CHARACTERIZATION AND DEPOSITION OF OXIDE-FILMS BY LASER-ASSISTED ELECTRON-BEAM EVAPORATION (LEBE) FOR OPTICAL APPLICATIONS

In the laser assisted electron beam evaporation (LEBE) a fused silica substrate is heated by cw CO2 laser irradiation before and during film condensation. HfO2 and Y2O3 films are prepared with this technique. T he optical and structural properties of the coatings are investigated by spectral-photometric transmission measurement (refractive index), l aterally resolved ellipsometry (lateral index and thickness profile ca lculations), and X-ray diffraction (structure). The surface morphology is characterized by lateral force microscopy, a special mode of atomi c force microscopy. Laser damage threshold values are also studied at 248 nm. It is observed that the LEBE deposited films have a rough colu mnar, crystalline structure and increased refractive index and laser d amage threshold values in comparison to amorphous films prepared by co nventional EBE.