Fabrication of large-area nickel nanobump arrays

Abstract

Nanostructures have found wide applications in biochemical sensors and optical devices. Therefore, fabrication techniques are required to be suitable for preparing large-area nanopatterns at high throughput and low cost. This paper presents such an approach for fabricating hexagonally close-packed nickel nanobump arrays by a combination of monolayer self-assembly (MSA), poly (dimethylsiloxane) (PDMS) moulding and electroforming. A monolayer of polystyrene (PS) nanospheres on a substrate was used as a template for replicating the PDMS nanobowl mould. Good uniformity and smooth internal surface were observed in the nanobowl arrays. Highly ordered nickel nanobump arrays were fabricated by electroforming with the PDMS mould. The geometry of the nickel nanobumps can be tuned through changing the film thickness of the conductive layer and the electroforming material can also be extended to other metals and alloys. The simplicity and low cost of this approach may make widespread applications of these nickel nanopatterns possible.