The fabrication and application of Zernike electrostatic phase plate

Abstract

The Zernike electrostatic phase plate (ZEPP) consisting of three ring electrodes and two insulating rings has been fabricated using Micro Electro-Mechanical System processes. The electrostatic field produced in the phase plate was measured by electrostatic force microscopy. The electrostatic field and focal length of the phase plate is calculated using electron optics principles. The comparison of the experimental electrostatic field and the theoretical calculated is discussed. Finally, we report the application of ZEPP to enhance contrast of the SiON(x)/SiO(2) interface in an NMOS semiconductor device. The quantitative analysis of the contrast enhancement versus the applied bias is discussed in detail.

Single particle analysis based on Zernike phase contrast transmission electron microscopy

“…In future, phase plates based on electromagnetic fields (Tonomura, 1988;Huang et al, 2006;Majorovits et al, 2007;Cambie et al, 2007) could improve the situation, making ZPC-TEM capable of achieving reconstructions with better resolution than those possible with CTEM. Current electrostatic phase plates suffer from a relatively large obstruction at the diffraction plane by electrodes or support rods which block the lower frequencies, and adaptation of both the phase plate and the TEM will most likely be necessary.…”

“…Most of them showed promising ''proof of concept'' results, but were eventually abandoned because of various practical problems. Recently, interest in such devices has been reborn and is growing rapidly (Nagayama, 1999;Nagayama, 2001, 2006;Nagayama and Danev, 2003;Lentzen, 2004;Hosokawa et al, 2005;Huang et al, 2006;Majorovits et al, 2007;Cambie et al, 2007;Malac et al, 2007). These devices work by modulating the phase of the electron wave at a diffraction plane.…”

Retrofit implementation of Zernike phase plate imaging for cryo-TEM

“…Electrostatic phase plates of the einzel-lens type (Majorovits et al, 2007; Huang et al, 2006), or the drift-tube type (Cambie et al, 2007), have a central element that shifts the phase of the unscattered electrons. The structure of the central element, and its supporting wire(s), blocks information transfer, especially at low spatial frequencies.…”

Fabrication and Characterization of a High-Performance Multi-Annular Backscattered Electron Detector for Desktop SEM

“…The BSE image contrast for three different BSE detectors (MA-, MA p-n and MA-Al) were quantified using a sample of mixed gold and polystyrene particles. The image contrast C can be quantified as [22], $\mathrm{normalC}=\frac{\left|{\mathrm{I}}_{\mathrm{Signal}}-{\mathrm{I}}_{\mathrm{Background}}\right|}{\sqrt{{\mathsf{\sigma }}_{\mathrm{Signal}}^2+{\mathsf{\sigma }}_{\mathrm{Background}}^2}}$ where I Signal and I Background are the averaged intensity from the circled gold particle and the silicon substrate, respectively, while the σ Signal and the σ Background are the standard deviation of these two parts, respectively. As shown in Figure 10, the contrast of images has been obtained at the electron energy of 10 keV.…”