Coulomb-limited mobility in 4H-SiC MOS inversion layer as a function of inversion-carrier average distance from MOS interface

Abstract

Abstract The Coulomb-limited mobility ( μ Coulomb ) of Si-face 4H-SiC MOSFETs with nitrided gate oxide is experimentally evaluated. μ Coulomb is experimentally determined using samples with various acceptor concentrations by varying the body bias. It is found that the depletion-charge and surface-carrier densities in the inversion layer can be utilized to well formulate μ Coulomb . In addition, μ Coulomb is investigated as a function of the inversion-carrier average distance from the MOS interface ( Z AV ), and it is established that Z AV can universally describe μ Coulomb in the inversion layer of Si-face 4H-SiC MOSFETs with nitrided gate oxide.