Switching behavior method to estimate the intrinsic gate resistance of a transistor by using the gate plateau voltage

This paper proposes a method for estimating the resistance of the gate part of a transistor chip, i.e., intrinsic gate resistance (R _g,in ). The gate-source voltage (V _gs ) transient waveforms generally exhibit a so-called plateau region at the transistor's turning-off. At this region, V _gs at the gate electrode (V _p ) and the current flowing through R _g ,in and R _g,ext (I _g ) are constant, where R _g,ext represents the resistance of the gate driving line out of the transistor. Thus, V _gs = V _p × {R _g,ext /(R _g,in + R _g,ext )}(*) because I _g = V _p / (R _g,in + R _g,ext ) and V _gs = V _p - I _g × R _g,in . If V _gs is measured at the turning-off with various R _g,ext , fitting a line to the data allows Vp and Rg,in to be obtained from the intercept and the slope of the reciprocal version of (*), respectively,, i.e., 1/V _gs = (R _g,in /V _p )×(1/R _g,ext ) + 1/V _p . This method is used to estimate the R _g,in of a trench-gate SiC transistor. The obtained value is different from that provided in the transistor's data sheet; however, the device model with the new R _g,in significantly improves the switching behavior simulation.