Yeah Les,

I agree about polyimide as a poor bond resin system. It doesn't like itself much and that brings to
mind some old experiments trying to foil laminate with it. That was interesting.

I also agree about epoxy's inherently better bond. It's just that I can't remember all that other
stuff as I used to classify the TCE (as it was termed in my early days and I won't let go) of Cu as
being 19 ppm/C. and Al being 22. See how I can cheat. Because I can't remember, I called it relative
- to that of ceramic (as an example) being 5-7 and most laminates (X-Y) being around 12-15?.

About Invar - I used to use a 20% HCL solution, after drill/etchback, and immediately before plating
processes to ensure acceptable plating (there was no oxidation with magical timing). You know, it
almost sounds like CIC is going to make a comeback. Is this a good thing? Maybe your idea about Cu
is best for most "normal" applications.

In any case, I wonder what was the original question? Would someone please inform us all as to the
final decision and how well it works. We offered advice. Now who will apply it all - as if it all
hasn't been done so many times before - it's still interesting.

Let's all get stiff,

Earl Moon

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