Polymer–Fullerene Bulk Heterojunction-Based Strain-Sensitive Flexible Organic Field-Effect Transistor

Abstract

In this work, we have fabricated organic fieldeffect transistor using the blend of poly(3-hexylthiophene) and [6,6]-phenyl C61-butyric acid methylester as active layer. Transistor was fabricated in MESFET-type configuration with top gate and bottom drain/source contacts on flexible PET substrate. Drain and source contacts were made using silver (Ag), whereas gate contact was made by depositing aluminium (Al) on the active layer. Active layer showed ohmictype contact with drain/source electrodes and Schottky-type contact with gate electrode, which was discussed with the help of energy band diagram. Current-Voltage (I-V ) characteristics of the transistor were found similar to p-type mode I-V characteristics of a typical low-voltage ambipolar fieldeffect transistor. Strain sensing properties of the device were investigated by bending it at 0 • and 90 • with respect to the direction of drain-to-source current for different strains of 1, 1.6, and 3.2 %. Significant proportional variation in the drainto-source current was observed due to the bending from both sides; however, sensitivity of the device was found higher when strain was applied at 90 • with respect to drain-to-source current. Sensitivity values were found to be equal to 0.18 and 0.65 μA/ % when a constant bending strain of 3.2 % was applied at 0 • and 90 • with respect to the direction of drainto-source current, respectively.

Flexible and Stretchable Physical Sensor Integrated Platforms for Wearable Human‐Activity Monitoringand Personal Healthcare

“…In addition, strain sensors in human-motion detection need to satisfy the following requirements: high stretchability, fl exibility, high sensitivity, high durability, fast response/recovery speeds, and conformability. [ 122 ] Therefore, various types of fl exible and stretchable strain sensing materials such as P(VDF-TrFE), [ 77,123 ] ZnO NWs, [124][125][126][127][128][129] ZnSnO 3 NWs, [ 130 ] CNTs, [ 31,119,131,132 ] CNT composites, [ 28,133 ] graphene, [ 36,[134][135][136][137][138][139] R-GO, [ 121,[140][141][142] R-GO composites, [ 10,34,143 ] Ag NWs, [ 33 ] polymeric nanofi bers, [ 30 ] carbon black (CB), [ 11,144 ] organic semiconductors, [ 32,145,146 ] metal NPs, [ 122 ] Si NWs, [ 147 ] GaInSn, [ 148 ] and conductive polymers [149][150][151][152]…”

A Review of the Use of Carbon Nanotubes and Graphene-Based Sensors for the Detection of Aflatoxin M1 Compounds in Milk

“…This biocompatibility can be addressed by using specific elements such as carbon-based allotropes. This category includes elements such as carbon nanotubes (CNTs) [ 23 , 24 , 25 ], graphene [ 26 , 27 , 28 ], graphite [ 29 , 30 , 31 ] and fullerenes [ 32 , 33 , 34 ]. Among these elements, CNTs and graphene have been extensively used for a wide range of applications.…”