Organic resist based fabrication of integrated waveguides and ring resonators in thin-film lithium niobate

Thin-film lithium niobate (TFLN) is a promising candidate for photonic-based quantum information technology. This platform combines large nonlinear and electro-optical coefficients with the tight confinement and reduced footprint characteristic of integrated devices. Nonetheless, current high-performance devices in TFLN generally rely on the use of hydrogen-silsesquioxane (HSQ) resist, or on silicon dioxide hard-masks, adding complexity to the fabrication process. Here, we fabricate and characterize optical resonators in TFLN using readily available organic deep UV resist. This process constitutes an alternative for more accessible microfabrication of TFLN photonic devices.