Tunneling-triggered bipolar action in junctionless tunnel field-effect transistor

We analyse a novel hybrid semiconductor field-effect transistor (FET), known as the junctionless tunnel FET (JL-TFET). We show that a parasitic bipolar transistor action, which is highly undesirable in conventional metal/oxide/semiconductor FETs and junctionless transistors, is the mechanism that activates the JL-TFET ON state. It is found that the sub-threshold slope (SS) in the JL-TFET is strongly dependent on the silicon thickness and a sub-60 mV/decade SS is observed for a thin silicon body only. We further study the JL-TFET design parameters as regards the effects of the control gate workfunction, P-gate workfunction, and isolation region on the JL-TFET characteristics. (C) 2014 The Japan Society of Applied Physics