Transient model for electrical activation of aluminium and phosphorus-implanted silicon carbide

Abstract

The development of novel electron devices requires a continuous support by process and device simulations in order to improve electrical properties and reduce production costs. However, an accurate description of the electrical properties of impurities in silicon carbide – a key wide bandgap semiconductor for power devices – is currently not available, which significantly limits the predictability of critical fabrication processes. Here, we introduce a transient model for electrical activation of implanted aluminium and phosphorus in silicon carbide to fill this gap. Our results suggest differences between acceptor- and donor-type dopants including activation speed, saturation limit, and activation regions. We predict acceptor and donor concentrations according to the various annealing times, temperatures, and doping concentrations. The results are used for the fabrication of PN-junction diodes, which are characterized and compared with the experimental findings. Finally, we predict improvements of various annealing steps, i.e., increased active concentration, increased carrier concentration, and decreased sheet resistance, and perform a comprehensive comparison with experimental data to evaluate the proposed model.