DISSOCIATION-ENERGIES OF ACCEPTOR-HYDROGEN COMPLEXES IN INP

The dissociation energies of Zn-H, Cd-H, and Mg-H complexes in p-InP have been determined from the reactivation kinetics of these passivated dopants in reverse-biased Au Schottky diodes. The reactivation process is first order under these conditions, yielding thermal dissociation energies of 1.20 +/- 0. 10 eV for Zn acceptors, 1.40 +/- 0. 10 eV for Cd acceptors, and 1.35 +/- 0.10 eV for Mg acceptors. These results are consistent with the model in which the hydrogen passivates the acceptor by attaching to a neighboring P atom, leaving the acceptor essentially threefold coordinated. They also indicate that acceptor-hydrogen retrapping during cool down after epitaxial growth of p-InP layers is the primary cause of apparently stable acceptor passivation seen in such layers.