Crystallographic characterization of GexSi1−x/Si superlattices grown by remote plasma‐enhanced chemical vapor deposition

Single‐crystal GexSi1−x/Si superlattices have been successfully fabricated using remote plasma‐enhanced chemical vapor deposition, a novel low‐temperature thin‐film growth technique. Reflection high‐energy electron diffraction, cross‐sectional transmission electron microscopy (XTEM), plan view TEM, x‐ray‐diffraction, and secondary‐ion mass spectroscopy techniques have been applied to study the crystallographic properties of the superlattice structures. Arrays of dislocation lines, which are either parallel or perpendicular to each other, have been observed in the superlattices for those cases in which the total layer thickness exceeds the critical layer thickness. The location, orientation, and Burgers vectors of the misfit dislocation lines have been analyzed. Possible mechanisms of the generation of the misfit dislocations are also discussed.