Analysis of electron range versus energy relationship of insulators in low‐voltage scanning electron microscopy

摘要

AbstractA theoretical analysis is made concerning the question of whether or not an insulator's surface is observable without the unstable disturbance due to negative charge‐up in the secondary electron mode of a low‐voltage scanning electron microscope. Introducing a simple modification into the elementary theory of secondary electron emission from solid materials, the threshold condition as to observability is formulated as a function of the energyEpand the incident angle ϕpof the primary beam. It is shown that for insulators the material's constantn, which appears in the standard formula of the electron range (R) versus energy (Ep) relationshipRΦE pn, can be determined through experimental investigations into observability of the surface. Careful consideration is also given to the effectiveness of the present theoretical a