Ultra‐Flexible Biodegradable Pressure Sensitive Field Effect Transistors for Hands‐Free Control of Robot Movements

Abstract

Sensitive flexible pressure sensors are needed in applications such as health monitoring, robotics, and wearable systems. Herein, crumpled graphene flakes network (c‐GFN) channel based highly sensitive pressure sensing field effect transistors (PRESSFETs) are presented. The solution‐processed PRESSFET devices are developed on ultrathin (≈3 μm thick) biodegradable graphene oxide–chitosan (GO–CS) substrate. The distinctive crumpled morphology of GFN leads to a bandgap of 800 meV, which allows the device to have clear ON and OFF electronic states and low subthreshold swing. The presented device can work over a dynamic pressure range (0.5–2 kPa), while exhibiting good electrical stability and repeatability during rapid switching. The application of the presented device is demonstrated by attaching them to the temple regions of the face and pressing them with flexure and relaxation of respective temporalis muscles for hands‐free control of the movements of a robotic device. The pressure sensing device turns ON when the facial temporalis muscle is flexed and returns to the OFF state when it is relaxed. Finally, the degradability of the devices is presented to demonstrate their easy disposability and potential for zero electronic waste.

Graphene Transistors for In Vitro Detection of Health Biomarkers

“…Advantages have also been demonstrated in GFET biosensors to monitor human activity and control robotic movement. [ 166,169,170 ] In 2021, Park et al. reported a wearable GFET pressure sensor for breath and heart rate detection fabricated by using vertically aligned, position‐ and size‐controlled arrays of ZnO nanotubes grown on a graphene layer.…”

“…[ 170 ] The device was fixed to the temple area of the face and controlled by the respective temporal muscles. [ 170 ]…”

Printed n- and p-Channel Transistors using Silicon Nanoribbons Enduring Electrical, Thermal, and Mechanical Stress

“… 13 , 17 − 22 Efficient use of various materials also makes printing attractive in terms of lower electronic waste (e-waste) and better environment friendliness. 11 − 13 , 23 − 25 As a result, the printing technologies have been explored for devices such as artificial thermoreceptors, 26 touch sensors, 27 synaptic transistors, 28 energy harvesters, 29 − 31 radio frequency identification (RFID) tags, 32 and interconnects, 33 etc. needed in conformable and interactive electronic systems.…”

“…Printed electronics is rapidly changing the way electronics is manufactured and used. − With resource-efficient and low-cost fabrication of electronics over large areas (larger than the commercially available wafers) and flexible and stretchable substrates, the printed electronics is advancing several applications. ,− Efficient use of various materials also makes printing attractive in terms of lower electronic waste (e-waste) and better environment friendliness. − ,− As a result, the printing technologies have been explored for devices such as artificial thermoreceptors, touch sensors, synaptic transistors, energy harvesters, − radio frequency identification (RFID) tags, and interconnects, etc. needed in conformable and interactive electronic systems. ,, However, the nonavailability of high-performance (i.e., low power, fast speed) processing units has restricted the utility of printed electronics to low-end applications.…”

Recent developments in 2D materials for energy harvesting applications

“…The substantial advances in nanotechnology and manufacturing processes have led to innovations in the materials, device fabrication and printed electronics approaches for improving the performance of electronic devices including energy harvesters [32][33][34][35]. In 2004, graphene was exfoliated from graphite and since then, 2D materials have attracted tremendous attention from the wider scientific community for numerous applications including nanogenerators, electromagnetic shielding, flexible electronics, nanoelectromechanical systems and sensors [36][37][38][39][40][41][42][43][44][45][46][47]. The extensive interest in 2D materials lies in their high surface area, transparency and excellent electronic and mechanical properties [48].…”