Fabrication of Highly Oriented Fe Films by Thermal CVD with Imposition of Magnetic Field

通过施加磁场的热 CVD 制备高取向铁薄膜

• 批准号: 12650687
• 负责人: YOSHIKAWA Noboru
• 金额: $ 0.45万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650687/
• 关键词: CVD; iron film; strong magnetic field; magnetic anisotropy; magnetization force; grain structure; 磁化力; 結晶粒構造; 鉄膜; 鉄; 薄膜; 組織; 成膜速度; 磁気特性

In this research, CVD reaction system of reducing iron chloride (FeCl_3) with hydrogen (H_2) was utilized. During the CVD process, steady magnetic field was imposed.Fist of all, fundamental deposition conditions were determined by imposition of 0.5T with non-superconducting magnet, then the microstructural characterization methods were established, such as XRD, TEM and FE-SEM.In the second stage, CVD apparatus was placed in the superconducting magnet installed in High Field Laboratory for Superconducting Materials, Institute for Materials Research, Tohoku University. Fabrication of Fe films and characterization of their microstructure and crystal orientation were conducted. The obtained results are summarized as follows :1. It was found that the vaporized amount of FeCl_3 increased as an increase of magnetic field intensity. Especially, this tendency was obvious above 5T.2. Island-shaped crystals are formed first, then the films are formed through their coalescence occurs. This type of the growth mode might be due to difficulty in nucleation of Fe crystals on an amorphous SiO_2 substrate.3. Fraction of cube-shaped island-shaped crystals increased, as an increase of magnetic field intensity. Simultaneously, degree of (100) orientation increased, which is consistent with the easy- magnetization axis of iron crystals. The preferred nucleation might be induced by the imposition of the magnetic field.4. Degree of (100) orientation decreased when island-shaped crystals changed to films. The films have Zone III grain structure because of the relatively high substrate temperature (〜0.5Tm of Fe). Occurrence of considerable grain boundary migration in the films might be related to the disappearance of (100) texture.

本研究采用H_2还原FeCl_3的CVD反应体系。在CVD过程中，施加恒定磁场，首先采用非超导磁体施加0.5T磁场，确定了基本的沉积条件，然后建立了XRD、TEM和FE-SEM等微观结构表征方法。第二阶段，将CVD装置置于材料研究所超导材料高场实验室的超导磁体中，东北大学。制备了Fe薄膜，并对其微观结构和晶体取向进行了表征.主要研究结果如下：1.实验结果表明，随着磁场强度的增加，FeCl_3的蒸发量增加。特别是在5T.2以上，这种趋势更为明显。首先形成岛状晶体，然后通过它们的聚结形成膜。这种生长方式可能是由于Fe晶体在非晶SiO_2衬底上难以成核.随着磁场强度的增加，立方岛状晶体的比例增加。同时，（100）取向度增加，这与铁晶体的易磁化轴相一致.优选的成核可以通过施加磁场来诱导。岛状晶体转变为薄膜后，（100）取向度降低。由于衬底温度相对较高（Fe的温度为~ 0.5Tm），薄膜具有III区晶粒结构。薄膜中晶界迁移现象的发生可能与（100）织构的消失有关。

项目成果

N.Yoshikawa, T.Endo, S.Awaji, S.Taniguchi: ""Texture and Grain Structure of Iron Films Obtained by CVD with Imposition of Magnetic Field""Proceedings of 13th International Conference on Texture of Materials (ICOTOM 13). in press.

N.Yoshikawa、T.Endo、S.Awaji、S.Taniguchi：“通过施加磁场的 CVD 获得的铁膜的织构和晶粒结构”第 13 届国际材料织构会议 (ICOTOM 13) 论文集。

T.Endo, N.Yoshikawa, S.Awaji, S.Taniguchi: "Fabrication of Iron Film by Thermal CVD with Imposition of Magnetic Field"Transaction of Materials Society of Japan. (印刷中).

T.Endo、N.Yoshikawa、S.Awaji、S.Taniguchi：“通过施加磁场的热 CVD 制造铁膜”，日本材料学会会刊（正在出版）。

N.Yoshikawa, T.Endo, S.Awaji, E.Aoyagi, S.Tanigushi: "Texture and Grain Structure of Iron Film Obtained by CVD with Imposition of Magnetic Field"Proceedings of 13th International Conference on Textures of Materials(ICOTOM13). (印刷中).

N.Yoshikawa、T.Endo、S.Awaji、E.Aoyagi、S.Tanigushi：“通过施加磁场的 CVD 获得的铁膜的织构和晶粒结构”第 13 届国际材料织构会议 (ICOTOM13) 论文集。 （在新闻）。

T.Endo, N.Yoshikawa, S.Awaji, S.Taniguchi: ""Fabrication of Iron Films by Thermal CVD with Imposition of magnetic Field""Transactions of Materials Research Society of Japan. in press.

T.Endo、N.Yoshikawa、S.Awaji、S.Taniguchi：“通过施加磁场的热 CVD 制备铁膜””日本材料研究学会汇刊。

T.Endo, N.Yoshikawa, S.Awaji, S.Taniguchi: "Fabrication of Iron Films by Thermal CVD with Imposition of Magnetic Field"Transactions of Materials Society of Japan. (印刷中).

T.Endo、N.Yoshikawa、S.Awaji、S.Taniguchi：“通过施加磁场的热 CVD 制造铁膜”日本材料协会汇刊（正在出版）。