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Security firm needs a very easily broken conductive sheet

2003

Hi,

First the application:
I am working on a security electronics PCB. Its primary goal is to be used by all the security maniacs that communicates with personal computers thru the internet. Basically for two people to communicate they must both have this SECURE PCB connected to (probably) USB. Then thru an API, messages can be sent for encryption/decryption to it.

Now the problem:
This PCB must be secured against penetration attacks.

The solution (well more like dream)
Use some type of envelope with very thin conductive tracks. This envelope will cover the entire PCB and then some EPOXY will be potted in. If one of the tracks is broken the power to the memory device within the PCB will be removed. This envelope must have the conductive tracks made of very thin and easily broken material! In fact it would be nice to be broken by un-careful handling; and of course it must be broken if someone tries to remove the epoxy by using some tool or even by etching!

BIG PROBLEM and my question
Where is this wonderful material!? Does anyone here knows of some conductive material that I can use for this?

Thanks and regards,

Alfonso Sousa Julinho
electronic engineer - Lisboa, Portugal

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It is relatively easy to deposit a conductive path on an envelope many different ways, using conductive paint, two-part silvering, electroless plating solutions, sputtering, and more. But I believe you need to think through the concept a bit more before you are ready to have conductive paths put on the envelopes, as it seems like it would take little effort for someone to poke probes through the envelope to maintain conductivity between point A and B and thin rip open the envelope.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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2004

Hi,

Your questions sounds wonderful though hard feedbacks you get from it. I'm looking into the same idea and now is in the middle of doing my research on this topic... . My research would hopefully bring some good to mankind. You could read on INK JET printing technology on PCB printing. They are doing this research for the last 18 months and still on going. Just imagine the world with it. You'll get anything as thin as a paper , and even print your circuit on paper! Where you don't need a PCB but the casing will become the PCB! Well I'm still studying and hope you could e-mail me if you read anything useful to it.

Ciao

MS Yusof
- Swansea, UK

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Hi again ....

Guess what, you might find this handy for your idea.

Look up "conductive silver pen" on a search engine.

Good luck

SALAM

MS Yusof
- Swansea, UK
2004