Scalable Multi‐harmonic Large‐Signal Model for AlGaN/GaN HEMTs Including a Geometry‐Dependent Thermal Resistance

scalable large-signal model of Al- GaN/GaN High electron mobility transistors (HEMTs) suitable for multi-harmonic characterizations is presented. This model is fulfilled utilizing an improved drain-source current (Ids) formulation with a geometry-dependent thermal resistance (Rth) and charge-trapping modification. The Ids model is capable of accurately modeling the highorder transconductance (gm), which is significant for the prediction of multi-harmonic characteristics. The thermal resistance is identified by the electro-thermal Finite element method (FEM) simulations, which are physically and easily scalable with the finger numbers, unit gate width and power dissipations of the device. Accurate predictions of the quiescent currents, S-parameters up to 40GHz, and large-signal harmonic performance for the devices with different gate peripheries have been achieved by the proposed model.