Electrical properties of the SrTiO3thin films prepared by radio frequency magnetron sputtering

Abstract

Strontium titanate thin films have been prepared on p-type Si(100) substrate by radio frequency(RF) magnetron sputtering. The films were deposited at 400 °C and annealed at various temperatures. The SrTiO₃ thin films were composed of three regions; an external surface layer, a main layer, and an interface layer. The silicon dioxide layers were present in the interface and were increased with increasing annealing temperature. The capacitance-voltage(C-V) characteristics showed a large negative shift and distorted shape for as-deposited film in argon discharge and were improved for SrTiO₃ film deposited using 30% oxygen content as a discharge gas. The C-V characteristics showed almost ideal shapes in the films annealed above 600 °C. The effective dielectric constant was maximum value in the films annealed at 600 °C and was increased with increasing the ratio of strontium and titanium.