Jack,
It wouldn't matter where or what the slivers are around, the board shop would be concerned it would float off and land in a bad place. Just for grins, can you let your Soldermask encroach on your vias like we do? On our vias, we let the mask come up on the pads and have a .006" over the finished drill size opening in the mask. This ensures we don't get mask in the holes, but you don't have to worry about slivers around the vias. (If the vias are THAT close, you got other issues too. :-) ) Anyway, hope that helps.
Later...
Scott Decker | Senior Engineer, PCB Design Services CID+ | Electronic Systems Center
COLLINS AEROSPACE
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-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Jack Olson
Sent: Tuesday, February 19, 2019 8:58 AM
To: [log in to unmask]
Subject: [External] [TN] soldermask silvers
In my experience, what a PCB fabricator would consider a sliver would be the strip of soldermask material between RECTANGULAR pads being less than a minimum width.
We got a "DFM report" for a board where minimum distance between ROUND vias is being reported as slivers.Has anyone ever heard of problems with minimum mask material between round, unsoldered vias?
I can't imagine any real-world problems that could cause, but I have an open mind...
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