Comparison of Different Optimization Techniques in Electron Lens Design

To design electron lens systems, applying a fully automated optimization routine has not yet been feasible, especially for the case where the optimization has many free variables of the lens system, such as all parameters that define the geometry of the lens electrodes and the voltage of each electrode. Hence, the study of the implementation of...

Surface effects in simulations of scanning electron microscopy images

Background: Monte Carlo simulations of scanning electron microscopy (SEM) images ignore most surface effects, such as surface plasmons. Previous experiments have shown that surface plasmons play an important role in the emission of secondary electrons (SEs).Aim: We investigate the influence of incorporating surface plasmons into simulations...

Estimating Step Heights from Top-Down SEM Images

Scanning electron microscopy (SEM) is one of the most common inspection methods in the semiconductor industry and in research labs. To extract the height of structures using SEM images, various techniques have been used, such as tilting a sample, or modifying the SEM tool with extra sources and/or detectors. However, none of these techniques...

Surface effects in simulations of scanning electron microscopy images

We have investigated the contributions of surface effects to Monte Carlo simulations of top-down scanning electron microscopy (SEM) images. The elastic and inelastic scattering mechanisms in typical simulations assume that the electron is deep in the bulk of the material. In this work, we correct the inelastic model for surface effects. We...

Sensitivity of secondary electron yields and SEM images to scattering parameters in MC simulations

In the simulation of secondary electron yields (SEY) and secondary electron microscopy (SEM) images, there is always the question: are we using the correct scattering cross-sections?. The three scattering processes of interest are quasi-elastic phonon scattering, elastic Mott scattering and inelastic scattering using the dielectric function...

Simulation of shotnoise induced side-wall roughness in electron lithography

We have developed a fast three dimensional Monte-Carlo framework for the investigation of shotnoise induced side-wall roughness (SWR) formation. The calculation outline is demonstrated by an example for an exposure of a 100nm thick layer of negative tone resist (NTR) resist on top of an infinitely thick silicon substrate. We use our home...