Activation energy for the post implantation annealing of 1019cm-3 and 1020 cm-3 ion implanted al in 4H SiC

The activation energy for the electrical activation of 1×1019 cm-3 and of 1×1020 cm-3 ion implanted Al in 4H-SiC has been estimated. Ion implantation temperature and dose rate were in the range 430-500°C and around 1011 cm-2s-1, respectively. Post implantation annealing temperatures varied between 1500 °C and 1950 °C. The annealing time per each annealing temperature was sufficiently long that the sheet resistance of the implanted layer could be equal to the stationary value at the applied annealing temperature. The Arrhenius plots of the room temperature sheet resistance with respect to the post implantation annealing temperature featured an exponential trend for both implanted Al concentrations. The correspondent activation energies are the energy required to place an implanted Al atom in a substitutional lattice site, i.e. the electrical activation energy. Activation energies around 1 eV, equal within errors for the two implanted Al concentrations, were found.