Electronics Forum | Thu Nov 03 07:43:52 EST 2005 | davef
Questions are: * Is the problem 'wire bonds that don't stick' or 'wire bonds that fall or break off later'? * What materials are you working with? * What is your working time after plasma clean? * What does surface analysis tell you about surface con
Electronics Forum | Tue Apr 15 12:14:02 EDT 2008 | lellis
Contaniminates are always a issue. What chemicals do you use? Do you plasma clean? Are the production personnel wereing finger cots to reduce added contaminates?
Electronics Forum | Fri Sep 10 08:23:34 EDT 2010 | duso02
We have done it before prior to conformal coating a customer's populated board with parylene. They had us do a sample first then conducted testing. No ill effects but it really comes down to the components installed and what they can handle. The surf
Electronics Forum | Mon May 17 13:21:45 EDT 2021 | SMTA-64387881
PWB Bake out or other elevated temperture processes can cause issues with oxidation of that Nickel layer. The gold porosity can vary from batch to batch, but also process changes can contribute. Are you baking the boards or have previous reflow pro
Electronics Forum | Fri Oct 18 06:33:28 EDT 2002 | johnw
Here's one for you lot, dos anyone have a method or a vendor that can clean the ball's of BGA's of oxides to bring them back to 'new' conditions ? I've got a bathc of components that are fairly old and I get some issues with soldering them which I b
Electronics Forum | Thu Nov 03 02:34:46 EST 2005 | Rosewood
We've recently encountered some problems with wire bond strengths. I'm looking for anybody that has had some experience with different types of substrate contamination and methods for cleaning. There is no visible contamination on the gold pads, bu
Electronics Forum | Thu Nov 03 12:48:14 EST 2005 | Rosewood
We have some no sticks, but that is actually a good thing because we have NSD. During process control audits we found that pull strengths to the board dropped off. We build a military application that requires higher bond strenghts. Low pull streg
Electronics Forum | Thu Dec 29 10:47:05 EST 2005 | Chris
The paper Dave posted the link for is great. I have to go back and read it in depth. I can build prototypes by wirebonding to ENIG. I can do it on a manual wirebonder but I don't have the patience to do it on a magazine to magazine automatic machi
Electronics Forum | Tue Jul 25 16:08:52 EDT 2017 | dontfeedphils
I'm currently working on bringing a manual coating process/workcenter online and my QA team is giving me some grief. For background, we're using Humiseal 1B31 thinned with thinner 521, mixed at 1:1 by volume. Spraying through a Binks HVLP with 10 P
Electronics Forum | Tue Aug 14 16:18:48 EDT 2018 | dontfeedphils
A couple of things to try as I just went through this myself. Checkout this link for pointers on plasma cleaning... http://www.nordson.com/~/media/Files/Nordson/march/Papers/The-Effects-of-Plasma-Treatment-Prior-to-Conformal-Coating-NordsonMARCH.p
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