Deep UV laser induced fluorescence in fluoride thin films

Fluorescence experiments have been performed to study the interaction of 193-nm laser radiation with dielectric thin films of LaF/sub 3/, AlF/sub 3/, and MgF/sub 2/. Spectral- and time-resolved measurements reveal the presence of cerium in LaF/sub 3/ and the influence of hydrocarbons in MgF/sub 2/ and LaF/sub 3/. Virtually no fluorescence response is observable in the case of AlF/sub 3/. Supplementary measurements on multilayer stacks confirm the contribution of hydrocarbon and cerium emission in high-reflective UV mirrors upon ArF excimer laser irradiation. Energy density dependent measurements indicate a linear absorption process as the origin of UV laser induced fluorescence in LaF/sub 3/. Luminescence calculations are applied as a helpful tool in order to account for interference effects that are inherently to be found in the multilayer emission spectra.