Thermally Induced Defect Behavior and Effective Intrinsic Gettering Sink in Silicon Wafers

Abstract

Dislocation‐free Czochralski silicon wafers have been subjected to a two‐step annealing procedure to explore the intrinsic gettering (IG) phenomenon and the behavior of thermally induced microdefects using infrared absorption, preferential etching, and transmission electron microscopy (TEM). As a result, it is found that plastic lattice deformation introduced by dislocation and/or stacking faults is necessary for effective IG sinks. In spite of their extremely high density, microprecipitates with elastic strain but no plastic deformation do not result in effective IG. TEM observations clarify the change in density and/or structure of inner defects by precipitate dissolving after the second annealing at high temperature.