Hi Steve! Well, you either have a case of poor cleaning which has left flux
residues/assembly residues on the components, a case of electrochemical
migration of the component termination due to ionic residues, or the
combination of both! What type of flux was being used during assembly?
(Very cool crystalline structure in the high mag photo!).

Dave Hillman
Rockwell Collins
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                      Steve Gregory
                      <[log in to unmask]        To:       [log in to unmask]
                      M>                       cc:
                      Sent by: TechNet         Subject:  [TN] Crystalline growth across a capacitor...
                      <[log in to unmask]>


                      05/03/2004 11:13
                      AM
                      Please respond to
                      "TechNet E-Mail
                      Forum."; Please
                      respond to
                      SteveZeva







Mornin' All!

Had some pictures sent to me asking if I've ever seen this phenomena
before,
and did I know what it might be. Go to:

http://www.stevezeva.homestead.com and look at "Growth @ 20X, 32X, and
1900X"

Kind of crystalline looking at the higher magnification. He say it's tin
based stuff.
Tin Carboxylates maybe?

-Steve Gregory-

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