The Si-H stretching modes in proton-implanted crystalline material were studied. On the basis of the annealing behaviors and the dose dependences of the stretching-mode intensities, it was deduced that one complex gave rise to modes at 2121 and 2144/cm. A second complex gave rise to modes at 2166 and 2191/cm, and a third complex gave rise to a single mode at 2222/cm. The isotopic shifts of these centers were deduced from measurements of samples which had been implanted with protons and deuterons. The symmetries of the centers were deduced from uniaxial stress measurements. The 2121 and 2144/cm modes were attributed to VH2, the 2166 and 2191/cm modes were attributed to VH3, and the 2222/cm mode was attributed to VH4. Another mode, at 2068/cm, was tentatively attributed to VH. The Si-H and Si-D stretching modes of VHnDm (where n+m was less than 4) were calculated. These predictions closely fitted all of the experimentally measured frequencies.

B.B.Nielsen, L.Hoffmann, M.Budde: Materials Science and Engineering B, 1996, 36[1-3], 259-63