Gold/Polyimide-Based Resistive Strain Sensors

Abstract

This paper presents the fabrication and implementation of novel resistive sensors that were implemented for strain-sensing applications. Some of the critical factors for the development of resistive sensors are addressed in this paper, such as the cost of fabrication, the steps of the fabrication process which make it time-consuming to complete each prototype, and the inability to achieve optimised electrical and mechanical characteristics. The sensors were fabricated via magnetron sputtering of thin-film chromium and gold layer on the thin-film substrates at defined thicknesses. Sticky copper tapes were attached on the two sides of the sensor patches to form the electrodes. The operating principle of the fabricated sensors was based on the change in their responses with respect to the corresponding changes in their relative resistance as a function of the applied strain. The strain-induced characteristics of the patches were studied with different kinds of experiments, such as consecutive bending and pressure application. The sensors with 400 nm thickness of gold layer obtained a sensitivity of 0.0086 Ω/ppm for the pressure ranging between 0 and 400 kPa. The gauge factor of these sensors was between 4.9–6.6 for temperatures ranging between 25 °C and 55 °C. They were also used for tactile sensing to determine their potential as thin-film sensors for industrial applications, like in robotic and pressure-mapping applications. The results were promising in regards to the sensors’ controllable film thickness, easy operation, purity of the films and mechanically sound nature. These sensors can provide a podium to enhance the usage of resistive sensors on a higher scale to develop thin-film sensors for industrial applications.

Piezoresistive Sensing Approaches for Structural Health Monitoring of Polymer Composites—A Review

“…Tao et al [80] demonstrated a metal nanoparticle-based sensor deposited via magnetron sputtering of thin-film gold and chromium (400 nm and 20 nm respectively). In addition to robustness owing to the use of polyimide substrate and easy fabrication mechanism due to the employment of magnetron sputtering technique, the sensor performance parameters such as sensitivity and gauge factor were also reasonable (0.0086 Ω/ppm and 4.4-6.9 respectively).…”

Novel Surfactant-Induced MWCNTs/PDMS-Based Nanocomposites for Tactile Sensing Applications

“…As a replacement, these sensors used organic, inorganic and synthetic polymers to form the substrates. Some of the common polymers used to form the flexible sensors are polydimethylsiloxane (PDMS) [16,17], polyethylene terephthalate (PET) [18,19], polyimide (PI) [20,21] and polyaniline (PI) [22,23]. Nowadays, conductive polymers like poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) [24,25] are also being used to maintain the electrical conductivity and mechanical flexibility of the resultant prototypes.…”

Multi-Walled Carbon Nanotubes-Based Sensors for Strain Sensing Applications

“…While considering the type of polymer to fabricate a flexible sensor, some of the primary attributes that are considered are Young’s modulus, high permeability toward heat and temperature, and ability to integrate with nanomaterials to form composites. A few of the polymers used to fabricate the flexible sensors are polydimethylsiloxane (PDMS) [ 11 , 12 , 13 ], polyethylene terephthalate (PET) [ 14 , 15 , 16 ], polyethylene naphthalate (PEN) [ 17 , 18 , 19 ], polyimide (PI) [ 20 , 21 , 22 ], polyvinyl chloride (PVC) [ 23 , 24 , 25 ], and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) [ 26 , 27 , 28 ]. Each of these materials has individualistic advantages and disadvantages associated with them.…”