权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

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.

本研究的主题是制备磁性颗粒薄膜的精细结构。磁性颗粒膜是一种新型磁性物质。具体来说，它的目标是在非晶薄膜中产生小于几十纳米的精细磁性颗粒区域。到目前为止，还没有一种方法可以研究这种小区域的磁态。因此，我们首先要实现对小于10nm的细颗粒磁性的观察。为了形成颗粒区域的图案，要求原始基体为非晶或直径小于1nm的超细晶粒的多晶。本项目取得了以下成果：i)我们找到了用直流磁控溅射法制备Fe_8Mo_2非晶膜的条件。(2)利用带场发射电子枪和磁屏蔽电子透镜的透射电子显微镜，成功地观察了Fe颗粒嵌套在MgO单晶和Fe_8Mo_2非晶膜中沉淀在Fe_8Mo_2非晶膜中的Fe颗粒在10 nm以内具有单一磁畴的细颗粒的磁态。(3)利用透射电镜加热台辅助200kev的电子辐照，实现了Fe_8Mo_2非晶膜中部分细小颗粒的析出。在非晶膜中发现了一个宽度小于100 nm的“N”字颗粒区。通过洛伦兹显微镜发现该区域部分颗粒具有自磁化特性，小面积x射线分析证实该区域颗粒中Fe在基体上的原子浓度大于80%。