Inversion layer injection devices from concept to applications in HVICs

This paper reviews the concept of inversion layer injection from the band diagrams to full fabrication and application in the area of high voltage integrated circuits. Inversion layer injection devices range from vertical trench gate structures where the inversion layer is used as a thyristor emitter, to lateral devices in power integrated circuits where the inversion layer is used as a p-type injector in the anode junction of LIGBT-like structures. When applied to lateral devices the concept delivers smooth I-V characteristic without trading off the on-state against transient losses and thus achieving very high frequency capability (in excess of 100 KHz for 500 V devices). Therefore such devices are particularly attractive for emerging high voltage integrated circuits where achieving a high current density with minimum overall losses is essential.