The Oppositely Doped Islands IGBT Achieving Ultralow Turn Off Loss

An oppositely doped islands insulated gate bipolar transistor (ODI-IGBT) is investigated for the first time. By adding one or several ODIs in the drift longitudinally equidistantly, the ODI-IGBT obtains a better electric field distribution than the field-stop IGBT (FS-IGBT) at OFF-state, which means a larger breakdown voltage. Moreover, at inductive load turn off transient, its space charge region is wider along with the better electric field distribution. Hence, less excess carriers are left when the anode voltage rises to the bus voltage. That is, its current decaying time is smaller than FS-IGBT, so does the turn off loss. Compared with the FS-IGBT in TSUPREM4 simulation, the ODI-IGBT can achieve a much lower turn off loss, which is only 52% of that of the FS-IGBT at the same breakdown voltage and same ON-state voltage. In addition, the ODI-IGBT has a simpler manufacturing process and better immunity to process deviation than the super junction IGBT (SJ-IGBT).