University of Strathclyde Researchers Advance Manufacturing of Optical Chips

Researchers at the University of Strathclyde have made significant strides in the manufacturing of next-generation optical chips, introducing a novel assembly method for ultra-small, light-controlling devices. This breakthrough could pave the way for scalable production of advanced optical systems vital for quantum technologies, telecommunications, and sensing applications. The study, published in the prestigious journal Nature Communications on July 8, 2025, details the development of photonic crystal cavities (PhCCs)—micron-scale structures designed to trap and manipulate light with high precision.

Until now, the mass production of PhCCs has been hindered by minute variations introduced during the fabrication process. Even nanometer-scale imperfections can drastically alter the optical properties of these devices, making it challenging to create uniform arrays directly on-chip. The Strathclyde team, led by Dr. Sean Bommer, devised a method allowing for the physical removal of individual PhCCs from their silicon wafers and their subsequent placement onto new chips. This process includes real-time optical measurement and sorting of each unit based on its optical characteristics, marking a major leap forward in manufacturing technology.

Dr. Bommer explained, "This is the first system of its kind that allows optical measurement of these devices as they are integrated. Using previous methods, assembling these devices felt like building a Lego set, but where you didn't know the color of any particular brick. Now that we can measure their performance during assembly, it unlocks the potential to make more effective and complex designs." In a single session, the research team successfully transferred and ordered 119 PhCCs by their resonant wavelength, creating bespoke arrays that traditional methods could not achieve.

The integration platform also enabled the researchers to observe how these devices respond dynamically during the printing process, revealing both elastic and plastic mechanical effects over various timescales.

Professor Michael Strain, who holds the Fraunhofer & RAEng Chair in Chipscale Photonics, emphasized the importance of this development. "The ability to rearrange these microscopic devices after they have been fabricated is a crucial step in making use of them as elements in larger scale circuits. We're now working towards assembling a diverse range of semiconductor devices onto a single chip to create complex, high-performance systems for telecoms, quantum applications, sensing, and beyond."

The implications of this research extend beyond academic interest; they may significantly impact industries reliant on advanced optical technologies. Quantum computing, for instance, stands to gain from more efficient and scalable photonic systems. With the ability to create complex, high-performance photonic arrays, researchers and industry leaders alike anticipate a new era of innovation in various fields, including telecommunications and artificial intelligence.

This pioneering work not only highlights the University of Strathclyde's commitment to cutting-edge research but also underscores the growing importance of photonic technologies in the global marketplace. As industries continue to explore the potential of quantum technologies and advanced optical systems, the findings from this research could serve as a cornerstone for future developments in the field.