Title :
Magnetic properties of Fe/Ti multilayered films for a magnetic recording medium
Author :
Ono, Satoshi ; Nitta, Michio ; Naoe, Masahiko
Author_Institution :
Dept. of Phys. Electron., Tokyo Inst. of Technol., Japan
fDate :
9/1/1989 12:00:00 AM
Abstract :
Films with combinations of Fe and Ti layers of various thicknesses (dFe of 10~1000 Å and dTi of 10~200 Å) have been prepared at Ar gas pressure of 2 mtorr in an apparatus with two pairs of facing-target sputtering sources. The total thickness of the Fe layers was fixed at 1000 Å for all specimen films. The saturation magnetization 4πMs calculated from the expected total thickness of Fe layers decreased first gradually and then abruptly with dFe, becoming almost zero at dFe of about 15 Å for all as-deposited films. The coercive force, Hc, increased with decreasing dFe, taking a maximum value of 270 Oe at dFe of 20 Å, and decreased abruptly with further decrease of dFe. The films with modulation period of Fe(52 Å)/Ti(53 Å) which were annealed at temperatures above 200°C had smaller 4 πM than the as-deposited ones and Hc as high as 650 Oe at 230~325°C. Films with this modulation period annealed at about 250°C could be used as a magnetic recording medium because they have relatively large average 4πMs of 4 kG, H c of 650 Oe, moderate squareness of 0.7, and coercivity squareness of 0.8
Keywords :
coercive force; iron; magnetic recording; magnetic thin films; magnetisation; sputtered coatings; titanium; Fe-Ti multilayer films; coercive force; coercivity squareness; facing-target sputtering sources; magnetic recording medium; modulation period; saturation magnetisation; Annealing; Argon; Coercive force; Iron; Magnetic films; Magnetic modulators; Magnetic properties; Saturation magnetization; Sputtering; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on