Improving Electrical Properties of Bottom-Gate Poly(3-Hexylthiophene) Thin-Film Transistor Using $\hbox {CF}_{4}$ Plasma Treatment

In this letter, the effect of $\hbox {CF}_{4}$ plasma treatment on poly(3-hexylthiophene)-based organic thin-film transistors has been investigated. It was found that $\hbox {CF}_{4}$ plasma treatment on the source/drain electrode can reduce contact resistance and increase mobility. The $\hbox {CF}_{4}$ plasma treatment can increase the mobility from 0.0021 to 0.0102 $\hbox {cm}^{2}/\hbox {V}\cdot\hbox {s}$ and decrease the contact resistance by about 70%. Moreover, the $\hbox {CF}_{4}$ plasma treatment is compatible with the bottom-gate bottom-contact structure without degrading the $\hbox {SiO}_{2}$ layer.