Electronics Forum | Mon Jan 28 08:44:21 EST 2013 | diamondmt
John, In addtion to the cleaning process you may wnat to look at the masking materials you are using as well. Are you using any temporary masking tape? If so, do the dewetted areas coincide? Some of these tapes use a silicone-based adhesive which wi
Electronics Forum | Thu Apr 20 02:27:11 EDT 2017 | pavel_murtishev
Mile, Please tell me more about your soldering process: - Are soldering process parameters the same for all three pins? - Is unsoldered pin connected to thermal heavy copper polygon? - What is your board surface finish? HASL? - Sn/Pb or LF process?
Electronics Forum | Tue May 13 20:48:10 EDT 2008 | davef
Rob On your thermal recipe: Above liquidous for nearly 2 minutes seems to be a scoush long. Not sure you're doing anything positive with things like that. On the article: * SMT Magazine, October, 2002, p24 'Q & A: BGA Dewetting' * "Q: Our manufactu
Electronics Forum | Thu Nov 01 05:30:06 EST 2001 | wbu
This is not about the physical laws but besides contamination, which will actually IMO cause NO WETTING, it is quite vital that the time-limit the flux is active is not exceeded during your reflow process. Depending on your paste/flux you will have a
Electronics Forum | Wed Dec 19 09:56:20 EST 2001 | guicho_v
I'm new in SMT world, and I've got my 1st challenge: I'm having de-wetting issues with a specific IC 160 pins MQFP (six location, failure is random), where one pin has de-wetting (solder reflow OK, and there is evidence of having contact the past and
Electronics Forum | Tue Jul 30 17:51:18 EDT 2002 | davef
Comments are: * Peak at 245�C for 40 sec seems like a very long time. I�d expect the time at 245�C to be 10 to 15 sec. This long time at peak could dewett the pads. * Really, their 2D vision on the printer can verify solder presence? * A thin coat
Electronics Forum | Wed Nov 01 09:01:55 EST 2000 | Thomas Ballhausen
Since your problem has been posted quite some time ago I am eager to know, if you have got any clue. One of my customers recently claimed our 313-PBGA causing problems, as one of its balls (randomly) is almost dewetting. So no evidence is found by x-
Electronics Forum | Fri Sep 09 15:53:22 EDT 2005 | patrickbruneel
If the white residue is from a no-clean flux or no- clean solder flux core you can leave it on the board. (Consult with the flux or cored solder manufacturer) Because after being encapsulated with conformal coating the residue is sealed from humidity
Electronics Forum | Mon Nov 07 06:16:59 EST 2005 | laxman
Hi, We have faced the solderability issue (Dewetting and solder balls)in all the Boards after reflow.When we found this issue we discarded the old paste and started using the new paste then for some hours the solderability found to be O.K. After so
Electronics Forum | Tue Oct 31 08:08:15 EST 2006 | bobsavenger
I'm just looking for some fire-power here. We have a board that when it goes through reflow the first time, everything is fine and has good wetting. When we do the secondary side, one specific part is then Dewetting according to our production oper