Electronics Forum | Wed Jul 07 00:28:59 EDT 1999 | Scott Cook
| Q #1) Is it more reliable to have the mask tent over the vias or risk getting vias half filled with solder? These are vias with an .020" hole and .040" or .050" pad. John, It depends......mainly on the via size. Tenting works on smaller vias. Tent
Electronics Forum | Wed Jul 07 13:41:42 EDT 1999 | Dave F
snip | | If you go for plugging be sure you have a protrusion spec that you can live with. This often results in little bumps of epoxy that can interfere with component placement. For us, tenting .015 vias usually gets us about 80% coverage from
Electronics Forum | Fri Aug 16 10:00:03 EDT 2002 | davef
You have a very bad situation. It�s tough for the gas, flux material, er whatever to escape when the BGA is sitting on top of it and the blind via is blocking it from the other side. Obviously the vias should have been: * Placed on the edge of the
Electronics Forum | Thu Aug 25 10:17:48 EDT 2005 | davef
Send the pic to dave5252 at hotmail.com [you can't send pic through the SMTnet email thing] For more on via plugging, tenting, capping ... look here: http://www.merix.com/technology.php?section=processes&page=pdf/Via_Fill_Plug.pdf Something, a voi
Electronics Forum | Wed Aug 24 08:50:59 EDT 2005 | davef
First, while black pad can be a problem with poorly controlled electroless gold [search SMTnet Archives for background], it is not a suffiecient reason to use electrolytic. It's the reason the supplier should fix their electroless gold process. Se
Electronics Forum | Thu Feb 07 11:59:48 EST 2002 | Ron Costa
When double sided BGA's are used on an .062 FR4 10 layer board should via's be plugged and tented? The CACHE chips being used are PBGA's 1.27mm pitch. The pad size is .030 and the finished via dia. is .010. This is a dogbone type pad and via design.
Electronics Forum | Wed Jan 05 12:48:44 EST 2000 | Dave F
Millerin: You are generally correct about plugging and over plating vias, but in Michaels case, the via is blind. Plugging would trap air between the bottom of the via and the plug material, causing an air pocket. When heated to soldering temperat
Electronics Forum | Tue Jun 15 22:31:06 EDT 2010 | Mag10
Depending on the how you plug the via, the void level can significantly affected. If you have via plugged from the bottom side; i.e. opposite side of the component, you will see alot of void due to entrapped air in the via hole. I found work best wh
Electronics Forum | Mon Jul 26 12:55:34 EDT 1999 | M.L
Presently protos of micro-bgas (80i/o) pitch .030/.031 12BGA per assembly The board is a (.062, 4 layers) FR-4 using Dry film Pads .014inch Vias within footprint .020inch Vias to be filled by bottom side(solder side) only .030in dia. Force via plugg
Electronics Forum | Thu Feb 15 12:32:14 EST 2007 | Eric D
one of my customer areworried about the flux risidue in the blind vias, or if the plug the vias and there is air trapped the plug will blow during our process. Appreciate for your response
