Retrograded Channel SOI LIGBTs with Enhanced Safe Operating Area

A retrograded doping profile(RDP) is directly introduced into the lateral diffused channel region for an insulated gate bipolar transistor (RDP-LIGBT) on silicon-on-insulator (SOI) substrate to improve its current capability and robustness. The profile is implemented by ion-implantation with energy less than 180 KeV before gate oxidation. The threshold voltage is well controlled by considering the mask proximity effect (MPE). The new LIGBT has a current capability of 1.2-1.6 times larger than that of its conventional counterpart. Its short-circuit capability is 1.2 J/cm 2 , while its conventional counterpart's is 0.192 J/cm 2 , at a voltage of 180-210 V and a current density of 1.4 KA/cm 2 .