The lifetimes of the Si-H vibrational stretch modes of the H2* (2062/cm) and HV·VH(110) (2072.5/cm) defects in crystalline Si were measured directly by transient bleaching spectroscopy from 10K to room temperature. The interstitial-type defect H2* has a lifetime of 4.2ps at 10K, whereas the lifetime of the vacancy-type complex HV·VH(110) was 2 orders of magnitude longer, 295ps. The temperature dependence of the lifetime of H2* was governed by TA phonons, while HV·VH(110) was governed by LA phonons. This behavior was attributed to the distinctly different local structure of these defects and the accompanying local vibrational modes.

Structure-Dependent Vibrational Lifetimes of Hydrogen in Silicon. G.Lüpke, X.Zhang, B.Sun, A.Fraser, N.H.Tolk, L.C.Feldman: Physical Review Letters, 2002, 88[13], 135501 (4pp)