Effects of Different Oxide Thicknesses on the Characteristics of CNTFET

The device dimensions have been consistently scaling down since many developing technologies need smaller and faster-integrated circuits for advancement and improvement in both performance and device density. Carbon nanotube field-effect transistor (CNTFET) is one of the promising technologies that able to improve size and speed issues. Carbon Nanotube (CNT) is one of the promising channel materials for FETs. In the CNTFET design process, the thickness of the oxide layer played an important role in the scalability and performance of the transistor. The purpose of this work is to characterize the performance of CNTFET due to scaled oxide thickness. The research is conducted using the CNTFET labtool of nanoHUB.org consists of FETToy Simulator. FETToy 2.0 is based on MATLAB scripts that calculate the ballistic I-V characteristics used to simulate this CNTFET. In this work, the oxide thickness of the CNTFET is a parameter under study and the performance of the CNTFET is analyzed based on the varied oxide thickness. We have investigated the effect of scaling gate oxide thickness on the device performance CNTFET in terms of Ion/Ioff ratio, mobile charge and transconductance. The results show that reducing the oxide thickness can increase the current ratio and transconductance due to increased mobile charges in the transistor. From this study, it is observed that oxide thickness significantly affecting the current ratio of the CNTFET.