(Invited) Multi-Functional Flexible Sensor Sheets

Abstract

Flexible and stretchable electronics are now widely studied for a next class of electric devices replaced from the silicon-based conventional inflexible devices. In particular, multi-functional e-skins can contribute to the applications for wearable healthcare devices and Internet of Things (IoT) concepts. For healthcare application, chemical information such as pH, glucose, sodium ion, and potassium ion levels are very important to monitor as well as physical information including activity, temperature, heartbeat, and electrocardiogram (ECG) signals. Furthermore, simultaneous multiple condition monitoring of physical and chemical information is a next class of wearable devices for convenient and safe human life. To realize the multi-functional flexible sensor system platforms, in this talk, flexible physical and chemical sensor sheets using mainly inorganic nanomaterials will be discussed by proposing low-cost, macroscale, and multi-functional material systems. Especially, human-interactive flexible sensors to detect human motion and health conditions are mainly introduced. After understanding the fundamental properties and mechanism of the flexible sensors such as a strain sensor, a temperature sensor, an ultraviolet sensor, a tactile pressure sensor, and a chemical sensor, integrated device applications with several sensors on a flexible film are demonstrated as proof-of-concepts for multi-functional e-skins. Although a lot of researches and developments are still required for practical application, these studies may help to open a door for the next step of flexible electronics.