Microstructure evolution of highly Ga-doped ZnO nanocrystals

Ga-doped zinc oxide (ZnO) (ZnO:Ga) nanocrystals were synthesized by the vapor-solidification method to investigate morphological and structural evolution induced by Ga-incorporation. Ga-content was controlled in the full composition range (0–100%). As the Ga-content increased, the shape of nanocrystals changed from tetrapod- to rod-type. Hard X-ray photoemission spectroscopy (HXPES) measurement indicates that highly Ga-doped uniphase ZnO:Ga nanocrystals without a serious deterioration of morphology are achieved, which strongly suggests the feasibility of Ga as a successful n-type dopant for ZnO-based nanocrystals.