…twice the number of components won’t appear on the next IC chip (Part 1 of 4)
Gordon Moore always calls it “so-called Moore’s Law” when discussing his eponymous observation about IC scaling trends, and he has always acknowledged that it’s no more and no less than a marketing tool used to inform an ecosystem of downstream chip-users of price:performance improvements planned. The original observation published in 1965 and updated in 1975 established that the number of functional circuit components—including transistors, diodes, and any passive components—on a single IC chip doubled periodically.
When Moore updated this in 1975 (Moore, Gordon. “Progress in Digital Integrated Electronics” IEEE, IEDM Tech Digest (1975) pp.11-13.) he decomposed the sources of increasing component count as follows:
- Die size increase,
- Dimension decrease (a.k.a. “shrink”),
- Device and Circuit design (a.k.a. “cleverness”).
Note that Moore never said anything about cost, speed, power-consumption, or reliability. It was left to the IC sales guys to inform that lithographic R&D meant that the next generation chips would actually be smaller and cost less, and most importantly the ability to maintain Dennard Scaling with power-reduction/transistor rules meant that each chip reliably consumed less power. This was the glory era when each new chip generation provided it all: more components, faster speed, and cheaper price.
Five years ago, Gordon Moore and Jay Last provided an insightful review of the founding of the IC industry at the Computer History Museum, which I covered in an independent blog posting (http://www.betasights.net/wordpress/?p=758). As well summarized in the “Transistor Count” entry at Wikipedia (https://en.wikipedia.org/wiki/Transistor_count) by 1975 the industry was working on designs with 10k transistors, and 100k by 1982, and 1 million by 1989. Incredibly, the trend continued to 1 billion transistors on a chip in production in 2010.
In my interview with Gordon Moore published in the July 1997 issue of Solid State Technology, he emphasized two points: the atomic limits of IC manufacturing, and the fact that when we start to reach atomic limits we’ll be able to put 1 billion circuit elements into a square centimeter of silicon. However, henceforth we will no longer get it all with the next generation chips, and will only be able to choose one from the glory list that used to be a package deal (pun intended): more, faster, cheaper. IC innovation will certainly continue, but it will not come through smaller and faster and cheaper circuit elements. Moore’s accurate prediction of gigascale circuitry on cheap chips explicitly sets the stage for the next 50 years of innovation in IC manufacturing…we’ve only begun to play with billions of transistors.
Make no mistake, everyone wishes that Moore’s Law was still alive and well. IC fabs most of all, but everyone from economists and politicians promising exponential growth (http://www.foreignpolicy.com/articles/2010/10/11/opening_gambit_moores_flaw) to futurists selling absurd fantasies of benevolent nanobots (http://www.singularity.org) deeply wish that Moore’s Law would continue. Sadly, no exponential in the real world can go on forever, and we make mistakes when we blindly ignore changing conditions behind an exponential trend.
More than ever before, people with little understanding of what Gordon Moore said let alone what he meant try to discuss the ramifications of an eventual end to Moore’s Law. In particular, people who have never worked in a semiconductor fab nor designed a commercial IC love extrapolating prior trend-lines forward without an understanding of how we got here nor a clue about the real atomic and economic limits of IC production.
Some analyses ignore the realities of manufacturing process control (http://www.mooreslaw.org/) while others revel in extrapolations based on mathematical abstractions and economic theories (http://www.ebnonline.com/author.asp?section_id=3315&doc_id=273652), and such work can be so bad that it is “not even wrong”.
Imminent posts in this blog series will discuss:
Moore’s Law is Dead – (Part 2) When we reach economic limits,
Moore’s Law is Dead – (Part 3) Where we reach atomic limits,
Moore’s Law is Dead – (Part 4) Why we say long live “Moore’s Law”!
—E.K.
It may be that our thinking will shift to calculations per second, and incorporate Trinary, crystals and harness light in new ways to keep Mr. Moore happy.
Industry has already shifted to discussing caluculations per second, flash memory multi-level cells already use 3 levels, silicon and all alternate channel materials are crystals, and people are already working on integrated photonics (all of which should allow innovation to continue…without doubling the number of components per chip).
Well Moore’s law was declared dead 25 and 5 years ago, 20 and 10 years ago, and all the years in between. There was no shortage of prophets who declare the law dead.
I guess will keep watching the show going forward, I bet 10 years and 20 years from now new prophets will start declaring Moore’s law dead.
Well, prior pundits lacked the current perspective on the economic limits imposed by lithography, as well as the scaling limits imposed by atoms…as future posts in this series will detail.
“We” know the scope of Moore’s Law is semiconducting device technology. The pundits and futurists, e.g. Kurtzweil, use the term to define “technology evolution” which is geometric and by some calculations, accelerating. And is not restricted to semiconductors.
Everyone knows that the smallest device that can be built must be composed of atoms, and in Part-3 of this blog series I’ve shown that the smallest nanotube array we can theoretically build and possibly interconnect would be ~4nm pitch. Electronic circuit speeds are already limited by the lack of room-temperature superconductors and the lag in photo-electric conversion. No one has shown anything close to 4nm pitch optical circuits nor magnetic circuits that can compete with let alone surpass electronic circuits (except for niche applications). What else might we use for digital logic and memory?
Kurtzweil was smart enough in the mid-1970s to rely on Moore’s Law acceleration of IC processing power through the end of the century to create first OCR and text-to-speach then decent music synthesis, and acquired deserved money and fame; however, Kurtzweil and comparible “futurists” lack experience in IC manufacturing technology, and their main business seems to be selling science fantasy (an honorable entertainment business IMHO but not to be confused with engineering or technology).
I would say: New geometry nodes are very hard won, so the economic ROI becomes tougher to rationalize. This should force the industry to innovate more on circuits and architecture rather than simply ride the Moore’s Law wave. I think the semicon industry overall has become complacent. The over-emphasis on process geometry has put companies like TSMC in control of the industry’s profits (ask any small semi company how they are paying 2-3x for the same wafers that Broadcom uses), and has caused VCs to walk away from semis. Reset in value prop is required!
Good points. A relative shift in the IC value-add from manufacturing to design could indeed trigger more investment in fabless start-ups.