基于NPB的垂直构型有机发光晶体管的光电特性研究

通过将有机空穴阻挡材料BCP薄层插入垂直构型有机发光晶体管器件ITO/NPB（40nm）/Al（30nm）/NPB（20nm）/Alq₃（55nm）/Al中的不同位置对器件光电特性的影响来研究器件漏电流较大的原因以及器件中具体的载流子过程.充分证明了栅极注入的空穴对沟道中的电流有贡献.进而通过用LiF薄层修饰漏极来增强电子的注入并减小漏电流，得到了相对稳定的发光晶体管器件，其发光强度有很大提高并可很好地由栅极电压来进行调控.更换发光材料层容易得到不同颜色的发光晶体管. 关键词： 垂直构型有机发光晶体管（VOLET） 静电感应晶体管（SIT） N')" href="#">NPB （N N′-diphenyl-N')" href="#">N′-diphenyl-N N′-bis（1-naphtyl）-1')" href="#">N′-bis（1-naphtyl）-1 1′-biphenyl-4

Optoelectronic characteristics of NPB-based vertical organic light-emitting transistors

Vertical light-emitting transistor is a kind of optoelectronic devices combining characteristics of light-emitting and the “on/off” function of transistor, and its channel length can be reduced to nanometers to make it operate at low voltages and high speeds. Holes and electrons injected from source and drain electrodes form excitons in the emissive layer and radiate light. The amount of charge carriers can be controlled by the gate voltage, consequently to control the intensity of light emission. In this paper, by inserting a thin hole-transporting BCP layer at different locations in the device ITO/NPB（40nm）/Al（30nm）/NPB（20nm）/Alq₃（55nm）/Al, we explored the reasons of large drain current and the detailed carriers processes in the device by studying the variation of their optoelectronic characteristics. Our experimental data confirmed that holes injected from central Al gate contribute to the current in the channel. Further, LiF thin film was used as a buffer layer to modify the drain electrode, in this way to improve electron injection and reduce drain current. As a result, relatively stable light-emitting transistors were obtained with significant enhancement in light emission, and the emission intensity can be controlled by the gate voltage. The color of the emission light can easily be tuned by using different luminescent materials.