REACTIONS OF POINT-DEFECTS AND DOPANT ATOMS IN SILICON

We report long-range interstitial migration of B in Si at low temperature, initiated by kick-out reactions with self-interstitials (I) created by Si implantation. At 450-degrees-C, migration path lengths approximately 100 nm are measured within a time frame of 15 min. Observations of the number and spatial distribution of displaced B atoms in relation to the distributions of I and vacancies (V) computed from ion transport theory allow us to deduce the reaction kinetics. The reactions I+B(s) --> B(i), V+B(i) --> B(s), and I + V --> 0 are essentially diffusion limited, with capture radii of atomic dimensions.