Ballistic quantum transport in nano-scale Schottky barrier tunnel transistors

Nanoscale Schottky barrier tunnel transistors (SBTTs) are investigated by solving the two-dimensional Poisson equation self-consistently with ballistic quantum transport equations. We have analyzed the device characteristics of SBTT by varying the device parameters such as the channel length, tunnel barrier height, and gate insulator dielectric constant. We have found that on-current is almost independent of the channel length while off-current drastically increases as the channel length becomes shorter than around 15 nm. Discussions on avoiding such large off-current are presented, in terms of adjusting the Schottky barrier height and using a gate insulator with high dielectric constant.