High electron mobility in strained Si channel of heterostructure with abrupt interface

Abstract

heterostructures with high electron mobility were grown by molecular beam epitaxy (MBE) combined with solid-phase epitaxy (SPE). The SPE growth completely suppressed Ge segregation in the layer on top of the Si channel layer. High-resolution cross-sectional transmission electron microscopy observation revealed that the heterointerfaces formed by the SPE growth technique were very flat compared with those for the MBE-grown samples. The electron mobility for an SPE-grown sample with a graded buffer layer was nearly one order of magnitude higher than without such a layer. A high electron mobility of was obtained at 15 K for the sample with a graded buffer layer ().