Auger and energy loss spectroscopy analysis of silicon carbide (SiC) surfaces

Auger electron spectroscopy and electron loss spectroscopy were used with different (Si-C) samples. The alpha-SiC(0001) surface of industrial silicon carbide crystals, a (Si-C) compound resulting from the implantation of carbon at 30 keV into a silicon substrate and beta-SiC layers formed by evaporation of carbon on Si(111) at 1080 degrees C were analysed. Characteristic Si-LVV and C-KVV Auger spectra of band type structure, recorded in N(E) mode, are related to silicon carbide. These spectra are detected from alpha-SiC, beta-SiC layers and from the substrate layers of the implanted samples as revealed after argon ion beam etching. Heat treatment of the samples in UHV induced the formation of excess carbon at the surface. The Auger and loss spectra of such a C-rich surface are compared to those of pure graphite.