Effect of germanium on redistribution of boron and phosphorus during thermal oxidation of silicon

The diffusion-segregation redistribution of B and P impurities during thermal oxidation of Ge-containing Si has been simulated. In all probability, Ge affects the diffusion of B and P via bulk recombination of self-interstitials (SI) on Ge centres, rather than through a decrease in the rate of surface generation of SI in thermal oxidation. The Ge-induced retardation of the oxidation-enhanced diffusion of B and P in Si and redistribution of the B and P impurities at the SiO2/Si interface are described. The parameters of SI bulk recombination on Ge-related centres are found and an increase in the segregation coefficient of B in the SiO2-Si system in the presence of Ge is revealed by comparing the calculated and experimental concentration distributions.