Copper plating thickness distribution between the surface and the middle of
the thru hole needs a little more definition, than what you have mentioned.
If the aspect ratio (board thickness/ hole diameter) is 3 or less, meeting
1.0 in the hole and 1.2 on the surface is an acheivable task.
If the aspect ratio is 5 or greater it becomes more challenging.At 10:1
aspect ratio the shop needs to use a hi throw plating bath, and the plating current
must be dropped to as low as 10 ASF with a minimum of 2 hours of plating.
The aspect ratio must be included in the specification of thickness
distribution, between the hole and the surface.
I hope this helps.

Best regards

George Milad
National Accounts Manager for tTchnology
Uyemura International Corporation
240 Town Line Rd
Southigton, CT06489
860 793 4011 (O)
516 901 3874 (cell)
[log in to unmask]

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