Anodic aluminum oxide (AAO) is widely used in various industrial fields to increase the mechanical property or corrosion resistance of the product surface. In this study, mechanical properties were measured according to the thickness of AAO through the nanoindentation test. The maximum indentation load, elastic modulus, and hardness were measured for different thicknesses of AAO. It was confirmed that the majority of the mechanical property values increased with the thickness. Various fracture shapes based on the thickness were analyzed by observing pressure marks on the surface using FE-SEM equipment. Apparently, it is proposed that the optimum AAO thickness with desired mechanical properties can be obtained, which is expected to possess immense economic value as per the optimization of the production time of AAO based products.

Picosecond ultrasonic evaluation on the Young’s modulus of a ceramic thin-film was performed in the present study. A 100nm thick silicon nitride thin-film was deposited on a silicon wafer using the plasma enhanced chemical vapor deposition technique and gigahertz-frequency longitudinal bulk waves were excited in the film using a femtosecond laser setup. A thermoelastic equation was numerically solved using the finite difference method and compared to the experimental data to estimate the elastic property of the film. Results show that the present measurement technique can effectively evaluate the film’s Young’s modulus and it is recognized that the modulus is 60-70% lower than that of its bulk status. This study is expected to provide a way to characterize nanoscale ceramics with very high spatial and temporal resolutions for the design and analysis of microelectromechanical systems and thin-film based devices.