Small-Signal Impedance and Split C-V Characterization of High-κ SiC Power MOSFETs

Abstract

In this work, the improvement of SiC power MOSFET performance achieved using high-κ gate-dielectrics instead of the standard SiO2 is investigated by means of advanced gate-impedance characterization. The benefit of using high-κ gate-dielectrics with high dielectric constant is demonstrated by comparing SiC MOSFETs with pure high-κ, a stack of SiO2/high-κ, as well as pure SiO2. Namely, the fabricated high-κ SiC MOSFETs show a superior performance to commercial SiC MOSFETs with SiO2/SiC interface with respect to channel resistance and interface quality. The proposed characterization approach is non-destructive and applicable to packaged power devices.