Ultra low power flexible electronics for next generation wearable devices

Wearable technologies are having a transformative impact on health and social care. The 2019 Topol review of digital technologies for the NHS highlighted wearables as impacting 80% of current models of care by 2040. The NHS long term plan predicts people effortlessly monitoring their physiology at home, with an aim of creating a programming interface to allow wearable devices to feed directly into clinical workflows. NHS @home is already providing remote monitoring devices to patients to increase the use of at home care, enable 'virtual wards', and to provide more personalised care. However, current wearables have a wide number of limitations. They are commonly made with conventional rigid, or semi-rigid, electronics which do not conform to the body nor stretch and flex with movement of the skin. The parameters monitored focus on aspects such as activity and heart monitoring, and do not consider a wide number of different biomarkers such as sweat and light exposure. There are ongoing questions about the data quality, and the usability of devices, together with data privacy and security considerations.

This PhD is aiming to advance the state of the art in the electronics aspects of next generation wearable devices. This involves a mixed focus. Firstly, on flexible electronics using a hybrid integration approach. In this, conventional microchips are mounted onto a flexible (typically plastic) substrate such that the overall device can bend and flex much more freely compared to current devices. This necessitates studies in to component mounting approaches, together with work to make a complete system on these flexible substrates, including the battery, microprocessor, wireless connectivity and similar. Secondly, on adding instrumentation to allow additional parameters to be measured. We anticipate exploring light exposure, ultra-violet light exposure, and electrochemical based sweat sensing, trading-off the time spent on these different factors depending on the views needs of clinical and non-clinical collaborators and co-designers. The principal research challenge will be in maintaining low power consumption and accuracy when moving this instrumentation to a miniature form factor.