Rapid production of highly coercive Sm-Co thin films by triode sputtering

The rapid production of magnetically hard thin films over large surface areas is of interest for the integration of high performance materials into micro and nano systems. Compared to conventional magnetron sputtering, characterized by typical deposition rates of 0.1nm/s, much higher rates (5.5nm/s) can be achieved with triode sputtering. The latter was already used to produce magnetically hard thick films (5 μm) of Sm-Co with in plane texture and coercivities up to 2T. For certain applications, there is interest to decrease the film thickness while maintaining the good magnetic properties. In this study, we report on the triode sputtering of Sm-Co films with thickness of 100nm. The influence of deposition temperature and Sm concentration on the film's magnetic and microstructural properties has been studied. Room temperature coercivity up to 5T has been achieved for 100nm thick films deposited cold and annealed at 450°C for 10min. Grazing incidence XRD measurements showed these films to have the Sm₂Co₇ structure.