Spectroscopic evidence for hydrogen-phosphorus pairing in zinc-doped InP containing hydrogen
A sharp IR line is observed in the low-temperature absorption spectrum of p-type InP doped with zinc when it has been passivated with hydrogen or deuterium. Because of the spectral characteristics of the line, it is attributed to the vibration of hydrogen or deuterium bonded to P atoms that are first neighbours of zinc acceptors. This consistently provides the same picture of the passivating complexes as in GaAs by replacing the As atom by the P atom. It is further argued that the microscopic structure of the acceptor complexes observed in germanium doped with zinc or beryllium when grown in a hydrogen atmosphere can be similarly explained by the formation of a Ge-H bond on the first neighbour of the Zn atom, leaving the acceptor atom tri-coordinated and neutralising one of the two holes. This explains the production of single acceptor complexes with trigonal symmetry whose electronic spectra have been analysed some time ago.