Tokyo Univ : 38MHz Transistor: Organic Semiconductor / Single Crystal Thin Film

Tokyo Univ : 38MHz Transistor: Organic Semiconductor / Single Crystal Thin Film

The University of Tokyo / AIST / National Institute for Materials Science

Organic semiconductor: single crystal thin film

We have newly developed a 1μm channel length microfabrication method on organic semiconductors / single crystal thin films.

A flexible device is manufactured using “ink and printing process dissolved in organic solvent”.

Research group:

We have developed a printing method that can apply a 10 nm thick / organic semiconductor / single crystal ultra-thin film over a large area.

High quality / organic single crystal thin film realizes “high mobility exceeding 10cm2 / Vs”.

This is an extremely promising method for speeding up organic transistors.

Semiconductor integrated devices: response frequency

The response frequency of a semiconductor integrated device depends on “transistor mobility and its channel length”, which performs logical operations.

Traditional approach:

Conventionally, lithography using photoresist has been widely used as a fine processing technique.

However, many photoresists damage organic semiconductor films.

For organic transistors, it was difficult to achieve both high mobility and short channel by lithography.

This time:

This time, the research group applied a thin fluoropolymer film on an organic semiconductor single crystal thin film.

Newly developed damage free / lithography method for organic semiconductors.

Successful 1μm scale fine processing,
High mobility of 10cm2 / Vs and short channel at the same time,
Double the world record of cutoff frequency,
Achieved the world’s fastest 38MHz.

Organic transistors: rectification

In addition, as a result of examining the rectification of this organic transistor, which converts an AC signal into a DC signal, it was demonstrated that the rectification was not lost even at 100 MHz.

Organic transistors: fields of application

The research group succeeded in developing the world’s first organic transistor operating in the ultrahigh frequency range.

Wireless tag power supply:

With a value higher than the RFID tag communication frequency of 13.56 MHz, the device fabricated this time is at a level that can be sufficiently applied to wireless tag power supply.

FM radio broadcast:

The ultra high frequency band is used as radio waves for FM radio broadcasting and amateur radio.

The response frequency is further increased to produce organic integrated circuits for long-range wireless communication in the ultra-high frequency band.

IoT logistics management:

Mass production is possible with a simple printing process. In the future, low cost wireless tags for IoT logistics management.

It can be used for a wide range of applications, such as wireless power supply systems that supply power from electromagnetic waves.

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http://www.optronics-media.com/news/20200207/62748/

http://www.k.u-tokyo.ac.jp/info/entry/22_entry819/