Facile fabrication method for pn -type and ambipolar transport polyphenylenevinylene-based thin-film field-effect transistors by blending C60 fullerene

We have demonstrated the solution-processed p - and n -type transports including ambipolar transport organic thin-film transistors (OTFTs), required for complementary thin-film integrated circuit technology, by a facile method of blending the n -type C60 and the p -type [poly(2-methoxy-5-[2'-ethyl-hexyloxy]- 1,4-phenylene vinylene] (MEH-PPV). The carrier transport of PPV-based thin-film field-effect transistors with various C60 compositions are investigated by using the field-effect gated structure. One of the important findings is that tunable electronic properties of OTFTs are achieved by controlling C60 composition using a simple and an inexpensive spin-cast technology. The mobility increases with increase in the C60 composition in both n - and p -type OTFTs. Temperature measurements on n -type OTFTs revealed that transport follows a thermally activated hopping transport model with small activation energy.