Effects of underlayer materials and substrate temperatures on the structural and magnetic properties of Nd2Fe14B films

• 来源期刊: 中国物理（英文版）
• 关键词: Nd2Fe14B film underlayer substrate temperature texture
• 年，卷（期）: 2004,（11）
• 页码范围: 1969-1974
• 页数: 6页
• 语种: 英文

摘要

Thin films of Nd2Fe14B were fabricated on heated glass substrates by dc magnetron sputtering. Different material underlayers (Ta, Mo, or W) were used to examine the underlayer influence on the structural and magnetic properties of the NdFeB films. Deposited on a Ta buffer layer at 420℃, the 300 nm thick NdFeB films were shown to be isotropic.But when the substrate temperature Ts was elevated to 520℃, the Nd2Fe14B crystallites of (00l) plane were epitaxially grown on Ta (110) underlayer. In contrast, Mo (110) buffer layer could not induce any preferential orientation in NdFeB film irrespective of the substrate temperature or film thickness. The W buffer layer was found to be most effective for the nucleation of Nd2Fe14B crystallites with c-axis alignment perpendicular to the film plane when Ts ＜ 490℃. But at Ts=490℃ the magnetic layer became isotropic. The maximum coercivity obtained was about 995 kA/m for the 100nm film deposited on W underlayer at 490℃. These variations were tentatively explained in terms of the lattice misfit between the underlayer and the magnetic layer, combined with the considerations of underlayer morphologies.