Reverse-Conducting Insulated Gate Bipolar Transistor: A Review of Current Technologies

The reverse-conducting insulated gate bipolar transistor (RC-IGBT) has several benefits over a separate IGBT and diode solution and has the potential to become the dominant device within many power electronic applications; including, but not limited to, motor control, resonant converters, and switch-mode power supplies. However, the device inherently suffers from many undesirable design tradeoffs which have prevented its widespread use. One of the most critical issues is the snapback seen in the forward conduction characteristic which can prevent full turn-on of the device and result in the device becoming unsuitable for parallel operation (required in many high voltage modules). This phenomenon can be suppressed but at the expense of the reverse conduction performance. This paper provides an overview of the technical design challenges presented by the RC-IGBT structure and reviews alternative device concepts which have been proposed in literature. Analysis shows that these alternate concepts either present a tradeoff in performance characteristics, an inability to be manufactured, or a requirement for a custom gate drive.