X-ray reflectometry on (SimGen)p short-period superlattices

Abstract

Grazing incidence x‐ray reflectometry on molecular beam epitaxygrown (Si m Ge n ) p short‐period superlattices is reported. Reflectivity curves are analyzed to estimate the structural perfection of samples grown on (100)Si and Ge substrates. Samples grown on Si with n<4 were found to have sharp interfaces (half a monolayer wide) but a structure with n≊8 had rough interfaces (two monolayers wide) consistent with a transition to a three‐dimensional growth mode. Superlatticesgrown on Ge, have sharper interfaces than equivalent (with Si and Ge layer thicknesses reversed) structures on Si.