C 60 thin-film transistors with low work-function metal electrodes

We report C60 thin-film transistor characteristics of top-contact structure with low work-function source and drain electrodes. The electron mobility of the Mg electrode device is one order of magnitude higher than that of the Ag electrode device. The depth profile obtained by using secondary-ion mass spectroscopy demonstrates that Mg atoms strongly diffuse into C60 film during Mg deposition. These findings indicate that the improved mobility is due to the reduction of the parasitic resistance under source and drain electrodes by the Mg doping effect.