Epitaxial LaAlO3 thin film on silicon:: Structure and electronic properties

Epitaxial LaAlO3 films have been grown on Si (001) by molecular beam epitaxy with an ultrathin SrTiO3 seed layer. High resolution x-ray diffraction and transmission electron microscopy show the high quality epitaxial structure of LaAlO3 films, and the epitaxial relationship of LaAlO3 with Si is LaAlO3(001)parallel to Si(001) and LaAlO3[100]parallel to Si[110]. The band gap of epitaxial LaAlO3 films was measured to be 6.5 +/- 0.1 eV from O 1s loss spectra. Band offsets between crystalline LaAlO3 films and Si were determined to be partitioned equally with 2.86 +/- 0.05 eV for valence-band offset and 2.52 +/- 0.1 eV for conduction-band offset by using x-ray photoelectron spectroscopy. (C) 2007 American Institute of Physics.