We demonstrate efficient organic electroluminescent devices with multiple well structure and a p-doped hole injection and transport layer (HTL). The multiple well structure improves the efficiency and the controlled p-doped HTL leads to a lower operating voltage. An amorphous starbust [4,4′,4″-tris(N,N-diphenylamino)triphenylamine] doped with a strong organic acceptor, tetrafluoro-tetracyano-quinodimethane serves as the HTL material, a spiro-linked compound, 2,2′,7′,7′-tetra-kis-(diphenylamine)-9,9′-spirobifluoren e as an interlayer to provide a favorable interface and as a barrier within the multiple well structure and 8-tris-hydroxyquinoline as an emitter and well. The double-well device exhibits low operating voltage, less than 4 V, for obtaining 100 cd/m2 and the highest current efficiency exceeding 5 cd/A. Changes in the spectra due to the different well structures are also discussed.
|Number of pages||4|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Publication status||Published - 2001 Nov 1|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)