以沾筆式奈米微影術製備金奈米結構陣列

Facile Methods for Patterning Gold Nanostructure Arrays by Dip-pen Nanolithography

吳頌倫(Song-Lun Wu)

指導教授 ： 張裕煦

國立臺北科技大學/工程學院/資源工程研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00600

摘要

本研究是在覆有一自組裝單分子層 (self-assembled monolayers, SAMs) 的金基材上結合沾筆式奈米微影術 (Dip-Pen Nanolithography, DPN) 和化學吸附沉積製備出金奈米金屬陣列。另外使用物理氣相蒸鍍的方式在分子層上鍍第二層金，再使用濕式蝕刻來形成金奈米金屬陣列。
首先利用 DPN 在金基材寫出含有 MHA 的點陣圖，再將基材浸泡入 ODT 作鈍化 (passivation) 處理，經由酯化反應後，再浸泡入cysteamine溶液裡將末端官能基置換成 -SH，利用硫與金的共價鍵，選擇性的將金屬金沉積在改質過的分子點陣圖上，形成金屬─分子─金屬的結構。此外，直接將金基材浸泡入 含 MHA 的酒精溶液，再依上述相同步驟改質後，使用熱蒸鍍第二層金，再由DPN技術製備分子點陣當作保護層後使用濕式蝕刻將其餘部分蝕刻，同樣製備出奈米金屬陣列。而金屬─分子─金屬的結構之電性質與其奈米金屬陣列對拉曼散射的增強效果，經實驗結果顯示，分子電路的電阻非常高，其點陣之間的狹縫存在對拉曼增強也有一定的幫助。本文使用原子力顯微鏡、掃描式電子顯微鏡和暗場光學顯微鏡觀察其表面形貌，並由傅利葉紅外光譜儀來辦別其MHA改質後的官能基變化，使用導電原子力顯微鏡與拉曼光譜儀分析點陣電性與拉曼增強效果。

關鍵字

自組裝單分子層 ； 沾筆式奈米微影術 ； 奈米金屬陣列 ； 表面增強拉曼散射 ； 分子電路

並列摘要

This research was devoted to synthesize gold nanostructure arrays via chemisorption of gold nanoparticles and wet chemical etching, respectively, on molecular patterns made by dip-pen nanolithography (DPN). In the first part we use DPN to write 11-mercaptoundecanoic acid (MHA) molecular features on Au substrate and subsequently passivation was proceeded by immersion the sample into 1-octadecanethiol solution. The surface functionalization was also carried out by esterification reaction of NHS/EDC and cysteamine in order to form a thiol-terminated surface for adsorption of gold nanoparticles via strong interaction between -SH and Au interface. Furthermore, the nonspecific binding of Au was minimized in the present work.
In the second part we employed another strategy to synthesize gold nanostructure arrays by DPN combined with wet chemical etching process. The second gold thin film was deposited by thermal evaporation on the functionalized SAMs/Au substrate with –SH as the end functional groups. MHA patterns, addressed by DPN, were explored as protection layers on the second gold thin film.
The metal-molecules-metal nanostructures obtained were characterized by atomic force microscope, scanning electron microscope and dark-field optical microscope. The electrical characteristics, current images and the Surface-enhanced Raman Scattering properties these molecular junction arrays are also discussed.

並列關鍵字

Self-Assembled Monolayers ； Dip-pen Nanolithography ； Surface-enhanced Raman Scattering ； Molecular Electronics

參考文獻

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