The world’s first sterilizable flexible organic transistor A path to the development of implantable medical devices

March 21, 2012

Researchers at the University of Tokyo’s Graduate School of Engineering have created the world’s first sterilizable, flexible organic transistor, opening the door to a whole new field of implantable medical devices.

The excellent mechanical flexibility of organic electronic devices is expected to open up a range of new application opportunities in electronics, such as flexible displays, robotic sensors, and biological and medical electronic applications. However, one of the major remaining issues to be resolved before they can be adopted for widespread use is their instability, especially their thermal instability, because low melting temperatures and large thermal expansion coefficients of organic materials cause thermal degradation.

Professor Takao Someya and his team at the Department of Electrical Engineering and Information Systems have demonstrated the fabrication of flexible thin-film transistors (TFTs) with excellent thermal stability and their viability after biomedical sterilization processes. The organic TFTs comprise a high-mobility organic semiconductor, dinaphtho-[2,3-b:2,3-f]-thieno-[3,2-b]-thiophene, and thin gate dielectrics comprising a 2-nm-thick self-assembled monolayer and a 4-nm-thick aluminum-oxide layer. The TFTs exhibit a mobility of 1.2 cm2/Vs within 2-V operation. The TFT characteristics are stable, even after heating to 150°C for 20 seconds in air, the conditions typically employed for medical sterilization.

Press release (Japanese)


Kazunori Kuribara, He Wang, Naoya Uchiyama, Kenjiro Fukuda, Tomoyuki Yokota, Ute Zschieschang, Cherno Jaye, Daniel Fischer, Hagen Klauk, Tatsuya Yamamoto, Kazuo Takimiya, Masaaki Ikeda, Hirokazu Kuwabara, Tsuyoshi Sekitani, Yueh-Lin Loo, and Takao Someya,
“Organic Transistors with High Thermal Stability for Medical Applications”
Nature Communications (UK) on March 6th, 2012 (GMT) Online Edition: 2012 / 3 / 7(Japan time)
Article link


Graduate School of Engineering

Department of Electrical Engineering and Information Systems

Access Map
Kashiwa Campus
Hongo Campus
Komaba Campus