New type of organic semiconductors for field-effect transistors with carbon-carbon triple bonds

A series of thiophene-phenylene semiconductors containing-C C-bonds were designed and synthesized. Their thermal, optical, electrochemical and FET properties were fully characterized. The crystal structure of 5,5'-bis(phenylethynyl)-2,2'-bithiophene (1c) revealed that the introduction of carbon-carbon triple bonds efficiently eliminated the steric repulsions between adjacent aromatic rings. TGA, UV-vis spectra and electrochemical measurements showed that all compounds had good thermal and environmental stability. FET devices based on these materials exhibited high performance and stability. All the results suggested the introduction of carbon-carbon triple bonds provided an efficient route to high performance organic semiconductors.