Properties of physically deposited thin aluminium film coatings: A review

Aluminium thin films exhibit excellent coating properties suitable for optical, microelectronics, telecommunications and constructional/structural applications. Thin aluminium film deposition is mainly accomplished via physical or chemical methods at varying deposition conditions, parameters and substrates. This study focuses on thin aluminium films prepared using physical methods which have superior properties to chemical methods and are extensively researched in the published literature. The review discusses the properties of thin aluminium films and their complex interactions with process parameters. The properties of thin films depend on the deposition parameters which include substrate temperature, deposition rate, power, process pressure, substrate surface finish, and target temperature. Post-deposition treatment of the films and the type of substrate also influence the properties of thin films. This review therefore highlights the significance of optimising the deposition methods and identifies research gaps in the published studies. The work can be a primary resource for selection of essential process parameters during physical deposition aluminium films.