对以并五苯和酞菁铜为不同有源层的有机薄膜晶体管特性研究

Study of the characteristics of organic thin film transistors based on different active layers of pentacene and CuPc thin films

通过扫描电镜和X射线衍射对SiO2衬底上生长并五苯和酞菁铜薄膜的表面形貌进行表征,并得到在SiO2衬底上生长的并五苯薄膜是以岛状结构生长,其大小约为100 nm,且薄膜有较好的结晶取向,呈多晶态存在.酞菁铜薄膜则没有表现出明显的生长机理,其呈非晶态存在.还对通过掩膜的方法制作得以酞菁铜和并五苯为有源层的顶栅极有机薄膜晶体管的特性进行了研究.有源层的厚度为40 nm,绝缘层SiO2的厚度为250 nm,器件的沟道宽长比(W/L)为20.通过Keithley 2410I-V测量仪对OTFTs器件的电学性质进行表征,其器件的开关电流比(on/off)分别为105和104,阈值电压VTH分别为-20 V和-15 V,器件的场效应载流子迁移率μEF分别为0.0694 cm2/V.s和1.201cm2/V.s.

The surface morphology and crystallization of pentacene and CuPc films deposited on SiO2 substrate are characterized by X- ray diffraction （XRD） and scaning electron microscopy （SEM）. It was observed that the pentacene film has island structure, the sizes of islands were about 100 nm. The pentacene has clearer orientation than CuPc. We also studied organic thin film transistors （OTFI＇s） with different active layers of pentacene and CuPc, fabricated by shadow mask to investigate the characteristics of the device. The active layers pentacene and CuPc have the thickness of 40 nm, the thickness of gate insulator layer SiO2 is 250 nm and the ratio of width to length （W/L） of device channel is 20. We analyzed the property of devices by Keithley 2410 I-V. The results presented here show that OTFTs devices in which pentacene and CuPc are used as active layer exhibited the field-effect mobility （μEF） of 1.201 cm^2/V·s and 0.0694 c m·2/V·s, threshold voltage （ Vth ） of -20 V and - 15 V, and （on/off） current radio of 10^4 and 10^5 , respectively.