Subject: | |
From: | |
Date: | Tue, 09 Apr 96 13:45:50 cst |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Eddie - the problems you have brought up on the use of Palladium
finishes have been recognized by industry. We (Rockwell) have
experienced both great success and tremendous problems with Palladium
finished SOICs for both wave and reflow soldering operations. Our key
ingredient, along with other companies, is the TYPE of flux you are
using. Not all low residue or water soluble or rosin based fluxes are
the same! We tested several low residues fluxes and found that
specific fluxes did or did not perform adequately. The use of an inert
atmosphere (either nitrogen or a vapor phase environment) can give the
soldering process an extra boost too. We are reflow soldering
Palladium SOICs on military product with very low defect numbers. The
IPC 002 (component solderability), 003 (PWB solderability), and
Solderable finishes specification committees are all working on the
issue of non-tin/lead finishes. I would contact Bob Hall, Solderable
finishes task group chairman, through the IPC and see if he has any
information the committee can pass on.
Dave Hillman
Rockwell Collins
855 35th St NE
Cedar Rapids IA 52498
[log in to unmask]
______________________________ Reply Separator _________________________________
Subject: ASSY: SOIC'S IN WAVESOLDERING (fwd)
Author: [log in to unmask] at ccmgw1
Date: 4/9/96 11:42 AM
Forwarded to TechNet for Assistance
Thanks
Dave Bergman, IPC
---------- Forwarded message ----------
Date: Tue, 09 Apr 1996 13:36:48 +0100 (MET)
From: EDDIE VAN HOREN 014 57 20 08 <[log in to unmask]>
To: [log in to unmask]
Subject: SOIC'S IN WAVESOLDERING
David,
I'm looking for help somewhere in the industry on a serious soldering
problem.
Is there something like a bulletin board where items can be posted for
discussion?
Today's problem in a nutshell :
Subject : wavesoldering of SO-components (mainly SOIC).
Since a few years, Texas Instruments has changed the lead finish of the
SOIC's to a layer of nickel with a palladium flash (simplified).
This can result in 1000 ppm open solder joints when wave soldering.
In the very near future, starting next june, Motorola is also switching
to a simular leadfinish. All others are expected to follow soon.
In the farther future, useing other PCB finishes than SnPb ( NiAu,
preservated Cu etc.) will undoubtedly increase the problem.
I see this as a tremendous problem for those people who are
wavesoldering this kind of components.
Is there a way to find out whether this problem is recognized by users,
and if somebody sees a solution to the problem ?
And again, is there a way to put questions to the IPC community?
Best regards.
Eddie
Eddie Van Horen
Industrial Engineer
Alcatel Telecom Belgium
Bell Telephonelaan 2
2440 Geel
Belgium
Tel (32) 14 57 20 08
Fax (32) 3 240 48 02
E-mail : [log in to unmask]
|
|
|