自我排列單分子層(Self-Assembled Monolayers；SAMs)之技術已廣泛運用於基礎物理及化學現象的探討及研究。而利用低溫電漿進行有機高分子的表面處理，則可在表面上產生聚合、交錯連結及表面的化學反應，創造出具功能性的表面結構。本研究以N2和Ar作為順流式電漿的激發氣體，對於吸附於Au(111)及Ag(111)上的ODT、DDT SAMs進行不同時間的處理，以探討電漿與SAMs的界面反應中，電漿氣體的選擇、AT分子鏈長及吸附基材的影響效應。

　　在實驗中，原基材及經處理後的試片使用位於同步幅射中心的高解析X光光電子能譜儀(HRXPS)進行表面分析，以決定表面結構的變化情形。結果顯示，隨著電漿處理時間的增加，表面鍵結變化的情形也隨之發生，且無論在Ar或N2的電漿環境下，表面鍵結的變化皆以氧化物為主。後續的分析上，由C-C(~285.0eV)、S-metal(~162.0eV)兩鍵結曲峰配湊的結果求得的衰退速率作為各組試驗中反應速率比較的依據。主要的討論結果可整理如下：當使用相同的電漿氣體，對吸附於同樣基材上不同鏈長的AT分子進行處理時，短鏈的DDT分子的反應速率較ODT快；以相同的電漿氣體，對同樣的AT分子吸附於Au或Ag的試片進行處理時，吸附於Au的AT分子反應速率較吸附於Ag快；而分別以N2與Ar電漿對同一組試片進行處理時，N2電漿的反應速率較快。文中則以上述實驗結果為基礎，對於此系統中電漿與SAMs的界面反應機制作進一步的討論。

　Self-assembled monolayers (SAMs) have been widely applied in field such as fundamental research of physics and chemical phenomenon. Surface modification of organic polymer utilized low-temperature plasma could create functionalized surface by polymerization, crosslink and other chemical reaction. In the study, modification of self-assembled Octadecanethiol (ODT) / Dodecanethiol (DDT) on Au (111) / Ag (111) substrate using low-density nitrogen and argon downstream microwave plasmas with different interval. Chain length of alkanethiolate molecules adsorbed upon a substrate and the applied gaseous plasma are three major factorial bodies that may influence the reaction rate and mechanism at the plasma/SAMs/S-metal interfaces.

　Surface characterization of the pristine and the plasma-treated films was performed using high-resolution x-ray photoelectron spectroscopy at the U5 undulator beamline of the National Synchrotron Radiation Research Center. Obviously, with increasing plasma treatment time, noticeable changes on SAMs are observed by HRXPS, whereas the oxygen species play the dominant role in the boundary reactions that produce oxygen-based functional groups whatever in nitrogen or argon plasma process. Further, the intensity of specific bondings, C-C (285.0eV) and S-metal (162.0eV), of each sample were calculated using curve-fitting data. Comparing with the decay trends of C-C and S-metal bonding, one might display the relation of all factors in this system. The main feature of the experimental results can be summarized as follows. Firstly, on the given substrate, the length of alkyl chain noticeably affects the rate and extent of oxidation and desorption processes, while the DDT film either on Au or on Ag can be vastly removed. Secondly, the thin-film SAMs on Ag are much more resistant to plasma-induced degradation than those on Au. Overall, the minor oxygen species in nitrogen plasma is much reactive than those in argon plasma owing to the difference of energy transferring system for the reactive species.

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