Design Insights of Nanosheet FET and CMOS Circuit Applications at 5-nm Technology Node
V. Bharath Sreenivasulu, Narendar Vadthiya
Abstract
In this article, FinFET, vertically stacked gate-all-around (GAA) nanowire (NW), and nanosheet (NS) FETs performance are estimated with equal effective channel widths ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${W}_{eff}$ </tex-math></inline-formula> ) at the 5-nm technology node (N5). The comparison reveals that NS FET exhibits the highest ON current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ), the lowest OFF current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle OFF}}$ </tex-math></inline-formula> ), and the largest <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ </tex-math></inline-formula> ratio with better subthreshold performance. We also explore the geometrical variation of the NS FET toward better dc and analog/RF applications and outlined the necessary design guidelines. Moreover, the robustness of NS FET for temperature variations is also performed and analyzed. Finally, the effect of NS width ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{NS}_{W}$ </tex-math></inline-formula> ) on common source (CS) amplifier, CMOS inverter, and ring oscillator circuits is performed by the Verilog-A model in the CADENCE simulator. An increment of 45.11% in oscillation frequency ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{osc}$ </tex-math></inline-formula> ), 155.5% rise in CS amplifier gain, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.5\times $ </tex-math></inline-formula> increment in energy-delay product (EDP), and marginal reduction in inverter noise margin (NM) is noticed with larger <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{NS}_{W}$ </tex-math></inline-formula> . From the result analysis, it is noticed that for sub-5-nm technological nodes, NS FETs exhibit superior performance and ensure fundamental scaling.