Deposition of thin films by sputtering cold isostatically pressed powder targets: A case study



Powders of copper and aluminium with a maximum grain size of 50 µm are mixed in different ratios. The mixtures are cold isostatically pressed into two-inch circular targets which are mounted in a conventional magnetron set-up and used to deposit both metallic Cu–Al as well as oxygen rich Cu–Al–O thin films. In both cases the thin film composition is analysed and related to the target composition. Crystallographic properties of the deposited films are presented as well. The influence of the target composition on the reactive behaviour is studied by hysteresis measurements. Furthermore, the effective sputter yields of elemental powder targets were measured. Depending on the material, the sputter yields of the powder target either increased or decreased compared to the sputter yields of solid targets. This can be qualitatively explained by an analysis of the target roughness. For the fast scanning of the compositional influence on material properties, the use of powder targets shows to be a suitable and valuable approach.