Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8163518 | Physica B: Condensed Matter | 2013 | 5 Pages |
Abstract
Insulators are currently used in high technological devices. They are chosen because of their electrical properties of insulation and their thermal properties. It is well known that the presence of space charge in an insulator is correlated with an electric breakdown. Charging phenomena of insulator were studied thanks to a scanning electron microscope (SEM) which allows the injection of few electrons doses in a large domain of energies. SEM permits also the measurements of the secondary electron emission and the induced current created in the sample holder by the charges generated in the sample. The results showed that the secondary electron emission yield (SEE) Ï is a very sensitive parameter to characterize the charging state of an insulator. In this work we investigate the charging effect of insulator surfaces like pur spinel (MgAl2O4) during 1.1, 5 and 15Â keV. The results showed that the fundamental parameter controlling the charging kinetic is the current density J0. At low energies 1.1 and 5Â keV, two different kinds of self-regulated regime (Ï=1) were observed as a function of current density. At 15Â keV energy, the electron emission appears to be stimulated by the current density, due to the Poole-Frenkel effect.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
A. Boughariou, A. Kallel, G. Blaise,