導電高分子擁有柔軟、可撓曲、低成本等優點，因此被廣泛地應用於薄膜電晶體、發光二極體、太陽能等有機電子學領域。但高分子巨觀上雜亂的分子結構會產生許多形貌以及電子結構上的缺陷，導致低載子傳導效率。因此，本研究透過修飾自組裝單分子改變基板的表面性質，並藉由改變單分子層以及高分子間的作用力，控制微觀分子排列行為。透過系統性調整單分子層的密度，微控單分子層與高分子側鏈的互嵌作用，並估量相應的高分子微觀排列有序性。本研究不只成功量測出單分子層表面形貌，更計算出單分子層的空間週期，發現最佳單分子層密度與P3HT側鏈週期高度相關，因此得出微觀分子長程有序排列的條件－高分子和單分子層之間幾何結構必須匹配。
本實驗成功的估量自組裝單分子層的密度，釐清高分子和單分子層之間微觀幾何結構的關係，對高分子排列有序性與相應的基本電子結構研究推進重要的一步。

In this study, we systematically regulate the density of self-assembled monolayers (SAM) to control the stacking conformation of semiconducting polymers on the substrate. In order to properly evaluate the density of monolayer, we increased the chain length of the monolayer to enhance the response of atomic force microscope (AFM). Assisted by the elongated SAM molecules, the morphology and the density of the synthesized monolayers were successfully extracted by AFM. After converting the SAM morphology into a one-dimensional frequency spectrum, the spatial period of the monolayer can be estimated. The best monolayer density was found to be highly-correlated to the period of the P3HT side chain. Therefore, when the geometric correlation of the P3HT and the monolayers matches, it is beneficial to order polymers.

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