Electronics Forum | Thu Jul 05 10:45:01 EDT 2001 | dougie
Steven, There is a load of info on this if you check through the archives. Quick pointer though are: Solder balls are caused by paste creeping under the component at placement. The part is placed and the paste is squashed under the component, when t
Electronics Forum | Thu Mar 25 11:30:33 EDT 2010 | Sean
Hello Rajeshwara, If not mistaken, the 25% solder void specification is for BGA...As I I as know, no specification given to mosfet component yet..I think you are right, I need to look at the stencil aperture in order to reduce the air trap underneat
Electronics Forum | Wed Mar 24 10:28:51 EDT 2010 | Sean
Hi all, Anyone used to come across solder void underneath mosfet as shown in the attached file? Will this pose any reliability issue, such as get burnt during functional test? How to over come this problem? As far as I know there is no acceptabl
Electronics Forum | Wed Mar 24 11:09:44 EDT 2010 | rajeshwara
Hello Sir I faced the same problem for QFP in DTH product in India. IPC stated that void should not be more than 25% of solder joint. But this type of void definatly create problem during functional test. Please check the folloeing point... 1.Check t
Electronics Forum | Thu Mar 25 12:34:26 EDT 2010 | bgaguy
the voids will cause a long term relability problem as the part will not be correctly heatsinked. Change your stencil aperature to a "+" sign 15-20 mils wide in the center of the pad. ___________ : | : : | : :----|----: : | : :__
Electronics Forum | Fri Mar 26 03:24:01 EDT 2010 | ravikumarasahitec
Hi, yes we used to see this kind of problem our customer end. This due to stencil aperture opening.these kind of issues we will overcome thorough our stencil process. please contact. ravikumar@asahitec.in
Electronics Forum | Fri Mar 26 09:34:01 EDT 2010 | dyoungquist
What about thermal cycling and/or vibration over the long term? My guess is that with the voids the joint would not be as reliable long term as a joint without the void. Am I thinking correctly?
Electronics Forum | Fri Mar 26 00:57:05 EDT 2010 | 89jeong
Hello Sir. We also have faced a same problem. At that time, we had to repair it because we could not find any solution. But in our experience, the void underneath FET was more severe whenever we used the FET that have been made long time ago. It is
Electronics Forum | Fri Jul 06 18:17:34 EDT 2001 | davef
We find no solder balls after washing our boards. It works GREAT!!! ;-) Probably more to the point, look at "Circuits Assembly" 7/01, p 40, "Eliminating Solder Beads In No-Clean PCBs". "Solder mask type & composition are the greatest contributor t
Electronics Forum | Mon Jul 16 19:27:27 EDT 2001 | eliishee
I have no choice, as per customer's request to remove the solder balls. Can i use water to clean away the solder ball since i'm using RMA solder paste not the water soluable paste.