Hydrogen passivation of grain boundaries in polycrystalline gallium arsenide

Exposure to a plasma of monatomic hydrogen at 300 °C for periods of 3–5 h is shown to significantly reduce the reverse leakage currents of surface barrier diodes fabricated from polycrystalline GaAs. The neutralization by hydrogen of electrical activity associated with grain boundaries leads to reductions in leakage current of a factor of 50 in material with grain sizes of 150–400 μm, and a factor of 3 in material with a typical grain size of ∼1 mm.