Growth Temperature Dependence of SrTiO 3 Thin Films by Molecular Beam Epitaxy

The effect of Sr deposition on the chemically formed SiO 2 layer of Si(001) substrates and consequently the growth of SrTiO 3 thin films on the Si(001)-Sr(2×1) surface have been studied using reflection high-energy electron diffraction (RHEED), X-ray diffraction and atomic force microscopy. After Sr deposition on the chemically formed SiO 2 /Si surface, a stable and well ordered Si(001)-Sr(2×1) surface is formed. The SrTiO 3 film grown on the reconstructed Si(001)-Sr(2×1) surface at 350°C is amorphous. The sharp, streaky RHEED patterns and the strong STO (002) diffraction peaks and the smooth surface with root mean square roughness of approximately 4 Å suggest that high-quality SrTiO 3 films are fabricated at temperatures (400–500°C) using molecular oxygen in molecular beam epitaxy.