Laser-induced modification of glass–ceramics microstructure and applications V.P. Veiko a, * , Q.K. Kieu a , N.V. Nikonorov a , V.Ya. Shur a , A. Luches b , S. Rho a a St. Petersburg State University of Information Technologies, Mechanics and Optics 14 Sablinskaya Street, St. Petersburg 197101, Russia b University of Lecce, Department of Physics, Via Arnesano, 73100 Lecce, Italy Available online 8 April 2005 Abstract The laser-induced modifications in two kinds of glass–ceramics (GCs) with composition TiO 2 –SiO 2 (Sitall ST-50) and Li 2 O– SiO 2 (Fotoform) were investigated for fabricating optical elements. The laser-induced change of refractive index and surface relief constituted the first step of this task. The second stage was a chemical processing including ion exchange (Li $ Na, K, Rb, for ‘‘Fotoform’’ GCs) and etching of irradiated and non-irradiated areas. As a result of the above-mentioned processes, mini- and micro-optical components based on two GCs have been fabricated: lenses and lens arrays, waveguides and other waveguiding components, diffractive gratings, etc. # 2005 Elsevier B.V. All rights reserved. Keywords: Laser amorphization; Glass ceramics; Crystallization; Local heating; Micro-optics 1. Introduction Photonics as a technology for fabrication of opto- informatic devices is just living in the first stage of miniaturization and integration that was reached in microelectronics 50 years ago. This stage is character- ized by the formation of materials and components in a single process. Examples of such an approach could be the fabrication of thermo-photo-optical materials and components for holographic corrections of laser beam wave fronts [1], the fabrication of micro-optical components by laser densification of porous glasses [2], etc. Further development of miniaturization and integration in photonics should allow create photonics chips, combining different functions in a single monolithic block of specific material, whose structure is modified by different treatments. The most popular materials for such kind of investigations are semi- conductors (InGaAs type), ‘‘photonics’’ glasses and optical polymers. In the present work, a similar approach to glass– ceramics materials is performed. Glass–ceramics (GCs) have an amorphous structure with embedded micro- crystals that are responsible for their mechanical, chemical and optical properties. From the optical point www.elsevier.com/locate/apsusc Applied Surface Science 248 (2005) 231–237 * Corresponding author. E-mail address: veiko@lastech.ifmo.ru (V.P. Veiko). 0169-4332/$ – see front matter # 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2005.03.090