Title :
Increase of coercivity and squareness ratio of by ferrite thin films by adding SiO2 and substituting Al for Fe
Author :
Feng, J. ; Funabashi, N. ; Matsushita, N. ; Nakagawa, S. ; Naoe, M.
Author_Institution :
Dept. of Phys. Electron., Tokyo Inst. of Technol., Japan
fDate :
9/1/2000 12:00:00 AM
Abstract :
Simple Ba ferrite (BaM) and SiO2-added BaM (BaM:SiO2) and Al substituted BaM (Al-BaM) films were deposited using the facing targets sputtering apparatus on SiOx /Si wafers with Pt seed layers to enhance the c-axis orientation perpendicular to the film plane. Magnetic characteristics of the three kinds of BaM films were investigated and compared. Perpendicular coercivity Hc⊥ and squareness ratio S⊥ of BaM:SiO2 films increased to 4.2 kOe and 0.83, respectively, Hc⊥ and S⊥ of Al-BaM films increased to 3.2 kOe and 0.89, but saturation magnetization Ms decreased to 2.9 kc. The magnetization reversal mechanism of BaM:SiO2 and BaM films is not in coherent rotation mode but seems to be in the curling mode. The reason for high Hc⊥ of BaM:SiO2 films is different from that of Al-BaM ones
Keywords :
barium compounds; coercive force; ferrites; magnetic thin films; magnetisation reversal; silicon compounds; sputtered coatings; 2.9 kG; Al; Ba ferrite; Ba(FeAl)2O4:SiO2; Pt; Pt seed layers; Si; SiO; SiO2; SiOx/Si wafers; c-axis orientation; coercivity; curling mode; facing targets sputtering apparatus; ferrite thin films; magnetization reversal mechanism; perpendicular coercivity; saturation magnetization; squareness ratio; Annealing; Coercive force; Crystallization; Ferrite films; Magnetic films; Magnetization reversal; Perpendicular magnetic recording; Saturation magnetization; Semiconductor films; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
