受惠於半導體製程的進步，表面增強拉曼散射(Surface-enhanced Raman scattering, SERS)得以利用圖案化的貴金屬基板產生的電場增益效果來解決普通拉曼散射訊號微弱的問題，成為近年來檢測化學、生物分子最常使用的技術。
本研究利用團鏈共聚物定向自組裝(block copolymer directed self-assembly, BCP-DSA)及金屬轉印技術(metal transfer printing, mTP)製作金屬共振腔結構的SERS基板。透過奈米壓印微影術(nano-imprint lithography)及BCP-DSA的圖案化方法，我們能製作出週期40 nm及線寬15 nm的週期性光柵結構。經金屬轉印及金屬蝕刻，我們得到結構參數一致但基板材質不同的金共振腔及金光柵結構。
我們透過近場模擬及理論計算來探討結構參數對電場增益的影響，我們所製作的共振腔結構在狹縫處所產生的局部電場增益較光柵結構來的強烈。電場增益的效果同時在SERS量測上獲得驗證，共振腔結構所能偵測的最小R6G(Rhodamine 6G)分子濃度為10-7 M，相較於光柵結構有6倍的SERS訊號增益。我們所製作的SERS基板可簡單的經由金屬濺鍍及金屬轉印製程重現，相較於利用電子束微影的製作方法有較低的製作成本及較大的圖案面積，也較膠體溶液自組裝製作的SERS基板有較佳的再現性。

In this study, metallic nanocavity array was fabricated as surface enhance Raman scattering (SERS) substrates by block copolymer directed self-assembly (BCP-DSA) and metal transfer (mTP) process. The combination of nanoimprint lithography and BCP-DSA made our patterning method simple and cost-effective. The reproducibility of our SERS substrate was achieved by using mTP method which was rarely mentioned in other’s works. Gold nanocavities with 10 nm gap, 30 nm height and 40 nm period were fabricated by an mTP process. Gold nanoslits with the same dimensions were also fabricated for comparison. The field enhancement properties of nanocavity with different structure were investigated numerically and experimentally. The localize field enhancement in the nanocavity is much stronger than that in the nanoslit. The SERS sensing result greatly agreed with the simulation result. The nanocavity substrate enhanced the SERS signals 5 times higher than the nanoslit substrate. This approach is a promising candidate for SERS substrate fabrication which eliminate trade-off between throughput and reproducibility.

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