Effects of Chemical Etching with Sulfuric Acid on Glass Surface

Glass slides were chemically etched with nitric acid using five different methods. We investigated the effects of chemical etching treatments on such properties as chemical composition, surface roughness, transmittance, and thermal stability of the glass. Sodium, calcium, and aluminum atoms in the surface of the glass are effectively reduced by chemical etching with nitric acid. Especially, boiling the glass in a 70% nitric acid solution for 30 min is more effective in the reduction of sodium, calcium, and aluminum atoms at the surface of the glass than other etching methods with nitric acid. The surface morphologies of the glasses were very similar regardless of the chemical etching treatments with nitric acid etchant. Root-mean-square surface roughness of the bare glass was 0.58 nm but that of the glass etched with nitric acid was ranged from 5.4 to 6.8 nm. Sodium concentration at the glass surface was largely reduced from 2.44% to 0.25%. In order to investigate the thermal stability of the glass, the b...