Crystal orientation of epitaxial oxide film on silicon substrate

Direct growth of oxide films on silicon is usually difficult because of extensive diffusion or chemical reaction between silicon (Si) and oxide materials. Schlom et. al. comprehensively investigate the thermodynamic stability of binary oxides. However the thermodynamic stability does not include factors for epitaxial growth such as lattice mismatch or crystallographic arrangement of oxide deposited on silicon surface. A magnesium oxide (MgO) was taken as an example of oxide materials and the absorption energy estimated on MgO placed on Si surface predicted the crystal orientation of epitaxial growth to be cubic on cubic [MgO(001) // Si(001) and MgO(100) // Si(100)]. These results agreed with experimental results observed on epitaxial MgO films deposited on Si surface. The evaluation of adsorption energy can be guideline for an epitaxial growth of oxide materials on silicon surface.