| 초록 |
Among many issues, investigation of the high performance n-type OTFT material is an important and challengeable topic because n-type materials, in general have lower mobility and air stability compared to p-type materials. In the work, we have synthesized and characterized new NTCDI derivatives employing aniline(NTCDI-B) and 4-trifluoromethly aniline(NTCDI-MF) as the amine components for the synthesis of NTCDI. Due to the presence of electron withdrawing CF3 unit LUMO level of NTCDI-MF was lowered down to -3.87eV, which is 0.15eV lower than that of NTCDI-B. Due to this LUMO stabilization electron mobility was enhanced and oxidation stability in air was largely improved. Top contact OTFT consisting of an active layer of either NTCDI-B or NTCDI-MF showed typical behavior of n-type OTFT; 0.024~0.046 cm2/Vs and 104~106 in the mobility and on-off ratios respectively. For the NTCDI-MF device, however, there was only 10% reduction in mobility even after exposing the device to air for 40 days. |
