Low-temperature and high-rate deposition of SrTiO3 thin films by RF magnetron sputtering

SrTiO3 thin films have been prepared by RF magnetron sputtering at the a substrate temperature of 200 degrees C and a high deposition rate of 35 nm/min on Al/glass substrates. The deposition rate of the SrTiO3 thin film was controlled by RF power during the deposition. The orientation of the films changed and the grain boundaries became sparse with increasing RF power. Furthermore, the leakage current of the capacitors also increased with increasing RF power. As the RF power increased, the signal intensity ratios of O-2(+)/O and Ti/Sr in the optical emission spectroscopy decreased. The application of optimum working pressure resulted in recovery of the signal intensity ratios of O-2(+)/O in the optical emission spectroscopy and improvement in the properties of the SrTiO3 film deposited at a high RF power. The SrTiO3 film of 300 nm thickness exhibited a relative dielectric constant of 64 and a leakage current of 4 x 10(-10) A/cm(2) at the voltage of +3 V.