title: Luminance mechanisms in green organic light-emitting devices fabricated utilizing tris(8-hydroxyquinoline)aluminum/4,7-diphenyl-1, 10-phenanthroline multiple heterostructures acting as an electron transport layer.
abstract: The electrical and the optical properties in green organic light-emitting devices (OLEDs) fabricated utilizing tris(8-hydroxyquinoline)aluminum (Alq3)/4,7-diphenyl-1,10-phenanthroline (BPhen) multiple heterostructures acting as an electron transport layer (ETL) were investigated. The operating voltage of the OLEDs with a multiple heterostructure ETL increased with increasing the number of the Alq3/BPhen heterostructures because more electrons were accumulated at the Alq3/BPhen heterointerfaces. The number of the leakage holes existing in the multiple heterostructure ETL of the OLEDs at a low voltage range slightly increased due to an increase of the internal electric field generated from the accumulated electrons at the Alq3/BPhen heterointerface. The luminance efficiency of the OLEDs with a multiple heterostructure ETL at a high voltage range became stabilized because the increase of the number of the heterointerface decreased the quantity of electrons accumulated at each heterointerface.
authors.affiliation: Research Institute of Information Display, Department of Electronics and Computer Engineering, Hanyang University, Seoul 133-791, Korea.
authors.forename: Dong Chul
authors.initials: DC
authors.lastname: Choo
authors.forename: Su Yul
authors.initials: SY
authors.lastname: Seo
authors.forename: Tae Whan
authors.initials: TW
authors.lastname: Kim
authors.forename: You Young
authors.initials: YY
authors.lastname: Jin
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Seo
authors.forename: Young Kwan
authors.initials: YK
authors.lastname: Kim