title: Effects of deep wet etching in HF/HNO3and KOH solutions on the laser damage resistance and surface quality of fused silica optics at 351 nm.
abstract: We investigate the interest of deep wet etching with HF/HNO3or KOH solutions as a final step after polishing to improve fused silica optics laser damage resistance at the wavelength of 351 nm. This comparison is carried out on scratches engineered on high damage threshold polished fused silica optics. We evidence that both KOH and HF/HNO3solutions are efficient to passivate scratches and thus improve their damage threshold up to the level of the polished surface. The effect of these wet etchings on surface roughness and aspect is also studied. We show that KOH solution exhibit better overall surface quality that HF/HNO3solution in the tested conditions. Given the safety difficulties associated with the processing with HF, KOH solution appears as a pertinent alternative to HF deep wet etching.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Pfiffer
authors.forename: Philippe
authors.initials: P
authors.lastname: Cormont
authors.forename: Evelyne
authors.initials: E
authors.lastname: Fargin
authors.forename: Bruno
authors.initials: B
authors.lastname: Bousquet
authors.forename: Marc
authors.initials: M
authors.lastname: Dussauze
authors.forename: Sébastien
authors.initials: S
authors.lastname: Lambert
authors.forename: Jérôme
authors.initials: J
authors.lastname: Néauport