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When setting a story in the future I always try to limit the technology available. It's less enjoyable and harder to identify yourself with droney the drone than with John and Jane Doe.

Currently I use a mechanic that's unimportant fluff. The mechanic causes electric signals in small wiring and components to become unpredictable, so components have to be larger than that to function. The problem is that human nerves also use electricity, and a single nerve axon can be as small as 0,2 micrometer. So I would like to know: If I limit electrical component sizes to 0,2 micrometer, how much computational power would I have and what time period did humans pass this computational power?

Looking around I found these pictures that seem to contradict each other about when certain feature sizes on chips were passed:

picture 1

picture 2

picture 3

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closed as off-topic by Liam Morris - Reinstate Monica, We are Monica., Nosajimiki, L.Dutch - Reinstate Monica May 5 at 18:40

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about worldbuilding, within the scope defined in the help center." – Liam Morris - Reinstate Monica, We are Monica., Nosajimiki, L.Dutch - Reinstate Monica
If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Why do they contradict each other? All of them put the 1 micron around the 1990 $\endgroup$ – L.Dutch - Reinstate Monica May 5 at 9:12
  • $\begingroup$ @L.Dutch the 100nm range is around 2008 in the first picture, 2004 in the second picture and 2002 in the last picture. 10 Nm is estimated around 2025 in the first picture, 2015 in the second picture and ~2018 in the 3rd picture. This is too much differences between the pictures for me to say "yep, this is correct", even though they might overlap fairly close at the 1 micron range. $\endgroup$ – Demigan May 5 at 9:36
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    $\begingroup$ In human nerves the electrical manifestations are unintended side effects; the nervous signal is transmitted chemically. The chemistry in question involves moving sodium and potassium ions across a membrane, and since those are ions (electrically charged atoms) this gives rise to a directly mesurable variation of electrical charge. Nervous signals propagate at chemical speeds (tens of meters per second), very much unlike the speed of light at which electrical signals propagate. Note that in real life the mechanism of your world is quite real, but it kicks in at much smaller sizes... $\endgroup$ – AlexP May 5 at 9:38
  • $\begingroup$ The first Intel Pentium processor with 0.25 µm features (Tillamook) was introduced in 1997. $\endgroup$ – AlexP May 5 at 9:40
  • $\begingroup$ @AlexP I've always found nerves to be complicated. Are you sure nerves are 100% chemical? I thought they were chemical in the synapses and a combination of chemical (salt-pump) and electrical in the axons themselves. Otherwise, how could a myelin sheath accelerate an action potential across an axon? en.m.wikipedia.org/wiki/Myelin. en.m.wikipedia.org/wiki/Saltatory_conduction $\endgroup$ – Demigan May 5 at 12:24
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As an Electrical Engineer I was designing sub-1u in the 1990s

And it was a big deal because there were scientists who thought breaking the 1u barrier couldn't be done. Then there were scientists who thought that breaking the 0.1u barrier couldn't be done (until it was in the early 2000s).

The problem is that molecular sizes are measured in angstroms, or 10-10. There comes a point where the polysilicon gate simply can't be made physically wide enough to carry enough electrical charge to manipulate the gate. One would logically think that this occurs at 3 molecules in thickness.

But, so far that limitation has not revealed itself!

Why are the graphs so imprecise?

Because applications vary all over the place. Logic led the way with sub-micron designs very early on because they needed vanishingly low power. Remember what I said about "not enough electrical charge?" Well... if you don't need a lot of electrical charge in the first place... Saving the planet was only one of the reasons driving low-power designs.

At the same time, you still had applications ranging from audio to bus drivers that had to push a boatload of energy somewhere. Those designs were still being build with 5-10u scale transistors. In my world, we dealt with BiCMOS (bipolar and CMOS tech on the same wafer). We commonly mixed sub-micron CMOS with super-micron bipolar.

Even in the future, there will always be reasons to build bigger-than-nanometer gates. But that won't stop us from building nanometer gates.

But the simple answer is: the graphs reflect when the technology was commonly used, not when it was first used or initially available. In short, the graphs are conservative.

OK, so what date should I use?

I'm a fan of 2000. It's a nice, round number and reflects some of the earliest uses of 0.2u and less designs.

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It depends... and this is why:

The economics of equipping a factory.

Essentially the broad strokes of Moore's law are a straight line, when time is plotted against a logarithmic size metric.

Production technology on the factory floor doesn't change in this way. Significant investment in new technology necessary in production must stick around long enough to pay for themselves or be changed in response to a significant change in marketing and investment strategy - so even when the research has leapt ahead, there will be a significant delay before production techniques catch up, then a sudden leap forward.

The 350nm lithographic chip manufacture was introduced in 1995, updated to 220nm in 1999 by both IBM and Motorola, 180nm processes were brought in variously:

  • Intel 1999

  • Fujitsu 2000

  • IBM 1998

  • Samsung 2001.

You may notice that for IBM the manufacture of 180nm occurred before 220nm and continued concurrently for some time:

A prime example would be the rather successful NMOS 68000 by Motorola (1979), designed by hand - ie not using a complex CAD package, only finally ceased production in 2000. In concurrent production for most of it's life with the more advanced CMoS version.

So the answer depends on "which company?".

  • As to the pictures, I'm only able to find a source for one of them, and no indication as to where the data points are derived from - without more information all I can say is, they're using different data.
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