Infrared stimulated photoconductivity overshoot in a-Si:H

At low temperatures, a subband-gap-light-excited photoconductivity overshoot Δσ was observed following a millisecond pulse of visible-light excitation in hydrogenated amorphous silicon. The relative change Δσ/σ was attributed to an increase in the optical absorption, Δα/α, due to deeply trapped carriers. Both the spectral distribution of Δα/α and its relaxation in the annealed state A are different from those in the light-soaked state B. Silicon dangling bonds generated by the Staebler–Wronski effect having different configuration than the thermally generated bonds are suggested as the explanation for the different behavior.