No abstract

Quantitative data are presented on the infrared (IR) absorption of interstitial oxygen in oxygen-rich silicon using Fourier transform spectroscopy. Besides the well-known 515 and 1106 cm-' room temperature IR bands, due to the symmetric and antisymmetric vibrations of the Si20 entity, respectively, three other bands at 1227, 1720, and 1013 cm-' are reported, whose intensities are scaled with those of the 515 and 1106 cm-' bands. The band at 1227 cm -1 has often been confused with an oxygen precipitate band observed at 1225 cm-' in annealed silicon. Evidence is given that the 1227 cm -~ band is related to interstitial oxygen. It is also shown that another band at 1720 cm -1 is a combination of the antisymmetric mode of Si20 with a phonon combination of the silicon lattice. A weak band at 1013 cm-' is reported for the first time, and it is attributed to an overtone of the 515 cm-' mode.