(SSRL-M) A PHOTOEMISSION STUDY OF Au, Ge, AND Oz DEPOSITION Si(lll)

We have studied the interaction of a metal, Au, a semiconductor, Ge, and a non-metal, 02, with the NH4F etched Si(l 11) surface with photoemission spectroscopy. Two components were present in Si 2p core level spectra from the H-terminated surface. We observed the flat band condition from the as-etched, n-type, Si(l 11) surface. We performed stepwise depositions of Au and measured the band bending with photoemission spectroscopy. The Fermi level pinned near mid-gap as Au was deposited onto the as-etched surface, After the deposition of 1 ML of Au, a Au-silicide layer formed. This interracial component indicated that the passivating H layer was compromised. As the Au coverage was increased, layers of pure Au formed between the bulk silicon and the Au-silicide layer. The observed behavior was nearly identical to that of Au deposition on the Si(ll 1) 7x7 surface. Next, we tested the ability of the monohydride layer to sustain surfactant assisted growth of Ge. Ge islanding was observed at 400°C indicating that good surfactant growth was not obtained. This was consistent with the recent results of A. Sakai and T. Tatsumi, Appl. Phys. Lett. 61, 52 (1994) who report that the surface roughness was nearly the same with or without H at this temperature. Nthough the monohydride layer was not a good surfactant for th