Broadband antireflective silicon nanostructures produced by spin-coated Ag nanoparticles

Abstract

We report the fabrication of broadband antireflective silicon (Si) nanostructures fabricated using spin-coated silver (Ag) nanoparticles as an etch mask followed by inductively coupled plasma (ICP) etching process. This fabrication technique is a simple, fast, cost-effective, and high-throughput method, making it highly suitable for mass production. Prior to the fabrication of Si nanostructures, theoretical investigations were carried out using a rigorous coupled-wave analysis method in order to determine the effects of variations in the geometrical features of Si nanostructures to obtain antireflection over a broad wavelength range. The Ag ink ratio and ICP etching conditions, which can affect the distribution, distance between the adjacent nanostructures, and height of the resulting Si nanostructures, were carefully adjusted to determine the optimal experimental conditions for obtaining desirable Si nanostructures for practical applications. The Si nanostructures fabricated using the optimal experimental conditions showed a very low average reflectance of 8.3%, which is much lower than that of bulk Si (36.8%), as well as a very low reflectance for a wide range of incident angles and different polarizations over a broad wavelength range of 300 to 1,100 nm. These results indicate that the fabrication technique is highly beneficial to produce antireflective structures for Si-based device applications requiring low light reflection.

Ultra-Low-Reflective, Self-Cleaning Surface by Fabrication Dual-Scale Hierarchical Optical Structures on Silicon

“…Dry etching uses an ion source with specific energy to bombard the substrate material and causes it to peel to achieve etching. With continuous development, dry etching has led to a variety of processes, such as reactive ion etching (RIE) [34][35][36][37], the inductively coupled plasma etching (ICP) process [38][39][40], the ion beam etching process, and deep reactive ion etching (DRIE) [41]. RIE is an etching method that produces both physical and chemical effects.…”

Surface Nanostructures Formed by Phase Separation of Metal Salt–Polymer Nanocomposite Film for Anti-reflection and Super-hydrophobic Applications

“…Yet, this technique generally requires a specific etching system or complex process that limits its choice of substrate materials [ 17 , 19 ]. Another popular technique is the deposition or coating of a metallic film on a substrate followed by thermal annealing to achieve sub-micrometer-sized metal islands that can be used as hard mask for etching the substrate [ 20 – 25 ]. Yet, such island film formation needs high cost vacuum deposition and/or high annealing temperature conditions that limits their usage.…”