Tunable hybrid silicon single-electron transistor-nanoscale field-effect transistor operating at room temperature

A hybrid silicon single-electron transistor (SET)-field-effect transistor (FET), tunable by gate voltages between single-electron and classical FET operation, at room temperature (RT) is demonstrated. The device uses a side-gated, ∼6 nm wide, heavily doped n⁺ silicon fin. A gate-controlled transition occurs from a depletion mode FET, including characteristic output saturation, to a quantum dot SET with “Coulomb diamond” characteristics above and near the threshold voltage, respectively. Below the threshold voltage, p-FET behavior implies ambipolar operation. Statistics for 180 research devices show a high yield of ∼37% for RT SET-FET operation and mean single-electron addition energy ∼0.3 eV. This yield also demonstrates the probability of single-electron effects in highly scaled doped nanoFETs and the possibility of electrically tunable, RT quantum and classical mode, nanoelectronic circuits.