Cleaning and anti-reflective (AR) hydrophobic coating of glass surface: a review from materials science perspective

This article reviews the principles, mechanisms and comparisons of glass surface cleaning by various wet chemical and dry cleaning methods, including acid-base-solvent combinations, HF etching, chelation, vapor degreasing, UV-ozone, oxygen plasma, heating/pyrolysis, ultrasonic and laser treatments. This article also covers four major hydrophobic coating strategies, namely hydrosilylation, silanization, plasma treatment and DC sputtering, along with their process-wise applications. A special emphasis is given on the silanization process: its mechanism, factors affecting, choices of solvents and precursors, and limitations, which is utilized in anti-reflective (AR) sol-gel coating formation as well. Some of the common surface analytical techniques, its utility and reported data has also been reviewed in this context. Finally, a section has been devoted to anti-reflective (AR) and transmittance properties, elucidating the theory and methods of AR coating generation, factors affecting and related literature reports. The challenge lies in coming up with non-harsh cleaning procedures and water-based hydrophobic coatings, with an eye for application in ecological proximity.