Fabrication of plasmonic nanopillar arrays based on nanoforming

[Display omitted] •A new fabrication method for ordered plasmonic nanopillar array is developed.•Au-capped nanopillar arrays exhibit higher refractive index sensitivity.•Au-capped nanopillar arrays with Ag coating show good performance as SERS substrates. A new fabrication method for realizing ordered nanopillar array is reported in this paper. First, a metallic nanodot array is prepared by combining two techniques, viz., nano-grid patterning by Nanoplastic Forming (NPF) and dot agglomeration by thermal dewetting. These processes do not include complicated and expensive procedures such as electron beam lithography. Then Au-capped nanopillar arrays are produced by reactive ion etching (RIE). In the refractive index sensing application, it is shown that the sensitivity of the Au-capped nanopillar array is higher than that of the Au nanodot array. The plasmonic nanopillar arrays with Ag coating are used as SERS-active substrates, which exhibit good performance.