Hall effect measurements at low temperature of arsenic implanted into 4H-silicon carbide

The arsenic dose dependence of electrical properties for implanted samples at 500°C and subsequently annealed at 1600°C for 30min has been investigated to derivate the activation energies of the arsenic donors in silicon carbide. Hall effect measurements were performed between 20K and 773K. Hall carrier concentration of implanted sample with high dose of 7×10 ¹⁵ cm ^-2 is independence of temperature, which indicates the formation of implanted layer with metallic conduction. For the sample with low dose of 1×10 ¹⁴ cm ^-2, the experimental Hall mobility varies directly as T ^3/2 below 80K and as T ^-3/2 above 150K. The activation energies of arsenic donors determined from the implanted sample with low dose using a least-squares fit of the charge neutrality equation are 66.8 meV for hexagonal site and 127.0 meV for cubic site, respectively.