SebNickel
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(cont'd from previous comment)
As I have mentioned at the beginning, the reports up to 2005 contained highly overoptimistic projections for on-chip frequency and supply voltage, which became dramatically more pessimistic in the 2007 edition. The reports clearly state, however, that these numbers are meant as targets and are not necessarily "on the road to sure implementation", especially where it has been highlighted that solutions were needed and not yet known. They can therefore not necessarily serve as a clear indictment of the ITRS' predictive powers, but I remain puzzled by some of their projections and comments on these before 2007. Getting clarification on this from industry insiders was the next thing I... (read 818 more words →)
(cont'd from previous comment)
Did the industry predict these problems and their consequences?
People in the industry were well aware of these limitations, long before they actually became critical. However, whether solutions and workarounds would be found was a matter of much greater uncertainty.
Robert Dennard et al's seminal 1974 paper Design of Ion-Implanted MOSFETs with Very Small Physical Dimensions, that described the very favourable scaling properties of MOSFET transistors and gave rise to the term "Dennard scaling", explicitly mentions the scaling limitations posed by subthreshold leakage:
... (read 610 more words →)One area in which the device characteristics fail to scale is in the subthreshold or weak inversion region of the turn-on characteristic. (…) In order to design devices for
I'm having a remote researcher look through this for another project, and will try to remember to report back here when that analysis is done.
That project has been on hold for close to a month, the reason being that we wanted to focus on other things until we get hold of the 1994, 1997 and 1999 editions of the ITRS roadmap report that it should be possible to order through the ITRS website. However, we never heard back from whoever monitors the email address that you're supposed to send the order form to, nor were we able to reach anyone else willing to sell us the documents...
I am happy to report on... (read 1266 more words →)
Thanks! But as you know my overview you link to is about the breakdown of Dennard Scaling, which is related to but really quite distinct from Moore's Law. I'm not sure how much this matters, but it struck me as misleading.