About the hole transport analysis in heavy doped p-type 4H-SiC(Al)

The knowledge of the Hall factor is essential to convert Hall to drift transport data, in order to fit them and reliably evaluate doping and compensation levels of samples. By introducing empirical mass anisotropy factors, reasons are given in favour of a generalized use of the unique experimental evaluation of the Hall factor reported by the literature for p-type 4H-SiC, which has been assessed for an Al acceptor density in the range of 1.8×10 - 2×10 cm. Using such a curve, carrier transport data, taken in Al implanted 4H-SiC for an Al concentration of 5×10 cm after either 2000°C/30s microwave annealing or 1950°C/300s conventional annealing, were analysed through a standard relaxation time approximation model. A slight difference was evidenced in the compensation level of the samples, also resulting in a different ionization energy of the acceptor.