Wet chemical etching of silicate glasses in hydrofluoric acid based solutions

Abstract

The etching of silicate glasses in aqueous hydrofluoric acid solutions is applied in many technological fields. In this review most of the aspects of the wet chemical etching process of silicate glasses are discussed. The mechanism of the dissolution reaction is governed by the adsorption of the two reactive species: HF and HF 2 and the catalytic action of H + ions, resulting in the breakage of the siloxane bonds in the silicate network. The etch rate is determined by the composition of the etchant as well as by the glass, although the mechanism of dissolution is not influenced. In the second part of this review, diverse applications of etching glass objects in technology are described. Etching of SiO= and doped Si02 thin films, studied extensively for integrated circuit technology, is discussed separately.

Analysis of substrate coverage of hybrid halide perovskite thin films deposited on glass

“…In all cases, the best results were obtained using a buffered oxide etch of HF (2 min). This is a method widely used to etch silicon dioxide in integrated circuit technologies [9]. A remarkable result can be appreciated in Figure 3, where part of the substrate was treated with BOE and the other with common cleaning method (acetone/isopropyl alcohol).…”

“…Preliminary probes of wettability lead us to discard substrates of polymethyl methacrylate (PMMA), sapphire (α-Al 2 O 3 ), and different silicon wafers. Consequently, in the present work we propose some treatments on glass substrates [8,9]. Finally, we also study perovskite coverage over substrates with conductive films used as contacts in solar cells, such as fluordoped tin oxide (FTO) over glass.…”

Rapid Plasma Etching for Fabricating Fused Silica Microchannels

“…Wet etching processes using hydrofluoric acid or potassium hydroxide solutions are conventionally available in the fabrication of microchannels. [12][13][14][15] However, wet etching processes often generate undesired over-etching or etching defects arising from the difficulty in controlling the solution composition and reaction times, and is also tainted by the formation of non-rectangular shapes due to isotropic etching and low aspect ratios (usually lower than 1.0). Moreover, such strong acidic solutions are toxic and not environmentally friendly.…”

Etched glass surfaces, atomic force microscopy and stochastic analysis

“…Also micro and nano-structuring of glass surfaces is important for the production of many components and systems such as gratings, diffractive optical elements, planar wave guide devices, micro-fluidic channels and substrates for (bio) chemical applications 7 . Wet etching is also well developed for some of these applications 8,9,10,11,12,13,14 .…”