Recombination center diffusion controlled by carbon concentration

摘要

A localised reduced lifetime region (1,25,41) is provided in a semiconductor device formed substantially of silicon. A predetermined concentration of carbon is provided in the region, and then the body is heated to incorporate a lifetime controlling impurity substantially within the carbon region. It is believed that the association between the impurity ions (M<+>) and the carbon atoms (C) on silicon lattice sites produces C-M<+> complexes with significant capture cross-sections. The carbon may be provided by addition during epitaxial growth of silicon material, during bulk growth of the silicon, or by implantation and/or diffusion.