Large area liquid crystal monodomain field-effect transistors
Large area liquid crystal monodomain field-effect transistors
复制标题
DOI：
10.1021/ja055337l
复制
发表时间：
2006-02-22
影响因子：
15
通讯作者：
Meskers, SCJ
中科院分区：
文献类型：
--
作者：
van Breemen, AJJM;Herwig, PT;Meskers, SCJ
液晶线有机半导体的丁基，己基和脱发衍生物5,5双素bis（5alkyl-2-甲基乙烯基）-2,2'：5'，2'，2double-Prime-terthihiophene合成并与其研究。结构，光学和电气性能。通过优化的热退火方案，可以将己基和脱甲基化合物处理成直径高达150 mm的自组装单构域膜。用X射线衍射法对这些进行了研究，X射线衍射法揭示了与底物平行的薄片具有明显的单晶单斜形形态。在薄片中发现分子以大约50度的倾斜度和聚酰亚胺对齐层的摩擦方向排列。紫外线吸收的测量结果证实了所得的，紧密的左右堆积，该测量结果显示为19，并指示H-聚集。 AFM分析揭示了单域表面粗糙度的自我亲和力。这些化合物在TOF测量中显示了双极电荷传输，孔的迁移率高达0.02 cm（2）/Vs，最大电子迁移率约为0.002 cm（2）/vs。将己基衍生物加工到大面积单构域顶胶质晶体效应晶体管中，它们稳定了几个月，并且显示出高达0.02 cm（2）/Vs的各向异性孔迁移率。与多域底栅晶体管相比，单域的形成允许迁移率增加1个数量级。
Butyl, hexyl, and decyl derivatives of the liquid-crystal line organic semiconductor 5,5 double prime -bis(5alkyl-2-thienylethynyl)-2,2':5',2double prime -terthiophene were synthesized and studied with respect to their structural, optical, and electrical properties. By means of an optimized thermal annealing scheme the hexyl and decyl compounds could be processed into self-assembled monodomain films of up to 150 mm in diameter. These were investigated with X-ray diffractometry, which revealed a clearly single-crystalline monoclinic morphology with lamellae parallel to the substrate. Within the lamellae the molecules were found to arrange with a tilt of about 50 degrees with the rubbing direction of the polyimide alignment layer. The resulting, close side-to-side packing was confirmed by measurements of the UV/vis absorption, which showed a dichroic ratio of 19 and indicated H-aggregation. AFM analyses revealed self-affinity in the surface roughness of the monodomain. The compounds showed bipolar charge transport in TOF measurements, with hole mobilities reaching up to 0.02 cm(2)/Vs and maximum electron mobilities around 0.002 cm(2)/Vs. The hexyl derivative was processed into large-area monodomain top-gate field-effect transistors, which were stable for months and showed anisotropic hole mobilities of up to 0.02 cm(2)/Vs. Compared to multidomain bottom-gate transistors the monodomain formation allowed for a mobility increase by 1 order of magnitude.