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In order to understand the damage mechanisms inside the optics of the high power laser facilities, a model sample has been prepared by introducing gold nanoparticles into a silica film. The mean diameter of the gold clusters is 2.5 nm. Different parts of the sample were irradiated at wavelength 355 nm and fluences up to 1 J/cm2. By looking with x-ray photoelectron spectroscopy at the intensity of the Au 4f peak relative to that of the Si 2p peak, a surface Au density enrichment is observed. We interpret this as indicating that the gold atoms migrate toward the surface upon the laser irradiation. [ABSTRACT FROM AUTHOR]

Electron-induced x-ray emission spectroscopy (EXES) associate with a semi-empirical electron scattering model is used to determine thicknesses between 2 and 21 nm of SiO[SUB2] films on Si. The small charging effect occurring upon electron irradiation is taken into account by introducing a retarding potential in the model. The results are in very close agreement with those obtained by spectroscopic ellipsometry and x-ray reflectometry. It is demonstrated that the EXES with its model is a well-suited method for the quantitative analysis of thin insulating films with an uncertainty lower than 5%. [ABSTRACT FROM AUTHOR]