Allen

No wonder that no maximum thickness is defined, since Werner states that
the solder joints are more reliable the thicker the solder between pad and
pin is. I can't fully agree with this statement however. We saw in various
experiments that shear bands at the interfaces ( Tin/pad; Tin /lead) occur
that are approx. 15um wide on either side. This results in a maximum
thickness for reliability predictions of 30um ( I'm sure Werner and I could
have endless discussions about this ) . But also this does not imply a
maximum allowances for the solder thickness.

Best regards

Guenter

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