Imaging of a test object with a trapezoidal profile and large side wall inclinations in a scanning electron microscope in the backscattered electron mode

Abstract

Analysis of imaging of relief pitch structures with trapezoidal profile of relief elements and large side wall inclinations has been carried out in scanning electron microscope in the modes of collection of secondary slow electrons and backscattered electrons. It is shown that the forms of signals of secondary slow electrons and backscattered electrons depend on the structure-element position: close to the pitch-structure edge or far from it. However, the behavior of the signal parameters is independent of the element position. It is demonstrated that the sizes of the parameters of backscattered electron signals characterizing the bottom bases of protrusions and trenches are determined by the true sizes of the bottom bases of the structure elements. At the same time, the sizes of the parameters of the backscattered electron signals that characterize the top bases of protrusions are larger, while those of the trenches are smaller than the sizes determined by the true sizes of the top bases of protrusions and trenches.