In Encounter, we verifyGeometry to find violations of spacing/width/
etc ruls governed by the tech LEF.
When we run the fillNotch command, nearly all of the added metal
structures are placed off grid (see picture offgridfillNotch). The
re****t file does not show off-grid locations, but the DEF file we
write out at the end shows many special nets on the smaller grid. Our
tech LEF specifies the following:
UNITS
DATABASE MICRONS 2000 ;
END UNITS
MANUFACTURINGGRID 0.0050 ;
fillNotch places metal on a 0.0005 grid, and while it reduces
violations shown in the verifyGeometry command it actually increases
DRC violations in Calibre. When we write out a DEF file from
Encounter to im****t into Virtuoso, the following message is printed
out:
Writing DEF file './output/pipeline_fill.def', current time is Thu
Apr 3 08:25:33 2008 ...
unitPerMicron=2000, dbgMicronPerDBU=0.000500, unitPerDBU=1.000000
DEF file './output/pipeline_fill.def' is written, current time is Thu
Apr 3 08:25:34 2008 ...
Suggesting that Encounter uses the grid of 0.0005 for everything.
However, all standard cells and all routed metal are placed on the
correct 0.005 grid - only fillNotch generated metal is placed off-
grid.
Has anyone had this problem before?
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