Sawada Hidetaka, Sasaki Takeo, Hosokawa Fumio, Suenaga Kazutomo
JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan.
JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan.
Micron. 2014 Aug;63:35-9. doi: 10.1016/j.micron.2014.01.007. Epub 2014 Feb 6.
Resolution reduction by a diffraction limit becomes severe with an increase in the wavelength of an electron at a relatively low accelerating voltage. For maintaining atomic resolution at a low accelerating voltage, a larger convergence angle with aberration correction is required. The developed aberration corrector, which compensates for higher-order aberration, can expand the uniform phase angle. Sub-angstrom imaging of a Ge [112] specimen with a narrow energy spread obtained by a cold field emission gun at 60 kV was performed using the aberration corrector. We achieved a resolution of 82 pm for a Ge-Ge dumbbell structure image by high angle annular dark-field imaging.
在相对较低的加速电压下，随着电子波长的增加，衍射极限导致的分辨率降低会变得很严重。为了在低加速电压下保持原子分辨率，需要使用像差校正来增大会聚角。已开发的像差校正器可补偿高阶像差，从而扩大均匀相角。利用该像差校正器，对通过冷场发射枪在60 kV下获得的具有窄能量分布的Ge [112]试样进行了亚埃成像。通过高角度环形暗场成像，我们获得了Ge-Ge哑铃结构图像82 pm的分辨率。
