Subject: | |
From: | |
Date: | Fri, 30 May 97 06:21:17 cst |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Zoran -
Many of the users in the ANSIJ-STD-003 PWB solderability committee who
have experience with immersion Au/Ni finishes have reported that a
"good" immersion Au/Ni finish should last 12 months under typical
storage conditions. The critical part of the equation seems to be
finding a finish supplier understands their immersion gold chemistry
and that does a good job of process control. Also take a look at "Fine
Pitch Surface Mount Technology Assembly with Pb free low Residue
Solder Paste", I. Artaki, Soldering and Surface Mount Technology, May
1995, page 27 - it may be helpful. Good Luck.
Dave Hillman
Rockwell Collins
[log in to unmask]
______________________________ Reply Separator _________________________________
Subject: ASSY:Au/Ni Coated Boards
Author: [log in to unmask] at ccmgw1
Date: 5/28/97 9:08 PM
Dear Technetters
We have some printed circuit boards with gold over nickel coating which
are experiencing solderability problems, ie very poor wetting. I have
heard that this may be due to nickel migration through the gold over
time. The boards are approximately 6 Months old. Is there a particular
shelf life for this type of coating before we need to dump the boards?.
Regards
Zoran Raich
Process Engineer
NetComm (Aus) Ltd
(+612) 9878 7394
[log in to unmask]
***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]> *
* with <subject: subscribe/unsubscribe> and no text in the body. *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] *
***************************************************************************
***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]> *
* with <subject: subscribe/unsubscribe> and no text in the body. *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] *
***************************************************************************
|
|
|