Tunneling: The major issue in ultra-scaled MOSFETs

As transistors scale below 10 nm, the numbers of atoms and electrons are countable in the critical device areas. At this scale, quantum mechanical phenomena start playing an important role in the performance of the transistors. One of the major quantum mechanical effects is tunneling; i.e. tunneling between the gate and channel due to the reduction of physical oxide layer thickness and direct tunneling between the source and drain due to scaling down of channel length. This paper discusses these tunneling issues on performance of ultra-scaled transistors based on rigorous atomistic simulations and provides some solutions for scaling based on a quantitative analysis.