Preparation of CoTbFeAg and CoTbFe/Ag thermo-magnetic recording media

• Main Authors: Nai-Wen Cheng, 鄭乃文
• Other Authors: 郭博成
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/61775432950881381134

碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 91 === Abstract In this study, CoTbFeAg alloy films with thickness of 500 Å and CoTbFe(500 Å)/Ag(0~1000 Å)were both deposited on nature oxidized Si(100) substrates at room temperature by DC magnetron sputtering. The alloy film was sandwiched between two 300 Å SiNx protective layers which were prepared by RF magnetron sputtering to prevent the alloy film from oxidation. The effect of sputtering condition on the alloy film composition and the magnetic properties were investigated. From XRD and TEM analysis, the structure of the as-deposited-film Co58.94-zTb19.05Fe22.01Agz was amorphous state as z=0~18.51 at.﹪. The increase of non-magnetic element, Ag , content would rise both the saturation magnetization Ms and perpendicular remanent magnetization Mr⊥ of CoTbFeAg alloy film, and the magnetic anisotropy of the CoTbFeAg film was perpendicular to the film plane. The thermomagnetic analysis shown that Curie temperature Tc of the Co58.94-zTb19.05Fe22.01Agz film was in the range from 237℃ to 166℃ as z=0~18.51 at.﹪. The increase of Ag content would decrease the Curie temperature Tc of the CoTbFeAg alloy film. The perpendicular coercivity Hc⊥of the Co55.75Tb19.05Fe22.01Ag3.19 film was 2058 Oe, Mr⊥ was 251 emu/cm3 and perpendicular squareness S⊥equal to 0.937. The film is suitable for thermomagnetic recording media applications. On the other hand , to increase an Ag underlayer would rise the perpendicular coercivity Hc⊥ of the Co58.94Tb19.05Fe22.01 film .The perpendicular coercivity Hc⊥of the Co58.94Tb19.05Fe22.01（500Å）/Ag（500Å） film was 3176 Oe, Mr⊥ was 195 emu/cm3 and perpendicular squareness S⊥equal to 0.990. The film is also suitable for thermomagnetic recording media applications.