研究了有机薄膜晶体管器件。器件是以热生长的SiO2作为有机薄膜晶体管的栅绝缘层,酞菁铜作为有源层的。实验表明采用一种硅烷耦合剂-十八烷基三氯硅烷(OTS)修饰SiO2可以有效地降低栅绝缘层的表面能从而明显提高了器件的性能。器件的场效应迁移率提高了2.5倍、阈值电压降低了3 V、开关电流比从103增加到104。同时我们采用MoO3修饰铝作为器件的源漏电极,形成MoO3/Al双层电极结构。实验表明在同样的栅极电压下,具有MoO3/Al电极的器件和金电极的器件有着相似的源漏输出电流Ids。结果显示具有OTS/SiO2双绝缘层的及MoO3/Al电极结构的器件能有效改进有机薄膜晶体管的性能。
An organic thin-film transistor(OTFT) device is investigated.Thermal grown SiO2 layer is used as the OTFT gate dielectric;Copper phthalocyanine(CuPc) is used as an active layer.It is found that using silane coupling agents-octadecyltrichlorosilane(OTS) can reduce the surface energy of the SiO2 gate dielectric and significantly improve device performance.This OTS/SiO2 bilayer gate insulator configuration increases the field-effect mobility by 2.5 times,reduces the threshold voltage by 3 V,and improves the on/off ratio from 10^3 to 10^4.We adopte MoO3 to modify Al as drain and source electrodes with double-layer structure at the same time.The device with MoO3/Al electrode has similar Ids compared with the device with Au electrode at same gate voltage.Our results indicate that using double-layer of electrode and double-layer of insulator is an effective way to improve OTFT performance.