Experimental Evaluation of Self-Heating and Analog/RF FOM in GAA-Nanowire FETs

Abstract

In this paper, we report the characterization and modeling of multi-finger gate all around (GAA) nanowire (NW) FETs (NWFETs) from dc to 14 GHz. The self-heating effect (SHE) in NWFETs is investigated experimentally using the small-signal output conductance ( ${g}_{{\text {ds}}}$ ) technique. The frequency-dependent complex thermal impedance, ${Z}_{{\text {th}}}({f})$ , is extracted by fitting an ${n}$ th-order thermal network with the experimental data. We show that the temperature rise $\Delta {T}$ (=85 °C) due to SHE is significant in short-channel silicon on insulator (SOI) NWFETs. Finally, we have evaluated the RF figure of merit (FOM) for these NWFETs as ${f}_{T}$ (=70 GHz) and ${f}_{\text {max}}$ (=80 GHz). We also report the RF performance metric sensitivity on temperature, $\partial {f}_{\text {max}}/\partial {T}_{{\text {amb}}}$ ( $\approx -0.104$ GHz/K). The reported BSIM-CMG compact model shows a good correlation with the measurement data.