Performance evaluation of graphene based priority encoder for analog to digital converter application

Abstract

Continuous scaling and performance optimization on transistors, the basic building blocks for every electronic devices are highly anticipated to fulfil the rocketing technology. By 2021, the transistors were manufactured with 5nm-scale technology by a numbers of chip manufacturer, this significantly increase the number of transistor per area in a chip. In the future, 3nm and 1nm technology will be discovered. The continuous size shrinking will impact the performance degradation on the conventional metal-oxide semiconductor field-effect transistors (MOSFETs). The International Roadmap Device Semiconductor (IRDS) have several alternative materials such as silicon nanowire, carbon nanotube (CNT), graphene, graphene nanoribbon (GNR) to continue the journey of continuous scaling. Apart from that, the advance device architecture such as FinFET, Multiple gate MOSFET, Gate-all-around FET, Vertical MOSFET, SOI MOSFET also been introduced. The aim of this work is to design a priority encoder by adopting GNRFETs-based model and FinFET CMOS-based model. Performance on propagation delay, average power, power-delay product (PDP) and energy delay product (EDP) were evaluated between these two models. The designed priority encoder was then implemented into a flash analog to digital converter to evaluate its functionality. All designs and performance evaluations was carried out by using HSPICE simulation software. Through simulation, it is found that the flash analog to digital converter behave accordingly when the GNRFETs-based priority encoder is applied. In addition, the propagation delay exhibit 61% improvement compared to FinFET CMOS counterpart. In terms of PDP and EDP exhibit 57% and 83% improvement respectively. The outcome of this study is intriguing and can be further implement to other application.