基于ZnO纳米线阵列和P3HT的混合光电二极管特性

Properties of a hybrid photodiode based on well-aligned ZnO nanowire array and regioregular P3HT

为了发展低成本、大面积和高性能光电二极管,采用简单的化学浴沉积方法,在氧化铟锡(ITO)玻璃基底上生长良好取向的ZnO纳米线阵列(ZNWA),然后在生长的ZNWA上旋涂规整的聚3-己基噻吩(P3HT)层,形成结构为ITO/ZNWA/P3HT/Ag的光电二极管。系统研究了此光电二极管在暗态和在太阳模拟器的光照下的电流-电压(I-V)特性。实验结果表明,器件在暗态和光照下都表现出良好的二极管特性。暗态下,在偏压±2V处的整流率为3 211,理想因子为1.8、低开启电压为0.5V和反偏饱和电流为1.13×10-7 A。在20mW/cm2光照下,在偏压±2V处的整流率为39.1、开启电压为0.3V。器件中产生了大量的光生载流子,根据器件的能级结构图和光生载流子的输运过程对此光电二极管的光响应机理进行了解释。

In order to develop large-area,low-c ost and high-quality photodiodes,in this pater,well-aligned ZnO nanowire array s （ZNWAs） were grown on indium tin oxide （ITO）-coated glass substrate by a facil e chemical bath deposition method.A photodiode with a structure of ITO/ZNWAs/P3HT/Ag was fabric ated using ZNWAs and regioregular poly（3-hexylthiophene-2,5-diyl） （P3HT）.The current-voltage （I-V） characteristics of the photodiode in dark and under illumination with a solar simulator are investigated in deta i l.The results demonstrate that the device shows good diode characteristics in dark and under illumination.It exhi bits a rectification ratio （RR） of 3211at ±2V and ideality factor of 1.8in dark.Under 20mW/ cm2power illumina tion,an RR of 39.1is achieved at ±2V,a large number of photo-generated carriers are produced in the de vice,and their transportation process is illuminated in terms of energy band diagram.