2018 Volume 61 Issue 7 Pages 469-473
To improve the surface flatness, impact and corrosion resistance of magnetic recording media, low–pressure (0.6 Pa) deposition of CoPtCr–SiO2 granular films by Ar＋O2 reactive sputtering using a Co65Pt14Cr9Si12 target was investigated. It was found that as the fraction of oxygen in the sputtering gas flow (FO2) was increased from 0 to 20%, the deposition rate increased from 2.8 to 4.3 nm/s, and then decreased to 1.1 nm/s as FO2 was further increased. For FO2＝10–12%, the designed composition with the desired oxygen content (Co74Pt16Cr10–8 mol%SiO2) could be achieved. For FO2＝8%, while a flat surface granular film with c-plane oriented CoPtCr grains was realized, a slight amount of Si remaining in magnetic grains which indicated the insufficient segregation of SiO2 into the grain boundaries was observed.