The Study of Magnetic Properties of Fe-C-X(X=Sb,Ti,V) Thin Films

• Main Authors: Shinn-Ching Shyr, 石信卿
• Other Authors: Y.H.Chang
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/78625021643501720102

碩士 === 國立成功大學 === 材料科學(工程)研究所 === 82 === A planar magnetron sputtering system with cathode and anode cooled by water was established.Under 1700V and 50 mtorr argon working pressure ,high carbon contented Fe-C (C:50.1-75.5at%) and Fe-C-X(X=Sb,Ti,V)(C:54.3-79.5 at%, Fe:8.4-43.5at%, Sb:5.8-37.3at%,Ti:2.0-4.6at%,V:0.2-3.5 at%) ternary alloy films are produced.All films have island-like surface morphology under the observation of STM.As carbon content increases ,the structure changes from .alpha. iron to cementite and/or .kai. carbide(see appendix),when carbon content reaches 75.5 at%, no obvious X-ray diffraction peaks appear. The ternary alloys include two groups, one has cemen- tite and/or .kai. carbide, the other has microcrystalline kai carbide or near amorphous structure. All films have in-plane anisotropy. The magnetization at 14KOe applied field is 398.4-855.9emu/cc for Fe-C films and 94-680 emu/cc for Fe-C-X films, the quantity decreases as the composition moves towards higher carbon and/or alloying element content regions on ternary phase diagram. The coer- civity of Fe-C films increases with carbon content maybe owing to crystal anisotropy and internal stress in films. The in- plane coercivity is about 191.7-391.7 Oe for Fe-C binary and Ti or V contented ternary films. Sb contented films have higher coercivity up to 758.3 Oe,it maybe related to the higher inter- nal stress caused by Sb atoms because of larger atomic volume . For the sake of no perpendicular anisotropy, the squareness perpendicular to the film plane is about 0.03-0.211. The Kerr angle measured at 6328 angstrom wavelength is about 0.005-0.1 degree. The reflectance is about 0.5173-0.6764, which increases with carbon content at first and then decrease. The figure of merit is about 0.0039- 0.082 degree.