Epitaxy of Ni on Si(111) by Ion Beam Assisted Deposition

Abstract

AbstractEpitaxial growth of Ni (111) on Si (111) has previously been obtained at room temperature by 25-keV-Ni ion beam assisted deposition, where both ion and vapor fluxes were incident at 45° to the specimen normal. This work explores the effect of a wider range of deposition conditions on epitaxial film quality. Nominally 300-nm-thick films were deposited at room temperature on Si (111) and other substrates. The substrates were sputter cleaned by the Ni ion beam immediately prior to deposition. Ion energies of 25 to 175 keV, relative ion to vapor fluxes R from 0 to 0.1, and vapor deposition rates of 0.05 to 0.5 nm/s were examined. Bragg-Brentano symmetric x-ray diffraction evaluated film quality while Ni (220) grazing-incidence x-ray diffraction rocking curves verified film epitaxy. Film quality changed gradually over these deposition parameters, with an optimum at 25 keV and an R of about 0.01. At higher energies and R values sputtering and radiation damage destroyed the film epitaxy