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Multilayered Thin films are effective in controlling the rate of corrosion of magnesium alloys used for bio-implants applications. It’s been proven that corrosion of metallic implants can be delayed by depositing multilayered metal-oxide thin films. In this study, Mg/Al2O3 nanolaminates, along with different metal oxides, were deposited using DC and pulsed DC magnetron sputtering methods at room temperature on glass substrates. Applicability of these metal-oxide nanolaminates to corrosion control was studied by bulk volumetric degradation measurement technique using solutions such as Saline, HANKS and PBS. Mg/Al2O3 films were also studied under different flow conditions by varying flow rates and pore growth rate and degradation process are measured by time-lapsed technique on optical microscope. Effect of the oxide layer thickness, saline flow rate, total pressure, structural characteristics of oxide coatings and sputtering deposition parameters on pore density and corrosion rate was investigated. Pulsed DC magnetron sputtering enables preparation of thin films with control over pore growth and distribution. Results have shown that repeatable pore density and corrosion rate can be achieved through magnetron sputter-deposited Mg/Al2O3 nanolaminates.

Thin films have always shown high sensitivity to its deposition parameters and surface morphology. Magnetron sputtering is known for its high level of consistency in deposition and repeatability. In this study Mg/Al2O3 nanolaminates in a range of 10 to 40 nm were synthesized using Direct current and Pulsed DC sputtering techniques at room temperature on glass substrates and silicon substrate using different oxygen flow rates and varying total pressure conditions to understand its effect on deposition rates and roughness of thin films. It is observed that more power and resources consumed for higher deposition time. Roughness of the film is very sensitive for certain applications like corrosion, Lenses, Implants. Scanning electron microscopy (SEM), Atomic force microscopy (AFM) were used to characterize the morphology, structure of the thin films. Optical microscopy and X-ray reflectometry (XRD-XRR) techniques confirmed the optical density and thickness of the nanolaminates respectively. It is confirmed that as total pressure and oxygen flow rate rises deposition rate significantly goes down, that impacts deposition time and roughness of thin films.