Light-induced creation of metastable defects in hydrogenated amorphous silicon carbide

We study the creation of metastable defects induced by illumination with la ser light (the Stabler-Wronski effect) in stoichiometric hydrogenated amorp hous silicon carbide (a-Si1-xCx : H). We follow the defect creation kinetic s through the decrease in photoluminescence as a function of time and incid ent power. A stretched-exponential increase in the number of defects is fou nd, in very much the same way as in hydrogenated amorphous silicon but with different material parameters. Comparison is made with the available model s. From the time t and power P dependences of the measured increase in the number of defect, we conclude that the well-known p(2/3)t(1/3) law does not hold for a-Si1-xCx : H. The details of the power dependence of the defect creation show that the mechanism of reconfiguration of defects is more appr opriate. Finally, it is shown that illumination with subbandgap light, norm alized to the same number of absorbed photons, produces only small changes. This phenomenon can be introduced into the models through a maximum config uration energy of a state that can be transformed into a non-radiative cent re.