DESCRIPTION OF TRANSFER AND DEPOSITION DURING PLD OF THIN CERAMIC FILMS

Thin films of ceramic materials (Al2O3, ZrO2) for technical applications are deposited at different laser parameters (wavelength, fluence, mode of operation) and processing variables (processing gas pressure and composition, rf bias, distance target-substrate). The material transfer is studied by high-speed photography and emission spectroscopy as a function of laser parameters and processing variables. Time-resolved (0.01-10 mus after the beginning of the laser pulse) measurements of the geometry, dynamics, velocity of the vapour/plasma front (max. v = 60 000 m/s), composition, ionization state and electron-temperature (40 000-140 000 K) are obtained. The morphology, structure and composition of the films are investigated by SEM, XRD and EDX. The deposited films show a broad variety of different structures which correspond to sputtered films on heated substrates. The results are discussed in view of applications. The overall view of experimental results allows the description of the material transfer which is related to the properties of the thin films deposited.