High temperature magnetic properties of Fe{sub 81-x}Co{sub x}Ga{sub 19}/Si(100) films

Journal Article · Fri Apr 01 00:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3560120· OSTI ID:21560151

Tsai, T L ^[1]; Jen, S U ^[2]; Kuo, P C ^[1]

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1. Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan 10617 (China)
2. Institute of Physics, Academia Sinica, Taipei, Taiwan 11529 (China)

Fe{sub 81-x}Co{sub x}Ga{sub 19} (with x ranging from 0 to 19 at.% Co) films with thicknesses of about 110 nm were deposited on Si(100) substrates by the dc magnetron sputtering method. The structures of these films at room temperature (RT) were analyzed by x-ray diffraction. Magnetic hysteresis loops of each film were measured from room temperature (RT) to 800 deg. C, and their saturation magnetization (4{pi}M{sub S}) and coercivity (H{sub C}) were plotted as a function of temperature (T). Saturation magnetostriction ({lambda}{sub S}) at RT was also measured. The substitution of Co for Fe would give rise to increases in H{sub C} and {lambda}{sub S}. In terms of high temperature magnetic properties, (A) we find that for each film, there is one low-temperature-phase Curie point (T{sub C1}) and one high-temperature-phase Curie point (T{sub C2}); (B) based on the temperature dependence of 4{pi}M{sub S}, we calculated the reduced hyperbolic Bessel function I{sub 5/2}(T); from the relationship {lambda}{sub S}(T)=I{sub 5/2}(T)x{lambda}{sub S}(RT), we can compare the performances of {lambda}{sub S}(T) at higher temperatures; and (C) H{sub C} decreases slightly as T increases initially, but it reaches a maximum when either T{sub C1} or T{sub C2} is approached. It is concluded that the Fe{sub 62}Co{sub 19}Ga{sub 19} film has the optimal high-temperature magnetic properties, including a larger {lambda}{sub S}(T), higher T{sub C1}, and moderate H{sub C}(T).

• OSTI ID: 21560151
• Journal Information: Journal of Applied Physics, Vol. 109, Issue 7; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: DOI: 10.1063/1.3560120; (c) 2011 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BESSEL FUNCTIONS
COBALT ALLOYS
COERCIVE FORCE
CURIE POINT
DEPOSITION
GALLIUM ALLOYS
HYSTERESIS
IRON ALLOYS
MAGNETIZATION
MAGNETOSTRICTION
MAGNETRONS
SATURATION
SILICON
SUBSTRATES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
X-RAY DIFFRACTION
ALLOYS
COHERENT SCATTERING
DIFFRACTION
ELECTRON TUBES
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
FILMS
FUNCTIONS
MAGNETIC PROPERTIES
MICROWAVE EQUIPMENT
MICROWAVE TUBES
PHYSICAL PROPERTIES
SCATTERING
SEMIMETALS
TEMPERATURE RANGE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT ALLOYS
TRANSITION TEMPERATURE