Abstract

Thin films are widely used in many applications, especially, the transparent layers are commonly used as high reflective and antireflex coatings on optical elements. Moreover, several spectroscopic applications need microstructured thin films deposited on bulk dielectric. Many procedures have been developed for etching transparent dielectrics. The conventional multistep techniques (hidrofluidic etching [1], powder blasting [2], ion etching [3]) require contact mask preparation on the target surface. The laser-based direct and indirect methods, however, can provide a good alternative for micro- and submicrometer structuring of transparent dielectrics without the complicate preparation of contact masks. The laser-induced backside wet etching (LIBWE) [4] is one of the most promising and flexible and applicable indirect technique. It was recently demonstrated that the combination of LIBWE with the two-beam interferometric method (TWIN-LIBWE) is well suited for fabrication of submicrometer period gratings onto the surface of bulk fused silica [5]. In this paper we report on the fabrication of micrometer period grating structure in SiO₂, and ZrO₂ thin films with the use of TWIN-LIBWE.

© 2011 Optical Society of America