Highly Sensitive Deep-Silver-Nanowell Arrays (d-AgNWAs) for Refractometric Sensing.
writer：Xueyao Liu, Wendong Liu, Liping Fang, Shunsheng Ye, Huaizhong Shen, and Bai Yang.
keywords：deep-silver-nanowell arrays, colloidal lithography, nanohole, plasmonic, nanostructure, refractometric sensing
source：期刊
specific source：Nano Res.
Issue time：2017年
Large-area deep-silver-nanowell arrays (d-AgNWAs) for plasmonic sensing
were manufactured by combining colloidal lithography with metal deposition.
In contrast to most previous studies, we shed light on the outstanding sensitivity
afforded by deep metallic nanowells (up to 400 nm in depth). Using gold nanohole
arrays as a mask, a silicon substrate was etched into deep silicon nanowells,
which acted as a template for subsequent Ag deposition, resulting in the
formation of d-AgNWAs. Various geometric parameters were separately tailored
to study the changes in the optical performance and further optimize the sensing
ability of the structure. After several rounds of selection, the best sensing
d-AgNWA, which had a Ag thickness of 400 nm, template depth of 400 nm,
hole diameter of 504 nm, and period of 1 μm, was selected. It had a sensitivity
of 933 nm·RIU–1, which is substantially higher than those of most common thin
metallic nanohole arrays. As a proof of concept, the as-prepared structure was
employed as a substrate for an antigen-antibody recognition immunoassay,
which indicates its great potential for label-free real-time biosensing.