High Mobility, Low Voltage Operating C60 Based n-type Organic Field Effect Transistors

Full text: We have reported the state-of-the-art C60 based bottom gate-top contact transistors by engineering different organic materials (BCB, Polyethylene and Adenine) / metaloxide (AlOx) bilayer as gate dielectric. The engineering of metal-oxide and organic material passivation bilayer combines the advantages of having a high dielectric metal oxide and a thin passivation layer of polymer or small molecule capped on AlOx layer. The passivation layer helps both smoothing the dielectric surface and suppressing the leakage current while providing good interface properties with the semiconductor layers. This results in OFETs that operate at voltages less than 500 mV. The AlOx layers are readily processible from solution and cured at low temperature, instead of traditionally sputtering or high temperature processing, thus this process is suitable for low-cost organic field effect transistors (OFETs) manufacture. The output characteristics of the OFETs show well saturation behavior while the transfer characteristic display an on/off ratio in excess of 103. The OFET devices have a high field effect mobility which ranges from 2 - 5 cm2/V s for different passivation layers, with low threshold voltages ∼ 0.02 V - 0.05 V. (author)