有机功能分子是新型纳光电器件研究热门材料之一，多用金属-分子-金属结方法研究其荷电输运特性。本文从无损制备、微纳尺度及可寻址性等方面，综述了金属-分子-金属结器件研究进展。将制备方法归为软接触法、扫描探针显微镜法、对电极法、交叉线法、角沉积法和纳米孔法等六大类，并分析了不同方法及实验参数对荷电输运特性的影响。总的来说，扫描探针法可用于分子电学特性的快速统计分析，但可寻址性差；纳米孔分子结具有良好的可寻址性，可用于分子输运特性的变温研究，但上电极沉积可导致分子层破坏或界面特性不确定；角度沉积法和软接触法可有效减少电极热沉积对分子层的烧蚀，但器件尺度较大；对电极法可获得纳米级可寻址分子结，若结合模板压印交叉纳米线法制备电极，则在无损分子器件研究及其集成方面有很好的前景。%As promising building blocks for molecular electronics, organic molecules have attracted intense research interest. Metal-molecule-metal junctions are often used as testbeds for studying organic molecules’ charge transport properties. In this article, fabrication methods, nanoscalability and addressability of these junctions are reviewed. Fabrication approaches are classified into soft contact, scanning probe microscopy, against-nanowire, crossed-wire, shadow angle evaporation and nanopore junctions. The effects of preparation method on the junction charge transport properties are systematical y discussed. In general, the scanning tunneling microscopy technique is suitable for fast screening of molecular conductance, but cannot address junction that limits their in-situ temperature-dependent characterizations. The nanopore junction guarantees good control over the device size and the intrinsic contact stability, however, the nature of the electrode-molecule interface is not wel understood. Shadow angle evaporation and soft contact techniques can effectively reduce the possibility of device short circuiting; however, the electrode dimensions limit potential applications. The against-nanowire method provides an easy way to fabricate addressable junctions, and if combined with the crossed-wire procedure may have potential for fabrication and three-dimensional integration of molecular junctions.
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