Abstract

Optical waveguides have been produced for many years in LiNbO₃ by diffusing Ti metal from a thin deposited film at high temperature.¹ These waveguides have been the subject of much research and refinement.² For many applications, particularly those using relatively long wavelengths (1.3,1.5 microns) for optical communications, the low index change Δn and resulting large cross-sectional area of the diffused waveguide limits the efficiency of the electro-optic devices. Reported here is the development of a new technique for making optical waveguides in LiNbO₃ by directly implanting Ti. A solid phase epitaxial regrowth process² was employed to restore the amorphized crystal structure, making low loss guides (<1dB/cm) possible. Large Δn and small diffusion length can be achieved in this process that will improve significantly the efficiency of electro-optic guided wave devices.

© 1988 Optical Society of America