Electronics Forum | Wed Sep 11 16:57:04 EDT 2002 | bigwop
I've seen this problem caused by the cool down. > On a 7 zone oven I made a profile to peak at zone > 5 to give some semblance of control to the cool > down. The component can develope a big delta T, > because of the difference of materials Che
Electronics Forum | Tue Sep 07 22:15:26 EDT 1999 | NAZEEH CHAUDRY
| | | I have a zevatech 570 and 560 my boss want to place bga.s with these machines, Ive told him he needs to ugrade to newer machines. Zevatech say "no problem our machine are number 1". | | | these machines dont even offer bga selections. These mac
Electronics Forum | Wed Jan 16 22:57:52 EST 2008 | amarpreet41
Any one got experience on handling solder bridging under one corner of BGA?
Electronics Forum | Wed Dec 06 21:59:37 EST 2006 | SMTrework
Hello, we rework BGA packages that come back from the field. I've seen on occasion a black and or red "epoxy" substance from the manufacturer on the corner of some board's BGA chips that I imagine are applied to increase corner bond of the chip to th
Electronics Forum | Wed Dec 06 22:35:05 EST 2006 | davef
Questions are: * When you say, "corner of some board's BGA chips", is it on the top of the package or between the board and the bottom of the package? * If between the board and the bottom of the package, does it span the distance between the board a
Electronics Forum | Tue Jan 22 22:23:48 EST 2008 | amarpreet41
Thanks, I am working on to prevent solder bridging. Tried fine tuning reflow profile, solder printing looks fine. Any further ideas??
Electronics Forum | Wed Jan 23 18:15:33 EST 2008 | gsala
Hi, are you dealing with Leaded or Lead Free P-BGA ? soldering by Lead or Lead Free paste ? Any way, some time, bridges can be caused by moisture entrapped in the BGA body. Make sure if is respected the correct MSL's allowed flore exposure time, ot
Electronics Forum | Thu Dec 07 12:18:28 EST 2006 | realchunks
It may be for a double sided reflow process. Yes, some people do put the BGA on first. I know this first hand.
Electronics Forum | Thu Dec 07 14:17:03 EST 2006 | russ
I would bet that it is a SMT adhesive used to ensure that the BGA does not move during a secoindary reflow prcess. this glue is easily removed with a soldering iron. Russ
Electronics Forum | Wed Jan 23 19:44:45 EST 2008 | hegemon
In addition to the pre-emptive steps mentioned above, in my experience there are certain BGA package designs that seem more prone to that corner bridging. I have seen some packages that will essentially "curl" down at one corner as the package begin
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