In case you’ve been living under a rock and don’t know this, in 1965, Intel co-founder Gordon E. Moore predicted that the number of transistors on an integrated circuit would double approximately every two years. Empirically based on economic factors as well as technical ones, his observation and conclusion has been so accurate that it has been given the title “Moore’s Law.” Certain pundits continually predict that we are reaching the end of the trail, and that the trend cannot continue because miniaturization technology will reach its limit. (It should be noted that Moore’s Law doesn’t specify the size of the IC die; logically one should be able to fit more transistors on a larger die – but that’s another story.)
The Ivy Bridge architecture, which utilizes a 22 nanometer fabrication process, comprises Intel’s product offerings for 2012. The firm’s next generation micro-architecture, code named Haswell, is expected to arrive in 2013 and will continue to use the 22 nm process. In 2014, the process will be shrunk to 14 nm with Roswell. Down the road, the process is expected to shrink even more, getting down to 10 nm by 2018.
How long can this go on?
Well, there is certainly at least one real limit, which is the size of the transistors themselves. A combined team of researchers from the University of New South Wales, the University of Melbourne and Purdue University has recently created a functional transistor comprising a single phosphorus atom. Furthermore, they have also developed a wire made from a combination of phosphorus and silicon, one atom tall and four atoms wide, that behaves like a copper wire. Granted, this technology is far from practicable at this point in that it has to be maintained at a temperature of minus 391 degrees F, but it does show what is possible.
As circuits get smaller and smaller, other laws of physics come into play, causing additional technical problems. Dr. Michio Kaku (surely you’ve seen him on TV - if not, you should!) of CCNY says that, once transistors shrink to 5 atoms wide (projected for 2020) the Heisenberg Uncertainty Principle will come into play. This states that it is not possible to know both the position and velocity of any particle; that one can only know one or the other. Thus one cannot know precisely where an electron actually is, and therefore cannot confine it to a wire. Since free electrons can’t be allowed to go bouncing about in any logic circuit because they may cause shorts (or, at least, logical errors), this may prove to be a practical limit.
Some pundits have theorized, though, that getting down to these sizes may allow the development of true quantum computing, wherein information is processed on a more-than-binary level. This remains to be seen.
There’s a lot of interesting stuff going on in this space. Some practical, some not so much. Stay tuned, as I plan to do a couple of additional blogs on this subject before I retire sometime next year.