Electronics Forum | Fri Apr 29 14:16:16 EDT 2011 | ppcbs
Below is the long explanation. This defect is most commonly found with BGA components, but can arrise with all components. I see it happening more now with lead free boards that are being assembled with a no clean flux. Best short term remedy is t
Electronics Forum | Tue Apr 17 10:17:10 EDT 2001 | genny
Hi, ENIG finish is the same reason I came to this forum for the first time a few months ago. I found a bunch of useful information by searching the archives. Check it out. ENIG has some good properties like flatness, and the process control has i
Electronics Forum | Mon Oct 25 17:50:46 EDT 2004 | Mike
I work for a PCB Manufacture and I am looking for info on BGA Pull test or strenght test. I have a CM that is experiencing bga's with some weak joints. they are telling me that when they do their pull test the joints are breaking at the nickel inste
Electronics Forum | Mon Oct 25 21:49:14 EDT 2004 | davef
First, any results of pull or shear tests are unscientific at best. [We pop our BGA from boards with, appropriately enough, a beverage can opener.] Second, we have no have problems with your ENIG specification. Third, as with your customer, we'd e
Electronics Forum | Mon Jul 26 09:19:57 EDT 2004 | davef
Both imm silver and ENIG provide flat surfaces that are better for fine pitch placement and reflow than HASL. We know of nothing that makes BGA locations different than other locations when using ENIG solderability protection. More broadly, the pri
Electronics Forum | Fri Feb 22 08:26:51 EST 2002 | davef
You are correct. The gold dissolves in the solder. The gold is meant to protect the nickel from oxidizing, so that you can solder to the nickel. Obviously that didn�t work as planned. Your background information is very sparse. Two things come
Electronics Forum | Thu Apr 24 20:39:01 EDT 2003 | davef
3NaH2PO3 + H2SO4 + 2H2 + Ni^0 Potassium is co-deposited with the nickel, as follows: H2PO2^- + Hads => H2O + OH^- + P 3H2PO2^- + P => H2PO3^- + H2O + 2OH^- Nick Biunno gives a very short, over simplified summary: "Everybody looks at the nickel, b
Electronics Forum | Fri Dec 29 16:05:56 EST 2000 | Dave F
I don't know how I ended-up reading a current trade journal, when I have a stack of intentions behind my desk a foot and a half tall, leaning like a paper Tower of Pisa threatening to avalanche itself onto the underfill materials study, a meager one
Electronics Forum | Mon Feb 14 12:19:32 EST 2000 | Dave F
Dean: I associate black plague as an immersion gold process problem (although I could easily be wrong): Everybody looks at the nickel, but the cause turns out to be the immersion gold is too aggressive. The immersion gold works by corroding the nic
Electronics Forum | Thu Dec 14 12:18:01 EST 2000 | genny
Hello all, Our company has always used HASL finish on our products. Recently however, we have a had a problem on a couple of boards that I have been told cannot be avoided with HASL, and we should switch to ENIG(electroless nickel immersion gold).