Degradation of Off-Phase Leakage Current of FinFETs and Gate-All-Around FETs Induced by the Self-Heating Effect in the High-Frequency Operation Regime

In this article, the influence of the self-heating effect (SHE) on fin-shaped field-effect transistors (FinFETs) and gate-all-around field-effect transistors (GAAFETs) was investigated. The AC analysis with the input of a square pulse at the gate electrode was implemented to estimate the effect of SHE on the leakage current characteristics. The high-frequency operating region from 500 MHz to 50 GHz was simulated for the comparison at each different operating frequency. The high operating frequency indicates that there is not enough time to relieve the heat generated by SHE during the off-phase of the pulse. Thus, as the operating frequency increases, the off-state leakage current induced by SHE increases accordingly. The so-called thermal time constant (τ_TH) was examined for both FinFETs and GAAFETs by comparing the thermal resistance (R_TH) and thermal capacitance (C_TH) to minimize SHE on leakage current in the simulation environment.