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Moore's Law Fails At NAND Flash Node

Posted by Unknown on from the honey-i-couldn't-shrink-the-transistor dept.

An anonymous reader writes "SanDisk sampling its 1Y-based NAND flash memory products and has revealed they are manufactured at same minimum geometry as the 1X generation: 19 nm. The author speculates that this is one of the first instances of a Moore's Law 'fail' since the self-fulfilling prophecy was made in 1965 — but that it won't be the last."

27 of 147 comments (clear)

  1. Shortage, no. by Impy+the+Impiuos+Imp · · Score: 5, Interesting

    There's a granularity to advancement as it is made of discrete units of advancement and invention.

    Also, I wouldn't pooh pooh the use of other techniques to keep things moving. In the terms economists use to analyze advancement, this is called "substitution", and is the source of the counter-intuitive but powerfully predictive observation that, in a free economy, people can invent ahead of the curve faster than things become problems, like shortages.

    --
    (-1: Post disagrees with my already-settled worldview) is not a valid mod option.
    1. Re:Shortage, no. by mc6809e · · Score: 2

      It's a pity there are no free economises then.

      They never were free.

      People just didn't realize how much they were under the control of the state.

      This is why many immigrants are successful business people -- they haven't been here long enough to know the extent to which the state can step in and take control.

      The rest of us have the sense not to make a move for fear of doing something wrong. There are so many laws that it would take a life time to comprehend them and whether or not a decision meets the state's approval.

      That or one hires many lawyers.

    2. Re:Shortage, no. by ShanghaiBill · · Score: 2

      Didn't Moore's Law include a ten year limit anyway?

      Moore's law was really just an observation made in a 1965 edition of Electronics Magazine. The term "Moore's Law" wasn't coined until 5 years later, when, in hindsight, his prediction proved correct. Over time, many, many people have tried to predict when the trend would stop. So far they have all been wrong. But with what we know about semiconductor physics, it is hard to see the trend continuing much beyond 2020. But that doesn't mean computers will stop growing more powerful. If we can figure out how to cool them, we can stack up silicon layers in 3D structures. Or switch to molecular circuits. Or something else.

      There are some other related "laws":

      Moore's corollary: The number of transistors double every 24 months, but as the transistors get smaller, they also get faster, so the performance doubles every 18 months.
      Rock's Law: The cost of a semiconductor fab doubles every four years.
      Kryder's Law: The storage density of disk drives doubles every year (this has held true for much less time than Moore's Law).

  2. It has not failed yet by Anonymous Coward · · Score: 5, Informative

    Moore's Law applies to the number of transistors in a chip. Just because you have found an increase in performance that did follow Moore's Law for a while does not mean that Moore's Law is somehow about flash memory. Therefore, when the increase no longer follows Moore's Law, it does NOT mean that Moore's Law has failed. The only thing that has failed is your own prediction that things other than the number of transistors would follow that curve.

    1. Re:It has not failed yet by wagnerrp · · Score: 2

      Moore's Law applies to the number of transistors in a chip. Just because you have found an increase in performance that did follow Moore's Law for a while does not mean that Moore's Law is somehow about flash memory.

      If Moore's Law is about transistors on a chip, and NAND flash is a bunch of floating gate transistors on a chip, wouldn't logic follow that Moore's Law applied to NAND flash as well?

    2. Re:It has not failed yet by K.+S.+Kyosuke · · Score: 5, Interesting

      If Moore's Law is about transistors on a chip, and NAND flash is a bunch of floating gate transistors on a chip, wouldn't logic follow that Moore's Law applied to NAND flash as well?

      Sort of. First, they're more like "capacistors" than transistors - their size may have some implications for them that it doesn't have for normal transistors, especially now that they're essentially using multi-valued logic for the charges in those gates. Second, most logic circuits get exercised quite a lot of the time, and heat dissipation is often the limiting factor, but this isn't the case for SRAM and Flash memories, and you could cheat Murphy by going 3D and replicating the strucure along the Z axis, which is, I believe, what a lot of companies are trying to do right now. Since Moore's law is a speculative observation, and not an induction on any specific first principles in semiconductor technology, the phrasing "Moore's law should apply to X" sort of doesn't make any sense. There's no "should" here because Moore's law doesn't shy why it should apply to any specific type of circuits.

      --
      Ezekiel 23:20
    3. Re:It has not failed yet by RaceProUK · · Score: 3, Insightful

      It's saying Moore's law has failed exactly because it's 18 months later and you would expect 13nm parts by now

      Or a die area twice as large.

      --
      No colour or religion ever stopped the bullet from a gun
    4. Re:It has not failed yet by devjoe · · Score: 2

      Uhhh, the article refers not at all to anything about performance. It refers to the fact that the chip is still using a 19nm process. i.e. the transistors are still 19nm on each side, and because of that, there's the same number of them.

      Actually, it doesn't say that. While they are still using a 19 nm process, they found a way to pack them closer together, and hence there are more of them even though they are still the same size as the previous ones. They didn't say how much closer, though. Packing the units of the same size closer together is the kind of thing you can probably only manage to get useful improvement out of once. Then they'll probably make the chips bigger once, to deliver more transistors. This sounds like the stopgap things you do when the next smaller process won't work, or is too expensive, and they are already talking about stacking them in 3D as the next improvement. But adding another dimension has huge potential. Imagine how many layers you could stack in a 1 mm-high chip if each layer consisted of a 19 nm-thick circuit and a 19 nm-thick insulator.

      I don't think this is really a Moore's Law failure. More like a hiccup, as the new technology needed to continue the growth of Moore's Law gets built up - as has happened multiple times in the decades since Moore stated his famous law.

    5. Re:It has not failed yet by wagnerrp · · Score: 2

      It refers to the fact that the chip is still using a 19nm process. i.e. the transistors are still 19nm on each side

      Nope. It just means they're 19nm on their short edge. The length of their long edge is unbounded. Specifically, the 1X manufacturing process was 19nm x 26nm, while the 1Y process is 19nm x 19.5nm. It's not twice the density, but it is more dense.

    6. Re:It has not failed yet by tlhIngan · · Score: 5, Informative

      Moore's Law applies to the number of transistors in a chip. Just because you have found an increase in performance that did follow Moore's Law for a while does not mean that Moore's Law is somehow about flash memory. Therefore, when the increase no longer follows Moore's Law, it does NOT mean that Moore's Law has failed. The only thing that has failed is your own prediction that things other than the number of transistors would follow that curve.

      And transistors (even floating gate ones - they're just transistors with an extra gate not attached to anything) has a strong correlation with capacity.

      There are two kinds of ICs out there - pin-limited and area-limited. Pin limited ICs are your SoCs and CPUs and such - where the functionality of the entire chip is limited entirely by the number of I/O pads you can stuff on the die and the package while still maintaining adequate yields (the more I/O pads, the more chance of failure during bonding to the package - so while the silicon die may work fine, the attachment to the package didn't).

      Area limited ICs are the opposite - these are where their functionality is limited purely by silicon area. The problem with making a die too big is the increased likelihood of failure caused by wafer imperfections, which decreases yields. As each wafer has a fixed area, a bigger die also reduces the number of ICs you can make from it. So bigger dies lead to lower yields due to imperfections and lower yields due to being able to make less per wafer (the fixed cost is actually pretty large compared to the processing costs).

      Area-limited ICs include camera sensors (you want bigger sensors, but bigger sensors translate directly into lower yields as the sensor matrix has more imperfections ("dead pixels"), lower yields (bad sensors with too many bad pixels, and lower numbers of sensors per wafer), an higher costs (which is why a full-frame dSLR costs way more than one with an APS-sized sensor). Likewise, memory products are also area limited - because if you can use more die area, you can have a larger device. But too large means your high-cap dies are low yields and thus high prices. So to solve this, smaller transistors mean you can pack double the transistors in the same area (per Moore's law) and have practically twice the storage.

      An area-limited IC tends to be very transistor-dense. A pin-limited IC tends to have hotspots of transistor density (embedded memories like caches) which comprise the vast majorities of transistors in a chip, but for the most part, what takes up space on pin-limited ICs is wiring. So much so that wiring tends to be the one spreading transistors out and making them less dense.

    7. Re:It has not failed yet by Lunix+Nutcase · · Score: 5, Informative

      Moore's law which states that computing power (not necessarily transistors) will double every 18 months.

      Wrong. This is what Moore actually said:

      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. That means by 1975, the number of components per integrated circuit for minimum cost will be 65,000. I believe that such a large circuit can be built on a single wafer.

      Notice how it says nothing about "computing power".

  3. self-fulfilling prophecy? by fredrated · · Score: 4, Informative

    I don't think the summary writer knows what that means.

  4. Journalist Wanted Moore Hits by neoshroom · · Score: 4, Informative

    From the article: Some might argue that the die area saving achieved is equivalent to a process node move, and that as Moore's talked about the number of transistors per IC his law is not dependent on a reducing minimum geometries. I think that most will see that this runs against the "spirit" of Moore's Law.

    From Wikipedia: Moore's law is the observation that, over the history of computing hardware, the number of transistors on integrated circuits doubles approximately every two years.

    From article linked off the main article: SanDisk has now revealed that 1Y – now described as a generation rather than a node - is the company's second generation at 19-nm. What the company does claim to have achieved is a reduction in the memory cell size from 19-nm by 26-nm to 19-nm by 19.5-nm, delivering a 25 percent reduction of the memory cell area.

    So, if you can fit more cells using the same size process, it doesn't go against the spirit or the letter of Moore's law. Moore's law is about computing power. If you get more computing power without reducing size to do it, that still counts.

    --
    Big apple, new Yorik, undig it, something's unrotting in Edenmark.
  5. Did anybody really think it could keep going? by hairyfeet · · Score: 2

    And when it comes to NAND we all know the dirty little secret they don't like talking about, with each shrink the lifespan gets shorter so they have to add more and more extra space to replace the dying cells and you end up losing any gains you may have made. That is why I hope something new will end up coming out that will let us have the power saving of SSD with the long life of the HDD, because the consumer level MLC chips frankly aren't very good.

    --
    ACs don't waste your time replying, your posts are never seen by me.
    1. Re:Did anybody really think it could keep going? by unixisc · · Score: 2

      I have a theory that it's the multi-level aspect of them that makes it even worse in every respect except price. As the transistors are shrunk, they become more sensitive to more minor voltage variations, and that degrades when instead of just levels '0' & '1', you have levels of '00', '01', '10' & '11'. So an already bad situation is exacerbated by splitting the already reduced voltages even further. I think that some alternate techniques, such as Spansion's ORNAND, which uses MirrorBit technology where physically separate bits are stored in the source & drain of a transistor, can potentially aleviate this problem. Although the lack of a real ground does tend to introduce its own set of issues

  6. It's not a law ... by gstoddart · · Score: 4, Insightful

    Moore's law has never been a 'law', it's a historical observation.

    It has never claimed that this will be true going forward, merely that at the time it was observed that was the case, and it's largely held up since then.

    The fact that it's held true this long is staggering, but the fact that it might be running out is hardly surprising. Moore never claimed this would continue forever.

    --
    Lost at C:>. Found at C.
    1. Re:It's not a law ... by radarskiy · · Score: 2

      That's what a law is in science. More precisely, it is a relation between observations, in this case device density and time. It is perfectly valid to apply the term to something purely historical and empirical.

  7. Re:NAND flash = transistors on a chip by msauve · · Score: 5, Informative

    It's not just "transistors on a chip." It's a very special type of transistor which is able to store a charge while unpowered. You'll find that Moore's law doesn't apply to power transistors, either - there are fundamental constraints on size due to the need to handle high current.

    It's unreasonable to claim that Moore's law applies to special cases.

    --
    "National Security is the chief cause of national insecurity." - Celine's First Law
  8. Re:er... come again? by iggymanz · · Score: 2

    No, there is no statement about size. only a statement of number of components. Flash has thus been surpassing Moore's law, feature size is irrelevant

  9. Nearing theoretical limit? by wile_e_wonka · · Score: 2

    I am not an engineer. So, you engineers out there--are we nearing the theoretical limit on these things? I mean, 19 nm is pretty darn small. It seems to me that at some point Moore's law has to fail simply because you can't make a connection less than one atom thick. And making a connection one atom thick would be stupid, I would think, for reliability reasons. So--is Moore's law, as extended to NAND flash memory failing due to the fact that it has nearly reached its lowest theoretical size?

    1. Re:Nearing theoretical limit? by wagnerrp · · Score: 2

      Logic transistors still have plenty of life left in them, however NAND flash is a very different beast. The technology works by storing a static charge in a floating gate. The effect of the charge can be measured remotely, but to store the charge, you must use high voltage to bridge the gap across the insulator. This is damaging, which is why flash memory has a limited number of write cycles. The smaller you make the gate, the less charge the gate is able to store, making it harder to read, and the more leaky it is, making it have a shorter life span between refreshes. While the theoretical limit is not known, it's going to be much larger than that of logic transistors, and many believe we will reach it within the next few processing nodes.

  10. It has to fail eventually by rossdee · · Score: 2

    Moore's "Law" has to fail eventually, because if you keep doubling (the amount of transistors on a chip) every couple of years you would soon (in a century or two) have more transitors than there are (elementary) particles in the universe

    Of course we will be up to Windows 95 by then...

  11. Re:NAND flash = transistors on a chip by msauve · · Score: 2

    No, that's not what Moore's law says.

    --
    "National Security is the chief cause of national insecurity." - Celine's First Law
  12. Re:NAND flash = transistors on a chip by camperdave · · Score: 3, Insightful

    It's unreasonable to claim that Moore's law applies at all, because it is not a law, was never a law, and never will be a law. Not in the legal sense, and not in the physical makeup of the universe sense*. Moore's Law is a statistical anomaly. There was never anything preventing any company from developing a technology that packed ten, or twenty, or a hundred times the transistors into the same space as before.

    * Given the persistence of the trend, and the lack of sudden leaps in technology, Moore's law may speak more to human ingenuity than integrated circuit technology.

    --
    When our name is on the back of your car, we're behind you all the way!
  13. Well known issue in the industry by Animats · · Score: 2

    This isn't a new issue to people in the industry. Here's a more useful article from last year: "Is the cost reduction associated with IC scaling over?" "Clearly, dimensional scaling is no longer associated with lower average cost per transistor."

    The cost of wafer fabs has been going up with each generation. Intel says that a cutting-edge fab now costs upwards of $10 billion, twice the previous generation. That's why higher densities no longer reduce cost. The upper limits of optical lithography are being reached because light, even "deep ultraviolet" light, is too coarse a tool. "Extreme ultraviolet" (soft X-rays, really) are being tried to get down to 10nm or so, but the processes are currently slow and barely work. Electron beam machines, which can go below 10nm, have been around since the 1980s, but they work by writing the chip with an electron beam, not with a mask, which is very slow for a production process.

    This is for mostly-static memory. For active transistors, as in CPUs, heat dissipation is already limiting density. CPU clock speed maxed out between 3 and 4 GHz several years ago. (Yes, 8GHz has been achieved with an AMD CPU running in liquid helium. So?)

    With the upper limits of speed and density in sight, work is now focusing on reducing cost and power consumption. Hence the push to use ARM CPUs in more applications.

  14. Re:NAND flash = transistors on a chip by Guppy · · Score: 2

    It's unreasonable to claim that Moore's law applies at all, because it is not a law, was never a law, and never will be a law. Not in the legal sense, and not in the physical makeup of the universe sense*. Moore's Law is a statistical anomaly.

    In other words, it would more correctly be described as "Moore's Observation"?

  15. DDR6 by tepples · · Score: 2

    What about motherboards, BIOS, DDR, harddrives & toasters? Moors law doesn't seem to apply there

    For DDR, it's already up to the limits of how fast the player's feet can move. It took a few years to get from the original Dance Dance Revolution, whose hardest song "Paranoia" had bursts of six steps a second, to the 10 Hz bursts of "Max 300" in DDRMAX: Dance Dance Revolution 6th Mix. It took even longer to get to runs of over 13 Hz in "Fascination Maxx" in Dance Dance Revolution Supernova.