Highly Deformable Optoelectronics Using Liquid Metal

• Published in: 2020 IEEE 33rd International Conference on Micro Electro Mechanical Systems (MEMS) pp. 1230 - 1233
• Main Authors: Kozaki, Takashi, Satoshi, Saito, Otsuki, Yota, Matsuda, Ryosuke, Isoda, Yutaka, Endo, Takuma, Nakamura, Fumika, Araki, Takuto, Furukawa, Taichi, Maruo, Shoji, Watanabe, Masayoshi, Ueno, Kazuhide, Ota, Hiroki
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.01.2020
• Subjects: Ionic liquid; Liquid metal; Liquid-heterojunction
• ISSN: 2160-1968
• DOI: 10.1109/MEMS46641.2020.9056451

The study proposes optoelectronics based on liquid metal and photo-switchable ionic liquid with liquid-liquid heterojunction technology. As a proof of concept, a liquid-state light sensor and an optical memory which is switched on and off by UV and blue light exposures were demonstrated. The ionic liquid named 1-butyl-3-(4-phenylazobenzyl)imidazolium bis(trifluoromethanesulfonyl)amide ([Azo][NTf 2 ]) is used to realize functions as a light sensor or an optical memory. This ionic liquid is photoresponsive and can undergo a reversible isomerization controlled by light irradiation of UV or Blue; this property was used to realize the liquid-state optoelectronics in this study. In addition, a liquid-state heterojunction was taken advantage of in interconnects between sensing ionic liquid and liquid metal. The liquid-state heterojunction in the microchannels was critical to preventing intermixing of the two liquid components, especially, when the completed devices underwent mechanical deformation. These two important technologies, the photo-switchable ionic liquid and the heterojunction, achieved liquid-state optoelectronics based on liquid materials.