Ed Cosper wrote:
>
> Hi all,
>
> Many shops have installed and are running Electrochemicals shadow process.
> We have been running it over 6 years now. However, as hole sized get smaller
> we are seeing more voids than usual. The actual cause of the voids is
> somewhat of a debate at this time. The effect of not having a fixer module
> on our shadow line seems to be primary focus at this time. Perhaps those of
> you who are using shadow and are drilling .0135 holes would care to share
> your experience along these lines. What is your opinion on a fixer module.
> Is it necessary?  If we install one, do you think it will help reducing
> voids in small holes.
>
> The supplier highly recommends it but I never loose sight of the fact that
> they are in business to sell equipment. So, without any intention of
> slighting our suppliers suggestions ( who I find the majority of the time
> correct is their recommendations) , I always inquire with folks actually
> using the products before I decide to endorse spending any money that may
> not be necessary.
>
> All comments are appreciated.
>
> Ed Cosper
> ##############################################################
Go for the fixer it will prevent excessive Shadow in the holes and on
inner layer copper.
As for voids this can be caused if the whole board including holes are
not bone dry before
the micro etch. The smaller the hole the more difficult to dry it.

We have been plating 16:1 aspect ratio holes in boards up to 0.25" using
Shadow since 1995
and do not get voids.

I hope my comments may help as it is nice to think that I am now able to
give something in
return for seeing you Shadow line in 1994.

Regards

Roger Hammond

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