Reference "The Boy who cried Wolf". That pronouncement has been made and proven wrong way too many times for anybody to take it seriously. Eventually the wolf will come and the limit will be reached, but until it happens nobody will believe it.
I agree with those who say we'll reach a cost barrier before we reach a technical barrier. If I were to make a wild guess, I'd say 7nm will be that limit, and that it'll be about 5 years away (Moore's Law is already broken and isn't likely to be fixed any time soon, hence the slower timeframe).
There's no way silicon microlitography will keep working once transistors are just a few atoms big. In fact, at 10 nm tunnel currents should be already a big problem on all sides of the transistors, and not constrained to the gate - channel insulation anymore.
That's why I mentioned molecular assembly.
>"In fact, at 10 nm tunnel currents should be already a big problem on all sides of the transistors, and not constrained to the gate - channel insulation anymore."
That's why I mentioned silicon photonics.
> "A cost barrier is the most common manifestation of a technical barrier."
It can be, but not always. We can definitely move beyond 7nm, we've already done it in the lab, but knowing if we can find ways to afford the costs of manufacturing below that point is not as clear.
http://www.purdue.edu/newsroom/research/2012/120219KlimeckAt...
That's the question to answer. It's just as hard to prove that you CAN'T assemble a transistor of that size.