Numerical Analysis for a P-Drift Region N-IGBT With Enhanced Dynamic Electric Field Modulation Effect

This article studies the underlying physical mechanism and comprehensive characteristics of the N-channel IGBT (N-IGBT) with P-drift region (PD-IGBT). Distinguishing from the conventional N-IGBT with N-drift region (ND-IGBT), the main blocking junction ( $J_{MB}$ ) of the PD-IGBT is changed from the emitter side to the collector side, which leads to a significant enhancement effect of dynamic electric field modulation. Based on the effect, the PD-IGBT features fast dynamic electric field (E-field) building speed in the drift region and a high E-field at the edge of the field-stop (FS) layer, which can extract excess carriers stored in the device rapidly during the turn-off transient, thus reducing the turn-off loss ( $E_{{off}}$ ) and turn-off time ( $t_{{off}}$ ) of the device. Moreover, the change of $J_{MB}$ location can also alleviate the E-field crowding phenomenon at the trench gate corner, thus providing an optimized relationship between breakdown voltage (BV) and on-state voltage, as well as high avalanche energy. Simulation results show that, when compared with the state-of-the-art N-channel ND-IGBT, the PD-IGBT offers 46% shorter $t_{{off}}$ , 57% lower $E_{{off}}$ , and 60% larger avalanche energy without compromising other device characteristics.

Automated summary

This article studies the physical mechanism and characteristics of the N-IGBT with PD-IGBT. By changing the main blocking junction from the emitter side to the collector side, the PD-IGBT enhances the dynamic electric field modulation and reduces turn-off loss and time. Moreover, the change in location of the blocking junction also optimizes the relationship between breakdown voltage and on-state voltage, leading to higher avalanche energy.