New longitudinal recording media CoxNiyCrzfrom high rate static magnetron sputtering system

Three new magnetic alloys A:Co64.2Ni27.4Cr8.4. B:Co74.1Ni15.9Cr10.0, and C:Co82Ni18were used as targets to sputter thin films with coercivities up to 1015 Oe, 926 Oe, and 825 Oe respectively. Chromium films were used as the base layer. With a base pressure below 2 × 10^-7torr and chromium thickness of 2500Å, the following magnetic characteristics of alloys A and B were obtained: Hc>900 Oe, Brδ>530 G-µm, S>78%, S* > 93%, S/N (at 5MHz) > 45dB and D50> 17KBPI. X-ray diffraction measurements indicate the (1011) texture of CoNiCr films is the reason for the high coercivity and squareness ratio. This orientation may result because the in-plane atom density for Co alloys HCP(1011) and Cr BCC