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.