Electronics Forum | Tue Feb 05 09:19:27 EST 2002 | Carol Stirling
Would someone be able to direct me to information on residual BGA stress please? I've been told that mounting the BGA involves residual stress to the solder balls due to different expansion characteristics of the BGA versus the board at the moment of
Electronics Forum | Tue Jun 04 15:58:06 EDT 2002 | Hussman69
Hmmm... I know the Vitronics oven had bigger motors on em', but I don't think they're blowing molten solder balls around. You did say you changed your profile and stencil designs, which helped, but didn't exactly state what ya did. I believe this
Electronics Forum | Wed Jul 31 12:47:34 EDT 2002 | mzaboogie
Hi Patrick, We are using AIM 266-3. The topside preheat temp is approx 100 degrees C although we have played with that number both up and down. Raising the temp leaves a white residue, lowering the temp (below about 90 degrees) and the solder balls
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 | Tue Oct 22 13:11:07 EDT 2002 | slthomas
After considerable hemming and hawing, we decided to drop the bomb on 'em....give us ORL0 (which we use here) AND no bottom side solder balls or belly up to the bar with some favorable Appendix B test results on their preferred flux. As usual, Mr. F
Electronics Forum | Tue Nov 05 09:21:18 EST 2002 | stefwitt
After all, you may want to consider a Flip Chip process. The chips are bumped with tiny solder balls while still on the wafer. You may present the bumped chips in Gel Pack, trays or Surftape to your Pick $ Place machine ( if capable for Flip Chip pl
Electronics Forum | Thu Jul 03 15:29:46 EDT 2003 | bpan
Hello Jim, We build boards that have traces under the parts all the time. For the most part, we have no problems but on one product we have an 0805 that bridges 2 traces with a very tight seperation and if any solder smears (under the part)we can and
Electronics Forum | Tue Jul 20 02:36:03 EDT 2004 | yukim
Hi, The solder paste is SE5-M951X-9. Comparing with the previous one we used, we are having much more tombstoning problems. The reflow profile is such as: room temp to 140C: 85~95 sec 140 to 170 C: 80 sec 170 to 200 C: 20 ~ 23 sec Above 200 C: 44 ~
Electronics Forum | Mon Jun 13 09:23:54 EDT 2005 | russ
I agree with Dave on the Water soluble process for this part. It is interesting that I have yet to find a Water Soluble for lead free that works. I have experienced a lot of problems with the flux on these pastes, wetting, solder balls, etc... kind
Electronics Forum | Tue Jun 28 11:31:23 EDT 2005 | kennyg
Anyone know of a maximum solder overprint formula? I need to overprint a 0.011" wide aperture but want to go out to 0.050" overprint. This seems extreme, but necessary as I can't go out in width due to numerous issues. It seems like one could come
