Modeling and Performance Investigation of the Double-Gate Carbon Nanotube Transistor

In this letter, we propose a semiclassical model for the performance investigation and optimization of the double-gate carbon nanotube field-effect transistor (DG-CNTFET). The DG-CNTFET is effective in controlling the ambipolar conduction that is inherent to Schottky barrier (SB) CNTFETs using two independent gates, namely, the primary gate and the polarity gate. Whereas the primary gate serves to turn the device on and off, the polarity gate can be used to configure the device in either the p-type or the n-type mode of operation. The DG-CNTFET exhibits unipolar conduction and can achieve a large ratio of over six orders of magnitude. Since the proposed model is physics based and does not rely on fitting parameters, it can be used to study the effect of parameters such as CNT chirality, SB height, and gate dielectric thickness on the DG-CNTFET performance.