Progress towards quantitative dopant profiling in the SEM

Abstract

Dopant contrast from secondary electron (SE) imaging is essentially determined by the local electronic band structure at the surface of the solid specimen being analysed in the scanning electron microscope (SEM). To study dopant contrast mechanisms on inhomogeneously doped semiconductors, we have developed a quantitative model by using a numerical method based on a combination of finite-element carrier and potential modelling and Monte Carlo simulation of SE emission and contrast detection. This combined model enables distinction between the effects of specimen internal fields (surface band-bending), microscopic external fields (patch fields) and any macroscopic external fields applied in the SEM. © 2010 IOP Publishing Ltd.