Structural and photoluminescence properties of silicon nanocrystals embedded in SiC matrix prepared by magnetron sputtering

Si nanocrystals (NCs) embedded in an SiC matrix were prepared by the deposition of Si-rich Si1-xCx/SiC nanomultilayer films using magnetron sputtering, subsequently followed by thermal annealing in the range of 800 similar to 1200 degrees C. As the annealing temperature increases to 1000 degrees C, Si NCs begin to form and SiC NCs also start to emerge at the annealing temperature of 1200 degrees C. With the increase of annealing temperature, two photoluminescence (PL) peaks have an obvious redshift. The intensity of the low-energy PL peak around 669 similar to 742 nm gradually lowers, however the intensity of high-energy PL peak around 601 similar to 632 nm enhances. The low-energy PL peak might attribute to dangling bonds in amorphous Si (a-Si) sublayers, and the redshift of this peak might be related to the passivation of Si dangling bonds. Whereas the origin of the high-energy PL peak may be the emergence of Si NCs, the redshift of this peak correlates with the change in the size of Si NCs. (C) 2010 Elsevier Ltd. All rights reserved.