The World’s First Sterilizable Flexible Organic Transistors

This organic transistor is robust under high temperature medical sterilization processes. The high thermal stability of the gate layer was confirmed by a cooperative structural analysis using a synchrotron radiation beam at Brookhaven National Laboratory’s (BNL) Synchrotron Light Source (NSLS).

The study is reported in BNL News and published online in Nature Communications on 6th March 2012*. This research is carried out as an ERATO Project of JST.

In a serious aging society with a declining birth rate, electronics are increasing their importance in health and medical areas. On this background, the expectation is getting higher on a flexible organic transistor, which is a soft electronic switch.

Manufacturing of a flexible transistor on a bio- compatible polymeric film is not too difficult. For practical implementation, however, high temperature stability and low operating voltages are challenging problems with the best match of its softness and bio-compatibility.

The international research team has succeeded in manufacturing an organic transistor on a polymeric film that has a high thermal stability up to 150°C or higher and the low driving voltage of 2 V with high mobility of 1.2 cm2V−1s−1 at the same time. The new type organic transistor can be sterilized in a standard sterilization process (150°C heat treatment).

The key technology to realize the heat resistant organic transistor with low driving voltage is the development of a new insulating film comprising an ultra-thin (–2 nm) and densely packed layer named self-assembled monolayer (SAM).

Research team seems to expect such applications as long implantable devices and some medical devices like a smart catheter, and thin film medical sensors.