초록 |
We developed high-performance stable n-type organic field-effect transistors (OFETs) using indenofluorenediones with different numbers of fluorine substituents (MonoFIF-dione, DiF-IF-dione, and TriF-IF-dione). Top-contact OFETs were fabricated via the vacuum deposition of indenofluorenediones as the semiconducting channel material on polystyrenetreated SiO2/Si substrates. TriF-IF-dione FETs with Au source/ drain contacts exhibited good device performances, with a fieldeffect mobility of 0.16 cm2 /(V s), an on/off current ratio of 106 , and a threshold voltage of 9.2 V. We found that the electrical stability for OFETs based on indenofluorenedione improved with the number of fluorine substituents, which was attributed to higher activation energies for charge trap creation. Moreover, the TriF-IF-dione FETs yielded excellent environmental stability properties, because the LUMO energy levels were relatively low, compared with those of the MonoF-IF-dione FETs. |