Hi Russ! I am reporting on a DOE study that investigated the interactions of
immersion tin, immersion silver, HASL,  BGAs and conformal coating (yes it was a
lot of work but it was very enlightening) at the APEX conference in March. The
presentation is Tuesday AM, March 14 and the paper itself will be in the
conference proceedings. The conclusions: the immersion finishes were comparable
to the HASL finish and conformal coating neither degraded or enhanced the
thermal cycle fatigue life of the BGA solder joints. The immersion finishes are
going to have a significant impact on SMT assembly in terms of coplanarity,
board cost, and process options. Good Luck.

Dave Hillman
Rockwell Collins
[log in to unmask]





Russell S Gregory <[log in to unmask]> on 02/25/2000 01:12:24 PM

Please respond to "TechNet E-Mail Forum." <[log in to unmask]>; Please respond to
      [log in to unmask]

To:   [log in to unmask]
cc:

Subject:  [TN] Immersion Tin



Dear All,

I am interested in the benefits of Immersion Tin as a final finish.
Do any of u use Immersion Tin as a final finish?
Why do u use it and what did u change from?

What are the benefits for you of an Immersion Tin?

What are the drawbacks?

Does an  Immersion Tin have to pass a specific test for approval?
Do all Immersion Tins give u the same benefits?

Russ Gregory

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################