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Comment by ChuckMcM | Hacker News Reader

That is pretty intense. I wonder sometimes if it is a deterrent to nation states to put 'secret' back doors into silicon because a device like this would be able to prove that the device had a back door.

That said, converting a 3D image of a microprocessor level into a Minecraft world would be pretty awesome!

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Looking for backdoors could possibly turn up something interesting, but I would suspect that most backdoors if they exist are going to be in the microcode/firmware rather than the hardware. Assuming it's an encrypted blob you can't inspect outside of a running system, you'd probably have to scan both the physical layout of the chip and the electrical state, and then load both into some kind of simulator for debugging.

A standard Scanning Electron Microscope can do down to 0.1 nm, so this isn't really letting us see anything we couldn't before. SEMs are regularly used to reverse engineer chips. The main difference is that the one in the article is non-destructive, whereas with a SEM you have to strip the sample (and do imaging) layer by layer.

...and a nation state has plenty of budget to buy even multiple chips to RE destructively.

I think proving that there is a backdoor isn't a concern. A useful backdoor could probably be passed off as an engineering error. The bigger issue is that the backdoor, if exploitable by anyone, could become known.

TFA says it's only good to 14 nm but fabs are already down to 10 nm so I mean this isn't a deterrent. I don't know how STEM are for looking at chips or if we've got even more powerful microscopes but this particular one isn't good enough to stop a dedicated state level actor.

https://en.wikipedia.org/wiki/10_nanometer

I'm pretty sure you'd still be able to recognize structures/logic, even if you weren't able to exactly identify all the gory parts of a transistor.

the "14" in "14nm" does not refer to any particular dimension. Most structures in an 14nm chip are quite a bit larger than 14nm. It has been many years since the X in "Xnm" actually measured anything.

eg: https://www.extremetech.com/wp-content/uploads/2017/03/Slide...

More details exist online, for example this writeup: https://www.extremetech.com/computing/246902-intel-claims-th...

No, quite the contrary

Smaller processes are not very well refined at the moment, and anything that matters is 14nm or bigger

You're not building critical stuff on the smaller processes until they're very mature

TEM really isn't the right tool for reversing large integrated circuits. The sample prep is too finicky and involves slicing out a razor-thin sliver of material to image. You'd use it to get atomic resolution images of say a single transistor, maybe.

SEM with serial sectioning is the way to go. I'm sure people are using conventional SEMs for this already, but you could conceivably map entire circuits at high resolution (4nm) pretty quickly with one of the new multi-beam systems. Check out the SRAM cells on slide 17 o this SANDIA report (pdf warning) [0].

[0]: https://www.osti.gov/scitech/servlets/purl/1296536

(Late to the party, but:)

You may be interested in the active line of academic research into making "undetectable" hardware Trojans by subtly messing with circuits. It looks like http://asiaccs2017.com/slides/Paar.pdf (currently down, Google cache: http://webcache.googleusercontent.com/search?q=cache:kHlrZta...) is a good introduction.

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