the G-12 committee as well as the NASA whisker site simply suggests the
following:

a. there is no single event that promotes Sn whiskers
b. for every theory like this, there is enough contradicting evidence to
suggest other wise
c, it is all a matter of "reducing" the risk not eliminating it: in other
words if  you mean" controlling it" as in "minimizing risk" then u are on
the right track.


Prasad Godavarti (Dr. G)





             Guenter Grossmann
             <Guenter.Grossman
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                                                                   Subject
             01/26/2004 09:38          Re: [TN] Antw: [TN] Lead-free
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             Guenter Grossmann
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Jim

I was talking last week with a person from Motorola Germany and a
someone from Collini. In the discussion both told me that by using a Ni-
underplate and with the appropriate plating chemistry they don't' see
problems with whiskers anymore. Earlier, in a conference from
Electrosuisse, I had a discussion with a speaker talking about whisker
growth as a function of grain size of the Sn plating which can be
controlled with the appropriate chemistry and process parameters. What I
learned in these discussion was that whiskers are a problem that can be
controlled. In the worst case, in my understanding, it's a question of
money. Annealing the plating can reduce the internal stress in the
plating and diminish whisker growth.
Wrong?

Best regards

Guenter



EMPA
Swiss Federal Laboratories  for Materials Testing and Research
Centre for Reliability
Guenter Grossmann,  Senior Engineer

8600 Duebendorf
Switzerland

Phone: xx41 1 823 4279
Fax :     xx41 1 823 4054
mail:     [log in to unmask]

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