| Abstract |
Theoretical considerations and modelling calculations on switching properties of sic devices are presented, and a comparison with sillicon devices at room temperature is given. Figures of merit are described Which are significant for the design as well as for the range of applicability. As essential figure of merit considering on-state and switching properties, the ratio of on-conductance to the stored charge is introduced. A trade-off relation between on-state and turn-off losses of MOSFETs is derived, which is very advantageous for Sic as represented by this figure of merit. The reverse recovery behaviour of Schottky-diodes is calculated, using the cubic polytype B-SiC for numerical examples. It is shown, that for given on-state power losses per active device area, the recovery behaviour of Schottky-diodes with a breakdown voltage of 500 V is nearly equal for devices of B-SiC and silicon. The power losses themselves, however, are just as the area smaller for the sic diode by a factor of nearly 4. |
