High‐Transconductance Stretchable Transistors Achieved by Controlled Gold Microcrack Morphology. (3rd July 2019)

• Record Type: Journal Article
• Authors: Matsuhisa, Naoji; Jiang, Ying; Liu, Zhiyuan; Chen, Geng; Wan, Changjin; Kim, Yeongin; Kang, Jiheong; Tran, Helen; Wu, Hung‐Chin; You, Insang; Bao, Zhenan; Chen, Xiaodong
• Is Part Of: Advanced Electronic Materials. Volume 5:Number 8(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-07-03
• Subjects: organic electrochemical transistors -- stretchable conductors -- stretchable electronics; Materials -- Electric properties -- Periodicals; Materials science -- Periodicals; Magnetic materials -- Periodicals; Electronic apparatus and appliances -- Periodicals; 537
• DOI: 10.1002/aelm.201900347
• Languages: English
• ISSNs: 2199-160X

Abstract

Abstract: High‐transconductance stretchable transistors are important for conformable and sensitive sensors for wearables and soft robotics. Remarkably high transconductance, which enables large amplification of signals, has been achieved through the use of organic electrochemical transistors (OECTs). However, the stretchability of such systems has been tempered by the lack of stretchable conductors with high stability in electrolytes, high conductance at high strain (100%), and process compatibility with active layers. Highly stretchable and strain‐resistant Au conductors employed to fabricate intrinsically stretchable OECTs are demonstrated. Notably, the conductors exhibit a sheet resistance of 33.3 Ω Sq. −1 at 120% strain, the lowest reported value to date among stretchable Au thin film conductors. High‐performance stretchable Au is realized by suppressing strain‐induced microcrack propagation through control of the microcracks formed in deposited Au thin films. Then, the highly stretchable Au conductors are utilized to fabricate intrinsically stretchable OECTs with a high transconductance both at 0% strain (0.54 mS) and 140% strain (0.14 mS). Among previously reported systems, these OECTs show the highest transconductance at high strain (>50%). Finally, the high‐performance OECTs are utilized in stretchable synaptic transistors, which are critically important for the development of soft neuromorphic computing systems to provide artificial intelligence for future soft robotics. Abstract : The highest transconductance in fully stretchable transistors is reported, which leads to highly conformable and sensitive wearable sensors. Such performance is enabled by highly stretchable microcrack Au conductors with the lowest sheet resistance at high strain (>50%) among the reported stretchable Au thin‐film conductors. Furthermore, the transistors show synaptic transistor characteristics, which is useful for artificial intelligence in soft robotics.