Effects of substrate temperature on the laser damage threshold of sputtered SiO2 films

SiO2 films have been deposited by ion-beam sputtering techniques either without assistance or with Ar-ion assistance and the role of the substrate temperature during the deposition process on the film damage threshold by laser light at the wavelength of 308 nm (XeCl) has been investigated. The photoacoustic probe beam deflection technique has been used to determine damage thresholds and it is shown that this technique provides valuable information on the mechanisms leading to laser damage. It has been found that the samples deposited by the Ar-ion beam sputtering technique are characterized by higher damage thresholds at lower temperatures of the substrate than the SiO2 films deposited without ion assistance.