Growth and characterization of highly c-axis textured SrTiO3 thin films directly grown on Si(001) substrates by ion beam sputter deposition

Highly c-axis textured SrTiO3 (STO) thin films have been directly grown on Si(001) substrates using ion beam sputter deposition technique without any buffer layer. The substrate temperature was varied, while other parameters were fixed in order to study effect of substrate temperature on morphology and texture evolution of STO films. X-ray diffraction, pole figure analysis, atomic force microscope, and high-resolution electron microscopy were used to characterize and confirm quality and texture of the STO films. The experimental results show that optimum substrate temperature to achieve highly c-axis textured films is at 700 degrees C. The full width at half maximum (FWHM) of 002STO was found to be 2 degrees and fraction of (011) orientation was as low as 1%. The surface morphology was Volmer-Weber growth mode with a small roughness similar to 1 nm. The lowest leakage current density (5.8 mu A/cm2 at 2 V) and the highest dielectric constant (eSTO similar to 98) were found for highly c-axis textured films grown at 700 degrees C. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)