Flexible and Stretchable Microwave Electronics: Past, Present, and Future Perspective

Abstract

2000759 (6 of 38) www.advmattechnol.de Figure 4. Flexible microwave transistors. a) Schematic illustration of fabrication process flow of flexible microwave TFTs based on Si nanomembrane. Left, two-step transfer-printing of Si nanomembrane on flexible substrate with assist of PDMS stamp. Right, direct flip-printing Si nanomembrane on flexible substrate. Reproduced with permission. [72] Copyright 2010, Wiley-VCH. b) Flexible microwave Si TFT using direct flip-printing approach in (a). Reproduced under the terms of the Creative Commons Attribution 4.0 International License. [75] Copyright 2016, Springer Nature. c) Flexible microwave Si TFT using two-step approach in (a). Reproduced with permission. [72] Copyright 2010, Wiley-VCH. d) Cross-section SEM image of flexible Si MOSFET made by thinning a 65 nm node SOI wafer. Reproduced with permission. [45] Copyright 2013, American Institute of Physics. e) Optical images of flexible GaAs HBT on cellulose nanofibril (CNF) substrate. Reproduced under the terms of the Creative Commons Attribution 4.0 International License. [90] Copyright 2015, Springer Nature. f) Schematic illustration and normalized on-state conductance (G/G 0), maximum transconductance (g m /g m0) of flexible InAs MOSFET with self-aligned gate. Reproduced with permission. [53] Copyright 2012, American Chemical Society. g) Cross-section schematic illustration and gain curves of flexible InGaAs/InAlAs HEMT as function of frequency under various bending conditions. Reproduced with permission. [91] Copyright 2013, American Institute of Physics. h) Output power density (P OUT), power gain (G P) and power-added efficiency (PAE) of the flexible GaN HEMT on thermal conductive tape with thermal conductivity of 1.6 W m −1 K −1. Reproduced with permission. [92] Copyright 2017, Wiley-VCH. i) Photography of AlGaN/GaN film grown on BN coated sapphire substrate and printed on flexible tape. Reproduced with permission. [19] Copyright 2017, Wiley-VCH. j) Cross-section schematic illustration of bottom gate flexible graphene FET (GFET). Reproduced with permission. [93] Copyright 2013, American Chemical Society. k) Cross-section schematic illustration of top gate flexible GFET with self-aligned gate configuration. Reproduced with permission. [94] Copyright 2014, American Chemical Society. l) High-frequency characteristics of flexible GFET with gate length of 50 nm. Reproduced with permission. [95] Copyright 2018, Wiley-VCH. m) Schematic illustration and gain curves of flexible microwave transistor based on MoS 2 as function of frequency. Reproduced with permission. [96] Copyright 2014, Springer Nature. n) High-frequency characteristics of flexible microwave transistor based on black phosphorus (BP) as function of frequency. Reproduced with permission.

Video Capsule Endoscopy and Ingestible Electronics: Emerging Trends in Sensors, Circuits, Materials, Telemetry, Optics, and Rapid Reading Software

“…The biocompatibility of substrates reduces the health and safety risks associated with long-term capsule retention beyond 24 to 48 hours. Flexible and stretchable components, such as antennae, can be packaged in miniaturized form factors to facilitate the initial swallowing and transit and expanded to larger form factors upon reaching the small bowel or colon [8,147]. On the other hand, sensors and microelectronics are often compressed into mechanically rigid structures to save the real estate within capsules.…”

Green flexible electronics based on starch

“…Nowadays, electronic devices are transforming from solid, durable, single-shape styles to wearable, versatile, high-performance, and multifunctional components, among which the flexible electronics (FEs) have already sprung up and gained extensive attentions [1][2][3][4] . The appealing applications of FEs may at least include personalized mobile devices, healthcare systems, human-machine interfaces, soft robots, electronic skin, artificial intelligence (AI), and Internet of Things (IoT) [5][6][7][8] . To fabricate FEs, the soft, stretchable, foldable substrates are highly desired.…”

Atomic Structure Evaluation of Solution-Processed a-IZO Films and Electrical Behavior of a-IZO TFTs

“…Recently, as the demand for flexible displays has increased and direct printing of display products has been attempted, interest in solution processes has drastically expanded [ 1 , 2 , 3 , 4 ]. In display manufacturing, using the solution process, time and cost can be reduced by more than 60% by direct printing at room temperature instead of using a vacuum deposition process [ 5 ].…”