A kinetic Monte–Carlo study of the effective diffusivity of the silicon self-interstitial in the presence of carbon and boron

The effect of carbon on self-interstitial diffusion in Si is studied by means of a kinetic Monte–Carlo simulation. It is found that modest levels of carbon (≳1017 cm−3) significantly reduce the effective interstitial diffusivity. From fitting self-interstitial profiles, migration energies and prefactors of the effective diffusivity have been determined for a variety of background carbon levels. In addition, we re-examine recent experiments performed in samples with significant levels of carbon, which attempt to measure the effective diffusivity by monitoring the spreading of boron marker layers. We show that the presence of boron in delta-doped markers significantly alters the measured self-interstitial diffusivity.