Damage thresholds of HfO 2 /SiO 2 and ZrO 2 /SiO 2 high reflectors at 1.064 microns deposited by reactive DC magnetron sputtering

Abstract

HfO 2 /SiO 2 and ZrO 2 /SiO 2 high reflectors at 1.064 µm were deposited by pulsed reactive DC magnetron sputtering. These dielectric thin film high reflectors were deposited with and without the use of an electron source. The electron source greatly decreased arcing of the magnetrons during the deposition process resulting in thin films with fewer defects. The high reflectors were laser damage tested at 1.064 µm. The optical properties of the thin film coatings were characterized prior to laser damage testing. Optical characterization techniques included angle resolved scatter (BRDF), total integrated scatter (TIS), and adiabatic calorimetry. The dependence of the laser damage threshold and optical properties on deposition conditions is reported.

Experimental Study of Irradiation of Thin Oxide and Mo/Si Multilayers by High Brightness Broadband VUV/UV Radiation and Their Degradation

“…In the work [10] UV-irradiation treatment increased the refractive index for ZrO 2 /SiO 2 25-layer film. There is an interest in damage study for HfO 2 /SiO 2 and ZrO 2 /SiO 2 multilayers under high radiation loads also [11,12]. Radiation durabil-ity of the mentioned oxide multilayers is about ≈20-32 J/cm 2 [13] under visible and IR laser radiation.…”