Physico-Chemical and Mechanical Properties of DC-Sputtered ZrO2 Coatings Prepared by Oblique Angle Deposition

Abstract

In this study, a ZrO2 thin film was deposited onto a Ti6Al4V substrate using the Oblique Angle Deposition (OAD) technique. The influence of the substrate/Zr target an-gle (15°, 30°, 45°, and 60°) was investigated, with a fixed azimuthal orientation (Phi) of 180°. The primary objective of this work is to develop and characterize novel biocompatible coat-ings for hip prosthesis implants with a complex 3D spherical geometry. The OAD method enables thin film deposition on such geometries and enhances understanding of how the par-ticle incidence angle affects the surface morphology and microstructure of zirconium oxide (ZrO2) thin films. This study combines an experimental approach DC magnetron sputtering with a multi-scale numerical approach using Monte Carlo codes (SRIM, SIMTRA, and NASCAM). The structure, texture, and growth of the ZrO2 coatings were analyzed via X-ray diffraction (XRD), while microstructure and surface morphology were examined using scan-ning electron microscopy (SEM). Hardness and Young’s modulus were determined through nanoindentation testing. Results indicate that increasing the oblique angle leads to a decrease in hardness. Experimental and numerical findings complement each other, offering deeper insight into the deposition phenomena. SIMTRA simulations closely replicate experimental observations: a higher number of incident particles results in increased coating thickness. Additionally, the film thickness decreases with increasing substrate inclination angle. The microstructure of ZrO₂ thin films is strongly influenced by substrate orientation, and coated substrates demonstrate superior performance compared to their uncoated counterparts.