High-frequency vibrational modes were observed at liquid-He temperatures in samples which had been grown in a H or D atmosphere. The highest-frequency ones were due to the overtones and combination modes of SiH fundamentals. Others were CH modes, due to (C,H) complexes, but the simultaneous presence of NH modes due to (N,H) complexes could not be ruled out. The results also seemed to indicate the existence of centers which included both SiH and CH or NH bonds. A sharp mode at 4349/cm was related to a weak SiH fundamental at 2210/cm. The related center was attributed to a vacancy which was fully decorated with H, with a nearest-neighbor C atom.

High-frequency hydrogen-related infrared modes in silicon B.Pajot, B.Clerjaud, Z.J.Xu: Physical Review B, 1999, 59[11], 7500-6