Electronics Forum | Tue Mar 09 22:20:16 EST 2004 | Ken
Is this a PBGA? If yes. run a flat steel rule or edge across the top of the PBGA. Is it flat or cupped? Is this a TBGA (super bga). I have seen issues with a suppliers heat spreader design that actually will deflect the corners down and raise the
Electronics Forum | Thu Sep 29 19:18:24 EDT 2005 | HLy
Hi, I noticed that the solder joints on my BGAs end up with a lot of wrinkles after reflow. See picture at: http://pstr-r02.ygpweb.aol.com/data/pictures/02/01A/17/DD/E3/9E/n8BhepQLFDs6GMSwaRNxPCTWR5NdpUJZ0300.jpg Does anybody have any ideas what cau
Electronics Forum | Sat Dec 10 19:10:17 EST 2005 | mika
Most of the chip; res & caps are already lead-free or RoHS compliant and you most certainly already solder them in your regular leaded reflow process. However, there are a few more component packages except from BGA:s that are NOT backwards compatib
Electronics Forum | Tue Mar 28 17:10:25 EST 2006 | mikecollier
I unfortunately cannot post any photos, the unit in question is classified. And, as far as my comment that the BGA profile can be manipulated, if an engineer is also working the process with one of the operators, they can override the profile at any
Electronics Forum | Thu Dec 07 07:36:15 EST 2006 | callckq
Hi Davef, The BGA pad is with ENIG finish, the PCB pad is with immersion silver and the solder paste is with SAC type. I already checked, the solder paste Cu is just 0.5%..Hence, I am guessing that copper migration is from PCB pad. No way it is fr
Electronics Forum | Sun Feb 25 11:59:33 EST 2007 | stepheniii
Just make sure you keep the half done assemblies in dry storage or do the second reflow within the time dictated by the BGAs MSD rating level. Maybe this time you did the second side with a very short wait because you were anxious about the results
Electronics Forum | Wed Mar 12 23:00:10 EDT 2008 | davef
You can say: The pad was lifted after reflow and prior to the dye and pry failure analysis. When we see lifted pads, we think: * That's a good solder connection * Either it took a lot of force to lift that pad or the fabrication of the board in the
Electronics Forum | Thu May 01 16:27:04 EDT 2008 | chrisawallace
As Mark stated in a different reply, we also send our Pb-free BGA's out to be re-balled with SnPb paste so that we don't have to elevate the reflow temperatures. You have to be careful regarding the individual components on your boards as although m
Electronics Forum | Wed Aug 27 08:46:14 EDT 2008 | vladig
Hi Sean, It's an old problem with no definitive cure for now. However, there are a couple of things to look for. First of all the location(s) of HoP. If it was due to the componetn warpage, then it would be most probably in the middle and it should
Electronics Forum | Fri Mar 04 01:08:19 EST 2011 | kemasta
Thanks davef Bridging:- There is no heat sink on the BGA, the heat sink will be fix after relow. I do believe paste had something to do with it, but currently this defect didn't appear so oftenly, so we think that the main root cause is not from the
