Electronics Forum | Thu Jun 01 21:14:21 EDT 2006 | roadhound
Hello, We repair mobile (cellular) phones, and most are now having their u-BGA IC's underfilled. Can anyone suggest methods for removal of the IC's ? The manufacturers are very vague when it comes to this process, but are starting to get tired of u
Electronics Forum | Thu Mar 27 18:07:02 EDT 2014 | hegemon
If you are 100% sure that the solder has reflowed (time and temp based), then just use an wood stick to wedge the part upwards. It just takes a little bit of "lift". I used a wooden Q-Tip end that I trimmed to a wedge using an exacto blade. Wait f
Electronics Forum | Tue Jun 11 14:16:03 EDT 2013 | bandjwet
We are involved in a project for microBGA SAC rework. The pitch is 0.4mm and the devices are underfilled (softening 150C). The underfill comes off fairly easily but the pressure underneath the package as the underfill softens pushes up on the undersi
Electronics Forum | Tue Jun 11 14:21:35 EDT 2013 | bandjwet
We are involved in a project for microBGA SAC rework. The pitch is 0.4mm and the devices are underfilled (softening 150C). The underfill comes off fairly easily but the pressure underneath the package as the underfill softens pushes up on the undersi
Electronics Forum | Tue May 19 08:20:10 EDT 2009 | Mity C
Good Morning, We are underfilling some of our BGA's. This is a specified customer requirement. The material we are using is Emerson & Cuming E-1216 (also specified by the customer) The material was selected because of a close CTE match with the PCB.
Electronics Forum | Wed Dec 24 18:31:04 EST 2008 | hegemon
If they share a common ground plane you are in for some difficulty in trying to prevent the second part from heating too much. What happens to the underfill material when it is softened by being heated beyond the 160C? Does it harden up again, or b
Electronics Forum | Tue Apr 09 16:31:49 EDT 2013 | alfredodsanchez
Hello everyone! I have a problem with PCB, we detect that some contamiation apear (dark spots similar to glue or underfill) we detect that this element is Policarbonate. I don't know if on PCB fabrication process some policarbonate are used. We alr
Electronics Forum | Tue Aug 21 08:44:48 EDT 2001 | caldon
A) The standoff height of some uBGA components does not allow water to penatrate under the component. B)Water soluable may dilute the flux and not remove it all together. This can be tested with Ion Chromatography. C) Water soluable in some cases ne
Electronics Forum | Thu May 30 07:28:15 EDT 2002 | jaltland
Ben, Thanks for the input on the apertures and thickness. The side two problem, is not reflow. We have no trouble with reflow. The problem is that our product is high precision crystal oscillators. In order to get the precision needed, we have t
Electronics Forum | Wed Jan 09 01:22:39 EST 2019 | kenneth0
Hi Simond, The baking process is likely to remove any moisture after the cleaning process. We wouldn't want any moisture trapped as this might cause delamination if the package is subject to subsequent heating/reflow process. Hence there's a staging
