Characterization of Aluminum Oxide Films Deposited on Al2O3-TiC by RF Diode Sputtering

AbstractIn magnetic head recording storage, Al2O3 film was deposited onto Al2O3-TiC substrate, as insulating and protection layers, using RF diode sputtering. Pure Al2O3 (99.5%) with a dimension of 43.2cm × 43.2cm × 2.0cm was used as a sputtering target. The base pressure for all depositions was 1 × 10-6 m Torr and the deposition time was 12.2min. The target sputtering power and substrate bias voltage were varied from 4 to 8kW and 80 to 180V, respectively. The surface morphology of Al2O3 films was investigated using atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was found that the roughness of deposited Al2O3 films depends on sputtering power. SEM cross-sectional image clearly showed good adhesion between substrate and Al2O3 film. The mechanical properties, including elastic modulus and hardness, of Al2O3 films were performed on nanoindentator. The results showed that both elastic and hardness of Al2O3 films increased with the increase of target sputtering power