FTIR was employed to study doped silicon passivated by atomic hydrogen, deuterium and implanted by proton. The localized vibrational modes of [BD] pairs, 1.560 cm-1 and 1263 cm-1, were excited with different passivation conditions of atomic deuterium. This shows that there are at least two possible positions for deuterium atoms around acceptor B. IR absorption spectra of doped silicon implanted by proton are different from that of undoped silicon, the hydrogen atoms prefer bonding around B acceptors. Only 1% implanted hydrogen atoms were turned into photoactive centers, most of implanted hydrogen atoms formed non-photoactive cen-ters, they might be hydrogen molecules, Hz.