Room-Temperature Observation of Negative Differential Conductance Due to Large Quantum Level Spacing in Silicon Single-Electron Transistor

Abstract

We have observed for the first time negative differential conductance (NDC) at room temperature in a silicon single-electron transistor (SET). The device is in the form of an ultranarrow wire channel metal oxide semiconductor field-effect transistor (MOSFET), which acts as a multiple-dot SET and shows large Coulomb blockade oscillations at room temperature. In the finite drain-bias characteristics, double-peak negative differential conductance (NDC) is observed even at room temperature. The reason behind the observed characteristics is considered to be the interplay between the resonant tunneling through a discrete quantum level in the ultrasmall dot and the classical Coulomb staircase effect in another dot.