Formation and stability of rocksalt ZnO nanocrystals in MgO

Abstract

Coimplantation of Zn and O ions into a single crystalline MgO and subsequent thermal annealing were applied in the synthesis of ZnO nanocrystals. Electron microscopy showed that rocksalt instead of wurtzite ZnO stabilizes for relatively large nanocrystals up to ∼15 nm, resulting from its small lattice mismatch with MgO of ∼1.7%. The vacancies initially created by implantation induce favorable nanocrystal growth kinetics and are effectively absorbed during the nucleation and growth processes. The optical band edge of the ZnO nanocrystals was detected at ∼2.8 eV. © 2007 American Institute of Physics.