Ion implantation in 4H–SiC

Silicon carbide offers unique applications as a wide bandgap semiconductor. This paper reviews various aspects of ion implantation in 4H–SiC studied with a view to optimise ion implantation in silicon carbide. Al, P and Si ions with keV energies were used. Channelling effects were studied in both a-axis and c-axis crystals as a function of tilts along major orthogonal planes and off the major orthogonal planes. Major axes such as [0 0 0 1] and the [112¯0] and minor axis like the [112¯3] showed long channelling tails and optimum tilts for minimising channelling are recommended. TEM analyses of the samples showed the formation of (0 0 0 1) prismatic loops and the (112¯0) loops as well,in both a and c-cut crystals. We also note the presence of voids only in P implanted samples implanted with amorphising doses. The competing process between damage accumulation and dynamic annealing was studied by determining the critical temperature for the transition between crystalline and amorphous SiC and an activation energy of 1.3 eV is extracted.