A Novel De-Mirroring Approach for Bias-Dependent Capacitance Extraction in Nanosheet Fet Using Conformal Mapping

The sheets/channels are vertically stacked in Nanosheet FET (NSFET), which forms a complex capacitive network. Till date, to the best of our knowledge, the only biasindependent capacitance model for NSFET has been presented by considering that the device is mirrored symmetric around the center of the channel. This mirroring approach does not precisely address the nominal biasing conditions at the source and drain; thus, we need to model the two halves separately. In this paper, we propose a biasdependent (i.e., drain voltage (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{V}_{\text{DS}}$</tex>) dependent) capacitance extraction of an NSFET using a de-mirroring approach. The electric field coupling from the drain to the source impacts the capacitances. The obtained results reveal that the mirroring approach overestimates the capacitances by <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\sim 15 \%$</tex>, which is accurately predicted by our proposed de-mirroring approach.