Mechanical properties of Al/Al2O3 nanolaminated films: correlation to microstructure

Abstract Wear resistance and the hardness of Al/Al 2 O 3 nanolaminated films were investigated in this study. Monolithic films and multilayers were deposited on a silicon substrate with two different substrate temperatures: T s =25°C and T s =−90°C. The period thickness of multilayers was lowering from 40 to 2 nm. From nanoindentation measurements, it appears that the hardness of multilayers has an intermediate value between those of metal (Al) and ceramic (Al 2 O 3 ). The tribological test was conducted by the pin-on-disc method. The T s =25°C deposited multilayers, as well as single films, demonstrated poor wear resistance. The best wear resistance was obtained for multilayers deposited at the lowest substrate temperature ( T s =−90°C). The results are in good agreement with structural characterization. X-ray reflectometry demonstrated that the multilayer character of Al/Al 2 O 3 is more pronounced for T s =−90°C.