Growth behaviour of ZnO thin films and nanowires on SrTiO 3 substrates

Abstract

We report on comparative investigations of ZnO thin films and nanowires grown on SrTiO 3 (STO) single crystal substrates. Using pulsed laser deposition technique, we could grow ZnO thin films with ( 11 2 ¯ 0 )- and (0001)-orientations on (100)- and (110)-orientated STO substrates, respectively. ZnO nanowires, grown by vapour condensation method with Au catalyst layers, did not show preferential alignment on either of the STO substrates. When the ZnO(0001)/STO(110) film was used as seed layer, we obtained dense and vertically aligned nanowires. Whereas, few and inclined nanowires were grown on the ZnO( 11 2 ¯ 0 )/STO(100) film. We discuss possible origins to cause all the observations.