Mobility improvement in C₆₀-based field-effect transistors using LiF/Ag source/drain electrodes

Fullerene (C₆₀)-based organic field-effect transistors (OFETs) were fabricated using lithium fluoride (LiF)/silver (Ag) as source/drain electrodes. Field-effect mobility increased from 2.74 to 5.07 cm² V^-1 s^-1 after modifying single Ag electrodes with the proper thickness of LiF layer. Meanwhile, the contact resistance could be reduced from 25 to 10 kΩ. The performance improvement of the OFETs was attributed to the realignment of the energy band, which could reduce the charge carrier injection barrier at the C₆₀/Ag interface. Moreover, the electronic tunneling enhancement was also analyzed in detail to discuss the effect of the LiF layer.