Electronics Forum | Tue Apr 13 13:01:01 EDT 2004 | arcandspark
These voids only appear in the solder connections that have a (via in pad). The pads that do not have (via in pad) do not have any voids. Profile is 60 seconds above 183 C and peak of 218 C. The BGA is an OMAP lead free,I am using standard eutectic s
Electronics Forum | Thu Oct 08 14:04:04 EDT 1998 | Kris Ewen
Manish, I've seen similar phenomenon when processing CSPs on our cards. In our case, we were placing the components over the opening to in-pad blind vias. Due to poor drilling and plating processes by our board suppliers, volatiles were outgassing
Electronics Forum | Thu Oct 26 10:29:03 EDT 2006 | Mike
First, Voiding under thermal pad is unavoidable(pardon the pun), unless you can find a way to add sufficient amount of solder paste to cover the area, and match that solder volume on your terminal leads. I build HVM qty's of "QFN" components w/ therm
Electronics Forum | Mon Nov 25 22:08:05 EST 2002 | Ben
Thanks for the advise. I got the advise from my solder paste vendor to increase the time above melting point for flux outglassing to escape. I tried but no big help. For the moisture issue, actually I've try to bake both the PCB and components at 12
Electronics Forum | Fri Mar 05 22:49:42 EST 2004 | Bryan She
Hello all, recently,I met a voiding issue in board to BGA ball joints. I've checked so many threads in this forum,but I can't find one which is really useful perhaps.Is there anyone who also met this issue,and then,in the end, succesfully get rid of
Electronics Forum | Sat Mar 06 06:15:14 EST 2004 | Bryan
Thanks Tommy. In fact I've tried many types of profile,but it didn't work.I'll try to make the peak temp. as low as 205C and dwell long as in some threads Dave said.I've tried baking the BGA and PCB before mounting also dindn't work.yes,I've heard th
Electronics Forum | Tue Apr 13 10:30:52 EDT 2004 | Ken
Threre has been speculation as to voiding as a function of solder paste liquiduous vs. ball liquiduous. Gas entrapment is thought to result if one melts before the other (I forget which order). Two profiles may yield different results as determined
Electronics Forum | Sun Dec 28 05:31:59 EST 1997 | Bob Willis
We have a x ray inspection criteria video and poster set which may be of interest check out our home page www.bobwillis.co.uk | | I'd like someone gives me a tip for elemating of voids | | in the mico BGA solder joint and the method of inspection |
Electronics Forum | Thu Oct 05 11:37:15 EDT 2006 | russ
with this design you will have voids, you cannot trap the gas inside of via it has to go somewhere. These vias should be relieved from pad to prevent the scavenging of the paste during reflow. You may try a thicker stencil if you can to allow for t
Electronics Forum | Tue Mar 09 07:51:12 EST 2004 | Bryan
Hello everyone: 1.I use Kester R244 63/37 solder paste. 2.Stencil thickness 6 mil. 3.Springdale Chipset. 4.PCB finish:HASL 5.Profile:Peak temp.:210~220C,time above 183C:60~90 seconds,time between 150~183C 60~90 seconds. 6.Reflow oven:Heller 1800 Voi