Effects of hydrogen bond redistribution on photoluminescence of a-SiC:H films under thermal treatment

Abstract

Hydrogenated amorphous silicon carbide (a-SiC:H) films have been deposited using magnetron sputtering technique. An integrated investigation of the effect of vacuum annealing temperature on photoluminescence properties and paramagnetic defects and its correlation with structural transformation of a-SiC:H has been performed. Significantly enhanced light emission efficiency after low-temperature vacuum treatment (450°C) is found due to enhanced passivation of paramagnetic defects associated with carbon-rich chemically disordered structure. Subsequent high-temperature vacuum annealing results in a decrease of luminescent intensity that is associated with an increase of carbon-related paramagnetic defect states, shown to be the primary nonradiative recombination centers.