本研究探討當羅丹明6G (R6G) 這種高螢光染料附著於銅箔上時，其表面增強拉曼散射的效果。藉由原子力顯微鏡分析與拉曼量測，我們可以推得表面粗糙度與石墨烯，這兩個因素對表面增強拉曼散射個別的增強效果。表面增強拉曼散射是一種偵測低濃度分子的高靈敏度技術，由於表面粗糙度與基材表面的塗層材料都會導致區域性表面電漿共振，使得拉曼訊號增強，我們已經知道這兩個因素都會影響表面增強拉曼散射的效果。為了確認表面粗糙度與塗層材料這兩個因素個別對拉曼訊號的增強所造成的影響，我們藉由不同的化學氣相沉積製程，準備了三種不同的樣品，分別是沒經過退火處理的銅箔、有經過退火但表面沒有合成石墨烯的銅箔，以及表面有合成石墨烯的銅箔。這三塊銅箔的表面粗糙度經過原子力顯微鏡的測量，用方均根值來表示分別為1.65、7.49與1.81奈米。除此之外，我們也以拉曼光譜測量出，每塊銅箔所能量到R6G拉曼訊號的最小R6G濃度，分別是1 × 10⁻³、1 × 10⁻⁴與1 × 10⁻⁶ M，我們稱之為臨界濃度。綜合原子力顯微鏡與拉曼量測的結果，我們可以得到結論：表面粗糙度與石墨烯，對拉曼訊號的偵測分別有10與1000倍的增強效果。

In this research, we have studied the effect of surface-enhanced Raman scattering (SERS) of Rhodamine 6G (R6G), a highly fluorescent dye, adsorbed on copper foils. The impacts of surface roughness and graphene on SERS have been decoupled by utilizing atomic force microscopy (AFM) analysis and Raman measurement. SERS is a high sensitivity technique for the detection of low concentration molecules, and it is well known that surface roughness and coated material may benefit SERS effect since they both can result in the localized surface plasmon resonances (LSPRs) and thus an enhancement in Raman signal. To ensure and decouple the enhancement in Raman signal caused by surface roughness and graphene, respectively, we prepared three samples, a bare copper foil without annealing, a foil experienced thermal treatment without growing graphene, and a foil with graphene coated on it by using different recipes for chemical vapor deposition (CVD) process. The surface roughness of three copper foils was measured by AFM in root mean square (RMS) value as 1.65, 7.49, and 1.81 nm, respectively. In addition, the lowest concentration of R6G to observe a R6G Raman signal (a.k.a. the critical concentration) of each copper foil was measured to be 1 × 10⁻³, 1 × 10⁻⁴ and 1 × 10⁻⁶ M, respectively. Combined with the results of AFM and Raman, we can conclude that the sensitivity of R6G Raman signal is enhanced due to the roughness and graphene by a factor of 10 and 10³, respectively.

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