Article dans une revue avec comité de lecture


Measurement of internal electric field in coated grounded quartz irradiated by an electron beam
Nucl. Instr. and Meth. in Phys. Res. B 197 114 (2005).

par   N. Ghorbel , O. Hachicha , Slim FAKHFAKH , Omar JBARA , Z. Fakhfakh , A. Kallel

Résumé :

Abstract

Phys. mechanisms involved in insulators submitted to electron irradn. inside a scanning electron microscope (SEM) were investigated by combining some simple considerations of electron trapping mechanisms with basic equation of electrostatics. To understand such mechanisms, only widely irradiated samples having a uniform trapping sites distribution are considered. This hypothesis leads to develop simple models for the trapped charge distributions and subsequently for the distribution of the elec. field build-up in ground coated specimens as investigated in electron probe microanal. (EPMA). This enables us to study the distortion of the ?(?z) function (the depth distribution of characteristic x-ray prodn.) as well as the modification of the specimen’s local compn. An exptl. method, using a series of quartz samples, is described for evaluating the magnitude of the elec. field build-up within specimens ; thus allowing to establish clearly the elec. field influence on the measured ?(?z) function.