Effects of chemical etching with hydrochloric acid on a glass surface

Abstract

Glass slides were chemically etched with hydrochloric acid using three different methods. We investigated the effects of chemical etching treatments on such properties as chemical composition, surface roughness, and relative transmittance of the glass. Sodium, calcium, and aluminum atoms at the glass surface were effectively reduced by chemical etching with hydrochloric acid. Boiling the glass in a 36% hydrochloric acid solution for 30 min was more effective in reducing sodium, calcium, and aluminum atoms at the surface of the glass than any of the other etching methods using hydrochloric acid. Surface morphology of the glass was very different with chemical etching treatments with hydrochloric acid etchant. Root-mean-square surface roughness of the bare glass was 0.58 nm, but the roughness of the glass etched with hydrochloric acid ranged from 5.4 to 6.8 nm. The sodium concentration at the glass surface was greatly reduced, from 2.7% to 0.2%. The depth that was affected by chemical etching with hydrochloric acid was about 70nm. (C) 2000 American Vacuum Society. [S0734-2101(00)06205-9].