Ambipolar quantum dots in undoped silicon fin field-effect transistors

TL;DR

This paper demonstrates the integration of ambipolar quantum dots in silicon fin field-effect transistors using standard fabrication techniques, enabling dual classical and quantum operation modes with potential for quantum computing applications.

Contribution

It introduces a novel method to create ambipolar quantum dots in silicon transistors using nickel silicide, operating in both classical and quantum regimes.

Findings

Successful realization of ambipolar quantum dots in silicon transistors.

Demonstration of classical logic NOT gate at low temperature.

Stable quantum dot operation in Coulomb blockade regime for electrons and holes.

Abstract

We integrate ambipolar quantum dots in silicon fin field-effect transistors using exclusively standard complementary metal-oxide-semiconductor fabrication techniques. We realize ambipolarity by replacing conventional highly-doped source and drain electrodes by a metallic nickel silicide with Fermi level close to the silicon mid-gap position. Such devices operate in a dual mode, either as classical field-effect or single-electron transistor. We implement a classical logic NOT gate at low temperature by tuning two interconnected transistors into opposite polarities. In the quantum regime, we demonstrate stable quantum dot operation in the few charge carrier Coulomb blockade regime for both electrons and holes.