INSULATOR CHARGING UNDER IRRADIATION WITH A STATIONARY ELECTRON-PROBE

The charging of an insulator surface when irradiated with a stationary low-energy electron probe is simulated by Monte Carlo techniques. Results show that the irradiated core initially charges positively, causing a potential barrier to form, thereby attracting lower energy secondary electrons back towards the surface. However, as negative charge accumulates around the core periphery, more secondary electrons are returned to the core, which leads to a negative drift in the core potential. The core is expected to reach an equilibrium negative potential.