A template-free, more environmentally friendly approach for glass micro-texturing

Yuhui Jin,Kelleen K Hughes,Aize Li,Robert R Hancock,David L Weidman,David E Baker,Ross J Stewart,Ruchirej Yongsunthon

doi:10.1038/s41598-022-04930-8

Abstract

Micron and nanometer size textured silicate glass surfaces are of interest in consumer electronics, photovoltaics, and biosensing applications. Typically, texturing glass surfaces requires applying a patterned mask or a pre-etching treatment (e.g. sandblasting) on the glass substrate, followed by a mask transferring or etching process using a fluoride-containing compound. The major challenges of such a process are the complexity and cost of masking, and the safety and environmental concerns around the usage and disposal of hydrofluoric acid. Here, we describe a template-free method to construct micron-sized and submicron-sized texture on isotropic glass surfaces in one step. The new texturing mechanisms are well supported by experimental data and peridynamic simulations. With this novel strategy, the etchant uses fluoride-free chemicals such as citric acid to texture silicate glass. Etchant concentration, etch temperature, time, and additives are the primary parameters that dictate the texturing process. Surface feature size and depth can be independently controlled by tuning the leaching and chemical polishing process. We hope this study can trigger more research on novel and more environmentally friendly texturing of isotropic materials.

Highlights

Micron and nanometer size textured silicate glass surfaces are of interest in consumer electronics, photovoltaics, and biosensing applications
Glass leaching is a process through which glass modifiers and some glass formers can be exchanged from the silica network by hydronium ions (H3O+) under acidic conditions[22,23]
Because the leaching layer has a lower molar volume compared to the bulk glass and tends to shrink, the thickening of the leaching layer starts to build up a surface tensile stress (σ)

Summary

Introduction

Micron and nanometer size textured silicate glass surfaces are of interest in consumer electronics, photovoltaics, and biosensing applications. The new texturing mechanisms are well supported by experimental data and peridynamic simulations With this novel strategy, the etchant uses fluoride-free chemicals such as citric acid to texture silicate glass. Silicate glass surfaces are typically textured by sandblasting and etching, wet chemical etching, and sol–gel deposition processes[12,13,14,15] In these processes, random surface features of ten to hundreds of microns in size are generated by mechanical subsurface damage followed by e tching[13], in-situ growth of inorganic micro-structural masking on glass during e tching[12,14], or the non-conformal deposition of silica sol–gel droplets on a glass surface[15]. The use of hydrofluoric acid (HF) or fluoride compounds in the above-mentioned techniques for microfabrication, raises concerns for safety and waste disposal[19,20]

Methods

Results

Conclusion