New longitudinal recording media CoxNiyCrzfrom high rate static magnetron sputtering system

Three new magnetic alloys A:Co
64.2
Ni
27.4
Cr
8.4
. B:Co
74.1
Ni
15.9
Cr
10.0
, and C:Co
82
Ni
18
were 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
^-7
torr and chromium thickness of 2500Å, the following magnetic characteristics of alloys A and B were obtained: H
c
>900 Oe, B
r
δ>530 G-µm, S>78%, S* > 93%, S/N (at 5MHz) > 45dB and D
50
> 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