Trap-suppressed channel temperature measurement and thermal resistance characterization model for GaN HEMTs

Abstract

This study proposes a hybrid ultraviolet (UV) electrical characterization method for the precise evaluation of channel temperature (Tch) and thermal resistance (Rth) in gallium nitride-based high electron mobility transistors. In terms of experimental design, by employing UV irradiation to suppress the influence of surface trap effects, the temperature-dependent variation of drain current (Id) is ensured to primarily reflect self-heating phenomena. Based on this approach, high-accuracy of thermal resistance extraction was obtained. Furthermore, in terms of data processing, this work optimizes the conventional Rth calculation equation, demonstrating significantly high consistency between computational results and experimental data. A quantitative relationship between Tch and power dissipation (Pd) was derived, enabling the acquisition of continuous temperature values and Rth characteristics under various bias conditions. This research provides more reliable theoretical foundations and experimental methodologies for thermal management design and performance optimization of such devices.