Development of electron beam nonostructure analysis system and its application

电子束非结构分析系统的研制及其应用

基本信息

批准号：
09450236
负责人：
HIROTSU Yoshihiko
金额：
$ 9.73万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

In recent years, nano-structure analysis has been becoming important to develop new types of functional nanostructured materials. We recently performed nano-diffraction studies for local structure analysis of several new materials with nano structures such as magnetic nano-granular films and amorphous alloys. For the purpose of detailed local structure analysis, it is necessary to make nano-diffraction and HREM study at the same local area from different orientations. When we observe a local structural area in a specimen under a high magnification, the observation position of interests easily goes out of the observation screen by tilting the specimen. This makes our high-resolution observation and nano-diffraction of local areas difficult under various orientation directions. This is primarily because the observation position is not exactly on the cross-point of tilting x and y-axes. We have developed an auto-correction system for the specimen positional-shift on large angle specimen-tilting taking advantage of the projector-lens-deflection coils. Software necessary to tilt the specimen stage toward an arbitrary orientation was also developed. In this system the image-escape by a step-wise tilt is searched by the TV-monitor, and the escape-vector is calculated by computer using the convolution algorism. The image-escape with the escape-vector is compensated using the projector-lens-deflection. The merit of this system is that we need not observe the diffraction patterns during the specimen tilting towards our intended specimen orientation, though the tilting procedure still takes a considerable time (5-10 mm). In achieving an auto-tilt for the HREM purpose, we need to develop a precision-specimen drive with a quick movement to change more precisely and quickly the orientation in future. The present investigation will be the primary step for the nano-area crystal structure analysis technique with HREM and nano-diffraction.

近年来，纳米结构分析对于开发新型功能纳米结构材料变得越来越重要。我们最近进行了纳米衍射研究，对磁性纳米颗粒薄膜和非晶合金等几种具有纳米结构的新材料进行了局部结构分析。为了进行详细的局部结构分析，需要在同一局部区域从不同方向进行纳米衍射和HREM研究。当我们在高倍率下观察标本的局部结构区域时，由于倾斜标本，感兴趣的观察位置很容易超出观察屏幕。这使得我们在各种取向方向下对局部区域进行高分辨率观察和纳米衍射变得困难。这主要是因为观察位置并不正好位于倾斜的 x 轴和 y 轴的交叉点上。我们利用投影仪镜头偏转线圈开发了一种自动校正系统，用于大角度样品倾斜时的样品位置偏移。还开发了将样品台向任意方向倾斜所需的软件。在该系统中，电视监视器通过逐步倾斜搜索图像逃逸，并且计算机使用卷积算法计算逃逸矢量。使用投影仪镜头偏转来补偿具有逃逸矢量的图像逃逸。该系统的优点是，尽管倾斜过程仍然需要相当长的时间（5-10毫米），但我们不需要在样品向我们预期的样品方向倾斜期间观察衍射图案。为了实现 HREM 目的的自动倾斜，我们需要开发一种可快速移动的精密样本驱动器，以便将来更精确、更快速地改变方向。目前的研究将是利用 HREM 和纳米衍射的纳米区域晶体结构分析技术的第一步。