Degradation mechanism in carbon-doped GaAs minority-carrier injection devices

Hydrogen incorporated in GaAs-based minority-carrier injection devices can cause degradation, i.e., an increase in injection leakage current at low bias voltage. "Isolated" hydrogen donors (H/sup +/) induce rapid degradation, and even carbon-hydrogen complexes which are believed to be electrically neutral induce slow degradation. The decomposition of the carbon-hydrogen complexes is enhanced by minority-carrier injection producing electrically active isolated hydrogen donors (H/sup +/). The kinetics of the leakage current increase are well explained by the decomposition kinetics of the carbon-hydrogen complexes. Under minority-carrier injection, isolated hydrogen donors (H/sup +/) change to hydrogen acceptors (H/sup -/) by capturing two electrons. Hydrogen donors (H/sup +/) and hydrogen acceptors (H/sup -/) combine and become a molecular hydrogen which is thought to form {111} platelets. We infer that the degradation mechanism is closely related to the leakage through the {111} platelets.