Enhanced performance of field-effect transistors based on C60 single crystals with conjugated polyelectrolyte

Contact resistance at the interface between metal electrodes and semiconductors can significantly limit the performance of organic field-effect transistors,leading to a distinct voltage drop at the interface.Here,we demonstrate enhanced performance of n-channel field-effect transistors based on solution-grown C60 single-crystalline ribbons by introducing an interlayer of a conjugated polyelectrolyte（CPE） composed of poly[（9,9-bis（3’-（（N,N-dimethyl）-N-ethylamnionium）-propyl）-2,7-fluorene）-alt-2,7-（9,9-dioctylfluorene）]dibromide（PFN+Br-）.The PFN+Br-interlayer greatly improves the charge injection.Consequently,the electron mobility is promoted up to 5.60 cm2V-1 s-1 and the threshold voltage decreased dramatically with the minimum of4.90 V.