Electronics Forum | Mon Sep 30 09:26:04 EDT 2002 | itempea
Russ, first step would be to get IPC-7095 on BGAs. A few notes: There can be voids in solder balls, or at the solder joints to the BGA, or at the solder joints to the PCB. Various sources or reasons can be responsible for these voids. Voids can be
Electronics Forum | Mon Sep 30 09:00:26 EDT 2002 | arcandspark
Russ, I have been reworking BGA's for over five years now and have never been able to remove voids in the solder balls without removing the BGA itself. Your thermal profile can also cause the voids along with a poor solder paste. I have experimented
Electronics Forum | Wed Oct 09 17:44:46 EDT 2002 | alj
I guess you don't use one. Call them and I'm sure they will solve your problems and teach you a little bit about BGA rework profiling... CHEERS!
Electronics Forum | Wed Oct 09 08:55:28 EDT 2002 | russ
okay, so how does the DRS remove voids from BGAs?
Electronics Forum | Wed Oct 23 14:44:58 EDT 2002 | mzaboogie
Hi Ben, IPC610 has a pass/fail of 25% of ball volume. Hope this helps
Electronics Forum | Mon Oct 21 03:52:38 EDT 2002 | Ben
I'm doing lead-free SMT of BGA with 450 micron ball. I found there are lots of voids under xray, there are around 2-3 voids in every balls. It is around 10% of volume ratio. I would like to ask if anyone know there is any standard of acceptable maxim
Electronics Forum | Mon Oct 07 09:05:41 EDT 2002 | russ
thnaks everyone for the the input. I have been noticing that a lot of comments are referring to 230 deg. C and such. has something changed in the industry lately? It has been to my knowledge previously to peak the reflow at 215 or so. I have many B
Electronics Forum | Sat Oct 19 11:48:39 EDT 2002 | davef
Good points, John. Continuing to track on the voiding issue, why remove voids anyhow? * Voids are primarily process indicators. There is experimental evidence that voids retard crack propagation locally around the void on at least on a temporary bas
Electronics Forum | Mon Oct 21 09:09:54 EDT 2002 | Ben
thanks for ur help. i would also like to know the classes is for showing different level of requirement, or for different vertical location of void in joint. coz I heard from my workmate that the range from 9% to 36% is for void at different vertical
Electronics Forum | Tue Oct 08 09:51:10 EDT 2002 | larryk
Russ, I use the R562, it has a longer tack time then the Hm531 and have found no problems with voiding on my BGAs. You may want to evaluate this formula also Larry
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