Silica layers as masks in Ag+-Na+ ion exchange processes

• Sol-gel silica layers were applied as masks in ion-exchange processes.
• Silver ions concentration profiles were measured below masked and unmasked areas.
• Channel waveguides were fabricated with application of sol-gel silica masks.

The paper present the application of sol-gel derived silica layers as masks in selective ion exchange processes. These layers were deposited on soda-lime glass substrates, subjected then to the ion exchange processes using liquid source of admixture in the form of a AgNO3:NaNO3 solution with a molar fraction of silver κAg = 0.0025. The concentration of silver in the masked and non-masked areas of the glass were examined with the use of Scanning Electron Microscope/Energy-Dispersive X-ray Spectroscopy (SEM/EDS). The resulting silver concentration profiles allowed to estimate the masking properties of silica layers. Using sol-gel silica films as masks for selective ion-exchange processes, the multimode strip waveguides were produced.