An apparatus for supersonic jet epitaxy of thin films

An ultrahigh vacuum chemical beam epitaxy growth system has been built usin g multiple supersonic jets as precursors. Supersonic jets provide very high flux to the growth front while maintaining low growth pressures (10(-5) To rr). Activation barriers to chemisorption are overcome by using hypertherma l (1-10 eV) precursors for heteroepitaxial growth. Improvement in growth ra tes and higher degrees of structural orientation are obtained at lower temp eratures. Wide band gap semiconductors (SiC, GaN, and AlN) are deposited on silicon substrates using neutral chemical precursors. Epitaxial growth of SiC on silicon has been obtained at the lowest temperatures reported to dat e using a supersonic jet of methylsilane. (C) 2000 American Institute of Ph ysics. [S0034-6748(00)03903-4].