Impact of ambient temperature on CombFET for sub-5-nm technology nodes: An RF performance perspective

Abstract

This paper explores the impact of ambient temperature on the RF performance parameters of CombFET device. The CombFET has been considered one of the most realistic alternatives for investigating high frequency applications at sub-10-nm technology nodes. CombFET offers a higher drive current than existing gate-all-around (GAA) nanosheet FET (NSFET) under the same footprint. By taking into account the temperature range of military applications (280 to 400 K), the effect of ambient temperature on the device’s electrical performance is addressed. Further, the RF performance of the device is demonstrated at various ambient temperatures as well as various crucial metrics like transconductance (g_m), TGF, h₂₁, f_T, and TFP are analyzed. Moreover, the zero temperature coefficient (ZTC) operating points are identified from the well calibrated simulation results. The ZTC drain drive current is observed at a gate biasing of 0.77 V, for an applied drain biasing (V_DS) of 1 V. The observed drain drive current for different ambient temperatures is observed to be 28μA (V_DS = 1 V). Also, at the ZTC point, the observed g_m value is 0.094mS (V_DS = 1 V). These findings will therefore provide performance insights into the CombFET device's response to thermal changes.