c-axis oriented epitaxial films of the ferroelectric BaTiO 3 have been grown on (001) Si by reactive molecular-beam epitaxy. The orientation relationship between the film and substrate is (001) BaTiO 3 |(001) Si and  BaTiO 3∥ Si. The uniqueness of this integration is that the entire epitaxial BaTiO 3 film on (001) Si is c-axis oriented, unlike any reported so far in the literature. The thermal expansion incompatibility between BaTiO 3 and silicon is overcome by introducing a relaxed buffer layer of Ba xSr 1-xTiO 3 between the BaTiO 3 film and silicon substrate. The rocking curve widths of the BaTiO 3 films are as narrow as 0.4°. X-ray diffraction and second harmonic generation experiments reveal the out-of-plane c-axis orientation of the epitaxial BaTiO 3 film. Piezoresponse atomic force microscopy is used to write ferroelectric domains with a spatial resolution of ∼ 100 nm, corroborating the orientation of the ferroelectric film.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)