Synthesis and electrical properties of cyano-substituted oligothiophenes towards n-type organic semiconductors

A series of alpha,omega-cyanooligothiophenes with three, four, five, six an d seven beta,beta'-substituted terthiophenes have been synthesized using th e palladium-catalyzed coupling reaction via organotin or organozinc interme diates. Schottky diode structures with metal/CN-6T-CN/metal using cyano end -capped sexithiophene and various metals were fabricated by vapour depositi on. Electron injection and rectification ratio strongly depend on the metal contact which is compatible with the electron affinity materials. (C) 1999 Elsevier Science B.V. All rights reserved.