Simulation Study of a High-Current and Fast Dual-Gate IGBT Device With High-<inline-formula> <tex-math notation="LaTeX">$K$ </tex-math> </inline-formula> Material

Abstract

We propose a novel method to turn OFF the lateral insulated gate bipolar transistor (LIGBT) device. Contrary to the conventional means, we improve the LIGBT switching speed by boosting the carrier density in the drift region. With the introduction of a high-permittivity material (HK) into a novel LIGBT structure, a parasitic pMOS with an HK dielectric is formed. The electric field from the pMOS source to the gate introduces many more holes into the drift region of the LIGBT, which significantly increases the device current in the ON-state. When the device is about to be turned OFF, extra electrons are rapidly neutralized by the holes in the channel of the pMOS during the transition period. Then, the device is immediately switched OFF through voltage coupling from the pMOS gate. The switching-OFF time of the proposed LIGBT is only limited by the external gate-driving circuit, which can be as short as 5 ns and is almost free of the tail current according to a numerical simulation.