Researchers have made significant progress in developing stable European industry-scale fabrication value chains for solid-state-based quantum computer development.
The computational performance of quantum computers depends largely on their core hardware element: the qubit. At present, there are various approaches to determine the existence of qubits, however, they still require stable scalable fabrication value chains in order to develop into industrially feasible technologies.
A novel project, Project MATQu seeks to further the European capability in materials and processes and facilitate European industry’s ability to expand its development of solid-state-based quantum computers.
The two Fraunhofer institutes IPMS and IAF are contributing expertise in 300 mm manufacturing and low-temperature measurement technology.
Project MATQu, short for Materials for Quantum Computing, began in June 2021 with the objective of facilitating the development of a pan-European research infrastructure for enhancing computing technologies. This innovative project has rallied world-class European research and technology organisations, industrial fabrication facilities, as well as leading application partners in the field of solid-state qubits—a topic of powerful global competition—to apprehend the dream of a European supply chain for materials and processes.
The project is led by the combined business office of the Fraunhofer Group for Microelectronics and the Research Fab Microelectronics Germany, alongside Fraunhofer IAF.
The aim of the project is to develop a European eco-system to enhance the feasible application of essential components of solid-state qubits—including superconducting Josephson junctions (SJJs)—by advancing materials and processing and characterisation technologies for quantum computing hardware. At present, SJJs are the most mature solid-state platform to realise stable superconducting qubits.
Market ready superconducting qubits
Superconducting qubits are some of the more encouraging elements being considered to realise a large-scale quantum computer. The quick triumph of Josephson junction-based qubits can be credited to design principles based founded on well-founded production processes.
However, their performance is reliant on the quality of the fabrication substrates, the materials employed to form the circuit component and the duplicability of the processes employed in fabrication. A durable and regulated value chain is vital to enhancing these parameters further going forward.
The fundamental aim of the project is to expand and transfer both materials and technologies for superconducting qubits from laboratories to the market. Various project collaborators have vast infrastructures suitable for this objective and will contribute with their expertise in materials, process integration, and research to build robust and reproducible qubits.
Industrial-grade fabrication infrastructures will enable the improvement of process parameters and methodically enhancing the functioning of superconducting qubits.
Reducing the variability of qubits
In order to regulate the variability of qubits, complex techniques are necessary. This therefore adds to the complexity of the architecture of quantum computers in comparison to that of conventional computers. Currently, this quantum variability is one of the fundamental factors restricting the scaling of the quantity of qubits in computers today.
The project intendst to limit the variability of quantum components; researchers will examine the influence on device variability of all material parameters and process steps. To do this, project collaborators will assemble broad expertise with developing process steps and designing experiments that enable the reduction of the impact of specific process parameters on device performance.
“While we do not expect the same integration level as classical computer chips for the next 5 to 10 years, we will certainly take a big step towards variability reduction in superconducting qubits,” said Prof. Rüdiger Quay, project coordinator from Fraunhofer IAF.
From R&D to manufacture
“In the project, we are gaining new insights into the material and process influences for the manufacturing process of superconducting qubits, especially in the area of deposition, patterning and the integration of superconducting films. Through novel fabrication processes and testing at cryogenic temperatures, we want to advance the fabrication of devices for quantum computing on a European scale,” added Dr. Benjamin Lilienthal-Uhlig, head of business unit Next Generation Computing at Fraunhofer IPMS.
“A second focus for us is to work with industry and research partners to provide European SMEs and startups with access to state-of-the-art manufacturing facilities and know-how to significantly increase the maturity of superconducting qubit technology and strengthen the European quantum technology ecosystem,” concluded Lilienthal-Uhlig.