Abstract

Measurements of mode indices have been used, along with the WKB method, to determine the index profile of partially buried double diffused waveguides. The waveguides were fabricated using the two-step Ag⁺ exchange process in BK7 glass. This procedure can, with suitable masking, be used in fabricating a variety of optical components. To make devices with predictable characteristics, waveguide parameters such as maximum index change, index profile, effective guide depth must be correlated to the fabrication parameters. To fabricate the guides, the masked substrate is first immersed in a 2% molar solution of AgNO₃ in NaNO₃ to form deep waveguide regions, and then reimmersed, unmasked, in a 0.25% solution to form partially buried high index regions in a planar, linear-index waveguide.

© 1989 Optical Society of America