That what I always wonder. There's gotta be a limit in there somewhere... right? Maybe? But they just keep finding new ways to make 'em even smaller yet. How far will we go, and what will our devices and industry look like by the time we can't go any further?
It's quite possible we're at the cusp of the plateau already. For many years planes kept getting faster and faster, until one day they didn't. It may be the same with processors. For years they'll keep getting smaller and smaller, until one day they don't. In fact, this already happened with clock speed 10 years ago. The top Pentium 4s, while certainly worse than the Haswell i7s of today, have about the same clock speed (3.8 GHz or so).
That's due to thermal and electrical limits of Silicon and whatever you are using to insulate (Silicon Dioxide)... having a semiconductor with a higher bandgap (Such as many III-V semiconductors, such as indium gallium arsenide), you can have a much higher clockspeed.
I'm really interested in this, could you please explain more? My impression is that the heat from subthreshold current is what's limiting today's CPUs. How does a higher bandgap help you achieve a higher clockspeed for the same power density?
I don't know if you'd count these one-off experiments in the same league as making aircraft that you can actually turn a profit manufacturing and operating. That game seems to have dried up at about the size and speed of modern jetliners, given the issues we've had with operating supersonic commercial aircraft.
I'm sure somebody in a lab somewhere can make a single processor that's ridiculously fast compared to anything you can buy, but being able to manufacture usable, reliable CPUs in quantity and cheap enough to turn a profit on selling them is a whole 'nother ballgame.
I don't think that there is a way to go smaller than an atom. Most likely, there will be a sifht in technique. My guess is quantum computing, but who knows.
