Dopant redistribution during oxidation of SiGe

This letter compares diffusion of boron in Si during oxidation both for pure Si and for Si covered with a very thin layer of SiGe alloy. It demonstrates that the thin layer of SiGe suppresses oxidation enhanced diffusion of boron. A mechanism is proposed based on suppression of Si interstitials. This phenomenon is then related to the faster rate of oxidation of bulk SiGe and SiGe-covered Si samples reported previously.