Sub-10 nm junctionless carbon nanotube field-effect transistors with improved performance

Abstract

Carbon nanotube field-effect transistors (CNTFETs) and their growing applications are becoming part of modern nanoelectronics, which is in urgent need for high-performance ultrascaled transistors. Sub-10-nm junctionless ballistic carbon nanotube field-effect transistors (JL-CNTFET) with substantial improved performance are computationally proposed herein. The non-equilibrium Green's function (NEGF) simulation is used for the computational assessment. The proposed simple improvement technique is based on the use of high n-type doping concentration at the level of carbon nanotube underneath the gate while keeping the junctionless paradigm that facilitates tremendously the fabrication processes of ultrascaled FETs. It has been found that the proposed doping profile can significantly mitigate several ultrascaling effects while boosting the performance of sub-10-nm JL-CNTFETs. The recorded enhancements include the leakage current, current ratio, subthreshold swing, switching speed, switching energy, drain-induced barrier lowering, and threshold voltage roll-off. The significant improvements obtained in this work for sub-10-nm JL-CNTFETs, make the proposed strategy, which is simple, feasible, and efficient, as a promising technique for improving ultrascaled FETs endowed with other gate geometries and channel nanomaterials while paving the way towards high-performance sub-5-nm FETs.