title: Ultraviolet electroluminescence from ZnO/polymer heterojunction light-emitting diodes.
abstract: We report ultraviolet electroluminescence at 390 nm from diode structures consisting of electrodeposited ZnO nanorods sandwiched between a transparent SnO(2) film and a p-type conducting polymer. The nanorods are embedded in an insulating polystyrene layer. ZnO deposition occurs at 90 degrees C and produces vertically oriented nanorods with very high uniformity over areas of approximately 20 cm(2). Electron diffraction shows the nanorods to be single crystalline wurtzite ZnO. As-grown films show a broad electroluminescence band over the visible spectrum. Annealing at moderate temperatures (T = 300 degrees C) increases the emission and strongly raises the excitonic contribution. Optimally processed films show a narrow ultraviolet electroluminescence line at approximately 390 nm.
authors.affiliation: Physics Department, Portland State University, 1719 Southwest 10th Avenue, Portland, OR 97201, USA. rkoe@pdx.edu
authors.forename: R
authors.initials: R
authors.lastname: Könenkamp
authors.forename: R C
authors.initials: RC
authors.lastname: Word
authors.forename: M
authors.initials: M
authors.lastname: Godinez