Photoluminescence yield and decay time of proton irradiated and thermally annealed a-Si0.35C0.65 : H alloys: A phenomenological model

We have studied the yield and the time evolution of pulsed laser induced ph otoluminescence in proton irradiated and thermally annealed amorphous hydro genated silicon carbon alloys prepared by plasma enhanced chemical vapor de position. Three major fluorescence decay channels have been observed with d ecay rates independent from proton irradiation and thermal annealing. Lack of correlation between yield and average decay time suggests a very simple phenomenological model which allows evaluation of the nonradiative time con stant which is found to be linearly correlated with the photoluminescence y ield. Our model suggests that radiative recombination occurs via exciton de cay while the nonradiative recombination is driven by the trapping of carri ers in defects states. (C) 2001 American Institute of Physics.