Trends in power semiconductor devices

This paper reviews recent trends in power semiconductor device technology that are leading to improvements in power losses for power electronic systems. In the case of low voltage (<100 V) power rectifiers, the silicon P-i-N rectifier has been displaced by the silicon Schottky rectifier, and it is projected that the silicon TMBS rectifier will be the preferred choice in the future. In the case of high voltage (>100 V) power rectifiers, the silicon P-i-N rectifier continues to dominate but significant improvements are expected by the introduction of the silicon MPS rectifier followed by the GaAs and SiC based Schottky rectifiers. Equally important developments are occurring in power switch technology. The silicon bipolar power transistor has been displaced by silicon power MOSFET's in low voltage (<100 V) systems and by the silicon IGBT's in high voltage (>100 V) systems. The process technology for these MOS-gated devices has shifted from V-MOS in the early 1970's to DMOS in the 1980's, with more recent introduction of the UMOS technology in the 1990's. For the very high power systems, the thyristor and GTO continue to dominate, but significant effort is underway to develop MOS-gated thyristors (MCT's, EST's, DG-BRT's) to replace them before the turn of the century. Beyond that time frame, it is projected that silicon carbide based switches will begin to displace these silicon devices.