Role of oxygen incorporation in Co-Cr-Pt-Si-O perpendicular magnetic recording media

The effect of oxygen incorporation on the crystallographic, magnetic, and recording performance of perpendicular magnetic recording (PMR) oxide media was investigated. The media were prepared by dc-magnetron sputtering of CoCrPt-SiO/sub 2/ targets in an Ar/O/sub 2/ gas mixture. X-ray photoelectron spectroscopy (XPS) detected Cr-O peaks in the sputtered film, whereas no strong evidence of SiO/sub 2/ is seen. Moderate oxygen incorporation in the film (/spl sim/15 at%) promotes Cr-O formation in the grain boundary and results in a dramatic increase of coercivity H/sub c/ and signal-to-noise ratio (SNR). However, as the O/sub 2/ content is further increased, oxide incorporates into the core of the grains, resulting in decreased H/sub c/, magnetization and SNR.