Micro-LEDs is a revolutionary form of electronic visual display technology, which is semiconductor-based and utilises very high densities of micron-sized LED pixels. Advanced commercial micro-LED demonstrators now in the public domain include Samsung’s ‘The Wall™’ and Sony’s ‘Crystal LED™’ TVs and virtual and augmented reality headsets being developed by such as Facebook and Microsoft.
The University of Strathclyde’s Institute of Photonics is a recognised international pioneer of this technology, which it has developed over the past 25 years. These devices have proven capabilities in application areas well beyond simple display functionality, including optical wireless communications (OWC) networks [1], quantum key distribution (QKD) [2,3], biophotonics, and quantum-level imaging. The attraction of this technology is underpinned by direct interfacing to CMOS electronics [4], operation at very high (Megahertz) frame rates, and data transmission at gigabits/second [5].
Recent research has focussed on deep ultraviolet (230-280 nm wavelength) LEDs with up to 800 MHz bandwidth [5,6] which are attractive for terrestrial and space-based optical links for both classical and quantum communications. The research is carried out in collaboration with partners at Fraunhofer UK, University of Cambridge, University of Bristol, and University of Edinburgh, and has been supported through the EPSRC national federated telecommunications hubs and funding from Innovate UK and UK Space Agency.
This project will design and fabricate bespoke Micro-LEDs tailored to the specific requirements of free-space QKD and high-speed optical wireless transceiver units. The successful applicant will combine advanced research in photonics with underpinning experience in clean-room based microfabrication. They will learn to design the micro-LED device structures and to fully process them from supplied semiconductor wafers, using a suite of advanced processing tools including mask-based and laser lithography, dry etching, micro-transfer printing, metallization and dielectric deposition. They will thus gain valuable experience in advanced semiconductor processing techniques – skills in high demand in academic research and in industrial R&D. The PhD student, advantageously having a background in physics, materials science or electronic engineering, will have access to state-of-the-art clean-room tools and facilities and extensive optical test and measurement facilities, and engage in collaboration with our partners.
This project is in partnership with Fraunhofer Centre for Applied Photonics (CAP), the UK’s first Fraunhofer centre, part of Fraunhofer UK Research Ltd, which provides professional R&D services to industry. The student will benefit from additional supervision from Fraunhofer CAP staff and exposure to the real-world requirements of commercial applications. We plan for the student to undertake a short placement (~ 1 – 3 months) at Fraunhofer CAP, accessing high-specification test and measurement equipment in their laboratories, and testing the micro-LEDs fabricated in the project for commercially relevant use-cases.