Angstrom-scale ion-beam engineering of ultrathin buried oxides for quantum and neuro-inspired computing

TL;DR

This paper presents a scalable ion-beam annealing method for precise angstrom-scale control of ultrathin buried oxides, enabling advancements in quantum and neuro-inspired computing with improved device performance.

Contribution

It introduces a novel ion-beam annealing technique for ultrathin oxide engineering with angstrom-scale precision, validated through simulations and experimental demonstrations.

Findings

Achieved Josephson junction tuning with 2-37% resistance variation and 0.86% standard deviation.

Demonstrated frequency control of +-17 MHz in superconducting qubits.

Extended coherence times up to 500 microseconds for quantum devices.

Abstract

Multilayer nanoscale systems incorporating buried ultrathin tunnel oxides, 2D materials, and solid electrolytes are crucial for next-generation logics, memory, quantum and neuro-inspired computing. Still, an ultrathin layer control at angstrom scale is challenging for cutting-edge applications. Here we introduce a scalable approach utilizing focused ion-beam annealing for buried ultrathin oxides engineering with angstrom-scale thickness control. Our molecular dynamics simulations of Ne+ irradiation on Al/a-AlOx/Al structure confirms the pivotal role of ion generated crystal defects. We experimentally demonstrate its performance on Josephson junction tunning in the resistance range of 2 to 37% with a standard deviation of 0.86% across 25x25 mm chip. Moreover, we showcase +-17 MHz frequency control (+-0.172 A tunnel barrier thickness) for superconducting transmon qubits with coherence times up to 500 us, which is promising for useful fault-tolerant quantum computing. This work ensures ultrathin multilayer nanosystems engineering at the ultimate scale by depth-controlled crystal defects generation.