An Analytical Model of the Switching Behavior of 4H-SiC p+-n-n+ Diodes from Arbitrary Injection Conditions

An analytical model of the switching behavior of SiC diodes is presented. The model gives an accurate description of the current and voltage transient for a wide range of reverse to forward current ratios and allows one to evaluate the spatial-temporal distributions of carriers density, current components and electric field along the base at a generic instant of the whole transient. Using this model, a large-signal circuit is derived that is useful for circuital analysis of diode under generic operation conditions. The accuracy of the model is verified by comparisons with numerical simulations and experimental results