Industrial Grade, Bending‐Insensitive, Transparent Nanoforce Touch Sensor via Enhanced Percolation Effect in a Hierarchical Nanocomposite Film

Abstract

Force touch sensors have received a great deal of attention for various applications owing to their versatile ability to detect touch and pressure. To demonstrate high‐performance force touch sensors, numerous studies have been performed, focusing on high sensitivity, transparency, and mechanical durability against bending. However, it is still challenging to apply force touch sensors in flexible applications, because their sensing performance is subject to change and degraded by induced mechanical stress and deformation when the device is bent. Here, a high‐performance and transparent nanoforce touch sensor with bending‐insensitivity is reported. This is achieved by developing a thin, flexible, and transparent hierarchical nanocomposite film, which is composed of a nanostructured plastic base, coplanar electrodes, and a dielectric polymer layer with silver nanoparticles. The fabrication process is simple that high manufacturing repeatability, uniformity, and reliability are achieved on a large‐area (8 in.) scale. The fabricated device shows a pressure sensitivity of 0.036 kPa−1 with high transparency (83%) in a pressure range up to 3 kPa. In particular, its thin thickness (45 µm) and the coplanar electrode enable to achieve excellent insensitivity to the bending with a radius of curvature of 4 mm more than 10 000 times.

Multi‐Layered, Hierarchical Fabric‐Based Tactile Sensors with High Sensitivity and Linearity in Ultrawide Pressure Range

“…Tactile sensors are electronic devices capable of quantifying tactile information through physical contact and are used for monitoring and control in diverse applications ranging from touch sensors on displays to robots designed to interact with objects . With the recent growth in information technology, there is an increase in the demand for high‐performance tactile sensors for use in next‐generation devices, such as electronic skin, Internet of Things devices, and human–machine interfaces.…”

“…Thus, considerable progress has been made in the development of tactile sensors based on various sensing mechanisms, materials, and designs . Sensing mechanisms of the tactile sensors are mainly classified as resistive, capacitive, piezoelectric, or triboelectric types. Among these types, resistive sensors, which transduce applied pressure into a corresponding change in resistance, have been widely used due to their simple measurement scheme and relatively high reliability .…”

Electric‐Field‐Induced Gradient Ionogels for Highly Sensitive, Broad‐Range‐Response, and Freeze/Heat‐Resistant Ionic Fingers

“…These devices have excellent potential for continuously, noninvasively, and real-time data collection. [10][11][12][13][14][15] Nevertheless, with the increasing demand in fields such as health management, clinical diagnosis, and extreme environmental monitoring, more smart devices with new mechanisms and strategy for developing higher sensitivity, broader-range responses, and freeze/heatresistance novel flexible electronics are urgently desirable. [16][17][18][19][20] Even though significant progress has been made in the past decade in the pressure sensors, it remains challenging to overcome the limitation to achieve high sensitivity and broader-range detection simultaneously.…”

A spiking and adapting tactile sensor for neuromorphic applications

“…During the last years, a tremendous effort was made to develop different concepts regarding touch and tactile sensing. Besides traditional piezoelectric materials as for example PbZr x Ti 1−x O 3 (PZT) 15 or BaTiO 3 16 these concepts range from mechanical fluid based 17 sensors to electrical approaches based on graphene [18][19][20][21] , polymers [22][23][24][25][26] , and field-effect transistors coupled capacitively with nanowires 27,28 . Moreover, the possible application of pressure sensors for smart prosthetics 29 and their capability of connecting them directly to nerve cells were explored 30 .…”