A Snapback-free RC-IGBT with Si3N4 Trench and P-type Pillar

A novel structure of reverse conduction insulated gate bipolar transistor (RC-IGBT), which can be applied to 1200V IGBT modules, has been proposed. It features a Si
₃
N
₄
trench placed between the n-collector, the p-collector and a p-pillar upon the Si
₃
N
₄
trench. The novel structure introduces a high-resistance collector short resistor at low current density, which leads to the suppression of the snapback effect. The collector short resistance can be adjusted by varying the length, width and concentration of the p-pillar without increasing the collector cell length. The simulation results show that the proposed novel structure can eliminate the voltage snapback effect and has a better relationship with the forward voltage drop and the turn-off loss of IGBT devices.