Experimental study on quasi-ballistic transport in silicon nanowire transistors and the impact of self-heating effects

Abstract

The ballistic efficiency and self-heating effects in gate-all-around silicon nanowire transistors (SNWTs) are experimentally investigated in this paper. A modified experimental extraction method for SNWTs is proposed, which takes into account the impact of source contact resistance. The highest ballistic efficiency is observed in sub-40 nm SNWTs at room temperature, demonstrating their intrinsic potential for near-ballistic transport. However, it is experimentally found that, even if the SNWT is fabricated on bulk-Si substrate, the self-heating effect is comparable or even a little bit worse than SOI devices due to the 1-D nature of nanowire and increased phonon-boundary scattering in GAA structure. Considering heat transport and heating corrections at the drain side, the Lundstrom model is modified, and the impacts of self-heating on quasi-ballistic SNWTs are discussed as well.