Published online by Cambridge University Press: 10 February 2011
The effect of growth conditions such as substrate temperature and oxygen partial pressure on the microstructure and properties of pulsed laser deposited SBTN thin films on Si(100) and MgO(100) substrates have been studied. Crystallization of films begins at room temperature but, the obtained phase was non-ferroelectric. The influence of oxygen pressure (150 to 450 mTorr) on crystallinity of the films deposited on Si(100) at 750°C is negligible. XPS studies of as-deposited films reveal that the oxygen vacancies are preferably present near the Bi ions at the Bi2O2 layers and vary with substrate temperature and oxygen partial pressure. Also, XPS studies of Sr 3d core level for SBTN films suggest that the oxygen ions in the Sr(Ta/Nb)2O7 perovskite layers are much more stable than those in the Bi2O2 layers. Micro-Raman studies of SBTN films deposited below 700°C show Raman modes of a non -ferroelectric phase.