碳六十終端分子自組裝在二氧化矽表面的製備與鑑定

Fabrication and characterization of C60-terminated SAM on SiO2 surface

林靖衛(Ching-Wei Lin)

指導教授 ： 洪偉修

國立臺灣師範大學/理學院/化學系/碩士(2009年)

摘要

分子自組裝技術(SAM)廣泛的應用於科學領域中，現今的有機場效電晶體廣泛的應用了分子自組裝技術，其中包括了絕緣層、功函數的調控以及分子自組裝場效電晶體等等。
在本研究主題中，我們經由少數化學修飾的步驟，成功的製造了高品質並以碳六十為終端的單層分子自組裝。表面的化學組成由X光光電子能譜儀來鑑定。而單層分子的品質，由原子力顯微鏡、接觸角量測、橢圓儀以及X光反射率來確認。
以碳六十為終端的單層分子自組裝由下列的幾個步驟完成：首先，將終端為溴的分子(ω-BHTS)自組裝到矽晶圓表面、將終端溴取代成疊氮以及碳六十稼接到疊氮形成aziridine。選擇十七個亞甲基團(methylene group)是為了能夠與OTS做比較。
最後，我們利用熱蒸鍍法將碳六十蒸鍍到下列製備的表面：乾淨的二氧化矽表面、氧電漿處理的二氧化矽表面、甲基團終端的分子自組裝、疊氮基團終端的分子自組裝以及碳六十基團終端的分子自組裝。經由改變表面的狀態，使得控制表面能變成可能。不同的成長機制，包括Volmer—Weber、Stranski—Krastanov 以及Frank—van-der-Merwe成長，都可分別在這些不同的表面中觀察的到。我們接著提出了碳六十分子在這些不同表面能的表面中，不同成長的機制。

關鍵字

碳六十 ； 富勒烯 ； 分子自組裝 ； 薄膜成長

並列摘要

The self-assembled monolayer (SAM) is a widely used technique in many scientific fields. The state-of-art manufacture of the organic field effect transistor includes large parts of the SAM technique such as insulator, work function tuning, SAMFET, etc. In this work, we successfully fabricated the well-controlled C60-terminated SAM on a SiO2 surface with a few steps of chemical modifications. The characterization of the chemical composition on surface was carried out with X-ray photoelectron spectroscopy (XPS). The structural and physical properties of the SAM monolayer were further examined with atomic force microscopy (AFM), contact angle (CA), ellipsometry, and X-ray reflectivity (XRR).
The synthesis of a C60-terminated SAM on a SiO2 surface was performed with several steps: the attachment of ω-BHTS and the subsequent substitutions of the terminal group (bromide and azide). The physical and chemical behaviors of the C60-terminated SAM were compared with those of the CH3-terminated SAM (octadecyltrichlorosilane, OTS).
Finally, a comparison was investigated for the thermal deposition of the C60 molecule on the surfaces with different adlayers including the as-grown SiO2, plasma-treated SiO2, CH3-terminated SAM, Br-terminated SAM, N3-terminated SAM, and C60-terminated SAM. The growth mechanisms of C60, such as Volmer-Weber, Stranski-Krastanov, and Frank-van-der-Merwe growths, were observed on these surfaces, depending on the terminal group. Accordingly, we concluded that the growth mechanism of C60 deposited on the surface was determined by the surface energy.

並列關鍵字

C60 ； fullerene ； SAM ； film growth

參考文獻

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