Title :
Magnetostriction of Tb-Fe-(B) thin films fabricated by RF magnetron sputtering
Author :
Lim, S.H. ; Choi, Y.S. ; Han, S.H. ; Kim, H.J. ; Shima, T. ; Fujimori, H.
Author_Institution :
Magnetic Mater. Lab., Korea Inst. of Sci. & Technol., Seoul, South Korea
fDate :
9/1/1997 12:00:00 AM
Abstract :
The magnetostriction of TbFe and TbFeB thin films is systematically investigated over a wide composition range from 40.2 to 68.1 at.% Tb for the B-free alloys and from 44.1 to 66.8 at.% Tb for the B containing thin films. The films were fabricated by rf magnetron sputtering. The microstructure mainly consists of an amorphous phase at low Tb contents and, at high Tb contents, a mixture of an amorphous phase and an α Tb phase. Excellent magnetostrictive characteristics, particularly at low magnetic fields, are achieved in both TbFe and TbFeB thin films; for example, a magnetostriction of 138 ppm is obtained in a TbFeB thin film at a magnetic field as low as 30 Oe. These excellent magnetostrictive properties of the present thin films are supported by the excellent magnetic softness, the coercivity below 10 Oe and a typical squared-loop shape with the saturation field as low as 1 kOe. It is considered that, due to the excellent low field magnetostrictive characteristics, the present TbFe based magnetostrictive thin films are suitable for Si based microdevices
Keywords :
amorphous magnetic materials; boron alloys; coercive force; iron alloys; magnetic thin films; magnetostriction; soft magnetic materials; sputtered coatings; terbium alloys; α Tb phase; RF magnetron sputtering; TbFe; TbFeB; amorphous phase; coercivity; magnetic softness; magnetostriction; microdevices; microstructure; thin films; Amorphous magnetic materials; Amorphous materials; Magnetic fields; Magnetic films; Magnetostriction; Microstructure; Radio frequency; Saturation magnetization; Sputtering; Transistors;
Journal_Title :
Magnetics, IEEE Transactions on