An inverted gapped-target sputter magnetron for the deposition of thin ferromagnetic films

An inverted gapped-target magnetron sputtering device has been developed for deposition of ferromagnetic thin films under energetic conditions. The main feature of this technique is that the discharge is driven by a positive voltage relative to a grounded target situated away from the magnetic field. As a result, it is possible to efficiently sputter ferromagnetic materials and have a source of energetic plasma ions available in the ion-assisted deposition process at the substrate. Electrical probe measurements have shown that the density and the most likely energy of the ions arriving to the grounded substrate is approximately 1016 m−3 and 200 eV, respectively. In the sputtering of nickel films, no cracking of the film surfaces was observed, without substrate heating or biasing. The energetic ions available with this inverted configuration are thought to be the main contributor to the observed enhancement in overall film qualities