Fully Tunable Silicon Nanowire Arrays Fabricated by Soft Nanoparticle Templating Rey, Marcel Elnathan, Roey Ditcovski, Ran Geisel, Karen Zanini, Michele Fernández Rodríguez, Miguel Ángel Naik, Vikrant V. Frutiger, Andreas Richtering, Walter Ellenbogen, Tal Voelcker, Nicolas H. Isa, Lucio Vertically aligned nanowires Nanoscale patterning Microgels Fluid interfaces 2D photonic crystals Optical cavities Financial support from the Swiss National Science Foundation grant PP00P2_144646/1. NHV kindly acknowledges fellowship support from the Alexander von Humboldt Foundation. MAFR acknowledges financial support from the COST action: Smart and Green Interfaces (STSM MP1106-14761) and would like to thank Prof. R. Hidalgo-Alvarez, Prof. M.A. Rodriguez-Valverde and Prof. M.A. Cabrerizo-Vilchez for supporting his COST fellowship. KG and WR acknowledge financial support from the German Research Foundation within the Collaborative Research Center SFB985 “Functional Microgels and Microgel Systems”. TE acknowledges financial support from the European Commission Marie Curie Career Integration Grant (grant no. 333821). We demonstrate a fabrication breakthrough to produce large-area arrays of vertically aligned silicon nanowires (VA-SiNWs) with full tunability of the geometry of the single nanowires and of the whole array, paving the way toward advanced programmable designs of nanowire platforms. At the core of our fabrication route, termed “Soft Nanoparticle Templating”, is the conversion of gradually compressed self-assembled monolayers of soft nanoparticles (microgels) at a water–oil interface into customized lithographical masks to create VA-SiNW arrays by means of metal-assisted chemical etching (MACE). This combination of bottom-up and top-down techniques affords excellent control of nanowire etching site locations, enabling independent control of nanowire spacing, diameter and height in a single fabrication route. We demonstrate the fabrication of centimeter-scale two-dimensional gradient photonic crystals exhibiting continuously varying structural colors across the entire visible spectrum on a single silicon substrate, and the formation of tunable optical cavities supported by the VA-SiNWs, as unambiguously demonstrated through numerical simulations. Finally, Soft Nanoparticle Templating is combined with optical lithography to create hierarchical and programmable VA-SiNW patterns. 2024-09-20T12:03:26Z 2024-09-20T12:03:26Z 2016 journal article Rey, Marcel. Fully Tunable Silicon Nanowire Arrays Fabricated by Soft Nanoparticle Templating. Nano Letters 16(1). DOI:10.1021/acs.nanolett.5b03414 https://hdl.handle.net/10481/94792 10.1021/acs.nanolett.5b03414 eng info:eu-repo/grantAgreement/EC/EuropeanCommission/333821 http://creativecommons.org/licenses/by-nc-sa/4.0/ open access Atribución-NoComercial-CompartirIgual 4.0 Internacional American Chemical Society