[comp.lsi.cad] How can I place vias over contacts in magic?

ge@mcnc.org (George Entenman) (09/13/90)

We have a MAGIC problem that perhaps someone has solved and
would be willing to share a fix.

Our latest technology has a third level of metal, so we've added
a ninth plane and worked out the colors and stipples.

If I put via2 (connecting m2 to m3) in the metal2 plane, I can
draw via2 over regular contacts (connecting the active plane to
m1) but not over via1s (connecting m1 to m2): whenever via2 is
painted over via1 (or vice-versa), the latter gets replaced.
All that is good.

The problem is with the contact section of the tech file.  For
many reasons I need to add the line

   via2 m2 m3

line to the contact section.  But when I put the above line in,
via2 can no longer be placed over regular contacts: the contact
is deleted when via2 is drawn over it.

Any help would be appreciated.


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