Electronic properties of a 3C∕4H SiC polytype heterojunction formed on the Si face

The authors report on the electronic properties of a rectifying Si face 3C∕4H SiC heteropolytype junction on n+ 4H SiC. Capacitance-voltage profiling of the junction at temperatures from 4–300K showed high apparent carrier concentration. A semiclassical model was used to explain the behavior. The model predicted a spontaneous polarization-induced valence band quantum well in the 3C, indicating a polarization charge of 9.7×1012cm−2 for 4H SiC, in good agreement with theory. The formation of a two-dimensional hole gas was predicted. Using a Poisson-Schrödinger solver to analyze the measurements, it was found that large (∼3.5×1012cm−2) mobile hole charge was induced in the n-doped 3C SiC.