Electronics Forum | Mon Jun 18 15:54:25 EDT 2001 | Gil Zweig
For BGA inspection, it is my feeling that he most effective technique a facility can use is the combination of a transmission x-ray system in conjunction with an endoscope (side viewing optical microscope). In using the transmission x-ray inspection
Electronics Forum | Wed Sep 29 04:33:35 EDT 1999 | Earl Moon
| | Hi All, | | Any one experince BGA-chipset warp about 10-15mil after removing | | from PCB? | | FYI, the rework temperature for preheat was 170C from room | | temperature about 30 seconds, & BGA was removed at temperature | | between 190-200C.
Electronics Forum | Thu Nov 21 06:36:30 EST 2002 | Ben
I'm doing SMT of lead-free solder BGA on FR4 Ni-Au PCB. The solder paste I'm using is Sn/Ag/Cu and reflow with peak temp at 240C. I found there are voids(1-2) in almost every solder joint(500 micron in dia) under xray. And the void size is violate th
Electronics Forum | Thu Jan 16 04:02:18 EST 2003 | johnw
The IPC 610 actally conflict's with 7095 which give's a better indication of what's acceptable. I believe that IPC are reviewing both. Motorola did a bunch of work before basically showing that void's aren't that bad up to a certain size, I think pro
Electronics Forum | Thu Sep 16 18:59:14 EDT 2004 | Carol
Thanks Everyone, the information was very useful. We use 7095 as a bible. A-610 6.5.3 doesn't allow for any solder balls not entrapped/attached etc. so we will look again at plugging/tenting both ends of the via. We ran into the problem of the mask
Electronics Forum | Wed Oct 20 14:24:32 EDT 2004 | Steve Gregory
It all depends where the voids are, and that's tough to do with a transmission x-ray. One needs to be able tilt the assembly at 45-degrees during x-ray, so you can get an idea where the void is. Or, you spend some big bucks for an x-ray laminography
Electronics Forum | Wed Oct 20 14:44:24 EDT 2004 | Steve Gregory
It all depends where the voids are, and that's tough to do with a transmission x-ray. One needs to be able tilt the assembly at 45-degrees during x-ray, so you can get an idea where the void is. Or, you spend some big bucks for an x-ray laminography
Electronics Forum | Tue Jul 26 08:20:46 EDT 2005 | Bob R.
All you can do is try it. I did a literature search last year on causes of BGA voiding and came up with a pretty long list, sometimes contradictory. I also discussed it with several paste suppliers. What I came away with is that what aggravates voi
Electronics Forum | Tue Aug 21 20:52:06 EDT 2007 | davef
There is not standard for the force to pull an axial lead from a soldered connection. ".....IPC does not have pull tests in any of its standards, and some reliability experts would prefer to keep it that way, pull tests are commonly used by some lea
Electronics Forum | Sat Jun 21 23:15:07 EDT 2008 | mika
Also keep in mind that the CCGA column length tolerance is at minimum +/- 0.13mm from most part manufactures and they don't collapse in the same way as a BGA, therefore the paste height deposit could be critical in some rare circumstances. Board warp
