Microwave Characterisation And Modelling Of Silicon Carbide Power Mesfets: Towards A Nonlinear Model

SiC power MESFETs are studied for applications to power amplification in the microwave domain. A small-signal model is explained. It provides the intrinsic bias-dependent parameters of the devices, such as G(m), C-gs, C-ds, C-gd, and the current gain cut-off frequency f(T). It is shown that f(T) and G(m) decrease with the drain to source bias V-DS, because of self-heating effects. The model also includes temperature dependence and is in good agreement with experiments. This is a first step to non-linear modelling of SiC MESFETs.