Impact of underlap layer on DC and RF/analog performance of asymmetric junctionless dual material double gate MOSFET for low-power analog amplifier design

Abstract

Impact of underlap layer is analytically investigated on asymmetric junctionless dual material double gate MOSFET (AJDMDG) to reduce subthreshold slope and threshold voltage, which are two essential requirements with shrinking device dimensions to avoid short channel effects. The model utilizes two-dimensional Poisson’s equation with parabolic approximation for determining electrical parameters where dimensional ranges are kept within fabrication limit. Excellent accuracy is found for the obtained analytical outcome, when compared with results obtained from TCAD ATLAS simulator. Comparative study is extended for conventional junctionless DMDG (JDMDG) and underlap asymmetric junctionless single material DGFET (UAJDG) device, having identical dimensional parameters and biasing ranges; where the present structure exhibits superior performance in terms of threshold voltage, subthreshold slope and DIBL of 34.57%, 62.85% and 69.85% respectively compared to JDMDG and 12.50%, 26.08% and 40.25% respectively w.r.t UAJDG structure. Supremacy of the proposed architecture is further established with RF/analog Figures of Merit (FOMs), which are essential for designing low power analog amplifier.