Electronics Forum | Sun Jan 14 16:35:48 EST 2007 | Austin
I have several boards built at various CM's. We have prototype builds with some JTAG failures on BGA's (1-3 failures with qty 3, 1500 pin BGA's). CM's always claim reflow profiles look good. X-ray does not show bridges and they claim it looks good, b
Electronics Forum | Mon Feb 12 01:09:49 EST 2007 | Wayne
I think the best way is to the following: - to use the low temp solder paste, or - asks semi-con use low temp solder sphere to make BGA
Electronics Forum | Tue Nov 10 07:35:04 EST 2009 | scottp
Step 1 is to find out what kind of opens you're getting through a cross-section or die & pry. Are they head in pillow, brittle fracture at the intermetallic, bulk solder cracks, ball separation from interposer? Without some basic failure analysis a
Electronics Forum | Wed May 02 11:00:46 EDT 2007 | bartlozie
to get a 0-defect layout, OEM and CM have to work together, If you know what connections (balls) are the problem ones, let me know, and send me the gerber-layers + solderpaste layer, so we can see if the problem is design related or if you CM realy
Electronics Forum | Mon Jan 15 11:21:48 EST 2007 | davef
Contractor mantra: * Profile is good * Boards are bad On profiles, the key question is: where did you take the profile? We�d guess cracked connections are giving the intermittent test results when pressing on the components. You use acoustic micro
Electronics Forum | Tue Jan 23 10:22:27 EST 2007 | Peter W.
Hello, maybe you are experiencing the so called "head in pillow" defect. It is especially critical for larger BGA. The defect comes from the deformation during reflow of the BGA, so that some of the balls are lifted and have no contact during liquid
Electronics Forum | Thu Nov 12 04:35:13 EST 2009 | sachu_70
You can certainly venture out to the nearest lab for in-depth analyses. But since you mention 2-3% defectives in a batch, there is much you can do in-house as well. Measure the height of your solder paste deposit (in zero print gap condition)across a
Electronics Forum | Sun Jan 28 13:26:27 EST 2007 | Sweet Old Bob
Okay you CM haters I don't see anything about the design of the board, other than OSP which is strike one. What is the board size? What is the board thickness? Where is the BGA located on the board? What is your ball to pad ratio? What is your aspect
Electronics Forum | Tue Jan 30 03:44:17 EST 2007 | frank63
Thank you for feedback and comment. We are trying this again, increasement of solder temp to reach 210-215 peak temp. This is also our norml guideline, but in the past the colleagues had observed problem with that PCB, so reduced it. I let you kno
Electronics Forum | Tue Sep 13 09:50:06 EDT 2005 | slthomas
"I think the best is to make sure the oven profile and other factors are set up so as to avoid any opens in the first place." I think you answered your own question. The difficulty (from my limited experience, anyway) in adequately qualifying your
