High-mobility SiC MOSFET with low density of interface traps using high pressure microwave plasma oxidation*

Abstract

The microwave plasma oxidation under the relatively high pressure (6 kPa) region is introduced into the fabrication process of SiO2/4H-SiC stack. By controlling the oxidation pressure, species, and temperature, the record low density of interface traps (∼ 4 × 1010 cm−2⋅eV−1@Ec − 0.2 eV) is demonstrated on SiO2/SiC stack formed by microwave plasma oxidation. And high quality SiO2 with very flat interface (0.27-nm root-mean-square roughness) is obtained. High performance SiC metal–oxide–semiconductor field-effect transistors (MOSFETs) with peak field effect mobility of 44 cm−2 ⋅eV−1 is realized without additional treatment. These results show the potential of a high-pressure plasma oxidation step for improving the channel mobility in SiC MOSFETs.