On-Current Degradation in Ultra-Scaled Nanosheet FETs With S/D Underlap Doping
Year: 2025
Type: article
Abstract: Aggressive gate pitch scaling makes it increasingly challenging to control the doping gradient at the source/drain (S/D) extensions. To address this, S/D underlap doping has been proposed as a solution. However, anomalous ID,linsaturation has been experimentally observed in such devices, raising questions about its physical origin. In this work, we investigate the transport physics in ultra-scaled nanosheet FETs by solving the Subband Boltzmann Transport Equation. The simulation results reveal that secondary barriers formed in underdoped S/D extensions enhance quasi-ballistic transport even in the linear regime, providing a consistent explanation for the observed ID,linsaturation in underlap devices. These insights offer guidance for optimizing S/D underlap doping profiles, highlighting the need to avoid excessive Gate-S/D overlap capacitance while preventing on-current degradation.
Source: IEEE Electron Device Letters
Authors: Lee-Chi Hung, Zlatan Stanojević, Franz Schanovsky, Hans Kosina, Markus Karner
Institution: TU Wien
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,645
OpenAlex ID: W7083291415