Efficiency of Intrinsic Gettering for Copper in Silicon

摘要

We studied intrinsic gettering (IG) efficiency of Cu in Czochralski-grown (CZ) silicon wafers subjected to two-step annealing in N_2 for 16 hr at 800℃ then for 0-16 hr at 1000℃. It is shown that the efficiency of IG depends on Cu contamination concentration. We estimated that the critical Cu contamination concentration for IG is about 1x10~(14) atoms/cm~2 on the surface. Moreover, we inferred from the dependence of gettering efficiency on oxygen-related defect density that the number of oxygen precipitates, rather than their size determines gettering efficiency. These results will help application of IG to device fabrication.