GaN HEMT model extraction based on dynamic-bias measurements

In this paper a recently proposed identification procedure based on exciting the device under test simultaneously with low-frequency (LF) large-signal excitations and a high-frequency tickle tone, is applied for the first time to GaN transistors. It will be demonstrated that the proposed technique allows reaching good prediction capability even when challenging GaN technologies are considered where LF dispersion strongly affects the transistor behavior. A dedicated formulation for the drain-source current generator is used to correctly account for dispersive phenomena. As a case study a 0.25-μm GaN HEMT is considered. The extracted model has been validated through comparison with vector nonlinear measurements carried out at 10 GHz.