Title :
High-Bs low-Hc CoNiFe films with bcc single-phase structure for write heads
Author :
Okada, Yasuyuki ; Kudo, Kazue ; Yoshida, Nobuo ; Fuyama, Moriaki ; Hoshiya, Hiroyuki
Author_Institution :
Central Res. Lab., Hitachi Ltd., Kanagawa, Japan
fDate :
9/1/2002 12:00:00 AM
Abstract :
We studied electroplated CoNiFe films with a bcc structure and large magnetic flux density (Bs), and by changing the film composition obtained various surfaces and magnetic properties for such films. Films plated under conventional conditions have a high Bs of 2.0 T and large coercivity (Hc) of 30 Oe, which are caused by the large grain size in the bcc structure. We found that by plating the films with high current density, the grain size decreased and as a result, low Hc of 15 Oe is obtained while preserving high Bs. Recording heads fabricated with such bcc-CoNiFe film show good overwrite performance.
Keywords :
cobalt alloys; coercive force; electroplated coatings; ferromagnetic materials; grain size; iron alloys; magnetic heads; magnetic thin films; nickel alloys; soft magnetic materials; BCC single-phase structure; CoNiFe; CoNiFe film; chemical composition; coercivity; crystal growth; current density; electroplating process; grain size; magnetic recording; overwrite characteristics; saturation magnetic flux density; soft magnetic material; soft magnetic properties; surface morphology; write head; Coercive force; Crystalline materials; Grain size; Magnetic films; Magnetic flux density; Magnetic heads; Magnetic materials; Magnetic properties; Magnetic recording; Soft magnetic materials;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2002.802779
