Abstract
This paper describes whether a method to connect an external SiC SBD with SiC MOSFET is truly effective or not. Wide gap characteristic makes SiC devices have excellent characteristics; high breakdown voltage, low on-resistance, high heat-conductivity etc. In contrast, the characteristic leads to large forward voltage drop in case of diode application. It means that conduction loss becomes large. SBD has lower conduction loss than PN diode. That is why SiC SBDs are connected with SiC MOSFETs especially in inverter circuits in order to suppress recovery loss. However, the technique is effective for silicon devices but it is not clarified for SiC devices. We confirmed that the recovery suppression method has effective range.
