18Â MeV electron irradiation-induced metastability in hydrogenated amorphous silicon

Effect of high energy electron irradiation on hydrogenated amorphous silicon (a-Si:H) has been studied. The electron beam with an energy of 18 MeV and fluence in the range of 1014-1015 cm−2 has been used. The degree of degradation and recovery of the material has been estimated using photoconductivity measurements. A saturation of the irradiation-induced degradation has been observed at a level typical for light-induced degradation. Thermal annealing of the irradiated a-Si:H films has been carried out in the temperature range of 120-180 °C. The time dependence of annealing obeys a stretched-exponential law. A fast and complete annealing occurs at the temperature of 180 °C. It has been suggested that 18 MeV electron beam-induced metastability can be accounted for by using hydrogen-related models for light-induced degradation.