Float glass surface preparation methods for improved chromium film adhesive bonding

Abstract

Contact angle measurements using method based on B-spline snakes (active contours) were applied to investigate surface wettability properties of commercial soda-lime-silica float glass subjected to various surface preparation methods. The comparative evaluation of vacuum evaporated chromium thin film adhesion strength to float glass treated under different surface preparation methods was performed using scratch tests. Also, the influence of float glass substrate heating for chromium thin film adhesion strength was investigated. Surface activation and contamination removal by O 2 plasma process and RCA-1 surface preparation method revealed the best results, where surfaces were free of hydrophobic contaminants with low contact angles ranging from 4° to 8°. For majority of float glass surface preparation methods the contact angles were observed slightly higher for the tin side as compared with air side. Soda-lime-silica float glass surface wettability properties of both sides were equalized during bombardment in RIBE unit by Ar + ion beam. O 2 plasma process and RCA-1 surface preparation method for float glass resulted in a higher value of the thin chromium film adhesion to the float glass substrate as measured from the average critical normal force (O 2 plasma 0.169 N; RCA-1 0.14 N) in scratch tests. The float glass substrate heating (100 °C) in the vacuum chamber before chromium thin film evaporation process resulted in even higher value of the thin chromium film adhesion to the float glass substrate.