Nanosphere Lithography: Fabrication of Periodic Arrays of Nanoholes

Abstract

Polystyrene nanosphere (PSNs) with 500 nm in diameter can be shrunk when exposed to reactive ion etching (RIE) in various gases mixture (Ar, O2 and Ar/ O2) with varied duration of exposure time (5–25 s). These etched PSNs will act as lithography mask to fabricate periodic nanohole arrays (PNHAs), where the lift‐off of the PSNs will left the substrate surface with thin layer films of deposited Pt or Au with periodic nanoholes scattered on the substrate surface. We plotted the average diameter of the etched PSNs, later sputtered with 75.0 nm of Pt, used as lithographic mask to fabricate PNHAs with sizes ranging from 200–400 nm. Reducing the diameter of PSNs by means increased the gap between the PSNs will affect the amount of deposited Pt on the Si substrate, thus controlling the nanoholes size. PSNs were acting as nano‐templates which after removal process such as by sonicating the sample in organic solvent, can be useful in fabricating PNHAs that can be used as optical and catalysts research. Field Emission Scanning Electron Microscopy (FE‐SEM) was used to characterize the PSNs and PNHAs.