Initial study on the structure and photoluminescence properties of SiC films doped with Co

Silicon carbide (SiC) films doped with Cobalt (Co) were prepared by the RF-magnetron sputtering technique on p-Si substrates with a composite target of a single-crystalline SiC containing several Co pieces on the surface. The as-deposited films were annealed in the temperature range of 600-1000 °C under nitrogen ambient. The structure of the samples has been characterized by X-ray diffraction, atomic force microscope, and X-ray photoelectron spectroscopy. The results showed that with an increase of the annealing temperature, the SiC crystal is formed and that majority of Co atoms in the SiC have formed the Co-Si compounds such as CoSi and CoSi2 phases, resulting in the formation of the C clusters. Then the photoluminescence (PL) spectra of the samples were observed in the visible range at room temperature. The 370-nm PL band is related to the luminescence centres formed by the Si-O related defects in the samples. The origin of the 413-nm PL band is associated with the emission luminescence from 6H-SiC, which has a great relation to the SiC quality.