Research on ferrite thin film with isolated small and pillar like structure for high density HDD medium

高密度硬盘介质用孤立小柱状结构铁氧体薄膜的研究

• 批准号: 16360149
• 负责人: MORISAKO Akimitsu
• 金额: $ 9.66万
• 依托单位: SHINSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16360149/
• 关键词: high density recording medium; nano dot; hexagonal ferrite; small particle; patterned media; perpendicular magnetic recording; sputtering; self seembled; ナノスポット結晶化; 微粒子化薄膜; バリウムフェライト; 自己組織化; 磁気記録媒体; Al-Si; ナノドット; 記録媒体; スパッタリング; ナノサイズ; 高密

High density recording in hard disk drive(HDD) system is still key issue even though a perpendicular magnetic recording system is now on the market. The recording medium for a next generation must be discrete type or patterned media type to attain an ultra high recording density greater than one tera bits per square inch. The magnetic grains must be small to reduce the media noise. Furthermore, the grains must be isolated. In this study, nano-spot crystallization for barium ferrite thin film has been tried to prepare the nano-spot array film of barium ferrite. The Ba-Fe-O films deposited at room temperature is amorphous and has no magnetization. The Ba-Fe-O films deposited on silicon wafer can be crystallized at around 700 C and show magnetic properties. In this study to lower the crystallization temperature for barium ferrite thin film, several kind of under layer materials were examined. As a results Pd-Pt mixed alloy underlayer is suitable for lowering the substrate temperature and … More very small particle. The Al film was also examined as an under layer for amorphous barium ferrite thin film. The amorphous Ba-Fe-O layer on Al under layer can be crystallized at around 650 C. This is 50 C lower than that for silicon under layer. It is know that Al-Si alloy is a phase separate material and nano-sized Al spots are synthesized in silicon matrix. It was tried to prepare barium ferrite with nano-spot like structure using Al-Si under layer. A self assembled nano dots array of Al can be created by phase separation at the substrate temperature of 250 C. Then ampourphous Ba-Fe-O films were deposited at room temperature and post-deposition annealed at 650 C. The measured magnetization is corresponding to Al content. This means that barium ferrite layer on Al spot can only be crystallized and other parts, which are on silicon matrix, are still amorphous and no magnetization. Due to the resolution limits, it is not yet confirmed that nano spot barium ferrite film was prepared. The delta M plots show that the magnetic grains are separated and exchange coupling is weakened. In conclusion, new technique to prepare a patterned medium using self assembled Al-Si under layer. Less

尽管垂直磁记录系统现已上市，但硬盘驱动器（HDD）系统中的高密度记录仍然是关键问题。下一代记录介质必须是离散类型或图案化介质类型，以获得大于每平方英寸1太比特的超高记录密度。磁性颗粒必须很小，以减少介质噪音。此外，必须分离谷物。本研究尝试采用钡铁氧体薄膜纳米点晶化技术制备了钡铁氧体纳米点阵列薄膜。室温下沉积的Ba-Fe-O薄膜是非晶态的，不具有磁化作用。沉积在硅片上的Ba-Fe-O薄膜可以在700℃左右结晶并表现出磁性。在本研究中，为了降低钡铁氧体薄膜的结晶温度，对几种底层材料进行了研究。因此，Pd-Pt混合合金底层适合降低基体温度和非常小的颗粒。还对作为非晶钡铁氧体薄膜的底层的Al膜进行了检查。 Al底层上的非晶Ba-Fe-O层可以在650℃左右结晶。这比硅底层低50℃。众所周知，铝硅合金是一种相分离材料，在硅基体中合成了纳米级的铝点。尝试利用Al-Si底层制备具有纳米点状结构的钡铁氧体。在250℃的衬底温度下通过相分离可以产生自组装的Al纳米点阵列。然后在室温下沉积无定形Ba-Fe-O薄膜并在650℃下进行沉积后退火。测量的磁化强度对应于Al含量。这意味着Al点上的钡铁氧体层只能结晶，而硅基体上的其他部分仍然是非晶态，没有磁化。由于分辨率的限制，目前尚未证实纳米点状钡铁氧体薄膜的制备。 δ M 图显示磁性颗粒分离并且交换耦合减弱。总之，采用自组装铝硅底层制备图案化介质的新技术。较少的

项目成果

バリウムフェライト薄膜を用いた高密度パターン媒体の基礎研究

使用钡铁氧体薄膜的高密度图案介质的基础研究

• 发表时间: 2006
• 期刊: 電気学会マグネティックス研究会 MAG-06-102
• 作者: 森迫昭光;山本修己;劉 小晰
• 通讯作者: 劉 小晰

Manipulation of crystal orientation and microstrucutre of barium ferrite thin film

钡铁氧体薄膜晶体取向和微观结构的调控

• 发表时间: 2005
• 期刊: Journal of Magnetism and Magnetic Materials 290-291
• 作者: N.N.Shams;X.Liu;M.Matsumoto;A.Morisako
• 通讯作者: A.Morisako

C-axis oriented Ba-ferrite thin film with small grain for perpendicular magnetic recording

用于垂直磁记录的小晶粒C轴取向Ba铁氧体薄膜

• 发表时间: 2004
• 期刊: Journal of Magnetism and Magnetic Materials 272-276
• 作者: A.Morisako;N.N.Shams;Y.Miura;M.Matsumoto;S.H.Gee;M.H.Park;Y.K.Hong
• 通讯作者: Y.K.Hong

Magnetic properties of hexagonal ferrite dot array

六方铁氧体点阵的磁性能

• 发表时间: 2006
• 期刊: Journal of Magnetism and Magnetic Materials 303
• 作者: X.Liu;A.Morisako
• 通讯作者: A.Morisako

Crystallographic and magnetic properties of barium ferrite thin films on various underlaver

各种紫菜上钡铁氧体薄膜的晶体学和磁性

• 发表时间: 2004
• 期刊: Proc.of Ninth International Conference on ferrites (American Ceramic Society)
• 作者: N.N.Shams;H.B.Mohammad;X.Liu;M.Matsumoto;A.Morisako
• 通讯作者: A.Morisako