Interstitial oxygen determination in heavily doped silicon

Abstract

Systematic infrared transmission measurements have been performed on heavily Sb-doped (up to 2×1018 atoms/cm3) silicon samples. The interstitial oxygen content is obtained analyzing the optical response near the 1107-cm−1 oxygen absorption band with a new technique based on a curved baseline, accounting for free-carrier absorption. The results are discussed and compared with those obtained for the same samples by a short baseline technique and by secondary-ion mass spectroscopy (SIMS) analysis. Regression straight-line fits, relative to two lots of 16 samples each, show a good linear correlation between infrared (IR) and SIMS data, although the IR estimates are consistently lower than those obtained by SIMS.