A comprehensive model for the gettering of lifetime-killing impurities in silicon

A quantitative model for gettering processes is presented. First, lifetime- killing impurities that are fixed in the silicon lattice, either as precipi tates, trapped atoms, or substitutionals, must he extracted. Then they trav el as interstitials to a sink region where they cease to be harmful to the electron device behavior. The model is applied to several cases where alumi num or phosphorus gettering is performed. Agreement with experimental resul ts commonly observed is found, and several interesting conclusions are reac hed. Application to a more complex situation provides a way of identifying the phenomena involved and their importance. This quantitative model is tho ught to be a useful tool for the interpretation of gettering experiments. ( C) 2000 The Electrochemical Society.