Researchers Create Faster and Cheaper Organic Transistors

A collaborative study funded by DARPA has led to the development of the world's fastest thin-film organic transistors. This newly developed thin, transparent semiconductor will lay the foundation for cheap, high performance displays in the future.

The joint research led by researchers at the University of Nebraska Lincoln (UNL) and the Stanford University has developed a thin transparent semiconductor, a breakthrough, which operates five times faster than the previous version of the technology.

The development of this fastest organic transistor was led by UNL assistant professor Jinsong Huang and Stanford professor Zhenan Bao. This new technology can deliver high resolution images found in expensive television screen displays.

 The desire to use inexpensive, carbon rich molecules and plastics to develop semiconductors, which give similar results to the expensive technologies based on silicon, has existed for years. Initially, the word 'organic' was limited to compounds that were produced by living organism but gradually this term now includes synthetic substances based on carbons.

To create the thin-film organic transistor, the researchers drop a special solution that contains carbon rich molecules and a complementary plastic on a spinning platter made of glass. Due to the spinning action, a thin coating of the material gets deposited on the platter.

Certain changes were made to this basic process. Initially, they spun the platter faster and then they coated just a tiny portion of the spinning surface equal to the size of a postage stamp. These alterations allowed a denser concentration of the organic molecules to be deposited in a regular alignment. This resulted in enhanced carrier mobility (the rate at which the electrical charges travel)in the transistor. The researchers called this new method, "off-center spin coating." 

Further improvements to this experimental process might lead to the development of inexpensive, high performance electronics built on transparent substrates like glass and flexible plastics, according to the university press release.

According to media sources, the scientists claim their semiconducting material is 90 percent transparent to the naked eye.

The details of this new development are reported in the edition of Nature Communications.