Simulations of the CNFETs using different high-k gate dielectrics

Ankita Dixit,Navneet Gupta

doi:10.11591/eei.v9i3.1784

Abstract

In this paper we presented the analysis of Carbon Nanotube Field Effect Transistors (CNFETs) using various high-k gate dielectric materials. The objective of this work was to choose the best possible material for gate dielectric. This paper also presented the study on the effect of thickness of gate dielectric on the performance of the device. For the analysis (19, 0) CNT was considered because the diameter of (19, 0) CNT is 1.49nm and the CNFETs have been fabricated with the CNT diameter of ~1.5nm. It has been observed that La2O3 is the best gate dielectric material followed by HfO2 and ZrO2. It was also observed that as thickness of gate dielectric material reduces, drain current of CNFET increases. The outcomes of this study matches with the analytical results and hence confirm the results

Highlights

For many years, silicon (Si) has been used as a basic material in the fabrication of transistors, the problem associated with attempting to scale down traditional semiconductor devices (Si- MOSFET) have led researchers to look into other material d evices such as carbon nanotube field effect transistors (CNFETs) as alternative
In order to get the best gate dielectric material for CNFET, transfer characteristics and output characteristics have been analyzed for different gate dielectric materials
The variation of Id with respect to Vgs for various gate dielectric thickness (Tox) (i.e. 3nm, 5nm, 7nm, 8nm, 10nm, 20nm) with gate dielectric material La2O3 and HfO2 is shown in Figure 8 and Figure 9, respectively. It has been observed from the plots that the current on/off ratio increases with decreases the thickness of gate dielectric material

Summary

Introduction

Silicon (Si) has been used as a basic material in the fabrication of transistors, the problem associated with attempting to scale down traditional semiconductor devices (Si- MOSFET) have led researchers to look into other material d evices such as carbon nanotube field effect transistors (CNFETs) as alternative. Carbon nanotubes (CNTs) have been the subject of a lot of scientific research in recent years, due to their small size and because of their remarkable mechanical properties, electronic (high mobility, high transconductions and high current density) properties [1] and many potential applications [2, 3]. Based on the chirality, CNTs can be classified into two types: chiral CNT and achiral CNT. Achiral CNT is further divided into Zigzag CNT and Armchair CNT. The diameter (d) and energy band gap (Eg) of CNT is calculated by following (1-2) [4]:

Objectives

Results

Conclusion