Hydrogen-interstitial Zn defect complexes and their effects on the device characteristics of heteroepitaxial p+n InP cell structures

Hydrogen passivation of Zn interstitial defects (Zn_I) is shown to enhance the turn-on voltage (V_TO) of heteroepitaxial p⁺n InP/GaAs cells. By using a combination of photoluminescence (PL), electrochemical C-V dopant profiling, secondary ion mass spectroscopy and current-voltage (I-V) measurements we demonstrate that the mechanism for this improvement results from reduction in recombination-generation and shunt losses due to hydrogen deactivation of Zn_I defect complexes whose high concentration is due to the presence of dislocations. The deactivation of Zn_I deep donors also results in an increase in the effective emitter acceptor concentration by ~50% due to the elimination of the compensation effect introduced by active Zn_I donors