From Gate-all-Around to Nanowire MOSFETs

The classical MOSFET is reaching its scaling limits and "end-of-roadmap" alternative devices are being investigated. Amongst the different types of SOI devices proposed, one clearly stands out: the multigate field-effect transistor (multigate FET). This device has a general "wire-like" shape. Multigate FETs are commonly referred to as "multi(ple)-gate transistors", "FinFETs", "tri(ple)- gate transistors", "GAA transistors", etc. This paper describes the reasons for evolving from single-gate to multi-gate structures. It also describe some issues in ultra-small devices, such as doping fluctuation effects and quantum confinement effect.