An optical grating filter dry-etched on a LiNbO₃ substrate

抄録

We fabricated an etched grating filter on a Ti-diffused waveguide in LiNbO₃ using inductively coupled plasma etching with C₄F₈/Ar as an etching gas, which has an etching rate of 85.1nm/min. The etched grating filter had a reflectivity of 35% and a bandwidth of 0.02nm. Maximum reflectivity was obtained when the electric field of an incident beam was perpendicular to the grating.