Title :
A new series of quaternary Co-alloys for high density rigid-disk applications
Author :
Lal, Brij B. ; Tsai, Hsiao-chu ; Eltoukhy, Atef
Author_Institution :
HMT Technol., Fremont, CA, USA
fDate :
11/1/1991 12:00:00 AM
Abstract :
Quaternary media CoCrPtTa(Q) with Hc up to 2400 Oe and Mrt greater than 1.3 memu/cm2 have been investigated for longitudinal magnetic recording. Magnetic properties and microstructure of the films were compared with CoCrTa(T) media. The coercivity decreases monotonically with temperature, and the magnetization has a very small dependence on temperature. The differential remanence measurements of Q and T media indicate fairly strong interactions among the crystallites. The Q media with 5-10% Pt exhibit 25-75% higher coercivity than the ternary media T with same atomic percentage of Cr and Ta. The media Q, containing 9.5% less Co produce the same remanence magnetization and slightly higher signal amplitudes. X-ray diffraction and transmission electron microscopy (TEM) data show larger grain-size and more grains with c-axis in-plane orientation in the Q media which can account for the higher coercivity
Keywords :
X-ray diffraction examination of materials; chromium alloys; cobalt alloys; coercive force; crystal microstructure; ferromagnetic properties of substances; grain size; hard discs; magnetic recording; magnetic thin films; magnetisation; platinum alloys; remanence; sputtered coatings; tantalum alloys; transmission electron microscope examination of materials; CoCrPtTa films; DC magnetron sputtering; TEM; X-ray diffraction; c-axis in-plane orientation; coercivity; crystallites; differential remanence measurements; grain-size; high density rigid-disk; longitudinal magnetic recording; magnetic properties; magnetization; microstructure; quaternary alloys; transmission electron microscopy; Coercive force; Crystallization; Magnetic films; Magnetic properties; Magnetic recording; Magnetization; Microstructure; Q measurement; Remanence; Temperature dependence;
Journal_Title :
Magnetics, IEEE Transactions on
