Electronics Forum | Wed Nov 01 09:01:55 EST 2000 | Thomas Ballhausen
Since your problem has been posted quite some time ago I am eager to know, if you have got any clue. One of my customers recently claimed our 313-PBGA causing problems, as one of its balls (randomly) is almost dewetting. So no evidence is found by x-
Electronics Forum | Wed Oct 04 16:54:24 EDT 2006 | cw
OK. Thanks!! Lastly, is it the nature of the chemistry that Sn/Pb solder mixed with Pb-free alloy will be getting voids? If so, what's the physic/chemistry behind it?
Electronics Forum | Fri Oct 13 06:44:18 EDT 2006 | Matt Kehoe
Solid Solder Deposit may work www.sipad.com mk
Electronics Forum | Wed Oct 04 16:19:54 EDT 2006 | russ
you may want to try a different MFGR of paste, this does help on many occasions. Russ
Electronics Forum | Wed Oct 04 16:47:25 EDT 2006 | russ
very minimal at very few locations. We do not Xray every board but sample them. I think you will find pretty good results here (not perfect) Russ
Electronics Forum | Thu Oct 05 07:58:05 EDT 2006 | realchunks
I have noticed certain BGAs void more than others. We place about 8 different brands of BGAs and only one brand voids like crazy and we have to adjust for it.
Electronics Forum | Thu Oct 05 16:06:33 EDT 2006 | cw
Thanks! What's your ramp rate?2 - 3C/sec? What's your time above 217C. What's your peak temp?
Electronics Forum | Fri Oct 06 08:24:01 EDT 2006 | inds
CW, make sure your customer is aware of the affect high temp might have on adjacent components on the board. I guess you must have already checked out the rated temperature of all the components on the board
Electronics Forum | Wed Oct 04 14:14:49 EDT 2006 | russ
Change mfgrs of paste OR better yet use pbfree paste, If you are collapsing the balls on the BGA then you are possibly overheating the paste/flux quite a bit. most lead pastes do not like much more than 230 C. I am assuming that you have a decent p
Electronics Forum | Wed Oct 04 16:14:17 EDT 2006 | inds
what is your peak temp.. if you try to go too high say 225-230 deg C there is a fair chance of seeing voids.. depending on your ball size and paste volume you can get a good collapse at temps below 225deg C...
