Hi Don!

You're not being dense, I don't think I've explained things well
enough...this is one of those times that a picture is worth a thousand words.
I've got some drawings at work that I can scan and post on my web page...but
I'll need to get back at work to do that.

This little 2-inch-by-2-inch substrate, is an assembly in, and of, itself.
It's a double sided SMT assembly with at what I would guess close to
100-components on it. SDRAM, caps, some resistors, and SMT interconnect
devices that allow it to be plugged into a main board.

In the center of it, is a die that has been wire bonded and sealed with a
metal lid, that's the way we'll get them. We'll receive them this way, with
all this soft gold plated over everything, and then need to assemble all the
SMT components that I spoke of above, to this ceramic substrate that just has
the sealed, wire bonded die installed inside...that's what kyocera gives
us...this is a mini, double sided, pure SMT, ceramic substrated assembly for
all tends and purposes.

I just need to figure out how to get rid of all the gold on the SMT pads that
resulted from plating the whole deal so that the wire bond operation could be
performed for the die in the cavity of the substrate. It seems that the gold
that needed to plated for that process couldn't be restricted to just the
cavity where the die is, but was plated all over the whole substrate, with it
being even thicker outside the cavity outside where the die is, where the
wire bonding is being done...

I know that something like this hasn't been seen by many others, and I
understand all the questions. I just want to learn if the is a way to HASL or
wash the gold away from a 2" X  2" ceramic substrate...I'll show some
drawings of what this little beast is and then it will be easier to
understand....

-Steve Gregory-


> Steve:
>
> Excuse me for being dense.  If you're going to ;lug the carrier into a
> socket, why do you need to remove the gold.........or did I miss something.
>
> Don Vischulis
>