Construction of a very low temperature specimen stage for the 400kV Analytical Atom Resolution Eletron Microscope.

本研究旨在构建适用于400 kV分析型原子分辨电子显微镜（AARM）的超低温样品台。在低温阶段的精心设计下，使400 kV AARM的各项性能得以保持。为此目的，大坂大学和日本电子株式会社的400 kV AARM已被用于测试目前的极低温样品台的能力。样品可以在X和Y轴上以+10倾斜，这对于研究晶体样品是有用的。为了检测特征X射线以分析材料和二次电子以查看SEM图像，目前的低温试样台具有侧入式测角仪样式。然而，这种类型的测角仪对于机械振动非常弱，并且很难获得高分辨率图像。虽然消除振动不是不可能的，但由于资金有限，它是有目的的，并取得了成功 ...更多信息 分辨率为2.5nm，样品的最低温度为30 K。显然，为了直接看到原子的图像，电子显微镜必须具有0.2 - 0.3nm的分辨率，另一种具有高分辨率和极低温度的样品保持器提出了一种适用于超导电子透镜（SCEL）中样品台的液氦温度。虽然该样品台可以在液氦温度下显示样品的原子结构，但无法检测到特征X射线，也无法进行温度变化。然而，可以使用在显微镜底部制造的电子能量损失谱仪进行元素分析。原子及其团簇的运动也可以用电视摄像机观察，并用录像机记录下来.利用从侧面进入AARM的极低温样品台和SCEL中的低温台，对超导材料<Nb_3>Sn在从室温到30 K的不同温度下的图象进行了观察，在5 K条件下，获得了Th-焦汞化合物的原子分辨像，并研究了电子辐照对Th-焦汞化合物的影响。实验结果表明，低温样品台的性能可以得到改善。经过改进后，低温样品台的温度降低到20 K，但样品处的机械振动却高达20 nm。振动的起因目前正在研究中，但报告了迄今为止获得的结果。目前的调查正在向冈山理科大学和文部科学省申请在冈山理科大学安装400 kV AARM，并计划与低温研究小组一起在原子尺度上进行广泛的低温研究。少

The present research aimed to construct the very low temperature specimen stage adaptable to 400kV Analytical Atom Resolution Electron Microscope (AARM). The low temperature stage has been made by paying the careful attention which enable every performance of the 400kV AARM to be preserved. For this aim, Both the 400kV AARM in Osaka University and in JEOL Ltd. has been used for testing the capabilities of the present very low temperature specimen stage.Specimens can be tilted in both X and Y axes with +10 , which is useful to study the crystalline specimens. In order to detect the characteristic X-ray to analyze the materials and secondary electrons to see the SEM images, the present low temperature specimen stage has the side entry goniometer style. However,this style of the goniometer is very weak for mechanical vibration and rather difficult to obtain high resolution images. Though elimination of the vibration is not impossible, since the fund is limited, it was aimed and succeeded … More that the resolution is 2.5 nm and the lowest temperature of a specimen is 30 K.Since it is clear that the electron microscope must have the resolution of 0.2 -0.3 nm in order to see the images of atoms directly, another specimen holder with high resolution and very low temperature ( the temperature of the liquid helium ) adaptable to the specimen stage in the superconducting electron lens (SCEL) has been made for reference. Though this specimen stage can reveal the atomic structure of the specimen in liquid helium temperature, the characteristic X-ray cannot be detected and also no temperature variation can be carried out. However element analysis can be carried out using the electron energy loss spectrometer fabricated at the bottom of the microscope. Movement of atoms and their clusters can also be observed by TV-camera and recorded in video tape recorder (VTR).Using the side entry very low temperature specimen stage to the AARM together with the low temperature stage in the SCEL, some observations of images of a superconducting material <Nb_3> Sn at various temperatures from room temperature to 30 K, atom resolution images of Th-pyromeritate at 5 K and the variation of Th-pyromeritate by electron irradiation at 5 K have been carried out. Some variation of the images were recorded in VTR.After the present research, it was known that the performance of the low temperature specimen stage can be improved. After some improvements, the temperature of the present low temperature specimen stage was lowered to be 20 K but the mechanical vibration becomes as large as 20 nm in the specimen position. The origin of the vibration is now under studying, but the results obtained so far are reported.The present investigations are now applying to the Okayama University of Science and the Ministry of Education , science and Culture to install 400 kV AARM in Okayama University of Science and planning to carry out the extensive low temperature research in atomic scale together with low temperature research group. Less