低電位沉積銅在覆有不同單分子層基材之分析及利用 DPN 技術製作銅奈米結構

Underpotential Deposition Behavior of Copper on Different SAMs Substrates and DPN Generated Copper Nanostructures

王家鑫(Jia-Sin Wang)

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(2009年)

https://doi.org/10.6841/NTUT.2009.00636

摘要

本研究是在覆有一自組裝單分子層 (self-assembled monolayers, SAMs) 的金基材上做循環伏安法分析，探討低電位沉積 (underpotential deposition, UPD) 銅的氧化還原電位，而這些自組裝單分子層是使用不同硫醇類，像是 propanethiol (PT)、1-octadecanethiol (ODT) 及 16-mercaptohexadecanoic acid (MHA)。 甚至更針對基材 (矽晶片鍍金、雲母片鍍金) 的部分做分析，利用金基材的多晶和單晶性不同，了解其低電位沉積銅的氧化還原電位是會有影響。也深入探討在覆有單分子層的金基材上所產生的低電位沉積，是否是從基材的缺陷處開始發生的。基材表面形貌是利用原子力顯微鏡觀察，單晶和多晶的金基材使用X-射線繞射分析來判別。
另一研究是結合沾筆式奈米微影術 (Dip-Pen Nanolithography, DPN) 和無電鍍沉積法所製備出銅奈米金屬陣列。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，之後再浸泡在無電鍍銅溶液裡，經由氧化還原反應後，選擇性的將金屬銅沉積在 MHA 點陣圖上，形成金屬 ─ 分子 ─ 金屬的結構。此外也研究沉積時間對金屬結構成長的影響。經實驗結果顯示，隨著沉積時間越久，顆粒會逐漸增大，而點陣圖中的點與點之間的間隔，會因沉積時間過久而連結在一起。本文使用原子力顯微鏡、掃描式電子顯微鏡和光學顯微鏡觀察其表面形貌，並由能量散佈光譜儀分析其金屬銅成份。

關鍵字

自組裝單分子層 ； 低電位沉積銅 ； 沾筆式奈米微影術 ； 無電鍍銅

並列摘要

The first part of this study discusses the underpotential deposition (UPD) behavior of copper on gold substrates coated with self-assembled monolayers (SAMs) and the cyclic voltammetry was employed to analyze the UPD potential. The SAMs are composed of different types of alkanthiols, such as propanethiol (PT), 1-octadecanethiol (ODT) and 16-mercaptohexadecanoic acid (MHA). Moreover, different substrates (Au/Cr/Si, Au/mica) were used for the studies of the UPD potential of copper. The results reveal that the potential were affected when polycrystalline and single crystal gold substrate were used. In addition to the UPD potential, we also studied the UPD bevavior with defects on the substrate. In the study, we used AFM to observe the substrate surface morphology and XRD to determine the crystallinity of gold substrates.
The second part is the combination of Dip-Pen nanolithography (DPN) and electroless deposition of copper to prepare Cu nanostructures. First, using MHA-coated tip to write molecular patterns on the gold substrate and the substrate was passivated in an ODT solution. After the substrate was immersed in the electroless copper solution, the redox reaction was completed by the selective deposition of copper metal on the MHA patterns, in which formed the metal-moleculer-metal structure. To evamine the effect of deposition time on the nanostructures obtained, the results showed that the dimension of nanostructures gradually increased with the deposition time increased. In this thesis, we used AFM、SEM and OM to observe the surface morphology and EDS to analyze the composition of copper nanostructures.

並列關鍵字

self-assembled monolayers ； underpotential deposition of copper ； dip-pen nanolithography ； electroless deposition

參考文獻

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