Thermal annealing of light−induced metastable defects in hydrogenated amorphous silicon nitride

Exposure to ultraviolet light induces paramagnetic, metastable defects in hydrogenated amorphous silicon nitride (a-SiN1.6:H) thin films. The thermally induced decay of the light-induced paramagnetic defects follows a stretched exponential dependence on annealing time, exp [−(t/τ)β], and displays a temperature-dependent β and τ. These results indicate that a multiple trapping or a trap-controlled hopping mechanism is involved in the annealing process with an apparent activation energy of 0.43 eV.