Thermal stability and oxygen-loss characteristics of Pt(O) films prepared by reactive sputtering

Pt(O) films having compositions ranging from pure Pt to amorphous platinum oxide a-PtOx (x ∼1.4) were prepared by reactive sputtering and examined during and after heating to temperatures used for deposition and processing of high-epsilon (HE) and ferroelectric (FE) materials (400-650°C). A two stage decomposition process was observed for a-PtOx (x∼1.4) films heated in N2, with the first stage of decomposition beginning at temperatures well below 400°C. In an O2 ambient, decomposition was accompanied by formation of a crystalline Pt3O4 phase prior to complete decomposition to metallic Pt. However, the relatively slow rate of oxygen loss from a-PtOx suggests that significant amounts of oxygen should remain in Pt(O) electrodes after HE/FE layer deposition. © 1999 American Institute of Physics.