Experimental Investigations on Ballistic Transport in Multi-Bridged Channel Field Effect Transistors

Abstract

Electrical characteristics of multi bridged channel field effect transistor (MBCFET) with various channel lengths (L) ranging from 500 to 48 nm have been investigated. The current-voltage characteristics do not show any sign of short channel effect due to surrounding gate structures. The gate bias power law of the drain saturation current, mobility, and ballistic efficiency as functions of L show mixed features of drift-diffusion and ballistic transport. The channel resistance shows anomalous decrease when L <= 60 nm, which is related with the transconductance overshoot resulted in ballistic transport at small V-DS. Temperature (T) dependence of the 100 nm device shows another type of transport region when T < 40 K, which can be interpreted as the one-dimensional quantum ballistic regime. (C) 2011 The Japan Society of Applied Physics