Resonant tunneling and hole transport behavior in low noise silicon tri-gate junctionless single hole transistor

Abstract

The fabrication of p-type silicon junctionless tri-gate transistors and their temperature dependent transport studies are reported in this work. The fabricated transistors have shown a good transfer characteristic down to a low temperature of ∼ 80 K with an ON/OFF ratio of 106. The threshold voltage and the subthreshold slope were found to be dependent on temperature. In particular, the threshold voltage and the flat band voltage have positive slopes of 2.24 and 1.19 mV K−1, respectively, with temperature. Channel resistance was found to be increasing with decreasing temperature. The devices have shown a typical 1/f noise behavior in the frequency range of (1–50) Hz and 1/f2 type behavior in the frequency range of (50–100 Hz). At a temperature of 4.2 K, current vs. gate voltage characteristic at a fixed source drain bias shows clear coulomb peaks with different intervals for different gate bias voltages and the observed spikes were consistent within the sub-bands. We relate this to the single hole tunneling, mediated by the charged acceptors available in the channel region. Coupling strength of the dopants was also studied.