To clarify secondary electron (SE) yield and current characteristics of dielectrics due to low-energy electron beam irradiation

we propose an electron scattering

trapping

transport and self-consistent numerical model by combining the Monte Carlo method and the finite difference method.By establishing an improved SE detection platform

we measure the emission SE current of dielectric samples.Results show that

comparing with the impulse electron beam irradiation

the SE yield will decrease evidently under the continuous electron beam irradiation.With irradiation

the SE current and yield reduce to a stable value gradually.Moreover

the SE yield varies slightly with electron beam current

but increases with the increase in the sample thickness.The results provide the theoretical guidance to improve the imaging quality and suppress the charging effect in modern scanning electron microscopy and a new thought for the parameter measurement of dielectrics according to SE characteristics.