Electronics Forum | Thu Feb 19 19:34:52 EST 2004 | Tom B.
Jim, There are 2 thoughts to this technology. SMDP (Soldermask Defined Pads) Can achieve more uniform opening of the land, yet as you know Regisration shift of mask can become a problem. Also there has been debate as to whther SMDP cause crack p
Electronics Forum | Fri Oct 07 09:18:39 EDT 2005 | russ
If you're using non-lead free parts then you don't have a pbfree assembly so why worry about marking it anyway? We apply this artwork after the assembly has been completely engineered for lead free. Artwork can be covered up with mask or whatever if
Electronics Forum | Mon Sep 24 22:56:52 EDT 2018 | sarason
IF you are wanting to do to this you are to late in the process. The gold is usually applied after the copper etching of the multilayer sandwich. The edge is extended beyong the board edge and the all pins are connected together with a bussbar. The b
Electronics Forum | Fri Nov 21 18:28:42 EST 2008 | Frank
In the good old days, I've made raw boards at home. Layout the design and then transfer it to a bare copper clad board. Etching it out is the fun part. I grabbed our 9x13 pyrex baking dish from the kitchen. Using metal etching dish doesn't make
Electronics Forum | Fri Jul 07 09:15:23 EDT 2000 | K. Chak
Hi Dave, This particular p/n calls for print&etch for wet process..and the problem occured due to surface contamin. with resist residue resisting copper from etching off. The high pressure nozzle was a problem at developing oper. and it is fixed now
Electronics Forum | Thu Jan 20 21:29:48 EST 2022 | stephendo
Copper gets etched in a photographic manner. ENIG is an additive process. Nickel gets added then gold gets added on top. Therefore it is not a matter of over etching. It is a matter of not enough gold added. The layer of gold ideally is as thin as po
Electronics Forum | Thu Jan 10 11:22:48 EST 2013 | pbarton
Looks to me like under etching of the underlying copper and the gold is just plated to all of the exposed copper surface. Is this characteristic the same on all solderable pads? You will not be able to remove this gold.
Electronics Forum | Mon Oct 06 15:04:25 EDT 2008 | hussman
Brick (if that is your real name), Placement machines use centroid data to place parts. Generally this is derived from the "copper" that is etched on the board. Thus why we use the fiducials for alaignment. During board manufacturing, holes are d
Electronics Forum | Fri Aug 22 14:24:54 EDT 2008 | boardhouse
Paul, I would do two things, eval whole lot for any etching issues as shown above and scrap and two I would have your copper thickness checked, my guess your copper plating will be low. Check plating thickness in Via holes - if less then 8/10th's r
Electronics Forum | Tue Aug 15 17:00:52 EDT 2006 | Board House
Bake your solder mask and then solder coat. If you are going to put an immersion finish like Osp, gold, tin or silver you would have to do a Micro etch to clean the copper prior to placing the surface finish. Regards, Board House
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