Current dependency of sub-surface charging of insulators under electron beam irradiation

It is known that even if insulators are covered with conductive layer, an electric charging-up takes place within the insulator below the surface. Such sub-surface charging phenomenon should be clearly understood for a quantitative discussion on electron beam (EB) analyses with backscattered, secondary, Auger electrons and the characteristic X-rays. Several simulations which represent charging process of materials under EB irradiation have been reported.[ 1-41 The most important mechanism of such simulation is the electron beam induced conduction (EBIC) for the quantitative discussion.