High aspect ratio lithium niobate ridge waveguides fabricated by optical grade dicing

Nadège Courjal (1) , Blandine Guichardaz (1) , Gwenn Ulliac (1) , Jean-Yves Rauch (1) , Benattou Sadani (1) , Hui-Hui Lu (1) , Maria-Pilar Bernal (1)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)

We report the development of a quick process for fabricating lithium niobate ridge waveguides with smooth walls, aspect ratios larger than 500 and side wall verticality of 88°. The method is based on optical grade dicing, and allows the fabrication of ridges with a top width of 1µm and a depth of more than 500µm. Smart-cut ridge waveguides and strongly confined proton exchanged ridge waveguides are demonstrated. We show that the method enables the fabrication of ridge waveguides with propagation losses as low as 0.5dB/cm. A new fabrication process is thus proposed for the fabrication of optical components with enhanced acousto-optic, electro-optic or nonlinear interactions. The high aspect ratios open opportunities toward the development of 3D photonic components in thin films of LiNbO 3, and toward hybrid integration of LiNbO 3 components.

Mots clés: Physical Sciences

Nadège Courjal, Blandine Guichardaz, Gwenn Ulliac, Jean-Yves Rauch, Benattou Sadani, et al.. High aspect ratio lithium niobate ridge waveguides fabricated by optical grade dicing. Journal of Physics D: Applied Physics, 2011, 44 (30), pp.305101. ⟨10.1088/0022-3727/44/30/305101⟩. ⟨hal-00637796⟩