The phase transition of Bi-Pt alloys at the interface of Pt/SrBi2Ta2O9 and its effect on interface roughness

Abstract

Pt/SrBi2Ta2O9(SBT)/CeO2/Si (MFIS) structures were investigated for observing the change of electrical properties and morphology of interface of Pt/SBT after post-annealing of Pt top electrodes. The morphology of Pt/SBT interface became smooth and Bi oxide was formed at the bottom of Pt top electrode after post-annealing Pt top electrode. In order to describe the origin of these changes, Bi-oxide/Pt/SiO2/Si structure was investigated with annealing temperatures about the reaction between Ei oxide and Pt. We can describe that the smooth interface of Pt/SBT and the consumption of metallic Bi, which the reason why electrical properties were drastically improved, is induced by the melting of Pt-Bi alloys and formation of Bi-oxide after post-annealing Pt top electrode.