The effect of Mg dopant and oxygen partial pressure on microstructure and phase transformation of ZnTiO 3 thin films

Abstract

Mg-doped zinc titanate (ZnTiO 3) films were prepared using RF magnetron sputtering. Subsequent annealing of the as-deposited films was performed at a temperature ranging from 600 to 900 °C for 2 hours with a heating rate of 5 °C/min in air. It was found that the as-deposited films were amorphous and contained 2.77 at.% magnesium. This was further confirmed by the onset of crystallization that took place at annealing temperatures of 600 °C. The results showed that single Zn 2Ti 3O 8 phase was existed at 600 °C. When annealing is at 700 °C, the results revealed that mainly a hexagonal ZnTiO 3 phase accompanying a Zn 2Ti 3O 8 minor phase was observed. When annealing is at 900 °C, the results showed that single hexagonal ZnTiO 3 phase is stable at 900 °C. It means that ZnTiO 3 phase containing no Mg is unstable at 900 °C and is decomposed from hexagonal ZnTiO 3 to cubic Zn2TiO4 and rutile TiO 2 at 900 °C. In addition, the effect of oxygen partial pressure for the films deposited on the phase transformations and microstructures of zinc titanites thin film was investigated. © 2012 Lay Gaik Teoh et al.