自組裝單分子層（self-assembled monolayer, SAM）因具有厚度極薄、分子結構可設計及可調控界面能階等特性，常被應用於光電元件之界面修飾。本研究利用反射式傅立葉轉換紅外光譜（reflection-absorption Fourier transform infrared spectroscopy, RA-FTIR）分析 Me-4PACz 於氧化銦錫（indium tin oxide, ITO）表面之自組裝單分子層形成情形，並進一步探討其分子鍵結、分子取向及表面穩定性等特性。實驗中使用反射基板，並搭配 p 偏振光提升表面分子振動訊號之感測靈敏度。Me-4PACz 以旋塗方式修飾於 ITO 反射基板表面，並透過乙醇清洗移除未穩定吸附或堆疊於表面之分子。此外，本研究也結合接觸角量測、原子力顯微鏡及表面功函數分析，探討清洗前後樣品之表面潤濕性、表面形貌及界面電性變化。

Self-assembled monolayers (SAMs) are widely used for interface modification in optoelectronic devices because of their ultrathin thickness, designable molecular structures, and ability to tune interfacial energy levels. In this study, reflection-absorption Fourier transform infrared spectroscopy (RA-FTIR) was employed to investigate the formation of a Me-4PACz SAM on an indium tin oxide (ITO) surface and to further examine its molecular bonding, molecular orientation, and surface stability.A reflection substrate was used in conjunction with p-polarized light to enhance the sensitivity toward surface molecular vibrational signals. Me-4PACz was deposited onto the ITO surface by spin coating, followed by ethanol rinsing to remove weakly adsorbed or stacked molecules from the surface. Furthermore, contact angle measurements, atomic force microscopy, and surface work function analysis were performed to investigate changes in surface wettability, surface morphology, and interfacial electrical properties before and after rinsing.

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