Preparation of strontium titanate thin film on Si substrate by radio frequency magnetron sputtering

Abstract

Strontium titanate (SrTiO3) thin films on silicon wafers were grown by radio frequency (rf) magnetron sputtering at various growth conditions. The films were characterized using x-ray diffraction (XRD), infrared (IR) spectroscopy, and scanning electron microscopy (SEM). The films deposited below 200 °C were amorphous state and above 300 °C were crystalline state according to XRD and IR spectroscopy. The surface of strontium titanate film deposited at room temperature was smooth and those deposited at higher substrate temperatures showed discernible grains of which size were increased with increasing substrate temperature. By annealing at 600 °C in oxygen atmosphere, the amorphous strontium titanate were crystallized and the grain size of the films were increased. The deposition rate of the films were investigated by the growth parameters such as substrate temperature, Ar–O2 gas composition, and rf power.