Interface structure and phase of epitaxial SrTiO3 (110) thin films grown directly on silicon

The interface structure and phase between SrTiO3 (110) on Si (100) have been investigated using high-resolution transmission electron microscopy and x-ray photoelectron spectroscopy. The SrTiO3∕Si interface was found to be epitaxially crystallized without any amorphous oxide layer. The formation of Sr silicate at the interface was suggested by considering the fact of the core-level spectra of the Si 2p, O 1s, and Sr 3d. Our results suggest that the presence of a coincident site lattice at the interface between Si and a Sr silicate and/or SrTiO3 may help to stabilize SrTiO3 in the epitaxial orientation reported in the work.