Seminar on wearable electronics

Welcome to a research seminar by Professor Matsuhisa from the University of Tokyo, Japan. 

Host: Prof. Olli Ikkala, Department of Applied Physics

Title of the talk: Skin-conformable sensors and displays by stretchable electronic materials

Abstract: Wearable healthcare devices realize reliable monitoring of physiological signals in the long term, which helps us find or prevent diseases in the early stage. However, current wearable devices, such as watches or rings, have poor skin contact, degrading signal integrity. This is due to the huge mechanical mismatch between rigid wearables and soft human skin.¹

In this presentation, we show skin-like soft sensors and displays formed with stretchable polymeric electronic materials (Figure 1).¹ The devices showed exceptional skin0conformability because they have a low Young’s modulus (<10 MPa) and small total thickness (<10 µm). For example, we developed high-resolution patternable stretchable conducting polymers by doping ionic additives in PEDOT:PSS. This material allowed us to realize skin-conformable transparent touch and strain sensors.² Additionally, we fabricated highly skin-conformable piezoelectric sensors by the conducting polymer and stretchable and piezoelectric polymer. We also fabricated an ultrathin and stretchable electrochromic display, which can be used as an information display for signals obtained by skin-attached sensors.

Biography of Speaker: Naoji Matsuhisa is an Associate Professor at the Research Center for Advanced Science and Technology (RCAST) at the University of Tokyo. His research interest is in stretchable electronic materials and devices for the application in next-generation wearable devices and human-computer interfaces. He received his PhD degree from the University of Tokyo in 2017. Then he worked as a postdoctoral researcher at Nanyang Technological University in Singapore, and Stanford University in the U.S. In 2020, he joined the Department of Electronics and Electrical Engineering at Keio University as an Assistant Professor. In 2022, he became an Associate Professor at the Institute of Industrial Science (IIS) in the University of Tokyo. He has published more than 60 peer-reviewed papers (>10,000 citations). He is the recipient of >10 awards including MIT Technology Review Innovators Under 35 in 2022, and Project Management Institute Future 50 in 2023.

References:

1. Shimura, T.; Sato, S.; Zalar, P.; Matsuhisa, N. Engineering the Comfort-of-wear for next Generation Wearables. Adv. Electron. Mater. 2023, 9, 2200512.
2. Shimura, T.; Sato, S.; Tominaga, T.; Abe, S.; Yamashita, K.; Ashizawa, M.; Kato, T.; Ishikuro, H.; Matsuhisa, N. A High‐resolution, Transparent, and Stretchable Polymer Conductor for Wearable Sensor Arrays. Adv. Mater. Technol. 2023, 8 (12), 202201992.