imec has unveiled what it describes as a first-of-its-kind quantum dot qubit device produced using High Numerical Aperture (High NA) extreme ultraviolet (EUV) lithography, marking a step towards the industrial-scale manufacture of quantum computing hardware.

The announcement, made at ITF World, imec’s annual technology forum, represents the first integrated quantum hardware fabricated using this advanced lithography technique, which is typically associated with cutting-edge semiconductor manufacturing.

Quantum computers promise substantial performance gains over classical systems for certain complex tasks, such as drug discovery and the simulation of physical processes. However, building a practical system requires scaling from experimental devices to millions of interconnected qubits, each capable of reliable and precise operation.

imec’s work focuses on silicon quantum dot spin qubits, a technology considered a viable path towards large-scale quantum processors. These qubits rely on confining individual electrons in nanoscale silicon structures, with the electron’s spin state used to represent quantum information. Because the fabrication process is largely compatible with conventional CMOS chip manufacturing, silicon-based qubits are often viewed as a strong candidate for industrialisation.

“We can leverage decades of semiconductor innovation and reuse the entire ecosystem of silicon scaling, moving quantum devices beyond lab experiments to large-scale, manufacturable systems. This is where silicon-based qubits have a clear advantage,” said Sofie Beyne, project leader and quantum integration engineer at imec.

A key challenge in building such devices is controlling the spacing between gate structures, as smaller gaps can reduce unwanted interference and improve qubit interactions. imec reported that it successfully produced a functioning network of qubits with gaps of approximately 6 nanometres. At this scale, it becomes theoretically possible to integrate millions of qubits onto a single chip.

“High NA EUV enables the precise patterning of silicon quantum dot qubits. As the coupling strength between neighbouring quantum dots increases exponentially with the gap between them, we need to reliably pattern gaps of a few nanometres between the control electrodes of the quantum dots. This is a true engineering feat, thanks to our integration and patterning teams and ASML's outstanding high NA EUV technology,” said Kristiaan De Greve, imec fellow and programme director for quantum computing.

The development builds on earlier demonstrations that showed silicon quantum dot qubits could achieve stable operation and low charge noise using CMOS-compatible processes. By incorporating High NA EUV lithography, imec’s latest work shifts the focus from experimental demonstrations towards reproducible fabrication using standard 300 mm semiconductor manufacturing processes.

High NA EUV lithography is widely expected to play a central role in advancing next-generation logic and memory technologies below the 2 nm node. imec’s demonstration suggests that the same technology may also be critical for the production of scalable quantum computing hardware.

The research highlights the growing convergence between advanced semiconductor manufacturing and emerging quantum technologies, as the industry seeks viable routes to practical, large-scale quantum systems.

By: DocMemory
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