Composition, structure and optical properties of aluminum nitride films formed by low energy ion beam assisted deposition

Thin films of aluminum nitride are of interest for a variety of applications in different fields, including optoelectronics, microelectronics, surface acoustic wave devices, and tribology. This is due to its favourable features such as high electrical resistivity, high thermal conductivity, wide band gap, high ultrasonic velocity, high hardness, high melting point and chemical inertness. Owing to its excellent controllability and reproducibility, ion beam assisted deposition is favourable technique for depositing AlN. In the present contribution, results on properties of AlN films formed by condensation of aluminum metal under concurrent bombardment with nitrogen ions with low energy on substrates of silicon and fused quartz at elevated temperature are presented. The films become stoichiometric in their composition when the ion-to-atom arrival ratio exceeds 1.3, These films exhibit a c-axis orientation in growth direction. They are highly optical transparent and electrically nonconductive.