The phase change characteristics of Ge2Sb2Te5 (GST) films for phase change random access memory devices were improved by incorporating SiO2 into the GST film using cosputtering at room temperature. Isochronal annealing showed an increased resistivity of the crystallized GST films in proportion to the incorporated quantity of SiO2 which leads to a decrease in the writing current. SiO2 also inhibits crystallization of the amorphous GST film which can improve the long term stability of the metastable amorphous phase. (c) 2006 The Electrochemical Society.