Assessing RF/AC Performance and Linearity Analysis of NCFET in CMOS-Compatible Thin-Body FDSOI

The ever-growing exploration of negative capacitance field effect transistors (NCFETs) for low-power digital application and recent integration in the advanced technology node calls for an investigation of NCFET technology in radio-frequency (RF) applications featuring metal ferroelectric insulator semiconductor (MFIS) configuration. In this article, through TCAD simulation study, we investigate the RF/ac performance of NCFETs by well-known performance metrics such as short-circuit unity current gain frequency or cutoff frequency ${f}_{T} $ , transconductance generation factor ${g}_{m}/{I}_{d}$ , and transconductance frequency product ${g}_{m} {f}_{T}/{I}_{d}$ , a measure of RF performance per dc power consumption, where ${g}_{m}$ and ${I}_{d}$ are transconductance and drive current, respectively. It is found that MFIS NCFET fares better when compared to the 14-nm fully-depleted silicon-on-insulator (FDSOI) field effect transistor (FET) as a baseline device, in terms of improved performance in ${g}_{m}/{I}_{d}$ and ${g}_{m} {f}_{T}/{I}_{d}$ . A performance parity in cutoff frequency ${f}_{T}$ is observed. Additionally, the intermodulation distortion $\text {IMD}_{{3}}$ and transistor-level linearity are studied. When a qualitative analysis of the behavior of the key linearity metrics such as higher-order harmonics ( ${g}_{m{2}}, {g}_{m{3}} $ ), second- and third-order voltage intercept points ( $\text {VIP}_{{2}}, \text {VIP}_{{3}} $ ), third-order power-intercept point ( $\text {IIP}_{{3}} $ ) is carried out, NCFETs fared comparatively better in linearity. Our conclusions would provide a better insight into adopting NCFET technology for RF applications.