Hello fello technetters,  I am looking for help on a problem that we
have on polyimide multilayer boards that we build.  The issue is copper
cracking in the plated hole after 100 thermal cycles.  The lab says the
cracks are only near the prepreg and not by the core laminate in the
stackup.  I have verified all press parameters to be within tolerance.
We have seen this issue on parts that have been cured in the press and
on parts that have a post bake cure in an oven.
        Could this be a material cure issue or even a copper plating issue?

                                        Thanks!

Robert A. Stoppel
General Technology Corp.
505-345-5591  X3068

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