Organic Thin Film Transistors in Mechanical Sensors

Abstract

The marriage of organic thin‐film transistors (OTFTs) and flexible mechanical sensors has enabled previously restricted applications to become a reality. Counterintuitively, the addition of an OTFT at each sensing element can reduce the overall complexity so that large‐area, low‐noise sensors can be fabricated. The best‐performing instance of this is the active matrix, used in display applications for many of the same reasons, and nearly any type of flexible mechanical sensor can be incorporated into these structures. In this Progress Report, some of the flexible sensor devices that have taken advantage of these mechanical properties are highlighted, examining the advantages that OTFTs offer in the hybrid integration of local amplification and switching. In particular, the current research on resistive pressure sensors, capacitive pressure sensors, resistive or piezoresistive strain sensors, and piezoelectric sensors is identified and enumerated.

Flexible Electronics and Devices as Human–Machine Interfaces for Medical Robotics

“…[108] Achieving a high integration density of sensing arrays is dependent on the fabrication process, materials, and the data acquisition method. [128] Meanwhile, the high integration density of the electronics easily leads to crosstalk and interference of the signals. An attractive approach to address this issue is to have transistors that maintain the sensing unit state integrated around the device to control and amplify the signal, namely the "active matrix".…”

“…[108] Achieving a high integration density of sensing arrays is dependent on the fabrication process, materials, and the data acquisition method. [128] Meanwhile, the high integration density of the electronics easily leads to crosstalk and interference 1 mN [86] 0.078-0.018 kPa [95] 1 mm [96] 15 ms [86] 20 mk [97] Stretchable ≈30% [95] Human skin 0.08 Pa >220 kPa −1 50 µm 9 ms NA Flexible Bai et al [98] NA 0.01 kPa −1 0.1 mm 15 ms NA Flexible Yan et al [99] 1 ug ∼ 1.25 Pa 4.4 kPa −1 5 mm NA NA Flexible Wu et al [100] 0.3 Pa >5000 kPa −1 a) 1000 DPI <1 ms NA Flexible Lee et al [101] <0.5 Pa 192 kPa −1 0.8 cm 10 ms NA Flexible Zang et al [102] NA NA 5 mm NA 20 mk Flexible Yokota et al [103] 7.3 ± 1.2 Pa >1.25 MPa −1 2 mm NA 2410 ppm °C−1 Stretchable ≈800% Hua et al [104] 10 Pa ≈1.78 × 10…”

Systematic Analysis of Self-Assembled Nanodielectric Architecture and Organization Effects on Organic Transistor Switching

“…This opens the door to flexible and even stretchable devices . The applications for these high-throughput-derived products include smart windows, , wearable electronics, , radio frequency identification tags, , and diverse (bio)­sensors. ,− …”

Xylem-Inspired Polyimide/MXene Aerogels with Radial Lamellar Architectures for Highly Sensitive Strain Detection and Efficient Solar Steam Generation

“…Pressure sensors that can convert received forces into electrical signals are widely used in autonomous vehicles, industrial manufacturing automation, artificial intelligence, and healthcare monitoring devices. − According to different working mechanisms, pressure sensors are mainly divided into piezoresistive, piezoelectric, and capacitive-type. , Piezoresistive sensors based on the linear change between force-deformation-resistance have been extensively studied and widely used because of their low cost, great operation stability, and high linear response capability. − Conventional piezoresistive sensors are mostly constructed by metal or inorganic semiconductor materials, which have serious concerns of portability, flexibility, and wearability. , Therefore, flexible sensors involving flexible conducting materials have received extensive attention in the fields of electronic skin and robots due to their good flexibility, wearability, and real-time monitoring ability . Conductive polymer composites with good compressibility are ideal candidates for flexible piezoresistive sensors, − which are usually constructed by direct deposition of conductive materials on insulating matrixes via impregnation and sputtering methods .…”

“…1−4 According to different working mechanisms, pressure sensors are mainly divided into piezoresistive, piezoelectric, and capacitive-type. 5,6 Piezoresistive sensors based on the linear change between forcedeformation-resistance have been extensively studied and widely used because of their low cost, great operation stability, and high linear response capability. 7−9 Conventional piezoresistive sensors are mostly constructed by metal or inorganic semiconductor materials, which have serious concerns of portability, flexibility, and wearability.…”