表面增強拉曼散射(Surface-enhanced raman scattering, SERS)是一項強力的非破壞性檢測工具，從它第一次被發表至今，隨著表面電漿的研究突破與製程技術的進步，其檢測的效果也越來越好。而如何低成本、快速且大量的製作含有高密度的熱點(hot spots)的SERS基板就成了近年研究該領域的重點。
本研究利用奈米壓印微影術與後續金屬沉積製作金/銀奈米柱陣列(Gold/Silver coated nano-pillar arrays)結構的SERS基板。透過這樣的製程方法，我們將原本使用極紫外光干涉式微影術製作的週期100nm與直徑50 nm的高密度的奈米柱陣列成功且快速的複製出來，後續金屬沉積的方式更是能將圓柱之間的間隙壓縮至20 nm左右。後續透過嚴格耦合波分析法與實際量測，判斷與確認不同形貌與金屬的基板的增益效果與適用的激發光源。
我們製作的SERS基板在使用633 nm雷射當激發光源時，在偵測R6G水溶液時，最小的莫耳濃度能達到10-9 M，且除了基板整體的均勻度以相對標準偏差呈現能小於10%外，不同樣品之間所偵測到的訊號強度也非常接近，再再證明我們的製程除了能完整的製作高密度的結構外，相較於其他昂貴的製程方法，我們能更快速更簡便的達到優良的SERS偵測效果。

In this study, we use nanoimprint lithography (NIL) to fabricate silver coated nano-pillar arrays (NPAs) as surface enhanced Raman scattering (SERS) substrate. Such method makes us to duplicate high density NPAs (with 50 nm diameter and 100 nm period) made by other expensive fabrication method easily. With silver deposition, we can reduce the gap between adjacent pillars to 25 nm to produce stronger hot spots. Changing the height of NPAs, the SERS sensing results show that the Rhodamine 6G with the concentration down to 10-9 M can be detected when the height is 50 nm. Besides of low detection limit, our SERS substrates show good uniformity with RSD down to 8.67%. Compared with conventional fabrication method, our approach can have high throughput and reproducibility simultaneously.

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