Electrical Characteristics of Strontium Titanate Films Prepared by Liquid Phase Deposition

Abstract

In this study, strontium titanate precursor was prepared by liquid phase deposition with aqueous solutions of ammonium hexafluoro-titanate, strontium nitrate and boric acid. Its polycrystalline structure shows high leakage current density and low dielectric constant. After thermal annealing in O2 ambient, the strontium titanate precursor is transformed gradually into strontium titanate film, as determined by X-ray diffraction (XRD). The leakage current and dielectric constant are improved. In order to further improve the leakage current, a thermal ultrathin SiO2 layer is added between strontium titanate and silicon. The leakage current density can be improved to 2.23×10-4 A/cm2 at 0.38 MV/cm and the dielectric constant is 39.