Large-Area Fabrication of High-Performance Flexible and Wearable Pressure Sensors

Abstract

Flexible pressure sensors with high sensitivity, broad working range, and good scalability are highly desired for the next generation of wearable electronic devices. However, manufacturing of such pressure sensors still remains challenging. A large-area compliant and cost-effective process to fabricate high-performance pressure sensors via a combination of mesh-molded periodic microstructures and printed side-by-side electrodes is presented. The sensors exhibit low operating voltage (1 V), high sensitivity (20.9 kPa−1), low detection limit (7.4 Pa), fast response/recovery time (23/18 ms), and excellent reliability (over 10 000 cycles). More importantly, they exhibit ultra-broad working range (7.4–1 000 000 Pa), high tunability, large-scale production feasibility, and significant advantage in format miniaturization and creating sensor arrays with self-defined patterns. The versatility of these devices is demonstrated in various human activity monitoring and spatial pressure mapping as electronic skins. Furthermore, utilizing printing methods, a flexible smart insole with a high level of integration for both foot pressure and temperature mapping is demonstrated. The scalable and cost-effective manufacturing along with the good comprehensive performance of the pressure sensors makes them very attractive for future development of wearable smart devices and human–machine interfaces.