Researchers from the Computer, Electrical and Mathematical Science and Engineering Division of the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia have developed a process that can make health wearables even more flexible and adaptable to the human body.
Over four years the research team led by Associate Professor of Electrical Engineering at KAUST, Muhammad Hussain, investigated ways to improve the flexibility of silicon materials while retaining their performance.
“We are trying to integrate all device components–sensors, data management electronics, battery, antenna–into a completely compliant system. However, packaging these discrete modules on to soft substrates is extremely difficult,” said Hussain.
Through their research the team devised a method of printing high-performance, silicon-based computers on soft, sticker-like surfaces capable of fitting into the asymmetric contours of the body, or anywhere for that matter.
The team improved on the process of printing circuit patterns with liquid ink from conductive molecules on to materials such as polymers or cellulose. This allows for high-speed roll-to-roll device assembly with low-cost packaging.
Searching for potential electronic skin applications, the researchers developed a sensor containing narrow strips of aluminium foil that changes its electrical conductivity depending on its bending state.
The team printed their decal electronics using 3D techniques that encapsulated the silicon chips and foils into an adhesive layer-backed polymer film. To ensure maximum flexibility, these decal devices use high-mobility zinc oxide nanotransistors on silicon wafers, all thinned down to microscale dimensions.
This device could enable healthcare professionals to monitor a patient’s activity levels, like breathing patterns, eliminating the need of a bulky wearable or something uncomfortable attached to the patient’s skin.
The device is reusable and can be applied to various projects both within and outside of health monitoring.
“You can place a pressure-sensing decal on a tire to monitor it while driving and then peel it off and place it on your mattress to learn your sleeping patterns,” concluded first author of the findings and a KAUST PhD Graduate, Galo Torres Sevilla.
The team’s study was published in the journal Advanced Material Technologies.