微图案化金衬底表面等离子体共振光学特性  

Surface plasmon resonance coupling effect of micro-patterned gold film

作　　者：陆乃彦[1] 余雪健 万佳伟 翁雨燕 郭俊宏[2] 刘宇 

机构地区：[1]江南大学食品科学与技术国家重点实验室,无锡214122 [2]南京邮电大学光电工程学院,南京210023 [3]苏州大学软凝聚态物理与交叉研究中心,苏州215006 [4]亥姆霍兹德累斯顿罗森道夫研究中心离子束物理与材料研究所,德国德累斯顿01328

出　　处：《物理学报》2016年第20期255-260,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:31401589;21204058;61505085);亥姆霍兹博士后项目(批准号:PD-146);江苏省研究生科研创新计划(批准号:SJLX15-0379);江苏省食品安全与质量控制协同创新中心资助的课题~~

摘　　要：表面增强拉曼在复杂的生物体系检测方面具有极高的灵敏度,因而具有广泛的生物化学应用前景.本文通过时域有限差分方法对不同形貌金薄膜的拉曼表面增强情况进行了研究.在实验上通过电子束曝光和软模板压印技术制备了相应的衬底并对常规目标物胱氨酸及三聚氰胺的拉曼光谱进行了测量.结果表明,单位面积内结构越复杂,表面增强拉曼越明显.表面增强拉曼散射光谱和场分布特性的计算与实验较为符合,为进一步使用表面增强拉曼作为研究手段提供指导和理论依据.Surface-enhanced Raman scattering has a high sensitivity in the detections of complex biological systems, and it has a lot of potential applications in food inspection, biological imaging and biosensors in biochemistry, etc. Here, we investigate the surface Raman enhancements on gold films of different morphologies and further simulate the enhancements by using the finite difference time domain.To prepare the substrates with different morphologies, polymethyl methacrylate（PMMA） is spin coated 2000 rpm in one minute on a silicon wafer, followed by annealing at 180℃ for 5 min. Then, PMMA is etched by a 20 k V electron beam lithography. With the PMMA used as a soft imprint template, polydimethylsiloxane（PDMS） is dropped on the template then removed gently from the template after drying at 60℃ for 4 h. Finally, a gold thin film is prepared on the PDMS by magnetron sputtering with a current of 10 m A for 15 min. We design two kinds of morphologies： a four-way grid and a square morphology. The dimension of the four-way grids is 40 μm and the grid width is 4 μm.The dimension of the square is also 4 μm. The cystine and melamine solutions with concentrations of 50, 100, 200 and400 ppm are deposited on the surfaces of the gold thin film, respectively. The Raman spectra of cystine and melamine solutions are measured on the substrates with four-way grids and dot arrays. The Raman spectra of cystine on two kinds of substrates show no obvious difference. Due to the relatively small enhancement of melamine, the Raman peaks of melamine solutions of concentrations 50 and 100 ppm on the substrate of square morphologies are not easy to detect.On the contrary, all of the Raman spectra of melamine on the substrate of four-way grid morphologies are clear. The result indicates that the substrate with four-way grids has better sensitivity and enhancement performance.To verify the influence of the morphologies of the substrates on surface Raman enhancement and understand the mechanism of the enhancement, we simulate the

关 键 词：表面增强拉曼 软模板压印 时域有限差分 表面微结构 

分 类 号：O657.37[理学—分析化学]