Japanese researchers develop method for printing single crystal thin-film transistors

[n2doc]

July 20, 2011 by Bob Yirka

(PhysOrg.com) -- Researchers working out of the National Institute of Advanced Industrial Science and Technology (AIST) in Tsukuba, Japan have developed a means for printing thin film transistors using InkJet technology. The team describes the process in their paper published in Nature.

To get around the problem of self-crystallization, inherent in other InkJet/transistor making processes, which result in spreading effects that make it difficult to print uniformly, the team instead chose to use a two step process, whereby one type of ink is sprayed first onto a substrate and is then followed by another immediately afterwards, directly on top of the first; the two then mix, creating an environment whereby one single crisp and sharp crystal grows and adheres to the material it is printed on.

The first ink applied is a liquid (anhydrous dimethylformamide) that holds a semiconductor but is not soluble. The second is comprised of an organic semiconductor in a solvent. After the first is sprayed onto the substrate, followed by a shot of the second, the two then mix naturally, and then, from a single point in the mixture a tiny crystal begins to grow, and keeps on growing until the entire pool of ink is consumed, resulting in a thin film (30-200nm thick) of C8BTBT affixed to the substrate. After printing a complete pattern with their new process onto a substrate, other components were added to complete the transistor.

Researchers are looking at InkJet sprayed transistor technologies in the hope that it could lead to a whole host of products that are based on bendable substrates, such as flexible displays, solar cells, large sheets of sensors, or true ePaper, and because it would offer a lowered cost of production compared to traditional silicon based products.

more

http://www.physorg.com/news/2011-07-japanese-method-crystal-thin-film-transistors.html

[RC]

1. Wow, wad up and throw away electronics.

Think of the space saved in land fills.

[Fire Walk With Me]

2. You know, I already have enough trouble soldering up the first gen of surface-mount components.

This is just irritating ;)