Regrowth behaviour of Si1−xGex/Si structures formed by Ge+ ion implantation and post amorphisation

Abstract The synthesis of a buried layer of Si 1− x Ge x alloy by combining high dose Ge + implantation, amorphisation by high energy Si + implantation and low temperature solid phase epitaxial regrowth is reported. A Si/Si 1− x Ge x /Si heterostructure with graded interfaces and a maximum Ge concentration of 7.5 at.% has been successfully formed. The utility of amorphisation and low temperature solid phase growth across a graded phase boundary, as the last process step (EPIFAB) has been demonstrated. Examination of the sample by transmission electron microscopy has failed to resolve any crystallographic defects within the alloy layer, however, as expected, end-of-range defects are buried deep within the silicon substrate.