Review of Threshold Voltage Modeling for Nitride Recessed-Gate FinFETs under Thermal Effects

Abstract

The nitride-based (for instance, GaN) recessed gate FinFET has potential applications in the high frequency and high power sectors owing to its large bandgap properties and excellent channel controllability. Nevertheless, the problem of self-heating caused by the downsizing of the devices results in the drift of threshold voltage. This paper systematically reviews the current research status of threshold voltage modeling for nitride recessed-gate FinFETs under thermal effects. First, key domestic and international achievements in self-heating effect characterization, recessed-gate technology, and threshold voltage modeling are summarized. Second, the regulation rules of structural parameters and heat dissipation schemes on thermally induced threshold voltage drift are generalized, establishing key quantitative relationships: every 10 nm increase in recess depth causes a positive threshold voltage shift of 30–50 mV, and a high-thermal-conductivity substrate can reduce the hot-spot temperature in the channel by 20–30 K. Finally, deficiencies in current research are analyzed, including insufficient revelation of thermoelectric coupling mechanisms, lack of multiphysics modeling, and inadequate quantification of process-induced thermal damage. This paper points out that future efforts should focus on thermoelectric co-modeling and optimization of thermal management structures, providing theoretical support and engineering references for accurate threshold voltage modeling and device structure optimization of nitride recessed-gate FinFETs under thermal effects.