A Review of the Progress of Thin-Film Transistors and Their Technologies for Flexible Electronics

Abstract

Flexible electronics enable various technologies to be integrated into daily life and fuel the quests to develop revolutionary applications, such as artificial skins, intelligent textiles, e-skin patches, and on-skin displays. Mechanical characteristics, including the total thickness and the bending radius, are of paramount importance for physically flexible electronics. However, the limitation regarding semiconductor fabrication challenges the mechanical flexibility of thin-film electronics. Thin-Film Transistors (TFTs) are a key component in thin-film electronics that restrict the flexibility of thin-film systems. Here, we provide a brief overview of the trends of the last three decades in the physical flexibility of various semiconducting technologies, including amorphous-silicon, polycrystalline silicon, oxides, carbon nanotubes, and organics. The study demonstrates the trends of the mechanical properties, including the total thickness and the bending radius, and provides a vision for the future of flexible TFTs.

Novel, flexible, and transparent thin film polyimide aerogels with enhanced thermal insulation and high service temperature

“…The use of PI in electronic industry includes application in flexible printed circuit boards (FPCBs) where heat resistance and flexibility are required, 25 insulation of electric wires, 25 and intermetal dielectric (IMD) layer in integrated circuits (ICs). 26 PI is also typically employed as the major material for fabrication of flexible substrates in flexible electronics for oxide thin-film transistors (TFTs), 27 organic field-effect transistors (OFETs), 28 and amorphous metal oxide semiconductors 29 to name a few. Furthermore, in the majority of flexible electronic devices, in order to introduce functionalities into devices, metal oxide layers are typically integrated.…”

Binary solvent engineering for small-molecular organic semiconductor crystallization

“…In recent years, flexible electronics, which is mainly the application of solution processable organic semiconductors in electronic device fabrication, has attracted considerable research attention. 1–8 Significant progress has been achieved in improving the charge carrier mobilities and air stabilities of organic semiconductors. Various small-molecular solution processed organic semiconductors, such as 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene), 9–11 5,6,11,12-tetraphenyltetracene (rubrene), 12–14 2,7-dioctyl[1]benzothieno[3,2- b ][1]benzothiophene (C 8 -BTBT), 15–17 and 2,7-didodecyl[1]benzothieno [3,2- b ][1]benzothiophene (C 12 -BTBT) 18–21 based thin film transistors have been reported with mobilities close to or even higher than 10 cm 2 V −1 s −1 by various research groups.…”

Flexible Oxide Thin Film Transistors, Memristors, and Their Integration

“…[96,97] In addition, infiltration of humidity through these cracks poses another challenge. [97] One way to circumvent microcrack formation is the use of island TFTs; [19,67] their unique structure enables mechanical flexibility by having an array of individual rigid TFTs on a main flexible substrate, connected with flexible highly conductive links in between them. This technology allows the device itself to not bend intrinsically as much as the connections, preserving the integrity of the device structure and performance.…”