Tribological Properties of Alumina Films Fabricated by Atomic Layer Deposition

Alumina films were deposited on silicon substrates at different temperatures using atomic layer deposition. The morphology of the as-prepared film was observed on an atomic force microscope. The hardness and Young's modulus of the films were measured with a nano-indenter. The influence of friction loading and the species of counterpart ball on the tribological properties of alumina films deposited at different temperature were systematically investigated on a UMT-2 tribometer. The results indicate that the alumina films deposited at 100 ℃ and 200 ℃ were smoother with low roughness as compared with the films deposited at 50 ℃ and 300 ℃. It was further detected that the sample with a lower roughness had a lower friction coefficient.The sample tested under applied loads of 50 mN and 80 mN was characterized by a lower friction coefficient as compared with the sample tested under 30 mN and 100 mN. Due to different hardness of the counterpart balls, different wear phenomena were observed on the worn surfaces.