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.