Electronics Forum | Thu May 13 18:36:55 EDT 1999 | Andrew Wulff
| | On 1.27mm (0.050 inches) Standard Ball Grid Array's. | | The ball size diameter starts at approximately 0.025 inches. | | | | If the ball size decreases to 0.012 inches (due to the solder flowing down a via) is the solder connection reliable? |
Electronics Forum | Fri Feb 13 11:19:07 EST 2004 | Evtimov
Hi Bryan The answer is in the paste compozition. Balls of the BGA are usually made by eutetic solder paste.
Electronics Forum | Thu Feb 12 10:19:46 EST 2004 | Bryan
Hi all, These days our customer asks us to figure out ,during reflow,the BGA ball and solder paste,which will first melt? I think it's very hard to get the rusult.coz I think it'll vary at diffrent part of the BGA,and how can this affect the perf
Electronics Forum | Fri Feb 13 11:46:23 EST 2004 | Jack
Is your customer trying to reduce voiding? If the device is using Sn90 / Pb10 and the paste is Sn63/Pb37 the board will melt first. However, if both solders are 183C eutectic, it's a tossup? PCB design, copper weight, bga type (pbga, micro bga, Tbg
Electronics Forum | Fri Feb 27 11:33:32 EST 2004 | Bryan
Very strange question,but interesting.Is there anyone who have conducted any experiments to figure out the results?I made a profile board,one thermal couple on pad and other one drilled into the ball of BGA.the 2 points are perpendicular to conveyor
Electronics Forum | Wed May 12 20:32:14 EDT 1999 | Earl Moon
| Earl | | you posted a message on 1-14-99 about converting to VOC free flux. Have you completed your evaluation? Could I get a copy of any data supporting your conversion to VOC free? | | Thanks | | WDR | | WDR, We are awaiting the latest dat
Electronics Forum | Tue Feb 17 04:52:13 EST 2004 | John W
There's normally a number of reasons people want to know what melts 1st, 1 - to see if you know, 2 voiding issues - whole can of worms 3 device alignment. One of our collegues has said that most balls are Eutectic, that's in fact not totally correct.
Electronics Forum | Fri Jul 15 16:50:04 EDT 2005 | davef
Few of us here on SMTnet fabricate our bare boards. Most of us are assemblers. So, the solderability of the connections of our boards is a BIG issue with us. Our suppliers protect the solderability of the copper by coating the copper to limit the
Electronics Forum | Thu Jun 23 23:58:03 EDT 2011 | jamessunderland
Just want to ask. What is the effect of dull gold surface on solderability? When I made a test run with several pieces containing dull gold defect on the pad(of varying levels), I found that components can still stick to the pad with good amount o
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
