Low temperature, solution-processed ambipolar field-effect transistors based on polymer/self-assembled monolayer modified InO_x hybrid structures for balanced hole and electron mobilities exceeding 1 cm~2 V~(-1) s~(-1)

摘要

Ambipolar field-effect transistors (FETs) based on solution-processed organic-inorganic bilayer structures were investigated. An amorphous indium oxide (InO_x) film, as the n-type semiconducting layer, was prepared with an environmentally friendly method and annealed at a low temperature; and a low band-gap (LBG) donor-acceptor (D-A) conjugated polymer, FBT-Th4(l,4), was spin-coated on the InO_x film as the p-type semiconducting layer. To improve the p-type mobility, a self-assembled monolayer (SAM) of octadecyl-phosphonic acid was introduced to modify the surface of InO_x. The ambipolar FETs showed high and well-balanced hole and electron mobilities of 1.1 and 1.5 cm~2 V~(-1) s~(-1), respectively. Furthermore we found that ambipolar FETs could be integrated into functional complementary metal oxide semiconductor (CMOS)-like inverters.