Can someone explain nanometers to me?

OK, I understand what a nanometer is, but not how it related to CPU/GPU design. For instance, IvyBridge is stated to use a 22nm process. OK, that means what, exactly? Are the "wires" on the silicon 22nm wide? Is the total transistor length/width/area within 22nm?

I noticed that the distance between the single atom and each of the gates in the single atom transistor article is 54nm. source This is touted to be the smallest transistor ever made. How can that be if the distance between the gates is 108nm? Didn't we drop below 100nm nearly a decade ago?

I am clearly missing something...

its metric measurement equal to one billionth of a metre, it measures the size of the transistors.

smaller is better because they use less power, there for less heat and you can fit more of them on the same sized DIE giving you better performance.

Having said that a chip with smaller transistors / more of them on a DIE does not automatically mean its a faster chip as there are a whole bunch of other things that make a CPU work.

FX-8 vs 2700K is a clasic example, both are 32nm yet the 2700K is faster because it has a more efficient HT link, add to that BD's 8 cores are bottlenecked by sharing only 4 L2 links...... if you were to put 8 module on the DIE for its 8 cores they probably would not fit. they might if it moves to 28nm or 20nm at TSMC.

Frakk said:

it measures the size of the transistors.

Click to expand...

OK, but transistors are not perfect squares/circles and they are made of multiple "pieces". How does nanometers relate to the actual dimensions of the part?

Again, I *DO* understand what a nanometer is and I understand how and why smaller is better. It is just that there is no context when we talk about the next xx-nm process. If I said my house measured 10 meters, I would expect further questions. There isn't enough information in the statement to inform anyone.

Ah right, sorry my bad... transistors react in relation to pass through current density, so the transistors are measured width / height ways.

The nanometer notation of process technology is not the size of the transistor. It is the average half-pitch, or half the distance from one transistor to the next, as measured in a DRAM IC built on that process.

The actual components that make up the transistor are much smaller.

ViperX800 said:

The nanometer notation of process technology is not the size of the transistor. It is the average half-pitch, or half the distance from one transistor to another, as measured in a DRAM IC built on that process.

The actual components that make up the transistor are much smaller.

Click to expand...

THAT is the info I was looking for! Thank you!

ViperX800 said:

The nanometer notation of process technology is not the size of the transistor. It is the average half-pitch, or half the distance from one transistor to the next, as measured in a DRAM IC built on that process.

The actual components that make up the transistor are much smaller.

Click to expand...