Properties of hafnium and aluminium silicates coatings obtained by PLD

Abstract

We report on the deposition and characterization of hafnium silicate and aluminium silicate thin films for different applications in optics and electronics. Pulsed laser deposition in a controllable oxygen atmosphere was used as a processing technique, with optimized parameters in terms of laser wavelength, laser fluence and oxygen pressure. The thin films were investigated using atomic force microscopy, spectroscopic ellipsometry, UV–VIS spectroscopy and X-ray photoelectron spectroscopy. The morphological investigations evidenced uniform layers with low roughness (in the order of nanometres). The optical investigations revealed that aluminium silicate layers with low roughness and low absorption in the infrared (IR) range can be obtained at high substrate temperatures (600◦C). The behaviour of the silicate thin films with respect to the nanosecond IR laser irradiation revealed that aluminium silicate layers have higher laser-induced damage threshold values in comparison with hafnium silicate.