Structural and electrical characterization of annealed Si1-xCx/SiC thin film prepared by magnetron sputtering

Si-rich Si1-xCx/SiC multilayer thin films are prepared using magnetron sputtering, subsequently followed by thermal annealing in the range of 800–1200?C. The influences of annealing temperature(Ta) on the formation of Si and/or SiC nanocrystals(NCs) and on the electrical characteristics of the multilayer film are investigated by using a variety of analytical techniques, including X-ray diffraction(XRD), Raman spectroscopy and Fourier transform infrared spectrometry(FT-IR),current–voltage(I–V) technique, and capacitance-voltage(C–V) technique. XRD and Raman analyses indicate that Si NCs begin to form in samples for Ta ≥ 800?C. At annealing temperatures of 1000?C or higher, the formation of Si NCs is accompanied by the formation of SiC NCs. With the increase in the annealing temperature, the shift of FT-IR Si–C bond absorption spectra toward a higher wave number along with the change of band shape can be explained by a Si–C transitional phase between the loss of substitutional carbon and the formation of SiC precipitates and a precursor for the growth of SiC crystalline. The C–V and I–V results indicate that the interface quality of Si1-xCx/SiC multilayer film is improved significantly and the leakage current is reduced rapidly for Ta ≥ 1000?C, which can be ascribed to the formation of Si and SiC NCs.