Influence of 250Â keV Ge ions fluence on electrical and optical properties of SiC

Commercially graded SiC samples were implanted with 250 keV germanium ions (Ge+) at room temperature. For Ge+ ions source, laser-induced plasma (LIP) technique was used. Ge+ implantation was confirmed by energy dispersive X-ray (EDX) analysis. Change in FWHM and lattice constant of SiC samples has been observed after the Ge implantation, calculated by Bragg's law from XRD analysis. A comparison of the electrical and optical properties of SiC before and after Ge+ implantation (SiC:Ge) has also been made. Electrical diagnostic comprises of a four-probe method for the measurement of resistivity whereas Raman spectroscopy is employed for the optical investigation. Resistivity measurements of SiC and SiC:Ge samples showed that resistivity decreases as Ge+ implantation increases. Raman spectroscopy of the SiC and SiC:Ge showed that Raman band became broadened and is shifted towards the lower wave number with the increase in Ge ion fluence. The increase in Ge ions fluence enhances the lattice defects which are responsible for broadening in XRD and Raman peaks as well as increase in conductivity of the samples.