Effect of deposition parameters on the growth rate and dielectric properties of the Ba(SnxTi1−x)O3 thin films prepared by radio frequency magnetron sputtering

The growth rate and dielectric properties of the Ba(SnxTi1−x)O3 (BSxT1−x) thin films prepared by radio frequency (rf) magnetron sputtering at room temperature have been characterized as a function of deposition parameters. The BSxT1−x thin films are amorphous when deposited at low rf power (Rp = 100 and 125 W). The XRD result shows merely a single perovskite (BaTiO3) structure and the intensity of reflection peaks increases with the rf power increasing from 125 to 150 and 175 W. When the BSxT1−x thin film is deposited at Rp = 150 W and room temperature, the deposition rate decreases with the increasing working pressure (Wp) and O2/(O2 + Ar) ratio (Or). The refractive index of the BSxT1−x thin films is between 2.1 and 2.3, which shows that the variation of working pressure is not very significant. The dielectric constant of the BSxT1−x thin films increases with the Rp increasing from 100 to 150 W and decreases above 150 W. The leakage current density of the BS0.15T0.85 thin films nearly displays the ohmic behavior when the electric field is below 50 kV/cm. The conduction mechanism of the BS0.15T0.85 thin films involves the Schottky emission (SE) and Poole–Frenkel emission (PF) models. The BSxT1−x thin film shows a ferroelectric characteristic in the polarization-electric field plot.