UV coatings using Ta₂O₅-SiO₂ quantized nanolaminates

¹ RhySearch, Institute for optical coatings and characterization, Werdenbergstrasse 4, 9470, Switzerland
² Evatec Ltd., Hauptstrasse 1a, 9477 Trübbach, Switzerland
³ EMPA, Laboratory for Mechanics of Materials & Nanostructures, Feuerwerkstrasse 39, 3602 Thun, Switzerland

^* Corresponding author: manuel.baertschi@rhysearch.ch

Published online: 31 October 2024

Abstract

In the last few years, quantized nanolaminates (QNL) have become increasingly popular as a metamaterial in the development for optical coatings. Experiments were often performed using IBS or ALD coating techniques, which yield excellent accuracy but are very time consuming to coat. By using a magnetron sputter system with rotating substrate table, we are able to produce these layers at very high deposition rates and to use these nanolaminates as standalone high index material in optical designs. Due to the properties of QNL to increase the band energy and thus shift the absorption edge into lower wavelength ranges, it is possible to create designs in the UV range that would not be possible with simple Ta₂O₅-SiO₂ material combination in regular designs. In this work we show a selection of different designs such as anti-reflective coatings, mirrors and short pass filters at wavelengths from 266-355nm which covers an important range in laser applications.