The infrared spectrum of oxygen in silicon.

Weak absorption bands appear at 1720, 1227 and 1013cm sup - 1 in the infrared spectrum of Czochralski silicon. A study of the stress induced dichroism of these features has been performed to confirm assignment of these bands to combination and overtone modes of interstitial oxygen vibrations. We show that the 1720 and 1227cm sup -1 bands involve the antisymmetric stretching mode of vibration which also give rise to the well known interstitial oxygen band at 1106cm sup -1 (the 9micron band). Our results are inconclusive for the 1013cm sup -1 line.