Structure and properties of Al2O3 thin films deposited by ALD process

• Al2O3 films was deposited by ALD method in temperature 150, 225 and 300 °C.
• Combined SEM, AES and ToF-SIMS studies confirmed chemical composition of the layers.
• The best properties exhibits the layer deposited at 300 °C.

The comprehensive investigation results of the microstructure, mechanical properties and corrosion resistance of the Al2O3 thin films deposited on hot work tool steel substrate are presented in the paper. Aluminium oxide layers were prepared using atomic layer deposition (ALD) method in temperature 150, 225 and 300 °C.The uniform structure of the investigated coatings without any visible delamination was observed as a result of measurements performed with the use of scanning electron microscope. Combined SEM, AES and ToF-SIMS studies confirmed presumed chemical composition of the layers. Despite the very low thickness (∼200 nm) the layers demonstrated an excellent adhesion to the substrate, as well as a high hardness and corrosion resistance. The best mechanical properties and corrosion resistance exhibit the layers deposited at 300 °C.The excellent properties of the ALD thin films make them suitable for various engineering and industrial applications.