Impact of Field-Plate Structure on Parasitic Effects in GaN Based Transistor

In this paper, the impact of different field plate (FP) techniques on parasitic effect in GaN High Electron Mobility Transistor (HEMT) is investigated. TCAD physical simulation is carried out to analyze the performance of various field plate such as gate, source and gate-source field plate. In addition, simulation results are validated by means of measured data of
$400\times 10 \ \mu \mathrm{m}$
GaN-HEMT and the equivalent circuit small-signal modeling (SSM). In general, the extracted parameters through the SSM and TCAD simulation are almost consistent in characterizing the effect of the FP. It is found also that the gate-connected field plate provides optimal performance with lower parasitic effect. This work contributes in improving the RF performance of the device by means of optimizing the device structure.