Significant Improvement of Inversion Channel Mobility in 4H-SiC MOSFET on (1120) Face Using Hydrogen Post-Oxidation Annealing

摘要

Effects of hydrogen post oxidation annealing (H_2 POA) on 4H-silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) with wet gate-oxide on the (1120) face have been investigated. H_2 POA at 800℃ for 30 min results in inversion channel mobility as high as 110 cm~2/Vs due to a reduction of interface-states. In addition, forming a buried channel (BC) region with a nitrogen doping concentration of 5xl0~(15) cm~(-3) under the SiO-2/4H-SiC interface, it has been achieved the highest channel mobility of 216 cm~2/Vs in the BC MOSFET on the (11 20) face.