Influence of Underlap on Gate Stack DG-MOSFET for analytical study of Analog/RF performance

Abstract

In this paper , the characteristics of 18 nm Underlap Double Gate (U-DC ) NMOSEFT with gate stack, (GS) are presented. The high-k dielectric as gate insulator under consideration is Hafnium Dioxide (HfO2). The SiO2 padding reduces the effect of scattering at the silicon and oxide interface. The ratio of on current to off current is used for optimizing the underlap length . The Analog and RF performance comparison are shown in this paper considering the drain current , the transconductance , the intrinsic resistences, the transport delay , the intrinsic inductence , the unity current gain cut off frequency and the maximum frequency oscillation . RF parameters are extracted using the Non Quasi Static (NQS) model of the u-DG MOSFET. The performance of single stage amplifiers using the devices is also analyzed . The sharpest transition is shown in case of U-DG-GS MOSFET with optimized underlap length and enhancement in the intrinsic capacitances and resistances and unity Gain Bandwidth product in case of devices with GS