Electronics Forum | Wed Aug 23 17:22:39 EDT 2023 | markhoch
I'm curious what you use for PCB Support. Are you using a dedicated support plate or are you using magnetic pins or some type of Grid-Lock system?
Electronics Forum | Wed Aug 23 17:43:42 EDT 2023 | calebcsmt
Support bars, so essentially the board is sitting ontop of beams that make a table. Fully supported with no soft spots
Electronics Forum | Tue Nov 27 14:24:13 EST 2001 | mparker
Short term fixes can be: have the vias "plugged" with solder by the fab house. This works if your fab is HASL finish. Tent the vias with solder mask, top side only. You may get a flux entrapment issue in the vias with this manner. Long term fix can
Electronics Forum | Mon Jan 13 18:22:55 EST 2003 | davef
100 sec) and decrease reflow temp to 205C. * Understand that voids are primarily process indicators. There is experimental evidence that voids retard crack propagation locally around the void on a temporary basis. There is no standard, IPC or otherw
Electronics Forum | Wed Oct 03 17:06:43 EDT 2001 | davef
Yes, moisture entrapment causes solder shorts 80% of the time. Cracks occur bottom side of the BGA. Use an acoustic microscope to find the cracks. So, what makes you think your BGA are blowing-off steam? I posted a vid on SMTnet that showed the b
Electronics Forum | Wed Jul 28 17:46:13 EDT 2004 | Steve Stach
Both temperature and humidity can cause solder paste to behave in a way to cause these formations. Temperature can cause slumping, slumping spreads out the paste, upon reflow perimeter paste does not join the bulk, and because of insuffient oxide
Electronics Forum | Wed Mar 11 18:28:03 EDT 2015 | gregoryyork
Hi its undercured solder resist which leaves a clear waxy/oily residue and can be seen as brown tar/oil in the molten solder wave. This also causes MicroSolder Balling and some snail trails of solder pick up and worst case bridging and peeling resist
Electronics Forum | Mon Jan 10 16:58:48 EST 2011 | piter
Hi Ripal it seems that you have problem with compatibility of alloy and quality of solder balls. First check solder alloy form BGA balls what is it?(SAC105,SAC305, etc.) what type of solder paste you use?? third thing is what type of finishing you h
Electronics Forum | Sat Feb 19 09:11:36 EST 2005 | davef
Currently, we see lead-free solderballs on BGA. The issue for us is determining the reliability of these components when using leaded solder. Most solder materials manufacturers supply lead-free solder balls. Check with your current solder paste s
Electronics Forum | Tue Feb 13 07:26:26 EST 2001 | doctord
Bill, I can give you suggestions. First and foremost. Print a board and look under a microscope. Are you printing exactly on the pads? If you print on the mask, no matter how good we got the profile, no matter what paste we would get solder balls. Mo
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