A Snapback-Free and Process-Compatible Reverse-Conducting IGBT with an Embedded Buffer

A snapback-free and process-compatible reverse-conducting insulated gate bipolar transistor (RC-IGBT) is proposed and investigated. It features the embedded N-buffer layer introduced by high-energy ion implantation in the drift region. The mechanism, process flow and its simulation validation are presented. In forward conduction, this design facilitates electronic current flow through the increased collector short resistance in unipolar mode, effectively eliminating the snapback effect without compromising other characteristics. Simulation results show the proposed snapback-free RC-IGBT achieves forward voltage drops of 1.49 and 2.09 V forward voltage drop at
J
_C
= 100 and 200 A/cm
²
, and ON-state voltage of 1.6 V for the integrated FWD at 150 A/cm
²
with 52 μm half-cell pitch. The fabrication process for the proposed device is simple and compatible with current manufacturing processes. These demonstrated device performances, as well as the simple structure make our proposed device highly attractive in future high performance applications.