Fabrication of LiTaO3 periodic surface structures by a single excimer laser pulse through a phase mask grating

摘要

Abstract: Surface corrugations with periodic of 2 $mu@m and a depth of approximately 150 nm have been fabricated in lithium tantalate (LiTaO$-3$/) monocrystal wafers. Morphologies of the corrugations were studied with an atomic force microscope. These corrugations were first produced by a single excimer laser pulse through a diffractive optical element, and the optical quality of the periodic structures is demonstrated by its characteristics as a gratings coupler in a LiTaO$-3$/ planar waveguide. !9