SB Explains CNFET Performance Dependence on Diameter and Metal Contact

Due to exceptional electrical properties and high carrier mobility, there has been significant interest in exploring the potential of carbon nanotubes (CNTs) as building blocks in future applications of nanoelectronics, such as the use of carbon nanotube field-effect transistors (CNFETs) as Schottky Barrier (SB) devices. However, CNFETs have yielded large on-current (II") variations ranging from 10-5 A to 10-8 A with similar device geometries, and there has been no dear conclusion as to the origin of these variations. Recently, Z. Chen from the IBM T.J. Watson Research Center in New York, J. Knoch from the Institute of Thin Film and Interfaces and the Center of Nanoelectronic Systems in Jiilich, Germany, and their colleagues have demonstrated that the optimum performance of the CNFET devices depends upon a combination of the diameter of a single-walled CNT and the type of metal contact and have produced a model that accounts for the observed current variations.