The Electronic Properties of Magnesium, Zinc, Scandium Substitutional Impurities and their Complexes in 4HSiC

The study of acceptor impurities is of great technological interest for silicon carbide (SiC). First, impurities that can compensate n‐type dopants can be an alternative to vanadium for the formation of semi‐insulating SiC films. Second, similarly to diamond, substitutional acceptors and their complexes might play a role in quantum technology. For this reason, a first‐principles study of the electronic properties of two divalent (Mg, Zn) and one trivalent (Sc) impurities is performed. The generalized gradient approximation is employed and the bandgap energy underestimation is overcome by a posteriori corrections. It is found that, with the exception of Mg, all of the investigated defects, substitutional and complexed with either intrinsic defects or n‐type dopants, give rise to donors (acceptors) close to the edge of the valence (conduction) band. In addition, N‐related complexes have the lowest formation energy and are energetically stable, meaning that such defects might arise already during growth. The results are then discussed in the light of the previous experimental and theoretical studies, found in the literature.