Magnetic Properties and Microstructures of Granular FePtCr-SiNx Thin Films

• Main Authors: Chen-Chieh Chiang, 蔣振劼
• Other Authors: P. C. Kuo
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/01230469381560153478

碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 89 === [(FePt)100-yCry]100-δ-[SiNx]δ(y=0~25 at.%、δ=0~30 vol.%) nanocomposite thin films were prepared by dc & rf magnetron co-sputtering of FePt 、Cr and Si3N4 targets on silicon substrates, then post-annealed in vacuum at various temperatures. The effects of Cr addition and SiNx volume fraction on the magnetic properties and microstructure were investigated. Transmission electron microscopy (TEM) shows that the as-deposited film consists of an amorphous SiNx matrix with spherical fccγphase FePt particles and Cr particles dispersed in it, and the particle size of FePt is aboust 2 nm. Particle size of FePt in this film increased with the annealing temperature but decreased with increasing Cr content. Magnetization measurements indicated that the optimum composition of FePtCr-SiNx occurs at 10 at.% of Cr and 15 vol.% of SiNx after annealing the thin film at 600℃ for 30 min. The coercivity is 3.7 KOe and the average particle size of FePt in this film is 9.5 nm. The nanostructure and the associated magnetic properties of the composite FePtCr-SiNx film is a promising candidate for high-density recording medium.