Scott -

The use of dry pack is common amoung manufacturers of plastic encapsulated
microcircuits.  Take a look at J-STD-20 for further information on the
classification system.  Most component manufacturers are willing to share
information on their specific preparation and packaging techniques, and will
probably be willing to advise you in this area.

A couple of points to remember:
    1]    The vapor barrier is only as good as the packaging material and
the seal you apply to it;
    2]    Use of dry nitrogen is preferred over a vacuum.  Pulling a vacuum
on a bag can damage or deform its contents;
    3]    Desiccant is generally not desirable in these applications - it
represents a large poorly controlled lump of material, and it can behave
like a sponge under the wrong conditions.

Regards - Kelly


-----Original Message-----
From: Scott Lefebvre <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Wednesday, January 12, 2000 9:15 PM
Subject: [TN] Vacuum Sealing Components


>I wanted to know if vacuum sealing components with a desiccant bag inside
>would prevent me from having to bake my components.  I work in a relative
>low humidity environment.
>
>Scott Lefebvre
>ADC
>530-265-1041
>
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