Reversible structural changes in dischargehyphen;produced amorphous silicon

摘要

This work studies the reversible, structural changes of undoped hydrogenated amorphous silicon films under prolonged illumination and thermal annealing. Experimental results from infrared spectroscopy showed that the strength of the stretch modes of SiH and SiH2decrease more slowly in the initial stage and then more rapidly at about 1018cmminus;3spin density during prolonged illumination periods. On the other hand, the strength can be restored to its original value after a certain period of thermal annealing at 250thinsp;deg;C. These results are correlated with those obtained from electron paramagnetic resonance and photoconductivity measurements, in which the rate equations were analyzed to reveal the origin of recombinations responsible for the weak Sindash;Si bond breaking. An explanation is proposed in this study to illustrate the lighthyphen;induced bond breaking and its repair.