Edwin,

We had a similar effort going at a previous company I worked for.
Rather than using  chemicals or sanpaper, try using a Dremel hand tool
with one of the rubber abrasive cones or wheels.  They did the trick for
us without any damage to the chip or board.  As Ralph indicated it does
thwart reverse engineering.  However, we did not go to the expense of
remarking anything.  We just removed the markings from ALL the chips.
Why keep them guessing when you can give them nothing to guess about?

Hope this helps,

Regards,

Jared Lang
Manufacturing Engineer,
Minarik Corp.
Glendale, CA.

> ----------
> From:         Edwin Maximo[SMTP:[log in to unmask]]
> Reply To:     TechNet E-Mail Forum.;Edwin Maximo
> Sent:         Wednesday, June 10, 1998 2:44 AM
> To:   [log in to unmask]
> Subject:      [TN] IC top mark
>
> We are currently using a sand paper to remove the top marking of an
> IC in our board but different problems occur such as ESD. We plan to
> use a cutting tool to scrape off the marking but it results to
> cracking of the IC. Is there any other way of removing the mark, are
> there any chemicals capable of doing it.
>
> Any information given is highly appreciated.
>
> Thanks in advance
> Edwin
>
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