Electronics Forum | Wed Dec 27 17:13:28 EST 2000 | John K.
As part of an Intel erratum, they changed their BGA coplanarity spec from .006" to .008". The package is 23 X 23 partial array, .050"(1.27) pitch, 1.220"(31) square. We apply paste onto BGA pads with a 6-mil stencil. From a process perspective, sh
Electronics Forum | Fri Mar 21 02:45:45 EST 2003 | emeto
Hi, there is one very important thing.How many boards came out with exatly the same problem?
Electronics Forum | Fri Mar 21 21:13:03 EST 2003 | iman
Russ, u mean excess flux causes "blow hole" defect?
Electronics Forum | Thu Feb 20 11:57:48 EST 2003 | mdm4ua
I placed a micro bga using flux paste and ran it through my oven and it came out as if someone had pushed down on one side. I can find no reason for this, has anyone ever seen this and how did you fix it?
Electronics Forum | Sat Mar 22 01:05:47 EST 2003 | bcceng
I agree with Russ, seen this happen if the right amount of paste flux is not applied. You mite want to dip the spheres of the BGA to the layer of paste flux.
Electronics Forum | Fri Mar 21 08:56:29 EST 2003 | russ
Is it possible that the flux you used, if applied in excess could have caused the balls to "blow out". I have seen this in the past and it was related to the type of flux we were using and the amount. Russ
Electronics Forum | Thu Feb 20 17:18:24 EST 2003 | davef
Give us infortmation, please. What is [are]: * Height board to board side of the interposer on the low side of uBGA * Height board to board side of the interposer on the high side of uBGA * Alloy of solder balls, no paste was used correct? * Type of
Electronics Forum | Wed Dec 27 21:12:30 EST 2000 | Dave F
From a process perspective, I don�t know if you should be concerned ... You've told us nothing about your process. THE BOOK JEDEC MO-51 allows 6 thou warp in smaller [1mm pitch] BGA and 8 thou in larger [ 1.27mm and 1.5mm pitch] BGA. The increase
Electronics Forum | Mon Mar 24 08:57:20 EST 2003 | russ
I don't know if I would call it a "blow hole". what I believe happens (I don't have a camera to watch spheres during the reflow process) is that when the flux starts heating up, expansion, bubbling, or something physically displaces the balls. We fo
Electronics Forum | Wed Jan 03 12:33:37 EST 2001 | Terry Burnette
John, There is one process issue that occurs with the larger BGA packages which have coplanarity near the high end of the .2mm spec.. The defect is commonly referred to as "ball in cup" and "head in pillow". It is an open solder connection whereby th
