Epitaxial Si films on Ge(100) grown via H/Cl exchange

Thin Si films have been grown isothermally on Ge(100) substrates using alternating exposures of Si2H6 and Si2Cl6, maintaining chlorine and hydrogen surface termination. At 465 °C, film growth rate is roughly 2 monolayer per cycle (one cycle equals 1 Si2H6 and 1 Si2Cl6 exposure). At 475 °C a uniform epitaxial film is obtained, while islanding is observed at higher T. This process is thermally activated and is not strictly self-limiting, but has certain desirable characteristics of atomic layer epitaxy growth.