Effect of two organic contamination modes on laser-induced damage of high reflective films in vacuum

The impact of two organic contamination modes of toluene on the damage characteristics of a high reflective film (HR) at 1064 nm is investigated. The laser-induced damage modifications of HR films are locally analyzed by the Raman techniques, optical microscopy and scanning electron microscopy (SEM). It is found that liquid phase toluene decreases laser-induced damage threshold (LIDT) and gaseous phase toluene seems to be benign and increases the LIDT of the HR film. A possible damage mechanism is analyzed and discussed.