Electronics Forum | Wed Jul 09 16:05:46 EDT 2003 | davef
Sorry Matt. I mean the last row, second picture in from the left.
Electronics Forum | Wed Jul 09 04:57:11 EDT 2003 | Matt Kehoe
Our company applies solid solder to surface mount lands. While processing a micro BGA design we had some pads fall off, peel, whatever you might call it, from the surface of the board when touched "GENTLY" with the tip of a blade to remove a small s
Electronics Forum | Mon Jun 17 13:45:29 EDT 2002 | genny
When the pad comes off, is it leaving behind a "black" area? Your board may be suffering from black pad - a condition that occasionally affects ENIG finish boards. It is a process control issue with your board fabricator. The nickel is oxidising b
Electronics Forum | Thu Jun 20 03:15:22 EDT 2002 | Paul
I've seen a problem recently where there was 2 deposits of Nickle then Gold, The problem is the Nickle will not adhere to Nickle, see if you can scrape the pad away with a scalpel.
Electronics Forum | Wed Jul 09 05:28:35 EDT 2003 | matt kehoe
Photo's can be found at http://www.sipad.com/ssi_qa/smta/microbga.htm mk
Electronics Forum | Wed Jul 09 15:56:14 EDT 2003 | Matt Kehoe
Hi Dave, Hmmm, pix F2? Do you meran figure 2 or second picture? The second picture is the bare board before printing. Gold plated pads. Is that what you mean? mk
Electronics Forum | Thu Jun 20 04:49:34 EDT 2002 | scottxiao
according to the ressult of cross-section and removing the component, I find there is no black area in the left pad, and the IMC is also normal, so the black nickle is less impossible. the PCB material is not common FR4, just some thing like ceramic,
Electronics Forum | Wed Jun 12 08:13:29 EDT 2002 | davef
Don't sound proper. There is no specification. Pad peel strength test methods are: * IPC-TM-650, Method 2.4.21 for multiple solderings * IPC-TM-650, Method 2.4.8 for copper peel with a Instron machine. Typical requirement for Cu is: 6 lbf/in [1
Electronics Forum | Wed Jul 09 16:18:51 EDT 2003 | Matt Kehoe
Hi Russ, Thanks for the input. The squeeze out we are reworking is very very thin since it has been flattened so it is actually easier to remove than usual but I agree, with a pad this small it could exert a bit of stress on the bond line if rework
Electronics Forum | Thu Jul 10 09:55:47 EDT 2003 | davef
A reading of the pictures is: A1: Looks like pad [B1] is smaller than the other pads. It�s weird that the pads are such different colors. A2: Looks like pad [B1] is smaller than the other pads. Solder mask opening [B1] is misregistered and seems s
.gif)
winsouce.jpg)