研究了不同界面修饰层对酞菁氧钒(VOPc)薄膜晶体管性能的影响.通过AFM图谱分析不同界面修饰层上VOPc薄膜的生长行为,通过半导体参数测试仪测试分析不同界面上器件的电学特性.实验结果表明,十八烷基三氯硅烷(OTS-18)修饰后生长的VOPc薄膜,比正辛基三氯硅烷(OTS-8)和苯基三氯硅烷(PTS)修饰后的薄膜晶体尺寸更大、质量更优;基于OTS-18修饰的底栅顶接触型VOPc有机薄膜晶体管,在4种结构器件中具有最高的场效应迁移率(051 cm2/V·s),相对于未修饰的器件迁移率提高了近40倍.较长的烷基链能够有效地隔绝VOPc分子和二氧化硅之间的相互作用,利于形成大晶粒尺寸、少缺陷的优质薄膜,获得高迁移率的TFT器件.绝缘层表面自组装单分子层的厚度对其上薄膜的生长行为和相应器件的性能影响极为明显,这一结论对有机半导体薄膜生长和器件制备具有指导意义.

The performance of vanadyl phthalocyanine (VOPc) thin film transistor with different modified surfaces is studied.The surface morphology of VOPc films on different modified surfaces were observed through atomic force microscopy (AFM) maps,and the electrical properties of VOPc OTFT were also observed through semiconductor parameter test instrument.The experimental results reveal that the VOPc film on octadecyltrichlorosilane(OTS-18) modified substrate has much larger crystal size and better film than those on octyltrichlorosilane(OTS-8) and phenyltrichlorosilane(PTS).The VOPc TFT with bottom-gate top-contact type on OTS-18 treated substrate has the highest mobility (052 cm2/V·s) in the four devices,which is 40 times relative to that on non modified.The interaction force between VOPc and SiO2 can be effectively isolated by the length of alkyl chain,conducive to the formation of large grain size and less film quality defects,the high mobility of TFT device can be achieved.The thickness of the self-assembled monolayer on the insulating layer can significantly affect the growth of VOPc films and the performance of device.This conclusion could be supplied as experiment and theory foundations for the fabrication of high-performance TFT and the growth of organic semiconductor thin film.