石墨烯擁有許多優異的特性，如:極高的電子遷移率、優良的導電性、導熱性，尤其是石墨烯為單層碳原子厚度的二維材料，對於環境的敏感度非常的高，且具備可撓性，這將是接下來穿戴式裝置、可撓式透明導電材料、觸控螢幕所需要的特點，石墨烯擁有極大的發展潛力及應用層面，也是許多研究團隊熱中的研究發展熱門材料。
表面增強拉曼散射(Surface Enhanced Raman Scattering, SERS)是一個高靈敏度的微量分子濃度偵測技術，表面增強拉曼散射基板的材料主要是用金(Au)、銀(Ag)與銅(Cu)，而利用銅(Cu)來製作基板的成本比金(Au)與銀(Ag)還要低，但銅(Cu)的缺點為容易在空氣中被氧化，所以，在本實驗中我們製備出同時具備可撓性、與環境穩定性高、不易氧化、表面有一層碳薄膜覆蓋的奈米結構銅基板，用來作為量測表面增強拉曼散射的基板，我們利用微波電漿化學氣相沉積法(MPCVD)與熱化學氣相沉積法(Thermal CVD)來製備碳薄膜覆蓋的奈米結構銅基板，在高溫製程中通入甲烷氣體，使得在銅的表面成長一層碳薄膜，可保護底下的銅基板不會被氧化，過程中碳薄膜也會成長在銅與二氧化矽之間的交界面，並使得銅上下表面有奈米級的粗糙度，且在製備後容易將銅膜從基板上撕起，銅膜的厚度約只有1000nm，可用來作為可撓式的基板，並利用羅丹明(Rhodamine 6G, R6G)作為量測表面增強拉曼散射的染劑，當我們利用此有碳薄膜覆蓋的奈米級結構、可撓式銅基板，利用濃度約10-5 M的羅丹明(Rhodamine 6G, R6G)稀釋溶液，將可量測出其拉曼增強因子(Enhancement factor)達到104倍以上。

We report roughened Cu thin films encapsulated by graphene, amorphous and hybrid nanocarbon films as effective and durable surface enhance Raman scattering (SERS) substrates. Thermal chemical vapor deposition (CVD) has been applied to synthesize amorphous carbon, graphene and their hybrids at substrate temperatures between 300℃ and 1000℃ on Cu films RF magnetron sputtered on oxidized silicon substrates with or without additional aluminum oxide coatings. The CVD process at elevated temperatures simultaneously encapsulates a Cu film with nanocarbon films and roughens it to enable effective plasmonic coupling on the surface of the micro- and nano-structured Cu film. SERS enhancement factor higher than 104 for 10-5 M rhodamine 6G (R6G) molecules in water has been demonstrated. Both oxidized silicon substrates with and without aluminum oxide coatings exhibit similar SERS effects. Surface morphologies of Cu films after CVD processing at around 600℃ results in the best SERS enhancement. Thicker Cu films up to 1500nm results in better SERS enhancement than thinner ones. Durability of the nanocarbon encapsulated, Cu film based SERS substrates has been demonstrated by heating in the ambient air up to 200℃ and exposure to acidic and basic chemicals. Amorphous carbon encapsulation synthesized above 600℃withstands oxidation in ambient air well but is vulnerable to chemical etching by acidic and basic solutions. Graphene-like nanocarbon encapsulation synthesized at 1000℃ is withstands both oxidation in the ambient air and chemical etching.

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