High channel mobility in 4H-SiC N-MOSFET using N2O oxidation combined with Boron diffusion treatment

Abstract

A new gate oxide configuration, including a Boron treatment, is reported in this work. It is designed to improve the SiO2/SiC interface quality in 4H-SiC N-MOSFETs. The obtained results show high field effect mobilities up to 160 cm2/Vs. The fabricated devices have also been undergone to a BSI stress up to 20 h at room temperature showing good threshold voltage stability. The physical (SIMS) analysis of the oxide and SiC surface reveals that Boron has not diffused into the SiC.