Fabrication and Magnetic Study of FePt Thin Films

• Main Authors: Yuan Fu Te, 袁輔德
• Other Authors: Chen Shih Kun
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/32051443270368928890

碩士 === 逢甲大學 === 材料科學學系 === 89 === Abstract We deposited FePt thin films by high vacuum RF sputtering system. The film thickness is 200 nm. Heat treatment was done by heating the substrate during depositing process and keep the same temperature for 10 minutes after sputtering. The composition range we researched was from Fe15Pt85 to Fe75Pt25. We analysis the changes of magnetic properties between several compositions in the heat treatment range 400℃~700℃. We found that, mostly the magnetic properties of the composition of Fe45Pt55 is better than Fe50Pt50. The best Hc is 9 kOe, and (BH)max is 28 MGOe. The Si(100) substrates induced an effect of preferred orientation changed from (111) plane to (110) plane. The plethora Pt atoms show a tendency to form a slightly preferred orientation at (202) plane. We also found the affection of ordering paramater to the overall magnetic properties of FePt thin films decreased step by step, when the degrees of order exceeded 0.6. In the research of adding Nb base on the Fe50Pt50 composition. We found the third element enhanced the squareness (S, S*) and remanence (Mr) of the FePt thin films, but decreased the coercivity (Hc) and grain size at the same time. Magnetic properties has achieve the optimum conditions and (BH)max equals to 30 MGOe, when Nb was added 0.83 at﹪and heat treated at 500℃. It also corresponded to a maxmum exchange coupling force. On the other hand, the lattice constant change was following the concentrations of Nb atoms, too. It means that the effect of FePt lattice distortion of Nb atoms was very slightly.