Modeling of electron backscattering from topographic marks

The generation of the backscattered electron (BSE) contrast from topographic marks is investigated applying single-scattering and diffusion theories of electron backscattering. It is found that a combined model, which accounts for both single-scattering and diffusion fractions of electron backscattering, has the potential to explain our recent experimental results. The combined model predicts that the BSE contrast from an isolated topographic mark (e.g., V groove, trench) is a universal function of a dimensionless parameter, the ratio of the mark depth to the full electron range. This is also confirmed by our experimental results. Our model reveals the basic trends for the BSE contrast improvement and is capable of predicting the optimal conditions for any topographic mark detection.