導電高分子擁有可撓曲、低成本、可溶液製備電子元件等優點，因此被運用於薄膜電機體、發光二極體、太陽能電池等研究領域中。由於分子鏈柔軟的特性，使高分子薄膜在容易呈現無序、或中低的結構，產生許多形貌缺陷，而這些缺陷會降低載子傳導效率與元件效能。因此，本實驗經由調控單分子層之分子平面性及密度，使基板表面傾向產生分子平面交互作用力，在分子作層級控制分子排列取向，以利在垂直元件上的電學表現。首先，越增加單分子層末端環狀分子苯環數，越能誘導高分子呈現π-π堆疊，增加載子遷移率；再者，低密度的單分子層越容易改變末端環狀結構的傾斜角，達到增加分子平面的調控，使高分子傾向面堆疊向上成長，確實觀測到載子遷移率符合理論預期增加，成功展現以單分子層調控分子堆疊取向與傳導效能的可行性。本實驗利用單分子層末端基形狀及密度有成功影響P3HT排列，讓垂直元件的研究邁出第一步。

Conducting polymers have the advantages of flexibility, solution processability, and low cost production for electronic device, so they have been widely studied and applied for the research of organic electronics such as thin film transistors, light emitting diodes, solar cells, etc. Due to the soft molecular chain, polymer films present disordered structures in both microscopic and macroscopic scales, and products defects from molecular to bulk levels. Defects will result in low conduction efficiency of conducting polymers. Such serious drawback comes from complex intermolecular interactions in solution process. Therefore, ordered structures ae essential for high performance organic electronics. We propose that the required controls of ordering conducting polymers are facilitated by the self-assembled monolayers (SAM). We used different planar chemical structures of SAMs to enhance intermolecular interactions, and changed the tilt angle of the planar SAMs by changing their densities. The deposited polymers hence can achieve the regulated molecular plane (favoring face on) to facilitate the vertical transport along the normal direction relative to substrate. Conductive atomic force microscopy (C-AFM) and Polarized Raman Scattering spectroscopy were used to measure the enhanced vertical transport corresponding to their molecular orientations. First, by increasing the number of ring structures at the end-groups of SAMs, the deposited conducting polymers accordingly exhibit the increasing carrier mobility. Furthermore, the low-density SAMs are easier to be tilted at a large angle for the end-groups; therefore, the deposition of conducting polymers on the low-density SAMs of benzene ring and naphthalene ring demonstrated higher carrier mobility. This represents the preliminary success of SAM-oriented polymer stacking.

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