"Insulated gate bipolar transistor (IGBT) with a trench gate structure "

This paper describes an improved IGBT with a trench gate structure, which demonstrates a low forward voltage drop of 1.4 volts at a forward conduction current density of 200A/cm². This device structure was fabricated using a self-aligned process that permits closely spaced vertical trench gates with a unit cell of 8 µm. This allows for a remarkable increase of channel density and elimination of the parasitic JFET effect thus reducing the forward voltage drop significantly. A static latching current density of 2700A/cm²has been achieved in the UMOS IGBT. Two-dimensional computer simulations of the UMOS IGBT has been performed to identify the optimal cell design. This optimal design is predicted to increase the SOA current density by a factor of 4.2 over the state-of-the-art DMOS IGBT at the same forward voltage drop.