Electronics Forum | Mon Nov 17 14:42:02 EST 2014 | tombstonesmt
Sounds like your snap off profile needs adjustment. More than likely there is paste under the stencil being transferred over to the board. Try adding a cleaning cycle after every board to determine if this is the issue. If the solder balls go away af
Electronics Forum | Wed Mar 17 19:41:15 EST 2004 | Dreamsniper
I'm hit with the above problem and found out that the BGA's themselves have fibres on their solder balls. I have soldered some without having the knowledge of the above fibres and found that the fibres are caught between the PCB pad and the BGA solde
Electronics Forum | Fri May 29 15:17:14 EDT 1998 | Ryan
| Thanks Steve- Here is the whole story: The solder balls are appearing all over, similar to a splatter. They are relatively small. We are using H-Technologies S-HQ no-clean solder paste. The stencil is 6 mil and the boards are running in a ABW
Electronics Forum | Wed Feb 18 12:42:43 EST 2004 | babe
OK, if the sphere of the ball and the paste on the pad are both eutectic, 63/37 then the paste will reflow first causing a drop of the component, after which the spheres will reflow causing a double drop and a good intermettalic. You can see this by
Electronics Forum | Wed Jan 12 13:27:42 EST 2005 | carobin
The two options I see are (not including underfill): 1) Have complete conformal coating coverage of all balls with no webbing in between balls because of CTE mismatches. If all the balls are not coated we see failure in humidity testing. or 2) Sea
Electronics Forum | Tue Aug 25 09:29:59 EDT 1998 | Richard Scarcelli
Would like to know the following information on processing micro bga's: 1) Fine mesh solder paste .vs. tacky flux --- which is best 2) Stencil thickness for solder screen 3) Aperature size for standard pitch balls 4) Which direction is the marke
Electronics Forum | Fri Sep 11 10:52:25 EDT 1998 | Javier Carrera
| Would like to know the following information on processing micro bga's: | 1) Fine mesh solder paste .vs. tacky flux --- which is best | 2) Stencil thickness for solder screen | 3) Aperature size for standard pitch balls | 4) Which direction is
Electronics Forum | Fri Jul 14 14:46:59 EDT 2006 | Gman
Hello Folks, Has anyone come across this fascinating but undesirable surface appearance of BGA balls. I am not sure what it is called but I came across the term Black Island. To me it looks more like a disco ball. Lets just say the solder ball looks
Electronics Forum | Thu Mar 02 21:51:46 EST 2000 | Dave F
Robert: Consider requesting samples of different sized solder balls from a variety of suppliers, solder them to dummy boards, and compare the size of reflowed balls to your spec. Then you could buy based on results. My2� Dave F
Electronics Forum | Thu Mar 02 21:51:46 EST 2000 | Dave F
Robert: Consider requesting samples of different sized solder balls from a variety of suppliers, solder them to dummy boards, and compare the size of reflowed balls to your spec. Then you could buy based on results. My2� Dave F
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