使用二步壓印製程實現具二維光柵結構之SERS基板

Two-dimensional grating structure implementation of SERS Substrate using two-step nanoimprinting process

呂維恩(Wei-En Lu)

指導教授 ： 郭文凱

國立虎尾科技大學/電機資訊學院/光電工程系光電與材料科技碩士班/碩士(2016年)

摘要

本論文主要提出以市售固定週期的一維光柵作為母模，使用二步奈米壓印方式產生二維光柵結構來製作表面增強拉曼散射(SERS)基板，並將二維光柵旋轉使其晶格週期接近激發光波長的方向對準較強的激發光偏振方向以產生較強表面電漿偏極子(SPP)來增強拉曼信號。在基板製作方面，我們利用市售1800 lines/mm的一維光柵(週期約555 nm)作為母模，翻印出具有一維光柵的矽膠模仁，以紫外光固化奈米壓印技術壓印一維光柵在的玻璃基板上，控制照光劑量，在紫外光膠呈半固化狀態時脫模，將基板轉90度，再用一維光柵的模仁進行第二次壓印即可產生二維光柵結構，最後在表面上蒸鍍一層金膜即完成SERS基板製作。在拉曼訊號量測上，使用InPhotonics公司的光纖式拉曼探頭（型號:RPB fiber optic probe）配合Ocean Optics公司的光譜儀Maya2000pro及波長785 nm二極體雷射作為激發光源，我們量測此系統照射在基板樣品上的激發光呈橢圓偏振，在橢圓的長軸方向有較大的光強度。在樣品溶液部分我們使用苯甲酸以溶劑蒸發沉積方式均勻附著在二維光柵基板上，再將基板放置旋轉平台上，旋轉基板使二維光柵晶格週期接近785 nm（激發光波長）的方向對準激發光橢圓偏振的長軸時，可得到最強的拉曼信號。模擬部份我們使用EM Explorer軟體對不同偏振方向的激發光產生電場作探討，來驗證實驗結果。本論文提出的技術可以低成本的方式製作表面增強拉曼散射基板並產生最佳的拉曼信號增強效應。

關鍵字

二維光柵 ； SERS基板 ； 增強型拉曼

並列摘要

This study proposes using a commercially available fixed cycle master mold a one-dimensional grating as using a two-step nanoimprint way to produce a two-dimensional grating structures to produce surface-enhanced Raman scattering (SERS) substrate, and the two-dimensional raster rotate it lattice period approaching direction excitation wavelength of the excitation light of the strong alignment of the polarization direction of the surface to produce a surface plasmon polariton (SPP) to enhance the Raman signal.
The substrate production, we use a commercially available 1800 lines / mm grating one-dimensional (a period of about 555 nm) as a master mold, reproduced a silicone mold having a one-dimensional grating benevolence, UV curing nanoimprint technology to imprint a dimensional grating on a glass substrate to control illumination dose, release when UV glue was semi-cured state, the substrate is rotated 90 degrees, then the mold core one-dimensional grating for a second imprint to produce two-dimensional raster structure, and finally a layer of gold deposited on the surface of the membrane to complete the SERS substrate production.
In Raman signals measured using InPhotonics company's fiber-optic Raman probes (Model: RPB fiber optic probe) with Ocean Optics spectrometers are Maya2000pro and wavelength 785 nm diode laser as the excitation source, we measured the system irradiating excitation light on the sample substrate elliptical polarization, greater light intensity in the direction of the long axis of the ellipse. We use the portion of the sample in a solution of benzoic acid to the solvent evaporation deposition method uniformly adhered to the two-dimensional grating substrate, then the substrate is placed on a rotating platform, rotating the substrate so that a two-dimensional lattice grating period nearly 785 nm (excitation wavelength) in the direction of elliptically polarized excitation light quasi-major axis, the strongest Raman signal can be obtained. Most simulation software we use EM Explorer excitation light of different polarization directions for generating an electric field to explore, to verify the results. Techniques presented in this thesis can be a low-cost way to create surface-enhanced Raman scattering substrate and produce the best signal enhancement Raman effect.

並列關鍵字

Two-dimensional grating ； SERS ； Enhanced Raman

參考文獻

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