Non-silicon semiconductor materials have become more and more important in the
development and implementation of advanced technology nodes. The most prominent
of these materials are silicon-germanium compounds, because they facilitate
performance tuning via stress engineering, and they are reasonably compatible
with silicon-based technology. Therefore accurate simulation modules which can
deal with these silicon-germanium compound materials are necessary. One of the
most critical process modules is ion implantation, which requires, on the one
hand, accurate implantation tables for the analytical simulation analysis of ion
implantation and, on the other hand, advanced and well-calibrated Monte-Carlo
ion implantation simulation capabilities. Therefore a Monte-Carlo ion
implantation simulation module for the accurate simulation of ion implantation
into silicon-germanium compound semiconductor material has been developed. Since
quantitatively predictive capabilities are a must for a Monte-Carlo ion
implantation simulator, extensive evaluation and calibration of the simulation
tool on the basis of experimental results is inevitable. For this purpose, a set
of specifically selected experiments has been developed and carried out. On the
basis of these experiments, the independent analysis of the various effects
which characterize the implantation behavior (channeling, damage accumulation)
has been feasible. The experimental set-up is clearly distinguishable from usual
industrial experimental analysis, which mainly focuses on typical fabrication
conditions. Nevertheless, in order to ensure the applicability of the
calibration to semiconductor technology requirements, usual silicon wafers with
epitaxially grown silicon-germanium layers with various, but typical, germanium
contents were used for the experiments. However, not only the influence of the
compound composition, but also the influence of epitaxially induced stress on
the ion implantation behavior, was investigated. As a side effect of such a
comprehensive experimental analysis, implantation tables for analytical ion
implantation simulation modules can also be calculated.
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