Epitaxial thin films of MgO an Si using metalorganic molecular beam epitaxy

Epitaxial cubic MgO thin films have been deposited on single crystal Si(001 ) substrates by metalorganic molecular beam epitaxy. The Mg source was the solid precursor magnesium acetylacetonate and a rf excited oxygen plasma wa s the oxidant. The growth process involved initial formation of an epitaxia l beta-SiC interlayer followed by direct deposition of a MgO overlayer. The films were characterized by in situ reflection high energy electron diffra ction, x-ray diffraction, conventional and high resolution transmission ele ctron microscopy, atomic force microscopy, Auger electron spectroscopy, and Fourier transform infrared spectroscopy. The beta-SiC interlayer had an ep itaxial relationship such that SiC(001)parallel to Si(001) and SiC [110]par allel to Si [110]. The SiC interlayer showed a columnar grain structure wit h planar defects including twin bands and stacking faults. The MgO overlaye r showed an epitaxial relationship given by MgO(001)parallel to Si(001) and MgO[110]parallel to Si[110]. No evidence of twins in the MgO layers was ob served. (C) 2000 American Vacuum Society. [S0734-211X(00)06104-7].