Title :
Fabrication and study of Ni75Fe25-SiO2 granular films for high frequency application
Author :
Ge, Shihui ; Yang, Xiaolin ; Kim, Kwang Youn ; Xi, Li ; Kou, Xiaoming ; Yao, Dongsheng ; Li, Binsheng ; Wang, Xinwei
Author_Institution :
Key Lab. for magnetism & Magnetic Mater. of Ministry of Educ., Lanzhou Univ., China
Abstract :
Ni75Fe25-SiO2 granular films are fabricated and studied for high frequency applications. The films of different metal volume fraction fv are fabricated by magnetron co-sputtering and they have fcc Ni3Fe structure determined by X-ray diffraction. Magnetic hysteresis loops show that the samples of fv=0.81 have in plane uniaxial anisotropy. The resistivity ρ is shown to increase slowly with decreasing fv then increases rapidly after fv>0.7, while coercivity Hc decreases rapidly as fv decreases from 0.81 to 0.52 and does not exceed 5 Oe. In this fv range, good soft magnetic properties are obtained especially for the sample with fv=0.52 in which ρ reaches 19000 μΩ·cm with negative temperature coefficient. This high ρ effectively depresses the eddy current loss as applying for high frequency range. These interesting behavior is understood by exchange coupling between nanoparticles.
Keywords :
X-ray diffraction; coercive force; eddy current losses; electrical resistivity; exchange interactions (electron); ferromagnetic materials; granular materials; iron alloys; magnetic anisotropy; magnetic hysteresis; magnetic particles; magnetic thin films; nanoparticles; nickel alloys; silicon compounds; soft magnetic materials; sputter deposition; sputtered coatings; 19000 muohmcm; Ni75Fe25-SiO2; X-ray diffraction; coercivity; eddy current loss; exchange coupling; granular films; high frequency range; in plane uniaxial anisotropy; magnetic hysteresis loops; magnetron co-sputtering; metal volume fraction; negative temperature coefficient; resistivity; Anisotropic magnetoresistance; Fabrication; Frequency; Iron; Magnetic anisotropy; Magnetic films; Magnetic hysteresis; Perpendicular magnetic anisotropy; Soft magnetic materials; X-ray diffraction;
Conference_Titel :
Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International
Print_ISBN :
0-7803-9009-1
DOI :
10.1109/INTMAG.2005.1463940