A metal-electrode-free, fully integrated, soft triboelectric sensor array for self-powered tactile sensing

Abstract

The dramatic advances in flexible/wearable electronics have garnered great attention for touch sensors for practical applications in human health monitoring and human-machine interfaces. Self-powered triboelectric tactile sensors with high sensitivity, reduced crosstalk, and simple processing routes are highly desirable. Herein, we introduce a facile and low-cost fabrication approach for a metal-electrode free, fully integrated, flexible, and self-powered triboelectric tactile sensor array with 8-by-8 sensor units. Through the height difference between the sensor units and interconnect electrodes, the crosstalk derived from the electrodes has been successfully suppressed with no additional shielding layers. The tactile sensor array shows a remarkable sensitivity of 0.063VkPa(-1) with a linear range from 5 to 50kPa, which covers a broad range of testing objects. Furthermore, due to the advanced mechanical design, the flexible sensor array exhibits great capability of pressure sensing even under a curved state. The voltage responses from the pattern mapping by finger touching demonstrate the uniformity of the sensor array. Finally, real-time tactile sensing associated with light-emitting diode (LED) array lighting demonstrates the potential application of the sensor array in position tracking, self-powered touch screens, human-machine interfaces and many others. Sensors: Fully integrated, soft sensor array for self-powered tactile sensingA fully integrated soft tactile sensor array (ISTSA) that is self-powered and without metal electrodes has been developed using a low-cost, easily performed fabrication process. A sensor array is a group of sensors used for collecting and processing electromagnetic signals, and arrays of tactile sensors have recently attracted substantial attention with the growth of wearable electronics and application in health monitoring and human-machine interfaces. A team headed by Yunlong Zi at The Chinese University of Hong Kong succeeded in developing an ISTSA with remarkable sensitivity. The ISTSA is so flexible that it exhibits excellent pressure sensing even in a curved state. The authors conducted real-time tactile sensing with LED lighting and finger touching, and they believe their ISTSA has considerable potential for application in such areas as position tracking, self-powered touch screens, and wearable electronics.