Open AccessMitigation of organic laser damage precursors from chemical processing of fused silica
Author(s) -
Salmaan H. Baxamusa,
Philip E. Miller,
Lana L. Wong,
R. Steele,
Nan Shen,
J. Bude
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.029568
Subject(s) - ultrapure water , materials science , polishing , impurity , dissolution , laser , chemical engineering , chemical mechanical planarization , etching (microfabrication) , thermal , solvent , optics , composite material , nanotechnology , chemistry , organic chemistry , physics , layer (electronics) , meteorology , engineering
Increases in the laser damage threshold of fused silica have been driven by the successive elimination of near-surface damage precursors such as polishing residue, fractures, and inorganic salts. In this work, we show that trace impurities in ultrapure water used to process fused silica optics may be responsible for the formation of carbonaceous deposits. We use surrogate materials to show that organic compounds precipitated onto fused silica surfaces form discrete damage precursors. Following a standard etching process, solvent-free oxidative decomposition using oxygen plasma or high-temperature thermal treatments in air reduced the total density of damage precursors to as low as <50 cm(-2). Finally, we show that inorganic compounds are more likely to cause damage when they are tightly adhered to a surface, which may explain why high-temperature thermal treatments have been historically unsuccessful at removing extrinsic damage precursors from fused silica.