KLA Tencor P-16+, User Manual

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0142530-000 AB KLA-Tencor Confidential 6-45
3/13/09
KLA-Tencor P-16+ / P-6 User’s Guide Sequence Recipe and Data - Groping with Pattern Recognition (P-16+ Only)
4.
Choose the number of layers from the menu. (See Figure 6.36 . For information
on the groping layers see Table 6.12
.)
5. Set the Lowest Match Score (%) by highlighting the current percentage and
entering the new one. (See
Figure 6.36 . For information on match scores see
Table 6.12
.)
6.
Set the Minimum Score to Stop Groping (%) by highlighting the current
percentage and entering the new one. (See
Figure 6.36 . For information on
match scores see Table 6.12
.)
7. Edit the fields by using the parameters described in Table 6.12 .
Table 6.12 Groping Parameters
Parameter Description
Number of Groping
Retry Layers This parameter controls how much of the area around the
deskew site is searched for the pattern. Each layer consists of
a square area constructed by evenly surrounding the deskew
site with squares the size of the camera field of view. (See
Figure 6.37 ).
Figure 6.37 Groping Retry Layers
Available choices are:
Š None (the default)
Š 1 (8 Sites)
Š 2 (24 Sites))
NOTE: It takes 10 s to move the stage, null the
stylus, and search one such area; 8 search sites
(1 layer of retry) takes as long as 90 s; and 24
sites (2 layers) takes as long as 250 s, and so
on.
First, the deskew site field of view is searched. If the pattern is
not found, the stage moves to one corner of the next layer
and searches the field of view there. This continues until the
pattern is found or until all search sites have been examined.
If the pattern is still not found, the stage moves to one corner
of the next layer and continues.
2nd Retry Layer
searches for
24 more square areas 1st Retry Layer
searches for 8
more square
areas
3rd Retry Layer searches for 48 more squares; 4th Retry Layer
searches for 80 more squares. It stops after the 4th try.
Groping
disabled
searches only
camera field of
view