An accurate prediction of two-dimensional carrier density profile in IGBT and its significances on steady-state and transient analysis

This work presents a piecewise two-dimensional steady-state analytical model for insulated gate bipolar transistor (IGBT). The proposed model can accurately describes the dependence of carrier density profile on the ratio of accumulation gate width (L_g) to the half cell width (L_cell) without ignoring the recombination in the drift region. The drift region of IGBT is divided into four regions in this model. By determining the boundary that separates one- and two-dimensional regions, the carrier density profiles in the four regions can be derived with proper boundary conditions. The model is originally developed for, but not limited to, 4H-SiC p-IGBT. The results of proposed model are in good agreement with the simulation results at varied current densities and with different values of L_g/L_cell. The I-V curves in the linear region generated by the proposed model match well with the simulated results. The error of the amount of stored charge generated by one-dimensional model will also be examined.