Defect and Impurity-Complex Depassivation During Electron-Beam Irradiation of GaAs

Significant increases in thermal generation rates in molecular-beam epitaxy (MBE)-grown p-i-n-i-p GaAs structures are attributed to depassivation of hydrogen-defect/impurity complexes during high-intensity, low-energy electron-beam irradiation. Quantum calculations of relevant defect energy levels and reaction pathways suggest that depassivation of oxygen impurities is the likely cause of the observed degradation. Electric-field and excess-carrier-induced dehydrogenation of O
_As
-H complexes is identified as a likely rate-limiting process, leading to the observed enhanced thermal carrier generation in these structures.