CHARGING PHENOMENA ON INSULATING MATERIALS - MECHANISMS AND APPLICATIONS

We are interested in the physical origin of the electric charge that is produced in insulators by electron bombardment, by an electric field, or by mechanical stress. The charge is due to the trapping of carriers on the defects formed in the course of the dissipation of energy by the lattice. The characteristics of the charge (potential, electric field) result from the laws of electrostatics. The stability of the charge under an electron beam is interpreted on the basis of the laws governing the behavior of the discharges in gases and in solids. The stability of the charge after shutting off the beam depends on the position of the traps with respect to the surface and the experimental conditions (gas pressure, temperature, time). The charge decay kinetics are then controlled by adsorption‐diffusion. These studies allow us to explain some of the electromigration phenomena that had not been interpreted and to determine the optimal experimental conditions for the observation of local variations in the dielectric constant; they also allow the use of the charge phenomenon as an indicator of the mechanical and dielectric properties of insulators. Copyright © 1990 Foundation for Advances in Medicine and Science, Inc.