Photoluminescence properties and random lasing behaviors of mist-CVD-grown ZnO disordered nanocrystals on c-plane sapphire substrate

We fabricated ZnO disordered nanocrystals on a c-plane sapphire substrate by mist chemical vapor deposition (mist-CVD). Grown ZnO disordered nanocrystals were two-dimensionally arrayed, and the height was determined to be less than approximately 200 nm based on scanning electron microscope observation. We investigated the photoluminescence properties of the grown ZnO disordered nanocrystals, and random lasing behaviors were considered to be observed owing to variable sharp peaks and spikes in photoluminescence spectra under high optically pumped conditions. Based on the results, the mist-CVD may be a useful crystal growth technique to fabricate optical microcavities based on ZnO disordered nanocrystals.