基于金属电极和有机半导体层的制备工艺对有机薄膜晶体管性能的研究

Effects of Fabrication Process of Metal Electrode and Organic Semi-conductor Layer on Performance of Organic Thin-Film Transistors

基于聚合物绝缘材料和半导体材料,采用溶液法旋涂工艺制作了有机薄膜晶体管(OTFT),通过不同方法制备有机半导体层、栅极和漏极,以提高有机薄膜晶体管的器件性能。结果表明,有机半导体层是否图形化以及不同金属电极的制备工艺对器件的接触电阻影响明显。有机半导体层图形化后,器件的开关比有较大的提升。采用lift-off工艺,先在聚合物绝缘层材料上对光刻胶图形化,然后利用真空蒸镀法将金属电极蒸镀到绝缘层材料上,最后将器件浸泡在70℃的NMP溶液中约30min,接触电阻约为4.8×107Ω;采用湿刻工艺对蒸镀在绝缘层材料上的金属电极进行处理,接触电阻有明显的下降,约为3.6×106Ω。

Based on polymer insulators and semiconductors, organic thin film transistors （Organic Thin-film Transistors） were fabricated using spin coating. To improve the performance of organic thin film transistors, the organic semi-conductor layer, gate and drain were fabricated with different methods. The results show that different preparation processes on the device will have obvious effect on the contact resistance. It will have obvious improvement on the Ion/Ioff ratio after organic semi-conductor layer being patterned. When using lift-off process, it needs to pattern the photoresist firstly on the polymer insulation materials, and then deposit metal electrode onto the insulating layer using the vacuum evaporation. Lastly, the device was put into NMP solution about 30 min under the temperature of 70 ℃ and the contact resistance is obtained as 4.8 × 10^7Ω . Using wet etching process on the metal electrode which was evaporated in the insulating layer material will has obvious effect on the contact resistance, and the contact resistance will be reduced to be about 3.6 × 10^8 Ω. Key words,