CoPtCr composite magnetic thin films

CoPtCr composite thin films were produced by cosputtering nonmagnetic compounds such as SiO₂, SiN, ZrO₂, and SiC. These films were prepared without using any underlayer. It was found that the magnetic properties of CoPtCr alloys, such as the in-plane coercivity H_c and coercivity squareness S*, were significantly improved by admixing nonmagnetic compounds. CoPtCr+SiO₂ (10 vol.%) composite films were obtained showing a high coercivity of more than 2 kOe for a thickness of 25 nm, without using an underlayer. Torque magnetometer and X-ray pole figure measurements revealed that, when SiO₂ is admixed, the c-axis of CoPtCr films tends to decline toward the in-plane direction, as a result of the increase of the in-plane anisotropy. From the experimental results of magnetic recording, it was found that the media noise of CoPtCr films was reduced by admixing SiO₂