We present a detailed study of a superjunction (S J) nanoscale partially narrow mesa (PNM) insulated gate bipolar transistor (IGBT) structure.This structure is created by combining the nanoscale PNM structure and the SJ structure together.It demonstrates an ultra-low saturation voltage (Vce(sat)) and low tu-off loss (Eoff) while maintaining other device parameters.Compared with the conventional 1.2 kV trench IGBT,our simulation result shows that the Vce(sat) of this structure decreases to 0.94 V,which is close to the theoretical limit of 1.2 kV IGBT.Meanwhile,the fall time decreases from 109.7 ns to 12 ns and the Eoff is down to only 37％ of that of the conventional structure.The superior tradeoff characteristic between Vce(sat) and Eoff is presented owing to the nanometer level mesa width and SJ structure.Moreover,the short circuit degeneration phenomenon in the very narrow mesa structure due to the collector-induced barriers lowering (CIBL) effect is not observed in this structure.Thus,enough short circuit ability can be achieved by using wide,floating P-well technique.Based on these structure advantages,the SJ-PNM-IGBT with nanoscale mesa width indicates a potentially superior overall performance towards the IGBT parameter limit.