Fundamental Study on magnetic-granular films with fine structures

精细结构磁性颗粒薄膜的基础研究

基本信息

批准号：
08455142
负责人：
TANJI Takayoshi
金额：
$ 4.74万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

The theme of this research is to make fine structures of magnetic granular thin films. Magnetic granular films have been remarked as one of new magnetic substances. Specifically, it has been aimed to produce fine magnetic-granular areas less than a few tens nanometers in an amorphous thin film. No method to investigate the magnetic state in such small region bad been confirmed, so far. Therefore, first of all, we had to realized the observation of the magnetism of fine particles less than 10 nm. In order to make a pattern of granular area, the original matrix is required to be amorphous or a poly-crystal of ultra fine grains less than 1 nm in diameter.Following results have been obtained in this project ;i) We have found the condition to make an amorphous film of Fe_8Mo_2 using a DC magnetron sputtering method.ii) By Lorentz electron microscopy using a transmission electron microscope instrument equipped with a field emission electron gun and a magnetically shielded electron lens, we observed successfully the magnetic states of fine particles less than 10 nm which have single magnetic domains in the case of Fe particles embedded in a MgO single crystal and Fe particles precipitated in a Fe_8Mo_2 amorphous film.iii) We have realized to precipitate partially fine particles in the Fe_8Mo_2 amorphous film by 200 keV electron irradiation with an assist of a heating stage for transmission electron microscopy. A character "N" of granular area wi th the width less than 100 nm was drown in the amorphous film. Some particles in such area was found to have self magnetization by Lorentz microscopy, and small area x-ray analysis confirmed that the atomic concentration of Fe in such particles is la rger than 80% on the matrix.

这项研究的主题是制造磁性颗粒薄膜的精细结构。磁性颗粒膜被称为新的磁性物质之一。具体而言，它的目的是在无定形薄膜中产生小于几十纳米的细磁颗粒区域。到目前为止，还没有确认在如此小的区域中研究磁态的方法。因此，首先，我们必须意识到观察到小于10 nm的细颗粒的磁性。为了建立颗粒状区域的模式，原始基质必须是无定形的或直径小于1 nm的超细晶粒的多晶体。使用DC Magnetron溅射方法制作Fe_8Mo_2的无定形膜，使用洛伦兹电子显微镜使用透射电子显微镜仪器，配备了带有磁场发射电子枪和磁性屏蔽的电子镜头，我们成功地观察到了较小的磁性颗粒的磁性状态在嵌入Fe_8mo_2无定形膜中沉淀在MGO单晶中的Fe颗粒的情况下，具有单个磁性域的10 nm，我们已经意识到在Fe_8mo_2的Fe_8mo_2中沉淀出部分细颗粒。辅助加热阶段用于透射电子显微镜。颗粒区域的角色“ N”小于100 nm的宽度被淹没在无定形膜中。发现该区域中的一些颗粒通过洛伦兹显微镜具有自我磁化，而小面积X射线分析证实，这种颗粒中Fe的原子浓度比基质的80％rger。