Poly(2,7-carbazole) derivatives as semiconductors for organic thin-film transistors

New poly(2,7-carbazole) derivatives have been synthesized using Yamamoto or Stille coupling reaction. These polymers are highly soluble in common organic solvents and have relatively high molecular weights. Solution-processed organic field-effect transistors using these new polymeric semiconductors were found to exhibit hole mobility up to 2.0 x 10(-3) cm(2) .V(-1)s(-1) with a current on/off ratio of 5 x 10(4) under ambient conditions.