Simple method to estimate the shallow interface trap density near the conduction band edge of MOSFETs using Hall effect measurements

Abstract

Abstract A simple method to estimate the shallow interface trap density of states and the energy level of a MOSFET channel is proposed in this paper. This method estimates the trap density of states directly from the surface carrier density in the channel determined by Hall effect measurements, without any combination of the other multiple measurement methods. Fermi–Dirac statistics was applied to calculate the surface carrier density at a certain surface potential. Incomplete ionization of doped impurities in the equilibrium region was also considered for a wide bandgap semiconductor such as SiC. This method was demonstrated using n-channel 4H-SiC MOSFETs and was confirmed to be reasonable as the estimated trap density of states was equivalent to that obtained via a previous method combined with Hall effect and split capacitance–voltage measurements.