TechNet,

I'm sure there are several aspects to consider in controlling warp and
twist in a
PWB.  From my experience I have always found balancing construction as closely
as possible and keeping the copper distribution as equal as possible to be
a big
benefit.  I can't say this will always work, but I can say that for each
instance of
warp and twist I had to correct, adding hatch or distributing
vias/pth/copper as
evenly as possible has always made it better and usually fixed the
problem.  As
far as the type of FR4/weave/resin material, I have always relied on the PWB
fabricator to select the best stackup to meet my requirements and
specifications.

DT




At 08:51 AM 12/2/99 -0600, you wrote:
>Hey Ya'll,
>       The subject has come up....why add copper to signal layers in a
>multilayer board if it has no electrical function?
>I am in the habit of filling open areas with copper to prevent board
>warpage. This does work, doesn't it?
>Should copper fill be solid or hatched? Or does it matter?
>
>Help a designer/Help an engineer.
>
>Thanks,
>Barbara J. Burcham, CID
>PCB Designer
>Fairfield Industries
>Sugar Land, TX 77478
>281-275-7687 Work
>281-275-7550 Fax
>[log in to unmask]
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