Low temperature processing of SrBi2Ta2O9 thin films by low pressure and ozone annealing treatment

Abstract

We studied the two step annealing method by which SrBi2Ta2O9 (SBT) thin films were prepared at low temperature. As first step, the SET thin films deposited on Pt/Ti/SiO2/Si substrates using r.f. magnetron sputtering system were annealed at 650 degrees C in low pressure. By decreasing the annealing pressure, the degree of preferred orientation in the ferroelectric cannot only increased for the same processing condition but the grain size of SET films also increases. We investigated the ozone annealing treatment as a second step to improve the electrical properties. The property improvement by the ozone annealing is attributed to the reduction of oxygen defects in the SET film by reactive oxygen atom radicals Remanent polarization (P-r) and coercive field (E-c) were 2.1 mu C/cm(2), and 20.1 kV/cm, respectively.