Jung Bongsu, Frey Wolfgang
J Nanosci Nanotechnol. 2015 Jan;15(1):688-92. doi: 10.1166/jnn.2015.9057.
Nanowell structure has been attractive in plasmonics, surface enhanced Raman scattering, nanocrystal synthesis, and biomolecular immobilization. Conventional nanowell structures have been carved into continuous thin metal films. This letter focuses on the fabrication and characterization of triangular gold nanowell arrays embedded in a back-filled non-metallic and transparent substrate. The nanowell dimensions can be controlled to produce an optically tunable localized surface plasmon resonance (LSPR) as a plasmonic sensor. AFM and LSPR spectroscopy confirm that the triangular Au nanowell structures are partially embedded in the surface of a transparent glass substrate to protect the shape and sharp features of the nanowell. Experimental spectral results and numerical calculations show that the extinction maximum of the LSPR is located in the NIR range, and correlates linearly with the base thickness of the nanowell. Numerical calculations to analyze the extinction spectrum of gold nanowell show that scattering of the nanostructure is dominant to compare to its absorption. LSPR-tunable nanowells can potentially be used for plasmonic sensors and biomolecular docking system platforms.
纳米阱结构在等离子体学、表面增强拉曼散射、纳米晶体合成及生物分子固定方面具有吸引力。传统的纳米阱结构是在连续的薄金属膜上刻蚀而成。本文着重于对嵌入回填的非金属透明衬底中的三角形金纳米阱阵列的制备及表征。纳米阱尺寸可加以控制，以产生作为等离子体传感器的光学可调谐局域表面等离子体共振（LSPR）。原子力显微镜（AFM）和LSPR光谱证实，三角形金纳米阱结构部分嵌入透明玻璃衬底表面，以保护纳米阱的形状和尖锐特征。实验光谱结果和数值计算表明，LSPR的消光最大值位于近红外范围内，且与纳米阱的底部厚度呈线性相关。分析金纳米阱消光光谱的数值计算表明，与吸收相比，该纳米结构的散射占主导地位。LSPR可调谐纳米阱有潜力用于等离子体传感器和生物分子对接系统平台。
