Dopant diffusion in strained and relaxed Si1-xGex

Preliminary studies were conducted on the effect of germanium content on antimony diffusion in silicon rich Si1-xCex strained layer heterostructures. The diffusion of Sb is characterised by a higher diffusivity in the alloy than in silicon from which we infer a higher vacancy mobility and/or vacancy concentration in Si1-xGex than in Si. We confirm that boron diffusion is dominated by an interstitial based mechanism in this composition range, and propose that Sb can be used as a monitor for vacancy diffusion in the alloy.