Large Coulomb-Blockade Oscillations and Negative Differential Conductance in Silicon Single-Electron Transistors with [100]- and [110]-Directed Channels at Room Temperature

Abstract

Single-electron transistors (SETs) in the form of ultranarrow wire channel metal–oxide–semiconductor field-effect-transistors (MOSFETs) in both [100] and [110] directions were fabricated and large Coulomb-blockade oscillations with a peak-to-valley current ratio (PVCR) of as high as 140, which is the highest ever reported in a single-dot-system SET, were observed at room temperature. Clear negative differential conductance (NDC), whose PCVR is also the highest ever reported, has been observed in both directions at room temperature for the first time. The difference in Coulomb-blockade oscillations and NDC characteristics between [100]- and [110]-directed SET is discussed in terms of quantum confinement.