Darrel,
       excellent point which I have never seen raised in any technical
publication. I would think that the traditional service engineers tool of
freezer spray should be considered a method of last resort for
BGAs/uBGAs/CSP etc. since such devices are highly moisture sensitive due to
the particular nature of their construction and the common applications
(DSPs, CPUs etc) having quite a high operating temperature. If you don't
already have a potential latent defect in the device you  might well
encourage one if you hit a hot device with freezer.

The other important point is that some freezer sprays are not considered
safe on static-sensitive devices, make sure if you do use them that you use
one which does not induce static charge, eg Electrolube Minimal Charge
Freezer or Chemtronics Freez-it Antistat.


Nigel Burtt
Production Engineering Manager
Dolby Labs - European HQ
Email: [log in to unmask]
Tel: +44 (0)1793 842132
Fax:+44 (0)1793 842101

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