Is everyone baking their boards with components stuffed or are you all baking bare PCBs?  We currently bake stuffed PCAs for 6 hrs in a 150F vaccuum oven.  If it sounds like a long time, well, it probably is.  We have some experiments planned to see how long is long enough.  If anyone wants results, contact me directly.  If anyone has suggestions as to how long should be long enough, please don't hesitate to let me know [as if anyone out there would!! :-)  ] 

Eric Kalgren
BFGoodrich Aerospace
Data Systems Division
[log in to unmask] 
(505) 938-5139

>>> Werner  Engelmaier <[log in to unmask]> 10/14/99 07:57AM >>>
Hi Steve,
Your root cause for the delaminations is moisture absorption, that is why
baking works. Boards subjected to high air humidity for a sufficient time
will fully saturate (at local ambient equilibrium). The time necessary will
primarily depend on the polymer involved and on the location of the P/G
planes.

Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL  32174  USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask], Website: www.engelmaier.com 

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