High frequency power switch - improved performance by MOSFETs and IGBTs connected in parallel

For many high power applications semiconductors are desirable which combine the excellent switching characteristics of a MOSFET with the good conducting behaviour of an IGBT. This paper presents hybrid power switches for higher frequencies with an improved performance based on the parallel connection of corresponding MOSFETs and IGBTs. The objectives are to combine the advantages of both the unipolar and the bipolar power semiconductors by avoiding the drawbacks of these different semiconductor types. The proposed hybrid power switches have been analyzed in a hard-switching converter under different operation conditions as well as in a ZVS inverter with resonant load. For this different IGBT types have been connected in parallel to super-junction MOSFETs. The performances of the resulting power switches depend strongly on the chip structure and the conductivity modulation of the bipolar devices. In this paper these dependencies and their effects have been taken into account.