Reactive ion etching of LiNbO3

We describe the reactive ion etching of LiNbO3 in gas mixtures containing CCl2F2, CF4, O2, and Ar. The effects of gas composition and pressure, in the range 1–10-μm total pressure are discussed. Because it is possible to replicate fine features (∼2000 Å) with control of etch profiles, we expect the process to be used for three-dimensional patterning of LiNbO3 for electro-optic and acoustic-optic devices.