Block Copolymer Derived Vertically Coupled Plasmonic Arrays for Surface-Enhanced Raman Spectroscopy

Abstract

A surface-enhanced Raman spectroscopy sensing template consisting of gold-covered nanopillars is developed. The plasmonic slab consists of a perforated gold film at the base of the nanopillars and a Babinet complementary dot array on top of the pillars. The nanopillars were fabricated by the incorporation of an iron salt precursor into a self-assembled block copolymer thin film and subsequent reactive ion etching. The preparation is easy, scalable, and cost-effective. We report on the increase in surfaceenhanced Raman scattering efficiency for smaller pillar heights and stronger coupling between the dot array and perforated gold film with average enhancement factors as high as 10 7 . In addition, the block copolymer-derived templates show an excellent relative standard deviation of 8% in the measurement of the Raman intensity. Finite difference time domain simulations were performed to investigate the nature of the electromagnetic near-field enhancement and to identify plasmonic hot spots.

Green Nanofabrication Opportunities in the Semiconductor Industry: A Life Cycle Perspective

“…For example, low temperature CVD can subsequently be used to selectively deposit titanium tetraisopropoxide (TTIP) into the block copolymer thin film template, as illustrated in Figure 3 part (c) [ 37 , 104 ]. Many metals, such as iron [ 107 ], nickel [ 134 ], copper [ 17 ], zinc [ 134 ], silver [ 135 ], gold [ 136 ], and others can also be deposited by metal ion precursor in ethanol solution, or low temperature vapour deposition [ 14 , 130 ]. The low-temperature nature of the vapour phase deposition process may eliminate the energy costs and the expenses associated with the employment of complex machinery and optical systems [ 137 ].…”

The effect of auxiliary complexing agent on silver crystallization and the application in SERS

“…Li等 [16] 将事先制备好的银 纳米立方体在油/水界面自组装成有序阵列, 接着负载 到聚(二甲基硅氧烷)薄膜表面形成的活性基底对罗丹 明6G的检测限可低至1.0×10 -9 mol/L, 同时SERS活性 的相对标准偏差可控制在12%左右. 以模板法为例, Akinoglu等 [17] 在纳米柱阵列表面沉积金纳米粒子, 得 到的位于纳米柱阵列底部的穿孔金薄膜和位于阵列顶 部的互补金纳米点阵列之间可产生垂直耦合等离子体 阵列, 其平均增强因子可达10 [17] . 电 流达到最大值后又快速下降, 随后缓慢变化, 对应的 是溶液中的银离子受到扩散控制向电极表面转移而后 放电结晶生长的过程 [18] .…”

Solvent Vapor Annealing, Defect Analysis, and Optimization of Self-Assembly of Block Copolymers Using Machine Learning Approaches

“…11 This combination of self-assembly with lithography is termed directed self-assembly (DSA) and has been primarily directed towards applications in microelectronics, including memory storage materials, 6,12,13 finFET, 5,14,15 and vias. [16][17][18] These nanopatterned substrates have also seen use as catalysts for growth of ordered nanowire arrays, [19][20][21] as a platform for protein detection, 22,23 separation membranes, [24][25][26][27] surface enhanced Raman spectroscopy (SERS) substrates, [28][29][30] anti-reflective coatings in photovoltaics, [31][32][33] and chemical and biomedical sensors. [34][35][36][37] The self-assembly of a monolayer of a given BCP on a flat, featureless surface results in a polycrystalline morphology with uncorrelated nano-to micron-sized domains, with a significant concentration of defects.…”