A new low-complexity paradigm for analogue computation and hardware learning

The Fellow and his team are seeking to develop a ground-breaking electronic device named the multimodal transistor. Arising from more than a decade of experience in unconventional device design, it allows for entirely new applications such as hardware learning, analog computation and control, while being energy efficient and easy to fabricate.

News headlines in electronic devices usually hail developments in nanoscale billion-transistor chips, yet there are major opportunities for innovation in display screen technologies, in which the requirement of fabricating circuits at low cost over large areas, and not ultimate miniaturization, is prevalent. Existing fabrication facilities are now partly being repurposed for emerging large area electronic (LAE) applications: microfluidics, lab-on-a chip, ubiquitous sensors or wearable electronics. LAE usually contain large arrays of relatively simple circuits with few transistors, as areal performance variations impede the fabrication of complex circuits. Incremental progress in LAE is constantly achieved through processes and equipment improvements, and by using new materials with superior properties, both with large capital investment.

The Fellow proposes a major step in LAE development, a radical new device design: the multimodal transistor (MMT). The MMT enables new ways of designing electronic circuits for efficient analog operations (amplification, data conversion, analog computation), control and feedback, and ultimately, LAE circuits capable of learning (hardware AI), so far impractical with conventional devices and techniques. Functionality is achieved using energy-efficient circuits of minimal complexity, allowing environmentally friendly fabrication at low cost. By greatly expanding the design possibilities, while being entirely compatible with conventional LAE fabrication, MMT circuits extend the usable lifetime of current manufacturing technologies, maximising the return on investment, and can accelerate the uptake of emerging processes such as 2D semiconductors and spatial atomic layer deposition.
The Fellow's team will leverage our long experience in device design and the complementary capabilities of our international partners to design, fabricate and test devices and circuits using vacuum processing and additive manufacturing in conventional and emergent semiconductor systems, supported by state-of-the-art numerical simulation. The team will use their extensive collaborator networks to seed the development of a new electronic design paradigm.

As this is an enabling technology, its applications span fields from disposable medical diagnostics and crop monitoring to autonomous vehicle control, new forms user interfaces and immersive entertainment environments, with substantial long term economical and public benefits for the UK and the world. The implications of the novel functionality, such as hardware AI and autonomy, will be a constantly considered. Stakeholders will be involved in shaping the research through cross-disciplinary workshops, online engagement and science festival participation. The focus on people will further include: continuing a decade-long tradition of training, mentoring and involving school students in the Fellow's research; supporting a strong start to the careers of young researchers involved through mentoring, independence and due to the ground-breaking nature of the work; and incorporating the findings into Surrey's teaching curriculum to increase our graduates' employability.

The Fellowship will accelerate the Fellow's growth as an international technical and thought leader, while retaining valuable skills, intellectual property and know-how in the UK at a time of global uncertainty. A Fellowship is the optimal funding route, allowing full commitment to advancing this trailblazing design paradigm, within a robust structure and collaborative environment which includes world-leading research facilities and support networks.

The proposed versatile electronic device is an enabling technology with numerous uses. Its introduction will broaden the scope of applications for existing technologies, reducing complexity and improving manufacturability; in the long term it provides a new, disruptive framework for computation using minimal device count and ultra-low-cost fabrication, as a complementary development to emerging beyond-Moore nanoscale digital circuits and quantum computers. Arising from the project will be valuable, broad IP, energy efficient technologies and highly trained scientists and engineers.

In the short and medium term, deploying the device as a replacement for complex electronic circuits made with existing technologies would readily result in lower-cost display screens with superior uniformity and aging characteristics. The recent stagnation in conventional display industry profitability (2.4% CAGR, DSCC report, IMID2019) would be overcome through yield increases and a move to higher resolutions without major changes in processes or materials. The same platform, including emerging flexible screen technology, can produce low-cost, high-value solutions for new applications of wide societal and economic benefit. The multimodal transistor's key attributes circumvent many current limitations and will lead to ubiquitous sensors with in-built processing and decision (e.g. for disposable medical diagnostics, agricultural monitoring, smart packaging, etc., industries which collectively are expected to be worth >$60Bn by 2030 globally). Through superior device behaviour and functionality, this will concurrently broaden the output of existing manufacturing facilities and accelerate new technology and material systems uptake, with important economic implications.

In the long term, the largest value of this unconventional design approach is as a new means of performing efficient computation, decision and learning in hardware, with a minimal number of devices and using low-cost fabrication processes. A large variety of efficient autonomous systems, many entirely unforeseen at present, are likely to stem from this enabling technology, with wide-reaching societal and economic implications and directly applicable to the interests of project partners: from new applications of simulation tools and optimised fabrication processes to novel electronic platforms and areas of scientific endeavour. Consideration is given to the ethical and human aspects from the beginning, involving specialists in these areas as well as diverse stakeholders through collaborators' networks and non-technical interest groups (see Pathways to Impact).

The "People at the Heart of ICT" EPSRC priority is further addressed through the training and career opportunities for the early career researchers and students. Unique technical training through working on a major new concept, and ample opportunity for networking or secondment, create a strong foundation for successful careers. The project's length provides job stability for the postdoctoral researchers, as we transition through considerable worldwide uncertainty. New science will be readily introduced into the undergraduate and MSc curriculum at the host institution, ensuring world-leading multidisciplinary training for future specialists. Children of all ages will be introduced to the prospects of STEM careers by building on the inclusive culture of school and community outreach central to the Fellow's activities.

The fellowship will serve as a means of building critical mass in an emerging area, supporting the growth of the Fellow into an international thought leader. Building on past national investment, leveraging EPSRC-supported facilities, and expanding the worldwide recognition of current research activities, the Fellow's growing scientific influence will be utilised to champion UK research excellence, strengthen national science policy and foster new strategic collaboration.