Effects of additive gases on properties of Co-Cr film media during high rate sputtering.

Abstract

The effects of H₂, O₂ and N₂ additives on the magnetic properties of Co-Cr film were studied for high rate sputtering. O₂ and N₂ react with Co-Cr to from compounds. N₂ addition induces fcc orientation perpendicular to the film plane, and hence causes a drastic decrease of the perpendicular anisotropy field H_k, accompanied by hcp orientation degradation. O₂ is most reactive to Co-Cr, but little affects the crystal structure. These effects become less at higher deposition rate for the same introduced pressure. In contrast, H₂ does not react with Co-Cr at all, but has a unique role of changing the coercive force without any change of H_k or crystal orientation. The effects of N₂ and H₂ are concluded respectively equivalent to that of increase and decrease of substrate temperature.