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| From [log in to unmask] Tue Feb 13 11: |
15:11 1996 |
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I was wondering the same thing. (However, I have seen "landless" holes
produced off shore that had 5 track density.<On the outerlayers>)
I haven't seen this here. And Norm's completely correct, inhibiting
the copper plating solution flow thru the hole would produce a less
than desirable plating deposit.
Groovy
______________________________ Reply Separator _________________________________
Subject: Re: Non-Functional Pads
Author: [log in to unmask] at SMTPLINK-HADCO
Date: 2/10/96 10:48 AM
Greg,
Do not EVER remove the lands from the outer layer. The pads are
necessary during the plating process. Removing pads will prevent
plating solution from getting in the holes. Even with a dot pattern
to allow plating, the quality of the plating will be horrible and non-
reliable. This is one of the main reasons for a minimum annular ring
requirement.
With good process control of plating, normal stresses will not effect
hole reliability
Regards,
Norm Einarson
Printed Circuit Technology
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