Filmes cerâmico-metálicos nanoestruturados produzidos por magnetron sputtering

Abstract

This work deals with the deposition of nanostructured ceramic-metallic thin films made by magnetron sputtering. Three groups (Ti-Si-C-N, Al-Ti-C and Al-Si-N) were deposited from a mixture of metallic and ceramic sputtering targets (Ti and SiC2, Ai and TiC, and AI and Si3N4, respectively). Ti-Si-O-N films were deposited seeking an application on solar collector systems; Al-Ti-C group was designed aiming an application on mirrors for heliostats used on solar concentrating systems; and Al-Si-N films were deposited seeking the hardnening of AI films. Deposited films were analyzed by transmission electron microscopy to evaluate its morphology. X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectrometry (RBS) were used to determine the films chemical composition. The nanohardness of Al-Ti-C and Al-Si-N groups was evaluated, while samples from Ti-Si-C-N group were optically analyzed on ultraviolet, visible and infrared radiation ranges. Analyses results show that films from every group are formed by metallic nanocrystals embedded in an amorphous matrix, where both the volumetric fraction of nanocrystals and films hardness are dependent on the amount of deposited metal. Films from Ti-Si-C-N group showed nanoparticles only on the high metal fraction layer, linked to the thermal emittance of samples; the low metal fraction layer, related to solar absorption, did not show metallic nanoparticles.