Piezo-resistive pressure sensor based on CVD-grown ZnO nanowires on Polyethylene Tetrathalate substrate

TL;DR

This paper presents a flexible piezo-resistive pressure sensor using CVD-grown ZnO nanowires on PET substrate, demonstrating enhanced sensitivity and simpler fabrication for wearable applications.

Contribution

The study introduces a novel flexible sensor with improved sensitivity due to high-quality CVD-grown ZnO nanowires and a simplified fabrication process.

Findings

Sensor resistance changed from 100Ω to 2.4kΩ upon bending.

Tenfold improvement in sensitivity compared to previous reports.

Fewer defects in CVD-grown nanowires enhanced device performance.

Abstract

Recent developments in the domain of electronic materials and devices have attracted the interest of researchers toward flexible and printable electronic components like organic transistors, printable electrodes and sensors. Zinc Oxide (ZnO) nanowires (NWs) possess a number of excellent properties like high mobility, large exciton binding energy and the direct-band gap in addition to large piezoelectric coefficients. Here, we report on flexible piezo-resistive sensor based on Indium tin oxide (ITO)-coated Polyethylene tetrathalate (PET) substrate. The device shows sensitivity in terms of change in resistance from 100 {\Omega} to 2.4 K{\Omega} at an applied potential of 5V upon bending from flat to 95 degrees. The 1-D nanowire flexible device in its flat state shows saturated output current. We observed ten folds enhanced variation as compared to previous reports. Improved sensitivity was observed in our experiments due to fewer defects in CVD-grown NWs as compared to others where hydrothermally grown nanowires were used. The methodology of device fabrication reported here requires less time and enables efficient devices for the realization of flexible and wearable technology.