The behavior of B-H complexes, and the diffusion of H in B-doped material, were analyzed by using Raman scattering and infra-red reflection spectroscopy. It was found that, at temperatures below 200C, H diffusion was controlled by trapping at acceptor sites. This became negligible at higher temperatures. Changes in the zone-center optical phonon of Si, and in the vibrational local modes of B, occurred after H passivation. The H and B local modes were studied as a function of temperature and an external uniaxial stress. Analysis of H vibrational modes under stress revealed a non-trigonal symmetry of the B-H complexes at 100K, and a high mobility of H in these complexes. The results were found to be compatible with a bond-minimum site model for H at low temperatures. However, under stress and at high temperatures, off-bond H positions were suggested to exist. The stability of B-H complexes was also analyzed, and a dissociation energy of 0.6eV was deduced.

C.P.Herrero, M.Stutzmann, A.Breitschwerdt: Physical Review B, 1991, 43[2], 1555-75