Quantitative Evaluation of Charging on Amorphous SiO2 Particles by Electron Holography
2001 年 42 巻 9 号 p. 1882-1885
詳細
2001 年 42 巻 9 号 p. 1882-1885
The amount of the electric charge in spherical SiO2 particles with 1 \\micron diameter has been evaluated quantitatively by using electron holography. The charging effect was found to depend on not only the incident electron intensity but also the insertion of an objective aperture. The amount of the electric charge in a SiO2 particle is estimated to be 1.5×10−16 C under the current density of incident electron beam at 0.5 A/m2 without an objective aperture. This electric charge is equal to the net loss of about 940 electrons from the amorphous SiO2 particle. In the case of inserting an objective aperture, the amount of the electric charge on SiO2 particles decreases by 30–40%. The results are compared with the cases of Au coated particles and the small particles of 250 \\micron in diameter.
