Coulomb blockade oscillations at room temperature in a Si quantum wire metal-oxide-semiconductor field-effect transistor fabricated by anisotropic etching on a silicon-on-insulator substrate

Abstract

We have developed a very controllable fabrication process of an extremely narrow (∼10 nm) quantum wire metal-oxide-semiconductor field-effect transistor (MOSFET) on a separation-by-implanted-oxygen (SIMOX) substrate using anisotropic etching and selective oxidation technique. The drain current versus gate voltage characteristics show oscillations caused by Coulomb blockade even at room temperature. The oscillations split into several sharp peaks when the temperature is decreased, indicating that the channel is separated by several serial coupled quantum dots and that the quantum levels of these dots correspond to the observed fine peaks.

Single-electron effects in heavily doped polycrystalline silicon nanowires

“…These use either lithographically defined islands 3,4 or multipletunnel junctions created by material/structural disorder effects. 5,6 By contrast, polycrystalline silicon has been somewhat neglected for SET applications despite a greater flexibility of fabrication. Single-electron effects have been observed in devices using polysilicon, 7,8 but these rely on interlayer tunnelling rather than intrinsic polysilicon properties.…”

Double-dot charge transport in Si single-electron/hole transistors

“…At low temperatures and low source-drain bias Si nanostructures do not follow regular MOSFET transconductance characteristics but show rather complex behavior, suggesting transport through multiply-connected dots. Even in devices with no intentionally defined dots (like Si quantum wires [1][2][3][4] or point contacts [5]) Coulomb blockade oscillations were reported. In the case of quantum wires, formation of tunneling barriers is usually attributed to fluctuations of the thickness of the wire or of the gate oxide.…”

Single-Electron Charging Phenomena in Nano/Polycrystalline Silicon Point Contact Transistors

“…However, the CB oscillation can usually be observed only at temperatures below 77K as the tunnel barriers are not high enough to confine electrons at high temperatures. A surface roughness induced MTJ has also been reported for a very narrow MOS channel [14]. The CB oscillation was observed at room temperature for this structure.…”