Epitaxial PZT thin films on TiOx covered Pt/MgO substrate by RF magnetron sputtering

C-axis epitaxial ferroelectric Pb(Zr0.25Ti0.75)O-3 (PZT) thin films with high crystalline quality structure have been prepared at a temperature of 500 degreesC on MgO(200) single crystal covered with epitaxial Pt(200) thin film. PZT and Pt depositions were performed by RF magnetron sputtering and PZT growth was ensured provided that an ultra thin 0.3-3 nm TiOx upper layer was sputtered on Pt electrode prior to PZT deposition. Moreover it was found that in situ crystallization of a perovskite phase with epitaxial c-axis microstructure required to control precisely the O-2/(Ar+O-2) ratio in the plasma gas during both PZT and TiOx upper layer depositions. Otherwise, depositions led to crystallization of PZT with high c-axis orientation but simply textured microstructure. Growth of perovskite with either (101) or (111) preferred orientation has also been demonstrated at the same temperature. Additionally strong hysteresis loop deformations, likely rising from oxygen vacancies, are reported for the less oxidized samples.