Commercial CMOS Process for Quantum Computing: Quantum Dots and Charge Sensing in a 22 nm Fully Depleted Silicon-on-Insulator Process

TL;DR

This paper demonstrates the formation, control, and charge sensing of quantum dots in a commercial 22 nm CMOS process, advancing scalable quantum computing architectures using industry-standard fabrication techniques.

Contribution

It shows for the first time that quantum dots and charge sensors can be reliably created and operated in a commercial CMOS process, enabling scalable quantum device integration.

Findings

Quantum dots formed in a commercial CMOS process.

Effective charge sensing with single-electron box sensors.

Controlled coupling and detuning of quantum dots.

Abstract

Confining electrons or holes in quantum dots formed in the channel of industry-standard fully depleted silicon-on-insulator CMOS structures is a promising approach to scalable qubit architectures. In this communication, we present measurement results of a commercial nanostructure fabricated using the GlobalFoundries 22FDX(TM) industrial process. We demonstrate here that quantum dots are formed in the device channel by applying a combination of a back- and gate voltages. We report our results on an effective detuning of the energy levels in the quantum dots by varying the barrier gate voltages in combination with the back-gate voltage. Given the need and importance of scaling to larger numbers of qubits, we demonstrate here the feasibility of single-electron box sensors at the edge of the quantum dot array for effective charge sensing in different operation modes -- sensing charge transitions in a single- and double quantum dots forming the quantum dot array. We also report measurement results demonstrating bias triangle pair formation and precise control over coupled quantum dots with variations in the inter-dot barrier. The reported measurement results demonstrate the ability to control the formation and coupling of multiple quantum dots in a quantum dot array and to sense their charge state via a Single Electron Box sensor in a commercial process for the first time.