Development of a specimen-cooling holder for the electron microscpe utilizing a refrigeratorrial using high-voltage electron microscopy

电子显微镜的原位观察提供了关于材料中缺陷的结构变化和行为的独特信息。到目前为止，重点一直放在高温下发生的现象上。然而，从高温超导体可以看出，在很低的温度下进行原位观察已经引起了人们的广泛关注。然而，这里的问题是，使用液氦的现场实验很难进行，因为液氦的处理需要相当的技能。因此，只有少数研究小组能够在极低的温度（如10K）下进行原位冷却实验。然而，最近出现了一种高性能的制冷机，并已应用于超导磁体等领域。本项目的目的是利用制冷机冷却电子显微镜中的样品。预期这种冷却保持器的发展使得在很低温度下的原位冷却实验更容易作为常规工作来进行。在本项目中，已经设计了这样的冷却保持器，并且已经构造了初步的保持器。不幸的是，这个保持器不是一个完整的。但是希望这种冷却保持器在不久的将来能够商业化制造。

In-situ observation in the electron microscope gives unique information on structural changes and behavior of defects in materials. So far, emphasis has be placed on phenomena taking place at high temparature. However, as can be seen from hign-temperature superconductors, in-situ observation at very low temperature has gathered much attention. However, problem here is that an in-situ experiment using liquid helium is very difficult to carry out because handling of liquid helium needs considerable skills. For this reason, only a limited number of groups have managed to carry out in-situ cooling experiments at very low temperature such as 10K.However, recently a high-performance refrigerator is available and has been applied to superconducting magnets and so on. The purpose of the present project is to utilize the refrigerator to cool a specimen in the elecoscope. It is expected that development of such a cooling holder makes in-situ cooling experiments at very low temprature to be carried out more easily as a routine workIn the present project such a cooling holder has been designed and a preliminary holder has been constructed. Unfortunately this holder is not a completed one. But it is hoped that such a cooling holder will be comercially manufactured in near future.