A LOW-ENERGY PHOTOLUMINESCENCE PEAK IN a-Si:H FILMS

A 0.65-0.70eV luminescence peak in a-Si:H films after illumination is reported. It is found that exposure to light decreases total integrated intensity of luminescence and also produces two luminescence peaks, one is in the range 0.80-0.90eV, and the other is in 0.65-0.70eV. The former disapears by annealing at 190°C, but the latter can not be removed. Similar luminescence peaks are observed in a-Si:H films prepared under higher RF power without illumination.