This paper addresses the fabrication issues related to phase masks for photonics applications. A commercial e-beam lithography system operating at 50 kV is used to pattern a suitable resist on a fused silica substrate; the printed image is then transferred into the active material by means of Reactive Ion Etching in a fluorine-based chemistry. The optimised fabrication process, which will be described in detail, allows sub-500 nm resolution, centimetre long, phase masks with zero order suppression down to less than 3% and negligible field stitching. Some of the fabricated phase masks are used to create Bragg gratings into the core region of industry-grade optical fibres.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering