title: Defects in ZnO nanorods prepared by a hydrothermal method.
abstract: ZnO nanorod arrays were fabricated using a hydrothermal method. The nanorods were studied by scanning electron microscopy, photoluminescence (PL), time-resolved PL, X-ray photoelectron spectroscopy, and positron annihilation spectroscopy before and after annealing in different environments and at different temperatures. Annealing atmosphere and temperature had significant effects on the PL spectrum, while in all cases the positron diffusion length and PL decay times were increased. We found that, while the defect emission can be significantly reduced by annealing at 200 degrees C, the rods still have large defect concentrations as confirmed by their low positron diffusion length and short PL decay time constants.
authors.affiliation: Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong.
authors.forename: K H
authors.initials: KH
authors.lastname: Tam
authors.forename: C K
authors.initials: CK
authors.lastname: Cheung
authors.forename: Y H
authors.initials: YH
authors.lastname: Leung
authors.forename: A B
authors.initials: AB
authors.lastname: Djurisić
authors.forename: C C
authors.initials: CC
authors.lastname: Ling
authors.forename: C D
authors.initials: CD
authors.lastname: Beling
authors.forename: S
authors.initials: S
authors.lastname: Fung
authors.forename: W M
authors.initials: WM
authors.lastname: Kwok
authors.forename: W K
authors.initials: WK
authors.lastname: Chan
authors.forename: D L
authors.initials: DL
authors.lastname: Phillips
authors.forename: L
authors.initials: L
authors.lastname: Ding
authors.forename: W K
authors.initials: WK
authors.lastname: Ge