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Moores law stated transistor density per square inch roughly doubled every 2 years. I see no end in sight for that specific law. As we can always go vertically

• karmasimida 3y ago
  Smaller transistor means lower energy consumption, going vertical won’t solve this. This ceiling will be hit much earlier than what process/technique allowed.
  • bigmattystyles 3y ago
    smaller energy per transistor, but if you're packing more in the package, the package's consumption will grow up. Also, I think leakage current (and the heat that comes with it) goes up the smaller the feature size.
• valianteffort 3y ago
  Not to be pedantic but wouldn't stacking transistors have no effect on density per square inch? Since it would only increase density per cubic inch.
  • bushbaba 3y ago
    I view it as if you cut 1 square inch of a motherboard. That the every 2 years you’d expect to see roughly double the number of transistors in that cut out piece. Scaling vertically would “technically” still meet the above.
    • fnordpiglet 3y ago
      I don’t think that’s what they mean by per square inch. They mean in a plane, not a volume. If you add a third dimension the law stays the same, because a volume is two planes and the density law applies to each independently. That’s why node sizes are a single value not a two dimensional value. A 3nm node is 3nm feature sizes, regardless of dimensionality.
      • bee_rider 3y ago
        The quote given on Wikipedia is: > The complexity for minimum component costs has increased at a rate of roughly a factor of two per year. Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years. If he was talking about the area of a single transistor, there would be more concise ways to put it.
    • quickthrower2 3y ago
      Even a 1000ft thick motherboard?
      • qup 3y ago
        That'll show Moore
        • quickthrower2 3y ago
          More’s law: if there is more of it, it does more!
  • reaperman 3y ago
    Stacking transistors increases density per square inch if it can be done on a single wafer of silicon, because its "per square inch of fab wafer silicon"
  • bee_rider 3y ago
    We include multi-story buildings when we calculate population density, why not include multi-story chips?
• bigmattystyles 3y ago
  To be fair, if you stack them, density is not going up - only if ignore the number of stacks and take one of their areas for the total number of stacked transistors would it then go up. Plus, stacking is great, but with heat issues, isn't the industry going to many dielets with a massive interconnect?
  • reaperman 3y ago
    Heat issues are very valid. But the "per square inch" density is relative to a square inch of fab wafer. So if it can be done on one wafer, it counts. If it's stacking discrete chipsets, not so much.
    • cubefox 3y ago
      Stacking likely wouldn't save substantial cost compared to producing multiple different wafers. It could even increase cost if it decreases yield. That's very different from making the transistors smaller, where the cost per transistor decreased exponentially in the past. People focus too much in Moore's law (transistors per area), when the only interesting quantities are 1) price per performance and 2) power draw per performance.
  • grogenaut 3y ago
    If measured in square inch the 3rd and more importantly the 4th dimension are not accounted for and are basically free. Another way to say it is to count the famous founder brown: ymmoore wasn't thinking 4th dimensionally. For shame really
• rudedogg 3y ago
  > I see no end in sight for that specific law. As we can always go vertically if needed. Not a hardware person but heat dissipation becomes more of a problem when you go vertical IIRC.
• lmpdev 3y ago
  > As we can always go vertically if needed. I don't think you understand how difficult non-planar transistors are to engineer at scale
  • CyberDildonics 3y ago
    How difficult is it? Difficult or really really difficult?
• zamadatix 3y ago
  Per your link, Moore's law also doesn't state anything about density. Density is just one of the ways "The complexity for minimum component costs has increased at a rate of roughly a factor of two per year.", i.e. Moore's law only ever stated transistor count per a given price roughly doubled every 2 years.
  • reaperman 3y ago
    Moore's original article on the topic in 1965[0], and the same with additional context interview form 2005[1]. > "The original Moore’s Law came out of an article I published in 1965...I had no idea this was going to be an accurate prediction, but amazingly enough instead of ten doubling, we got 9 over the 10 years, but still followed pretty well along the curve. And one of my friends, Dr. Carver Mead, a Professor at Cal Tech, dubbed this Moore’s Law. So the original one was doubling every year in complexity now in 1975, I had to go back and revisit this... and I noticed we were losing one of the key factors that let us make this remarkable rate of progress... and it was one that was contributing about half of the advances were making. So then I changed it to looking forward, we’d only be doubling every couple of years, and that was really the two predictions I made. Now the one that gets quoted is doubling every 18 months...I think it was Dave House, who used to work here at Intel, did that, he decided that the complexity was doubling every two years and the transistors were getting faster, that computer performance was going to double every 18 months... but that’s what got on Intel’s Website... and everything else. I never said 18 months that’s the way it often gets quoted." Anyways, See slide 13 here[2] (2021). "Pop-culture" Moore's law stated that the number of transistors per area will double every n months. That's still happening. Besides, neither Moore's law nor Dennard scaling are even the most critical scaling law to be concerned about... ...that's probably Koomey's law[3][5], which looks well on track to hold for the rest of our careers. But eventually as computing approaches the Landauer limit[4] it must asymptotically level off as well. Probably starting around year 2050. Then we'll need to actually start "doing more with less" and minimizing the number of computations done for specific tasks. That will begin a very very productive time for custom silicon that is very task-specialized and low-level algorithmic optimization. [2] Shows that Moore's law (green line) is expected to start leveling off soon, but it has not yet slowed down. It also shows Koomey's law (orange line) holding indefinitely. Fun fact, if Koomey's law holds, we'll have exaflop power in <20W in about 20 years. Which should be enough for people to create ChatGPT-4 in their pocket. 0: https://www.rfcafe.com/references/electronics-mag/gordon-moores-law-electronics-mag-april-19-1965.htm https://www.rfcafe.com/references/electronics-mag/gordon-moo... 1: https://cdn3.weka-fachmedien.de/media_uploads/documents/1429521922-13-gordonmoore1965article.pdf https://cdn3.weka-fachmedien.de/media_uploads/documents/1429... 2: (Slide 13) https://www.sec.gov/Archives/edgar/data/937966/000119312521287742/d133133dex993.htm https://www.sec.gov/Archives/edgar/data/937966/0001193125212... 3: "The constant rate of doubling of the number of computations per joule of energy dissipated" https://en.wikipedia.org/wiki/Koomey%27s_law https://en.wikipedia.org/wiki/Koomey%27s_law 4: "The thermodynamic limit for the minimum amount of energy theoretically necessary to perform an irreversible single-bit operation." https://en.wikipedia.org/wiki/Landauer%27s_principle https://en.wikipedia.org/wiki/Landauer%27s_principle 5: https://www.koomey.com/post/14466436072 https://www.koomey.com/post/14466436072 6: https://www.koomey.com/post/153838038643 https://www.koomey.com/post/153838038643
• audunw 3y ago
  An implicit aspect of Moores law has been that cost per transistor has been going down as the density is increasing. This doesn't seem to be the case anymore. The technology required to get higher transistor density is getting ridiculously expensive. We're not seeing the power benefit of scaling down transistors either, since leakage is starting to get too high. I guess there's one more trick in the pipeline with Gate-All-Around, but I don't think I see a path to get better gate control after that. And if we don't get power consumption per transistor down, then stacking transistors in layers to increase density isn't going to be very viable for compute chips, since you need to get the heat out of the chip. IIRC, Intel is working on putting the power metal layers on the back side of the chip, which grows the chip vertical in the other direction so to speak. And it helps wick away heat as well, so could open a path for a few layers of compute transistors. But all this adds a huge amount of complexity to manufacturing, so at some point it might not be worth the cost anymore.
  • cubefox 3y ago
    I thought the power benefits of shrinking still hold up rather well, in contrast to cost. E.g. new Nvidia gaming cards have smaller GPUs for the same price as the respective old generation, meaning the cost per chip area doesn't stay constant for improved manufacturing nodes. So the price per transistor shrinks slower than the number of transistors per chip area grows. At some point in the future the price per transistor would go up rather than decrease. Then the value of shrinking structures could stem, at best, from lower power draw per transistor. For mobile devices. But even power draw per transistor may stop decreasing at some point. Then further shrinking the process nodes would be useless.
• Symmetry 3y ago
  That's a common misconception and I'm not surprised it made it into Wikipedia. Moore's 1965 paper was the first time anybody had pointed out the exponential nature of progress in miniaturizing transistors and packing more of them on the same integrated circuit. But it wasn't until 1975 a the same conference where Dennard presented his scaling laws that the phrase "Moore's Law" was coined in an interview where someone was trying to explain Dennard scaling to a reporter. The original coining was ambiguous as to whether it meant more transistors, faster transistors, or smaller transistors and that ambiguity remained in its usage because from 1975 until about 2005 they all went together just as Dennard said they would. And my lecture notes from a class I took on semiconductor physics in college had a photo copy of a memo from Moore himself endorsing this broader conception of Moore's Law.