From: tcmay@got.net (Timothy C. May)
Date: Mon, 1 Apr 1996 19:48:38 +0800
To: perry@piermont.com
Subject: Re: [NOISE] Cable-TV-Piracy-Punks
Message-ID: <ad847d2604021004131b@[205.199.118.202]>
MIME-Version: 1.0
Content-Type: text/plain


At 7:36 PM 3/31/96, Mike Duvos wrote:

>We aren't talking about IC masks here.  We are talking about
>electrostatic charges which would instantly leak away if the
>insulation around them were in the least bit compromised.

The surface layers above the active portion of a chip can be stripped away
and chip remains functional. This includes the outer packaging layers
(epoxy, or of course, ceramic with metal lids) and parts of the so-called
"scratch protection," usually a type of silicate glass.

The active capacitors are not affected by removal of these layers.

>Such data wouldn't even survive the preparation for scanning
>microscopy, much less the actual inspection process.

Actually, we did it all the time in my lab at Intel, and I understand from
my former co-workers that the technology has only gotten better. (This does
not mean voltage contrast is easy. For one thing, modern chips have 3-5
metal layers, due to spectacular advances in chem-mechanical polishing, and
each metal layer acts as a ground plane shielding the lower layers from
visibility and inspection with electron beams. And EPROM and EEPROM cells
are effectively impossible to analyze, for various reasons.)

This does not mean I think reverse-engineering of smart cards or satellite
boxes is easy.

SQUIDs won't do it, either.

--Tim May

Boycott "Big Brother Inside" software!
We got computers, we're tapping phone lines, we know that that ain't allowed.
---------:---------:---------:---------:---------:---------:---------:----
Timothy C. May              | Crypto Anarchy: encryption, digital money,
tcmay@got.net  408-728-0152 | anonymous networks, digital pseudonyms, zero
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