Fabrication of Self-assembled Film of Silicon Atomic Thin Wires and Its Applications for Optical Devices

低聚硅烷分子链中的硅原子通过σ-电子与另外两个原子形成原子细线。电子离域为σ-超共轭态，不同于一般有机化合物中的σ-电子。然后，低聚硅烷有望具有罕见的光学和电学性质。σ-超共轭度被认为与主分子链的构象有关。在这项工作中，在衬底表面形成了低聚硅烷的自组装膜。测量了薄膜的光学性能和其他性能，并与溶液和自旋场法制备的薄膜进行了比较。结果表明，自组装膜在紫外/可见光光谱中约330 ~ 350 nm处的吸收峰属于σ-σ^*跃迁，向比溶液相和自旋场膜更长的波长侧移动。通过量子化学计算方法，我们得到了t…的扭扭式构象的HOMO-LUMO能隙大于反式构象的结果。结果表明，固定在衬底表面的自组装膜中的低聚硅烷分子具有延伸-超共轭的直反式构象，而溶液和自旋场膜中的低聚硅烷分子具有扭曲的扭扭式构象，具有有限的-超共轭。结果表明，制备自组装膜是控制低聚硅烷光学和电学性能的有效方法之一。我们获得了制作电子光器件等光学器件的重要信息。进一步形成烷基硫醇分子自组装膜，为链式分子自组装膜的制备提供基础研究，并对其应用的电子器件进行了研究。我们证实了自组装膜可以作为隧道屏障膜。我们在室温下观察了表面有自组装膜的金纳米粒子的量子导电现象。少

The Si atoms in oligosilane molecular chain bond with two another atoms by σ-electrons like an atomic thin wire. The electrons delocalize in the state of σ-hyper-conjugation and differ from the σ-electron in usual organic compounds. Then, the oligosilane is expected to have rare optical and electrical properties. The degree of σ-hyper-conjugation is considered to depend on conformation of the main molecular chain. In this work, the self-assembled film of oligosilane was formed on the surface of the substrate. The optical and other properties of the film were measured and compared with those of solution and thin film made by the spin court method. As a result, the self-assembled film was confirmed to have the absorption peak assigned to σ-σ^* transition about 330-350 nm in UV/visible light spectrum shifting to the longer wave-length side than solution phase and the spin court film. By the quantum chemistry calculation method, we obtained the result that the HOMO-LUMO energy gap of the t … More wisted gauche-conformer has larger than trans-conformer. As the result, oligosilane molecules in the self-assembled film fixed to the surface of the substrate have the straight trans-conformer with extending a -hyper-conjugation, while oligosilane molecules in the solution and the spin court film have the twisted gauche-conformer with limited a -hyper-conjugation. The result suggests that the preparation of self-assembled film is one of effective methods to control of optical and the electrical properties of oligosilane. We obtained significant information for fabricating optical devices like as EL device. The self-assembled film of the alkylthiol molecules was formed further as a basic research for the fabrication of self-assembled film of chain molecules, and the electronic device as its application was researched. We confirmed that the self-assembled film could work as a tunnel barrier film. We observed quantum electric conduction phenomenon at room temperature in the gold nano-particles with self-assembled film on those surfaces. Less