Papers by Author: Youichi Makifuchi

Abstract: 4H-SiC(000-1) C-face was oxidized in H₂O and H₂ mixture gas (H₂ rich wet ambient) for the first time. H₂ rich wet ambient was formed by the catalytic water vapor generator (WVG) system, where the catalytic action instantaneously enhances the reactivity between H₂ and O₂ to produce H₂O. The dependence of SiC oxidation rate on the H₂O partial pressure was investigated. We fabricated 4H-SiC C-face MOS capacitor and MOSFET by the H₂ rich wet re-oxidation following the dry O₂ oxidation. The density of interface traps was reduced and the channel mobility was improved in comparison with the conventional O₂ rich wet oxidation.

Abstract: SiC power module with low loss and high reliability was developed by utilizing IEMOSFET and SBD. The IEMOSFET is the SiC MOSFET with high channel mobility in which the channel region is the p-type carbon-face epitaxial layer with low acceptor concentration. Elemental technologies for the high channel mobility and the high reliability of the gate oxide have been developed to realize the excellent characteristics by the IEMOSFET. The SBD was designed so as to minimize the forward voltage drops and the reverse leakage current. For the fabrication of these SiC power devices, the mass production technology such as gate oxidation, ion implantation and following activation annealing have been also developed.