Low-pressure RF remote plasma cleaning of carbon-contaminated B4C-coated optics

Autor: R. Barrett, R. Dietsch, H. Moreno Fernandez, M. Thomasset, Guillaume Sauthier, Eric Pellegrin, V. Carlino, D. Rogler
Rok vydání: 2017
Předmět:
Zdroj: Dipòsit Digital de Documents de la UAB
Universitat Autònoma de Barcelona
Popis: Altres ajuts: the research by HMF is supported by funding from the "Generalitat de Catalunya, Departament d'Empresa i Coneixement" within the "Doctorats Industrials" program (dossier no. 2014 DI 037) Boron carbide (BC)-due to its exceptional mechanical properties-is one of the few existing materials that can withstand the extremely high brilliance of the photon beam from free electron lasers (FELs) and is thus of considerable interest for optical applications in this field. However, as in the case of many other optics operated at modern accelerator-, plasma-, or laser-based light source facilities, BC-coated optics are subject to ubiquitous carbon contaminations. These contaminations-that are presumably produced via cracking of CH and CO molecules by photoelectrons emitted from the optical components-represent a serious issue for the operation of the pertinent high performance beamlines due to a severe reduction of photon flux and beam coherence, not necessarily restricted to the photon energy range of the carbon K-edge. Thus, a variety of BC cleaning technologies have been developed at different laboratories with varying success [1]. Here, we present a study regarding the low-pressure RF plasma cleaning of a series of carbon-contaminated BC test samples via an inductively coupled O/Ar and Ar/H remote RF plasma produced using the IBSS GV10x plasma source following previous studies using the same RF plasma source [2, 3]. Results regarding the chemistry, morphology as well as other aspects of the BC optical coatings and surfaces before and after the plasma cleaning process are reported.
Databáze: OpenAIRE