TY - JOUR
T1 - Estimating Step Heights from Top-Down SEM Images
AU - Arat, Kerim Tugrul
AU - Bolten, Jens
AU - Zonnevylle, Aernout Christiaan
AU - Kruit, Pieter
AU - Hagen, Cornelis Wouter
PY - 2019
Y1 - 2019
N2 - 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 focused on extraction of height information directly from top-down images. In this work, using Monte Carlo simulations, we studied the relation between step height and the emission of secondary electrons (SEs) resulting from exposure with primary electrons at different energies. It is found that part of the SE signal, when scanning over a step edge, is determined by the step height rather than the geometry of the step edge. We present a way to quantify this, arriving at a method to determine the height of structures from top-down SEM images. The method is demonstrated on three different samples using two different SEM tools, and atomic force microscopy is used to measure the step height of the samples. The results obtained are in qualitative agreement with the results from the Monte Carlo simulations.
AB - 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 focused on extraction of height information directly from top-down images. In this work, using Monte Carlo simulations, we studied the relation between step height and the emission of secondary electrons (SEs) resulting from exposure with primary electrons at different energies. It is found that part of the SE signal, when scanning over a step edge, is determined by the step height rather than the geometry of the step edge. We present a way to quantify this, arriving at a method to determine the height of structures from top-down SEM images. The method is demonstrated on three different samples using two different SEM tools, and atomic force microscopy is used to measure the step height of the samples. The results obtained are in qualitative agreement with the results from the Monte Carlo simulations.
KW - 3D topography
KW - height measurement
KW - Monte Carlo simulations
KW - SEM
KW - top-down inspection
UR - http://www.scopus.com/inward/record.url?scp=85065988948&partnerID=8YFLogxK
U2 - 10.1017/S143192761900062X
DO - 10.1017/S143192761900062X
M3 - Article
SN - 1431-9276
VL - 25
SP - 903
EP - 911
JO - Microscopy and Microanalysis
JF - Microscopy and Microanalysis
IS - 4
ER -