Advanced carrier density enhancement technologies in insulated gate bipolar transistors

Continuous efforts have been made to improve the IGBT performance, especially in terms of the trade-off between the on-state voltages and turn-off energy losses. Recently the carrier density enhancement (CDE) technologies, which aim at increasing the carrier densities near the emitter/cathode side of the IGBTs, are of great interest to the industry. In this paper, an insight introduction of the state-of-the-art CDE technologies is provided. In addition, a novel dual-gate trench IGBT which utilises an embedded low-gain PNP and thyristor to achieve an ultra-low on-state voltage without deteriorating the switching speed is presented.