A Snapback-Free and Reverse Conducting SOI-LIGBT With Self-Adaptive Electron Barriers

- In this work, a snapback-free and fast-switching silicon-on-insulator lateral insulated-gate bipolartransistor (SOI-LIGBT) with reverse conducting (RC) capa-bility is proposed and investigated by TCAD simulations.The proposed device features an anode p-type polysilicontrench (PT) and a p-type doping region between n(+)anodeand n-buffer (PR) named PTR-LIGBT. The PT is directlyconnected to the anode and driven by the anode voltage without any additional control circuits. At the forward con-ducting state, PT and PR will create electron barriers along the electron path. Those dual barriers will block the flow ofelectrons to the n+anode. As a result, by introducing these two structures, the snapback phenomenon is eliminated inthis novel PTR-LIGBT. Moreover, at the RC state, the bar-riers will decrease gradually with the increase of voltage,so that the RC capability is ensured. The simulation results show that, compared with SSA-LIGBT, the reverse recovery time (trr) and reverse recovery charge (Qrr) of the monolithicdiode of PTR-LIGBT are reduced by 65.34% and 18.59%,respectively. VFof PTR-LIGBT is reduced by 16.52% under the same E-off, and V-F of PTR-LIGBT is reduced by 20.63%under the same T-off.