We leave the non-functional pads on inner signal layers for dimensional
stability (52 layer, 3 subs, 5 step sequential lam) and remove the
non-functionals from the planes. This allows the anti-pad on the plane
layers to be swelled relative to the drill which in turn gives more
registration tolerance in a stripline environment so as to not leave the
traces without there reference. Inner pad tear-out has not been an
issue, although good hole walls and plating is.

-Shawn

Jack Olson wrote:
>
> It seems that most fabrication vendors prefer to remove the unconnected pads
> from inner-layers, in fact we do it for them before we send out the gerbers.
>
> But I thought I overheard Gary Ferrari say there was some test results that
> showed the board to be more reliable with all pads included, but I don't
> know where to find it or who did the testing.
>
> Does anyone know if it is significant enough to re-evaluate our process?
>
> Jack
>

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