کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1680922 | 1518745 | 2012 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Development of electron optical system using annular pupils for scanning transmission electron microscope by focused ion beam Development of electron optical system using annular pupils for scanning transmission electron microscope by focused ion beam](/preview/png/1680922.png)
Annular pupils for electron optics were produced using a focused ion beam (FIB), enabling an increase in the depth of focus and allowing for aberration-free imaging and separation of the amplitude and phase images in a scanning transmission electron microscope (STEM). Simulations demonstrate that an increased focal depth is advantageous for three-dimensional tomography in the STEM. For a 200 kV electron beam, the focal depth is increased to approximately 100 nm by using an annular pupil with inner and outer semi-angles of 29 and 30 mrad, respectively. Annular pupils were designed with various outer diameters of 40–120 μm and the inner diameter was designed at 80% of the outer diameter. A taper angle varying from 1° to 20° was applied to the slits of the annular pupils to suppress the influence of high-energy electron scattering. The fabricated annular pupils were inspected by scanning ion beam microscopy and scanning electron microscopy. These annular pupils were loaded into a STEM and no charge-up effects were observed in the scintillator projection images recorded by a CCD camera.
Journal: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms - Volume 272, 1 February 2012, Pages 145–148