Elaboration of Graded Band-Gap a-SiC Thin-Film Using RF Magnetron Sputtering Technique

In this paper, Graded Band-Gap (GBG) amorphous-silicon Carbide (a-SiC) thin-film was successfully fabricated using RF magnetron technique on glass substrate. Accordingly, a-SiC ultrathin layers were sputtered at dissimilar RF power values. XRD and Spectrophotometry measurements were performed to assess the structural, optical and electronic properties of the prepared a-SiC samples. It was found that all samples exhibit an amorphous state. Besides, characterizations showed that the a-SiC band gap can be tuned by using dissimilar RF power values during the sputtering process. In this context, GBG a-SiC film is elaborated by a sequential sputtering process at various RF power values ranging from 60 W to 120 W. It was revealed that the optical band gap is reduced from 2.54 eV to 1.9 eV for the RF power values of 60 W and 120 W, respectively. This is mainly attributed to the effect of the Si and C content on the electronic behavior of the SiC alloy, where the variation of the RF power can induce significant changes regarding the Si/C ratio of the SiC sample. These significant results suggest the elaboration of GBG a-SiC, which can be highly suitable for various applications including photovoltaic and optoelectronic devices.