NUMERICAL STUDY OF OHMIC-SCHOTTKY CARBON NANOTUBE FIELD EFFECT TRANSISTOR

MOS-like transistors are one of the transistor topologies based on the carbon nanotubes. Some modified structures have been proposed to improve their electrical characteristics, such as band to band tunneling (BTBT) and switching behavior. Unfortunately, most of them increase the transistor length due to the use of additional regions. In this paper, we propose a structure that improves the OFF state and switching behavior of the transistor without increase in the transistor length. The proposed structure is constructed by a modification of the conventional structure in a way that its drain high-doped extension part is replaced by a lightly linear doped region. Then, the proposed structure has a Schottky contact at the drain side. With a nonequilibrium Green's function (NEGF) formalism, we have studied the characteristics of the proposed device and compared them with those obtained by a conventional structure with the same channel length. The results show that the proposed structure enjoys from better switching characteristics and OFF-state behavior, especially at low currents, in comparison to the main structure and, as a result, can be a good candidate for the low-power applications.