Light-induced perturbation of the high-temperature equilibrium in phosphorus-dopeda-Si: H

We observed light-induced deviations from the high-temperature defect equilibrium in phosphorus-doped hydrogenated amorphous silicon ($a$-Si:H). These deviations rise and decay much slower than the dark equilibration times. The light-induced deviations from equilibrium result in an excess conductivity at high temperatures and a decrease photoconductivity of the rapidly quenched state at room temperature. We suggest that these phenomena result from a light-induced increase in the doping efficiency associated with an increase in dangling-bond defects according to the reaction ${\mathrm{P}}_{\mathrm{}\left(3\right)\mathrm{}}^0$+${\mathrm{Si}}_{\mathrm{}\left(4\right)\mathrm{}}^0$→${\mathrm{P}}_{\mathrm{}\left(4\right)\mathrm{}}^{+}$+${\mathrm{Si}}_{\mathrm{}\left(3\right)\mathrm{}}^{-}$.