Title :
Co/Pt superlattices with ultra-thin Ta seed layer on NiFe underlayer for double-layer perpendicular magnetic recording media
Author :
Peng, Wenbin ; Keitel, Oliver ; Victoria, R.H. ; Koparal, Erkan ; Judy, Jack H.
Author_Institution :
Dept. of Electr. & Comput. Eng., Minnesota Univ., Minneapolis, MN, USA
fDate :
9/1/2000 12:00:00 AM
Abstract :
Co/Pt superlattices with an ultra-thin amorphous Ta seed layer on a Ni45Fe55 underlayer were fabricated for double-layer perpendicular magnetic recording media using a special hard disk sputtering system with a triple-target DC magnetron cathode (Triatron). A 2.5 nm thick Ta seed layer was found to improve the crystalline structure and increase the coercivity of the Co/Pt superlattices from 1.13 to 2.17 kOe. A 2.5 nm Ta layer on a 200 nm thick magnetically soft NiFe underlayer was found to further increase the coercivity from 2.25 to 5 kOe. In addition, the sheared slope of the sides of hysteresis loop of Co/Pt superlattices was significantly improved from about 5 Gauss/Oe (with only a 2.5 nm Ta seed layer) to about 1.1 Gauss/Oe (with both a 2.5 nm Ta seed layer and a 200 nm NiFe underlayer)
Keywords :
cobalt; coercive force; iron alloys; magnetic hysteresis; magnetic multilayers; metallic superlattices; nickel alloys; perpendicular magnetic recording; platinum; sputter deposition; tantalum; Co; Co/Pt superlattices; Ni45Fe55; NiFe; NiFe underlayer; Pt; Ta; Triatron; coercivity; crystalline structure; double-layer perpendicular magnetic recording media; hard disk sputtering system; hysteresis loop; magnetically soft NiFe underlayer; triple-target DC magnetron cathode; ultrathin Ta seed layer; Amorphous magnetic materials; Amorphous materials; Cathodes; Coercive force; Gaussian processes; Hard disks; Iron; Magnetic superlattices; Perpendicular magnetic recording; Sputtering;
Journal_Title :
Magnetics, IEEE Transactions on
