Influence of growth temperature of TiO2 buffer on structure and PL properties of ZnO films

A series of ZnO films with TiO 2 buffer on Si (1 0 0) substrates were prepared by DC reactive sputtering. Growth temperature of TiO 2 buffer changed from 100 °C to 400 °C, and the influence on the crystal structures and optical properties of ZnO films have been investigated. The XRD results show that the ZnO films with TiO 2 buffer have a hexagonal wurtzite structure with random orientation, and with the increase of growth temperature of TiO 2 buffer, the residual stresses were released gradually. Specially, the UV emission enhanced distinctly and FWHMs (full width half maximum) decreased linearly with the increasing TiO 2 growth temperature. The results all come from the improvement of crystal quality of ZnO films.