Hall mobility and free electron density at the SiC/SiO2 interface in 4H–SiC

The electron mobility and free electron density have been measured in 4H– and 6H–SiC metal-oxide-semiconductor inversion layers using the Hall effect. The 4H–SiC inversion layers are found to have very poor conductance which is caused by severe trapping of electrons at the Si/SiO2 interface. The trapping causes reduced conductance through a reduction in the number of free electrons in the inversion layer, and also because of a drop in the mobility due to increased Coulombic scattering.