Epitaxial, electro‐optically active barium titanate thin films on silicon by chemical solution deposition

Recent progress in the integration of BaTiO 3 thin films with silicon has shown great promise for the development of on‐chip photonic devices. However, the highest performing thin films in the literature are deposited by costly and/or complex vacuum techniques. In this study, epitaxial BaTiO 3 thin films are deposited on thin SrTiO 3 template layers on Si(001) from an alkoxide‐based chemical solution under atmospheric conditions and yield an effective Pockels coefficient of 27 ± 4 pm/V for an ~85 nm film. Film crystallinity, microstructure, and defect nature are examined by X‐ray diffraction and high‐resolution transmission and scanning electron microscopy techniques and discussed within the context of the growth method as well as the observed electro‐optical response.