[en] Hafnium-oxide (HfO_2)-based materials have been extensively researched due to their excellent optical and electrical properties. However, the literature data on the mechanical properties of these materials and its preparation for heavy machinery application is very limited. The aim of this work is to deposit hafnium oxide thin films by DC reactive magnetron sputtering with different Young’s Modulus from the Ar/O_2 concentration variation in the deposition chamber. The thin films were deposited by DC reactive magnetron sputtering with different Ar/O_2 gas concentrations in plasma. After deposition, HfO_x thin films were characterized through XRD, AFM, RBS and XRF. In this regard, it was observed that the as-deposited HfO_2 films were mostly amorphous in the lower Ar/O_2 gas ratio and transformed to polycrystalline with monoclinic structure as the Ar/O_2 gas ratios grows. RBS technique shows good compromise between the experimental data and the simulated ones. It was possible to tailored the Young Modulus of the films by alter the Ar/O_2 content on the deposition chamber without thermal treatment.