Clear Experimental Proof of the Compliant Behavior of Free-Standing Si Nanostructures on SOI for Ge Nanoheteroepitaxy by GI-XRD

In summary, anomalous GI-XRD studies provide a clear proof that strain partitioning between pure Ge and pure Si nanostructures occurs. Si nanostructures on SOI can thus be applied as compliant substrate structures for Ge nanoheteroepitaxy. Further optimization is however required, as the compliance effect in the Si nanostructures can not alone account for the observed, almost full Ge nanostructure relaxation. Besides compliant substrate effects, SiGe interdiffusion and plastic relaxation by defect nucleation is observed. Lattice mismatched semiconductor integration on Si(001) is an intensively pursued R & D field to further develop main stream Si CMOS technologies. In “More Moore” research (focussing on aggressively scaled CMOS), InGaAs materials systems are for example studied as high mobility channel materials for future n-MOSFETs.