[原创] Laser damage resistance of silica thin films

Laser damage resistance of silica thin films deposited by Electron Beam Deposition, Ion Assisted Deposition, Reactive Low Voltage Ion Plating and Dual Ion Beam Sputtering

L. Gallais, a, , , H. Krola, J.Y. Natolia, M. Commandréa, M. Cathelinauda, L. Roussela, M. Lequimea and C. Amraa

aInstitut Fresnel (UMR CNRS 6133) - Université Paul Cezanne - Université de Provence - Ecole Centrale Marseille, Domaine Universitaire de St Jérôme - 13397 Marseille Cedex 20 - France

Received 24 April 2006;  revised 27 September 2006;  accepted 6 October 2006.  Available online 1 December 2006.




Abstract
The laser damage resistance of optical coatings is a key point for a large number of applications. The aim of this work is to test and analyze the laser damage resistance of a thin film material commonly used for high power applications (SiO2) and deposited with different techniques: Electron Beam Deposition, Ion Assisted Deposition, Low Voltage Reactive Ion Plating and Dual Ion Beam Sputtering. The laser damage thresholds of these coatings were determined at 1064 nm and 355 nm using nanosecond pulsed YAG lasers, with a 1-on-1 test procedure. The results are then compared and discussed: we found different behaviours that we link to laser damage initiators of different nature and densities. The dense thin films (obtained with ion assistance) were found to be highly resistant to laser damage.

Keywords: Laser damage; Optical coatings; Silicon oxide; Evaporation; Sputtering