Optimization of the source field‐plate design for low dynamicR_DS‐ONdispersion of AlGaN/GaN MIS‐HEMTs

AlGaN/GaN MIS‐HEMTs with two levels of source field‐plates were studied by means of pulsedI–Vmeasurements. These measurements showed that the presence of a source field‐plate itself is not enough to guarantee a low dynamicR_DS‐ONat high OFF‐state drain‐bias. Simulations of the electric field were carried out to explain the experimental results. It was found that not only does the intensity of the electric field affects the dynamicR_DS‐ON, but also that the position of the electric field peaks plays a role in the trapping phenomenon, responsible for the dynamicR_DS‐ONincrease at high OFF‐state drain‐bias. These results show that the source field‐plate must be carefully designed in order to obtain a low dynamicR_DS‐ONat high bias.