Analysis on device structures for next generation IGBT

In recent years, IGBT performances have improved dramatically, and IGBT application fields have expanded widely, especially in high power applications. It is reported that the trench gate IGBT has superior power loss characteristics compared to the conventional planar gate IGBT. However, the trench gate is not the only potential solution for future device structures, because the performance of the planar gate IGBT has not yet reached its limit. There are some factors to be considered when determining device technology for future devices in practical applications, and there are some drawbacks of the trench gate IGBT, including: (1) excessive overcurrent under a short circuit because of the higher transconductance; (2) more complex wafer process technologies and relatively low yields; (3) poor gate oxide quality. In this paper, the possible device geometry design aspects for future high performance 600 V IGBTs are discussed.