In a message dated 10/12/99 5:51:38 PM Central Daylight Time, [log in to unmask]
writes:

> On one of our product, we have found that one of the inner layer has
>  misregistration.
>
>  Do you see any quality/ long term reliability problem associated with inner
>  layer misregistration? Our requirement was to have a 1 mil minimum annular
>  ring on all inner layers. What is the risk cum liability of accepting those
>  boards knowing that they are misregistered.
>
>  Misregistration occurred at 1mm BGA where the finished hole diameter is 9
>  mil on a 20 mil pads.
>
>  re,
>  ken patel

Ken,

As one who is learning, and one who has experienced some bare board problems
recently, I would like to ask a question or two to clarify...

1. Are you seeing break-out? No complete anular ring at all, just partial?

2. What is the laminate material of the board? How many layers? Does this
mis-registration violate any other minimum lines and spaces standards? Or is
it just a problem of incomplete anular pads?

Thanks,

-Steve Gregory-

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