Preparation and Properties of Thin Barium Titanate Films

Thin films of barium titanate were synthesized by the simultaneous deposition of the barium and titanium oxides evaporated by electron bombardment. The oxides were reacted on a substrate to form barium titanate during deposition. The reaction was carried out in an oxygen atmosphere at a substrate temperature in excess of 600°C. Experiments were performed to determine the range of conditions under which barium titanate was formed during deposition and to evaluate the potential of the films for electronic applications. The thickness of the films was in the range from 0.1 to Iμ. Effects of heat treatment on films deposited at room temperature are given. X‐ray spectroscopy and x‐ray diffraction were used to determine the composition and structure of the films. The maximum dielectric constant at room temperature is 1330, close to the value for polycrystalline barium titanate. Leakage current and frequency dependence of the dielectric properties are given. Films with high structural order show the characteristic phase transition, indicated by a peak in capacitance at 120°C.