對於膠體奈米粒子的粒徑分布分析，多採用動態光散射技術(Dynamic Light Scattering, DLS)進行，該檢測技術雖然能快速得到奈米粒子的分散資訊，並且操作成本低，但仍具有許多限制如: 樣品濃度不可過高、液體顏色不可過深等，且DLS原理為偵測圓球顆粒做布朗運動時，散射光強度隨時間的波動、再經由函數換算得到粒徑分析結果，無法知道顆粒的實際原貌。因此，為討論奈米銀漿料導入不同添加劑三乙醇胺與2-乙基己胺後對顆粒形貌的影響，本研究利用液態電子顯微鏡(Liquid-Cell TEM)檢測技術，能反映液態樣品真實形貌資訊、具有較高精確度的優勢，並結合Image J軟體影像處理，同時進行奈米銀的粒徑分析，與DLS量測結果做比較。
另外，在升溫過程中，奈米粒子容易受到液滴內外側揮發速率不均的影響，而產生不均勻的流動現象，稱為咖啡環效應(Coffee-ring Effect)，形成液滴外側較厚、內側較薄的形貌；為此，本研究比較了不同溶劑、不同陰乾溫度的條件下，對咖啡環效應的影響，並討論奈米銀的流動機制。
最後，本研究也因應現今5G通訊對於電磁波雜訊屏蔽的需求，討論不同添加劑配方的奈米銀漿料製備為銀薄膜後，其電磁波屏蔽效應(EMI Shielding Effectiveness)的表現，並探討與銀薄膜表面形貌(粗糙度、孔隙率)的關聯性。本研究的成果顯示，添加2-乙基己胺能使實驗室自製的奈米銀在溶劑α-松油醇中具有較佳的分散性與穩定性，並且製備為銀漿料後也能具有較好的電磁波屏蔽效果。

In this study, we apply Liquid-Cell TEM to observe the morphology change of silver nanoparticle after adding two types of alkaline solvent Triethanolamine (TEA) and 2-Ethylhexylamine (2-EHA), in order to compare the PSD result by DLS analysis. And we also prepare our silver nanoparticle ink with two additives into silver thin film by spin coating method, discuss the relationship between EMI shielding effectiveness performance and their surface topography (such as roughness and porosity). We can find that, the adding of 2-EHA could make our self-produce silver nanoparticle with better dispersion and stability in solvent α-terpineol, as well as having higher EMI Shielding performance after prepared into silver thin film.

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