Crystalline correlation of epitaxial Si films with underlying spinel films in Si/(MgO Al2O3) spinel/Si structure

Abstract
Using epitaxial magnesia spinel (MgO Al2O3) films on (100) Si, heteroepitaxial Si films (0.6–3 μm) on these substrates are obtained by a conventional chemical vapor deposition method. The crystallinity of both epitaxial Si and spinel films was investigated by x‐ray diffraction techniques. Silicon film quality becomes more perfect on thinner spinel films with smoother surfaces in the range of more than ∼0.1 μm, in spite of the spinel crystal perfection becoming inferior with decreasing film thickness. These results are discussed in terms of the spinel surface roughness effect on Si nuclei coalescence.