Title :
Perpendicular magnetic recording media based on Co-Pd multilayer with granular seed layer
Author :
Matsunuma, Satoshi ; Yano, Akira ; Fujita, Enji ; Onuma, Tsuyoshi ; Takayama, Takanobu ; Ota, Norio
Author_Institution :
Dev. & Technol. Div., Hitachi Maxell Ltd., Ibaraki, Japan
fDate :
7/1/2002 12:00:00 AM
Abstract :
We have investigated Co-Pd multilayers deposited on a Pd-SiN granular seed layer and a FeTaC soft magnetic underlayer (SUL) for perpendicular magnetic recording. The Pd-SiN granular seed layer of 3 nm was found to be very effective for good magnetic properties with coercivity of 3.9 kOe, a negative nucleation field of -2.1 kOe, and a M-H loop slope parameter 4π (dM/dH)H=Hc of 1.3. The average column diameter of 13.7 nm with a dispersion of 21.7% was evaluated from the transmission electron microscopy image of well-separated columns with a clear boundary. This Co-Pd medium gave better playback performances by a merged ring giant magnetoresistive head compared to the medium with a Pd seed layer. The effect of Ar plasma etching on the SUL was also investigated to improve playback performance
Keywords :
cobalt; coercive force; giant magnetoresistance; granular structure; magnetic heads; magnetic multilayers; magnetoresistive devices; palladium; perpendicular magnetic recording; plasma materials processing; silicon compounds; sputter etching; transmission electron microscopy; 3 nm; Ar plasma etching; Co-Pd; Co-Pd multilayer; FeTaC; FeTaC SUL; FeTaC soft magnetic underlayer; M-H loop slope parameter; Pd seed layer; Pd-SiN; Pd-SiN granular seed layer; average column diameter; coercivity; dispersion; magnetic properties; merged ring giant magnetoresistive head; negative nucleation field; perpendicular magnetic recording media; playback performances; transmission electron microscopy image; Argon; Coercive force; Giant magnetoresistance; Magnetic heads; Magnetic multilayers; Magnetic properties; Perpendicular magnetic recording; Plasma applications; Soft magnetic materials; Transmission electron microscopy;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2002.1017745
