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Are processors pushing up against the limits of physics?

arstechnica.com

1–10 of 47 posts

Re: Are processors pushing up against the limits of physics?

#3
Right now, the laws of economics are a bigger problem than the laws of physics. Field effect transistors have been shown to work 5nm and even 3nm. However, the new lithography technologies needed to reach those resolutions cheaply are nowhere near ready.

Re: Are processors pushing up against the limits of physics?

#4
A metric that really puts things in perspective is the following: take a common consumer CPU, clocked at 3.4Ghz. That means it executes 3,400,000,000 cycles per second. Divide the speed of light by this number, and you obtain approximatively 0,088m.

During the time your standard desktop CPU takes to finish a cycle, light only travels 9 centimeters.

Re: Are processors pushing up against the limits of physics?

#5

Right now, the laws of economics are a bigger problem than the laws of physics. Field effect transistors have been shown to work 5nm and even 3nm. However, the new lithography technologies needed to reach those resolutions cheaply are nowhere near ready.

I heard a rule of thumb that fab costs go up about 40% with each reduction in size. Is that accurate?

Re: Are processors pushing up against the limits of physics?

#6

Right now, the laws of economics are a bigger problem than the laws of physics. Field effect transistors have been shown to work 5nm and even 3nm. However, the new lithography technologies needed to reach those resolutions cheaply are nowhere near ready.

I heard a rule of thumb that fab costs go up about 40% with each reduction in size. Is that accurate?

Intel paid ASML ~$4.1 billion to deliver 10nm lithography. That was ~ 1.5yrs ago (http://www.intc.com/releasedetail.cfm?ReleaseID=690165). ASML stock is a good indicator what's happening in this business.

Intel has running 14nm which is 16% better on SRAM cell than 16nm TSMC.

Re: Are processors pushing up against the limits of physics?

#7
post #4

A metric that really puts things in perspective is the following: take a common consumer CPU, clocked at 3.4Ghz. That means it executes 3,400,000,000 cycles per second. Divide the speed of light by this number, and you obtain approximatively 0,088m. During the time your standard desktop CPU takes to finish a cycle, light only travels 9 centimeters.

Just a side not that light in other medium than air travels slower. It's not 300k km/h but ~200k km/h in FR4 microstrip (6"/ns where 1ns is equivalent to 1GHz clock).

Re: Are processors pushing up against the limits of physics?

#8
No. Every single time someone supposes that any piece of technology is approaching its limits, the answer is no. Technology will continue to improve and advance as we make new discoveries. The simple fact is we do not know the future, so pretending like we know what things will be like in 20 or 50 years is just pointless. What's with this obsession of taking today's technological knowledge and assuming that things won't drastically change? Nobody should ever pretend to know what the future holds.

Re: Are processors pushing up against the limits of physics?

#9
They say we can't get smaller than an atom, but electrons are smaller than an atom, and we don't even have to use just the charge but can also use properties like spin and momentum to get more values out of them. I.e. spintronics. Then of course there are photons as well. The article mentions itself that we use light for etching features even less than the wavelength of the light nowadays. Sometimes you need a big read-write head or something, but then you can just push magnetic domains past it on a wire, etc. so that isn't necessarily the size of piece of computation in the device if we move beyond transistors.

Re: Are processors pushing up against the limits of physics?

#10
post #8

No. Every single time someone supposes that any piece of technology is approaching its limits, the answer is no. Technology will continue to improve and advance as we make new discoveries. The simple fact is we do not know the future, so pretending like we know what things will be like in 20 or 50 years is just pointless. What's with this obsession of taking today's technological knowledge and assuming that things wo…

Things will drastically change. But given piece of technology has its limits. Assuming it does not is like expecting horses to run faster than sound some time ago.
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