Morphology tailored surface plasma emission of titanium capped ZnO films

Abstract Titanium (Ti)-capped ZnO samples with different roughness were prepared to investigate the effect of ZnO morphology on surface plasma energy of ZnO/Ti interface. ZnO nanoparticle samples with diverse particle shapes, sizes and filling factors were obtained by annealing at different temperatures. Ti-capped ZnO films annealed at 700 °C exhibit excellent photoluminescence property, which can attribute to the high degree of crystallinity (DC) and appropriate surface roughness. Tuning the microcrystalline structure and the ratio of inter-particle distance to the nanoparticle diameter of ZnO can facilitate the surface plasma resonance energy at ZnO/Ti interface close to the near-band-gap emission energy of ZnO, leading to an enhancement of the near-band-gap emission.