Direct imaging of carrier motion in organic transistors by optical secondharmonic generation
Direct imaging of carrier motion in organic transistors by optical secondharmonic generation
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DOI：
10.1038/nphoton.2007.172
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发表时间：
2007-10-01
期刊：
影响因子：
35
通讯作者：
Iwamoto, Mitsumasa
中科院分区：
文献类型：
--
作者：
Manaka, Takaaki;Lim, Eunju;Iwamoto, Mitsumasa
对有机材料中载流子动态行为的研究兴趣源于一些可能的应用，包括有机薄膜晶体管、有机电致发光器件和有机光电导体。它还能为有机半导体和绝缘体中载流子传输和俘获的建模提供深入了解。在此，我们使用一种先进的二次谐波产生技术来探测和可视化有机材料中真实的载流子运动。这是一种时间分辨的微观光学二次谐波产生技术，能够直接且有选择性地探测有机材料中动态载流子运动。利用该技术并使用并五苯场效应晶体管进行的实验揭示了由并五苯引起的二次谐波产生强度分布的动态变化。由此，根据可视化的载流子运动确定了有机固体中的载流子速度。我们预计这种直接可视化技术将在说明有机和无机材料（包括生物材料和聚合物）中空间电荷场的形成方面得到广泛应用。
Interest in the dynamic behaviour of carriers in organic materials is motivated by possible applications that include organic thin-film transistors, organic electro-luminescent devices and organic photoconductors. It can also provide an insight into the modelling of carrier transport and trapping in organic semiconductors and insulators. Here, we use an advanced second-harmonic generation technique to probe and visualize real carrier motion in organic materials. This is a time-resolved microscopic optical second-harmonic generation technique that allows direct and selective probing of dynamic carrier motion in organic materials. Experiments making use of this technique and using pentacene field-effect transistors have revealed dynamic changes of second-harmonic-generation intensity profiles arising from pentacene. Carrier velocity in organic solids is thus determined from the visualized carrier motion. We anticipate that this direct visualization technique will find wide application in the illustration of space-charge field formation in organic and inorganic materials, including biomaterials and polymers.