We have developed a highly integrated method of mask and silicon metrology. The aim of this integration
is evaluating the performance of the silicon corresponding to Hotspot on a mask. It can use the mask
shape of a large field, besides. The method adopts a metrology management system based on DBM (Design
Based Metrology). This is the high accurate contouring created by an edge detection algorithm used in mask
CD-SEM and silicon CD-SEM. Currently, as semiconductor manufacture moves towards even smaller
feature size, this necessitates more aggressive optical proximity correction (OPC) to drive the
super-resolution technology (RET). In other words, there is a trade-off between highly precise RET and
mask manufacture, and this has a big impact on the semiconductor market that centers on the mask
business. As an optimal solution to these issues, we provide a DFM solution that extracts 2-dimensional
data for a more realistic and error-free simulation by reproducing accurately the contour of the actual
mask, in addition to the simulation results from the mask data. On the other hand, there is roughness in
the silicon form made from a mass-production line. Moreover, there is variation in the silicon form. For
this reason, quantification of silicon form is important, in order to estimate the performance of a pattern.
In order to quantify, the same form is equalized in two dimensions. And the method of evaluating based
on the form is popular. In this study, we conducted experiments for averaging method of the pattern
(Measurement Based Contouring) as two-dimensional mask and silicon evaluation technique. That is,
observation of the identical position of a mask and a silicon was considered. The result proved its
detection accuracy and reliability of variability on two-dimensional pattern (mask and silicon) and is
adaptable to following fields of mask quality management.
•Discrimination of nuisance defects for fine pattern.
•Determination of two-dimensional variability of pattern.
•Verification of the performance of the pattern of various kinds of Hotspots.
In this report, we introduce the experimental results and the application. We expect that the mask
measurement and the shape control on mask production will make a huge contribution to mask
yield-enhancement and that the DFM solution for mask quality control process will become much more important technology than ever. It is very important to observe the form of the same location of Design,
Mask, and Silicon in such a viewpoint. And we report it about algorithm of the image composition in
Large Field.
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