Hydrogen coverage during Si growth from SiH₄ and Si ₂H₆

Time-of-flight direct recoiling (DR) measurements of surface hydrogen coverage (θH) are made in situ during chemical beam epitaxy growth of Si from Si2H6 on Si(100) as a function of temperature and disilane flux. Temperatures (T) of 300-900°C and fluxes from 1015 to 1017 molecules cm-2 s-1 are used. Limited data for SiH4 are also presented. Predictions of θH from a steady state kinetic model are compared with the measurements, enabling the reactive sticking probability (S) of Si 2H6 to be estimated at T≳500°C.