| 摘要 |
PROBLEM TO BE SOLVED: To provide an electron injection electrode with high efficiency by selecting a fluoride layer so that two layers are operated as an electron injection contact and two layers provide stability to air corrosion. SOLUTION: An EL device 10 has a substrate 11, a hole injection electrode 13, an organic EL layer 15, and an electron injection electrode 17 in order. The electron injection electrode 17 contains a fluoride layer 17a and a conductive overlay layer 17b. The substrate 11 is a glass substrate. When the electrode 13 is biassed in positive, the electrode 13 injects holes in the organic EL layer 15. The electrode 13 is an optically transparent conducting oxide layer or a thin metal layer in order that light is allowed to cross the organic EL layer 15 and the substrate 11. The organic EL layer 15 has a monolayer operating as a light emitting unit or a multilayer containing a light emitting layer and a carrier confining layer. When the electron injecting electrode 17 is biassed in negative, the electrode 17 injects electrons in the organic EL layer 15. The electron injection electrode 17 contains a thin layer 17a and a thick layer 17b. The fluoride is selected from alkali fluorides and alkali earth fluorides. |
