Development of illumination system of gun-damage free electron microscope

枪伤自由电子显微镜照明系统的研制

• 批准号: 02559011
• 负责人: SHIMOMURA Yoshiharu
• 金额: $ 3.46万
• 依托单位: Hiroshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02559011/
• 关键词: Ion Irradiation Damage; Gun-Damage; Electron Microscope; Illumination System; Displacement Cascade Damage; Irradiation Damage; Neutron Irradiation Damage

In a present day's electron-microscope (EM)some sort of negative ions is formed near filament. These ions are accelerated, pass through condenser lenses and illuminate uniformly on specimen. The energy of ions is 200 key so that these ions can form displacement damage cascades in specimens. These damages are referred to as "gun damages". The present investigators found that this kind of gun damage formation is significant in presently available EM and make difficult to study the damage formation in ion- and neutron-irradiated metals. In the present project, new system was developed to eliminate these gun damage formation in specimens. Two systems were built : One is the shift perpendicularly the gun part to the optical axis of electrons in EM. Another-is the bend of electron path in a specimen chamber (above specimbns) to form by-pass. In the straight path, the stopping plate is inserted to block gun-forming ions. We have installed these equipments to our JEM-2000ES microscope and tested their performances at 200 kV accelerating voltage. Both of apparatus works very well. Gun damage formation was eliminated perfectly with both of apparatus and moreover contamination formed during electron-illumination was remarkably decreased. This fact suggests that contamination which forms during an elgidtron-microscope observation is due to ions which come from gun chambers. The illumination system of gun-damage free of an electron-microscope will be equipped to a future electron-microscope as standard configuration.

在当今的电子显微镜（EM）中，在灯丝附近会形成某种负离子。这些离子被加速，穿过聚光镜，均匀地照射在样品上。离子的能量为200键，使这些离子可以在试样中形成位移损伤级联。这些损害被称为“枪支损害”。目前的研究人员发现，这种枪损伤的形成是显着的，在目前可用的EM和难以研究的离子和中子辐照金属的损伤形成。在本项目中，开发了新的系统，以消除这些枪损伤形成的标本。建立了两套系统：一套是电子枪部分垂直于电子光轴的位移系统;另一种是电子路径在样品室中（在样品室上方）的弯曲，形成旁路。在直线路径中，挡板被插入以阻挡形成枪的离子。我们已经将这些设备安装到我们的JEM-2000 ES显微镜，并在200 kV加速电压下测试了它们的性能。这两种仪器都工作得很好。这两种装置都能很好地消除电子枪损伤的形成，并显著减少电子辐照过程中产生的污染。这一事实表明，在elgidtron显微镜观察过程中形成的污染是由于来自枪室的离子造成的。电子显微镜的无枪伤照明系统将作为标准配置配备到未来的电子显微镜。

项目成果

SHIMOMURA, Yoshiharu: "Cryotransfer TEM observation of displacement cascade damages of Au, Ag and Cu irradiated with D-T neutrons at low temperature" J. Nucl. Mater.

SHIMOMURA, Yoshiharu：“低温转移 TEM 观察 D-T 中子在低温下辐照的金、银和铜的位移级联损伤”J. Nucl。

下村 義治: "Cryotransfer TEM observation of displacement cascade damages of Au,Ag and Cu irradiated with DーT neutrons at low temperature" J.Nucl.Mater.

Yoshiharu Shimomura：“低温转移 TEM 观察受 D-T 中子辐照的金、银和铜的位移级联损伤”J.Nucl.Mater。

FUKUSHIMA, Hiroshi: "Gun-Damage-Free' TEM Equipped with a Slide-Gun-Chamber" J. Electron Microsc.(1992)

FUKUSHIMA, Hiroshi：“配备滑枪室的无枪损伤”TEM”J. Electron Microsc.(1992)

下村 義治: "Group formation of interstitial clusters in DーT neutronーirradiated Au,Ag and Cu examined by improved cryotransfer TEM" Proc.of ICFRMー5 (international conference on fusion reactor materialsー5,Maimami,Nov.1991. (1991)

Yoshiharu Shimomura：“通过改进的低温转移 TEM 检查 D-T 中子辐照的金、银和铜中的间隙团簇形成”Proc. ICFRM-5（聚变反应堆材料国际会议 - 5，Maimami，1991 年 11 月。1991 年）

向田 一郎: "Small dot TEM images appeared during electronーillumination of nickel" J.Electron Microscopy.

Ichiro Mukoda：“在镍的电子照射过程中出现小点 TEM 图像”J.Electron Microscopy。