When manufacturing any kind of electronic device, patterning is required to achieve small features, such as different regions of materials with different functions. The ever-increasing complexity of modern electronics and photonics has led to a plethora of approaches to substrate patterning. For each of these approaches, there are always compromises between the speed of patterning (write speed), the minimum feature size, versatility and cost. The most dominant patterning process in electronics and photonics manufacturing is mask-based photolithography. Here, the chip to be patterned is coated with a light-sensitive material known as a "resist," and light is shone onto the resist through a mask with deliberately placed holes. Light that passes through the holes causes a chemical change in the resist, and thus the pattern is transferred from the mask onto the chip. The disadvantage is that each photolithography mask is only suitable for a one particular type of chip design and cannot be reconfigured for the manufacture of other chip designs, and mask design and fabrication is time-consuming and costly. Alternative patterning techniques, known as direct-write lithography, do enable great flexibility in device design, but at the expense of slow patterning speeds, and often large capital and operating costs. Here, we propose a novel process for photolithography, which we name holographic multi-beam interference lithography (HMBIL). HMBIL promises large area patterning with sub-wavelength resolution as well as fast write speeds, short development times, low costs and a dynamically reconfigurable choice of exposure pattern. Using HMBIL, we will demonstrate patterning of arbitrarily-shaped 100 nm feature sizes over large areas with high throughput (>25 cm^2 device area in under 1 hour), which is currently unachievable with direct-write lithography techniques. As a proof-of-principle, we will demonstrate the capability of HMBIL for manufacturing an example device structure: multispectral filter arrays. These filter arrays, when integrated with an image sensor, will allow the acquisition of light spectra for applications as diverse as medical imaging to remote sensing. HMBIL manufacture of multispectral filter arrays will open up a range of avenues for custom detectors and imaging sensors for security, industrial or medical applications. We envisage this versatile new HMBIL process primarily in two locations in the manufacturing chain: Firstly, as a means of rapid prototyping of nanofabricated designs and secondly, as a means of large scale production of individually customised components. This will revolutionise manufacturing processes across a broad range of application areas including miniaturised optoelectronics, versatile point-of-care diagnostic devices, displays and image sensors, on-chip photonics (waveguides and photonic crystals), plasmonics, nano/micro-electromechanical machines, microfluidics, embedded systems and the internet of things, and many more.

Real-time processing of high-resolution images is essential for many new A.I. technologies. However, currently the computational needs, cost and energy requirements are prohibitive for many mainstream applications, not to mention the lack of portability of the processing systems or latency issues if computing is done via the cloud. New approaches must be adopted to meet these challenging demands. Highly parallel computing is widely agreed as the only viable way to achieve the level of performance needed for real-time imaging. However, the complexity and number of circuit components required to achieve this with traditional semiconductor CMOS approaches impacts the overall system's speed and optical resolution. Thus, there is a need to develop new types of circuit components that are specifically designed for neuromorphic computing. Memristors are two terminal electronic devices that have attracted intense research interest owing to their simple fabrication, low-cost manufacture, low power operation and their capacity for ultra-high density, non-volatile data storage. In recent years, memristor performances have advanced considerably. Very high levels of endurance (120 billion cycles) and retention (>10 years) have been achieved, and ultra-high-density cross-bar arrays have been realized with scalability down to 2 nm. However, it is their ability to emulate the memory and learning properties of biological synapses and their potential to produce a new generation of ultra-high performance artificial intelligent devices that has ignited researchers' interest in these remarkable devices. Many basic neuronal functions have been demonstrated and memristor arrays have been shown to efficiently carry out processing in the analogue domain, removing the computational bottlenecks associated with the large number of vector-matrix operations. This combined with recent improvements in device reliability gives a promising outlook for their future use as the world seeks new technologies to circumvent the end of Moore's law and the problems of traditional von Neumann computing, which has inherent bottlenecks in the way information is processed and transported. Recently there has been a drive towards the development of memristor devices that can be read, written or have their switching characteristics modified by the application of light. The development of these devices, termed Optical Memristors, arises due to several potential benefits. Optical systems are free of sources of electronic noise and capacitive coupling effects, which limit the operating speed of traditional electronic devices. The combination of memristor technology with optical systems offers the additional advantage of high-speed data routing while consuming little power, as well as integration as a building block within future optical computer architectures. In this proposal a new type of computer vision recognition system is proposed based on optical memristors (OM) and cellular nonlinear networks (CNN) that leverages the unique capacity of OM's to detect light and store information while also exploiting CNN's ability to simultaneously process the information in all cells at once. This will enable ultra-fast real-time (in-memory and parallel) computation. The approach outlined contrasts with standard vision recognition systems which are inherently limited by data transfer bottlenecks and the slow, serial processing of information. This research will therefore pave the way to a new generation of ultra-fast, high-resolution vision recognition systems that will impact a wide range of current societal needs (e.g. safer autonomous driving, better security systems) and numerous applications in medicine (e.g. high throughput cell imaging for early cancer diagnostics).

Photonics has moved from a niche industry to being embedded in the majority of deployed systems, spanning sensing, biomedical devices and advanced manufacturing, through communications, ranging from chip-to-chip and wireless access to transcontinental scale, to display technologies, bringing higher resolution, lower energy operation and new ways of human-machine interaction. Its combination with electronics enables the Digital Future. The Government's UK Semiconductor Strategy and UK Wireless Infrastructure Strategy both recognise the need for highly trained people to lead developments in these technology areas, the Semiconductor Strategy referring explicitly to the role of CDTs in filling the current shortage of highly trained researchers. Our proposed CDT has been designed to meet this need. Currently manufactured systems are realised by combining separately developed photonics, electronic and wireless components. This approach is labour intensive and requires many electrical interconnects as well as optical alignment on the micron scale. Devices are optimised separately and then brought together to meet systems specifications. Such an approach, although it has delivered remarkable results, not least the communications systems upon which the internet and our Digital Future depends, limits the benefits that could come from systems-led co-design and the development of technologies for seamless integration of photonics, electronics and wireless. Our proposed CDT aims to provide multi-disciplinary training enabling researchers to create the optimally integrated, energy efficient, systems of the future. To realise such integrated systems requires researchers who have not only deep understanding of their specialist area, but also an excellent understanding across this interdisciplinary area ranging across the fields of photonics, electronics and wireless, hardware and software. We aim to meet this important need by building upon the uniqueness and extent of the Cambridge and UCL research programmes, where activities range across materials for future systems; higher levels of electronic, photonic and wireless integration; the convergence of wireless and optical communication systems; combined quantum and classical communication systems; the application of THz and optical low-latency connections in data centres; techniques for high capacity access networks; the substitution of many conventional illumination products with photonic light sources and extensive application of photonics in medical diagnostics and personalised medicine. Future systems will increasingly rely on more advanced systems integration, and so the CDT supervisor team includes experts in electronic circuits, wireless systems and enabling software. By drawing these complementary activities together it is proposed to develop an advanced training programme to equip the next generation of very high calibre doctoral students with the required technical expertise, RRI, ES, commercial and business skills to enable the > £24 billion annual turnover UK electronics and photonics manufacturing industry to create the optimised, closely integrated systems of the future. The PES CDT will provide a wide range of learning methods for research students, well beyond that conventionally available, so that they can gain the required skills. In addition to conventional lectures and seminars, for example, there will be bespoke experimental coursework activities, educational retreats, reading clubs, road-mapping activities, RRI and ES studies, secondments to companies and other research laboratories and business and entrepreneurship courses. Students trained by the CDT will be equipped to expand the range of applications into which these technologies are deployed in key sectors of the Digital Futures and wider economy, such as communications, industrial manufacturing, consumer electronics, data processing, defence, energy, engineering, security and medicine.

This proposal seeks funding to create a Centre for Doctoral Training (CDT) in Connected Electronic and Photonic Systems (CEPS). Photonics has moved from a niche industry to being embedded in the majority of deployed systems, ranging from sensing, biophotonics and advanced manufacturing, through communications from the chip-to-chip to transcontinental scale, to display technologies, bringing higher resolution, lower power operation and enabling new ways of human-machine interaction. These advances have set the scene for a major change in commercialisation activity where electronics photonics and wireless converge in a wide range of information, sensing, communications, manufacturing and personal healthcare systems. Currently manufactured systems are realised by combining separately developed photonics, electronic and wireless components. This approach is labour intensive and requires many electrical interconnects as well as optical alignment on the micron scale. Devices are optimised separately and then brought together to meet systems specifications. Such an approach, although it has delivered remarkable results, not least the communications systems upon which the internet depends, limits the benefits that could come from systems-led design and the development of technologies for seamless integration of electronic photonics and wireless systems. To realise such connected systems requires researchers who have not only deep understanding of their specialist area, but also an excellent understanding across the fields of electronic photonics and wireless hardware and software. This proposal seeks to meet this important need, building upon the uniqueness and extent of the UCL and Cambridge research, where research activities are already focussing on higher levels of electronic, photonic and wireless integration; the convergence of wireless and optical communication systems; combined quantum and classical communication systems; the application of THz and optical low-latency connections in data centres; techniques for the low-cost roll-out of optical fibre to replace the copper network; the substitution of many conventional lighting products with photonic light sources and extensive application of photonics in medical diagnostics and personalised medicine. Many of these activities will increasingly rely on more advanced systems integration, and so the proposed CDT includes experts in electronic circuits, wireless systems and software. By drawing these complementary activities together, and building upon initial work towards this goal carried out within our previously funded CDT in Integrated Photonic and Electronic Systems, it is proposed to develop an advanced training programme to equip the next generation of very high calibre doctoral students with the required technical expertise, responsible innovation (RI), commercial and business skills to enable the £90 billion annual turnover UK electronics and photonics industry to create the closely integrated systems of the future. The CEPS CDT will provide a wide range of methods for learning for research students, well beyond that conventionally available, so that they can gain the required skills. In addition to conventional lectures and seminars, for example, there will be bespoke experimental coursework activities, reading clubs, roadmapping activities, responsible innovation (RI) studies, secondments to companies and other research laboratories and business planning courses. Connecting electronic and photonic systems is likely to expand the range of applications into which these technologies are deployed in other key sectors of the economy, such as industrial manufacturing, consumer electronics, data processing, defence, energy, engineering, security and medicine. As a result, a key feature of the CDT will be a developed awareness in its student cohorts of the breadth of opportunity available and the confidence that they can make strong impact thereon.

However, access to silicon prototyping facilities remains a challenge in the UK due to the high cost of both equipment and the cleanroom facilities that are required to house the equipment. Furthermore, there is often a disconnect in communication between industry and academia, resulting in some industrial challenges remaining unsolved, and support, training, and networking opportunities for academics to engage with commercialisation activities isn't widespread. The C-PIC host institutions comprising University of Southampton, University of Glasgow and the Science and Technologies Facilities Council (STFC), together with 105 partners at proposal stage, will overcome these challenges by uniting leading UK entrepreneurs and researchers, together with a network of support to streamline the route to commercialisation, translating a wide range of technologies from research labs into industry, underpinned by the C-PIC silicon photonics prototyping foundry. Applications will cover data centre communications; sensing for healthcare, the environment & defence; quantum technologies; artificial intelligence; LiDAR; and more. We will deliver our vision by fulfilling these objectives: Translate a wide range of silicon photonics technologies from research labs into industry, supporting the creation of new companies & jobs, and subsequently social & economic impact. Interconnect the UK silicon photonics ecosystem, acting as the front door to UK expertise, including by launching an online Knowledge Hub. Fund a broad range of Innovation projects supporting industrial-academic collaborations aimed at solving real world industry problems, with the overarching goal of demonstrating high potential solutions in a variety of application areas. Embed equality, diversity, and inclusion best practice into everything we do. Deliver the world's only open source, fully flexible silicon photonics prototyping foundry based on industry-like technology, facilitating straightforward scale-up to commercial viability. Support entrepreneurs in their journey to commercialisation by facilitating networks with venture capitalists, mentors, training, and recruitment. Represent the interests of the community at large with policy makers and the public, becoming an internationally renowned Centre able to secure overseas investment and international partners. Act as a convening body for the field in the UK, becoming a hub of skills, knowledge, and networking opportunities, with regular events aimed at ensuring possibilities for advancing the field and delivering impact are fully exploited. Increase the number of skilled staff working in impact generating roles in the field of silicon photonics via a range of training events and company growth, whilst routinely seeking additional funding to expand training offerings.