The Incredible Shrinking Circuit; September 2001; Scientific American Magazine; by Charles M. Lieber; 7 Page(s)

Do we really need to keep on making circuits smaller? The miniaturization of silicon microelectronics seems so inexorable that the question seldom comes up-except maybe when we buy a new computer, only to find that it becomes obsolete by the time we leave the store. A state-of-theart microprocessor today has more than 40 million transistors; by 2015 it could have nearly five billion. Yet within the next two decades this dramatic march forward will run up against scientific, technical and economic limits. A first reaction might be, So what? Aren't five billion transistors enough already?

Yet when actually confronted with those limits, people will no doubt want to go beyond them. Those of us who work to keep computer power growing are motivated in part by the sheer challenge of discovering and conquering unknown territory. But we also see the potential for a revolution in medicine and so many other fields, as extreme miniaturization enables people and machines to interact in ways that are not possible with existing technology.