacial layer comprising organic molecules with a LUMO energy level of about 2 eV to about 3 eV and HOMO energy of about 5 eV to about 7eV located on said layer of light emissive material; g) a second electrically conductive layer forming a cathode electrode layer located on said electron transport layer; and h) a second interfacial layer located between said electron transport layer and said second electrically conductive layer, said interfacial layer comprising a fluoride compound for providing an Ohmic contact between said cathode electrode layer and said fullerene layer, wherein the organic molecules in said first interfacial layer are selected from the group consisting of 4,4 ′-bis(carbazol-9-yl) biphenyl; 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline; 1,3-Bis(5-(4-diphenylamino) phenyl-1,3,4-oxadiazol-2-yl)benzene; 3,4,5-Triphenyl-1,2,4-triazole; 3(Biphenyl-4-yl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole; 3,5-Bis (4-tert-butylphenyl)-4-phenyl-[1,2,4]triazole; 2-(4-Biphenylyl)- 5 -(4-tert-butylpheflyl)-1,3,4-oxadiazole; 1,3-Bis[5- (4-(1,1-dimethylethyl)phenyl)-1,3,4-oxadiazol-2-yl]benzene; 1,4-Bis(5-(4-diphenylamino)phenyl-1,3,4-oxadiazol-2-yl)benzene; and 1,3.5-Tris[5-(4-(1,1-dimethylethyl)phenyl)-1,3,4-oxadiazol-2-yl]benzene.