The end of Moore’s law - The Computing Universe: A Journey through a Revolution - page 300

of the quantum mechanical into the classical data storage regime and we
reached this limit at 12 atoms. 5

The groups of atoms were arranged using an STM operating at very low tem-
peratures. By scaling up these twelve-atom bits to a few hundred atoms, it may
be possible to make such structures stable at room temperature. Clearly, how-
ever, volume production of such memory devices is many years away.
In his 1986 topic Engines of Creation , the nanotechnology researcher Eric
Drexler ( B.15.2 ) envisages a future in which self-replicating nanomachines
could be engineered that could create almost any type of matter ( Fig. 15.7 ).
In his vision of a nanotechnology-powered future, hunger would be elimi-
nated, all diseases cured, and the human life span extended dramatically.
Drexler uses the term grey goo to refer to an out-of-control, spreading mass of
self-replicating machines that could literally cause the end of the world. Bill
Joy, one of the founders of Sun Microsystems, became so concerned about the
potentially catastrophic effects of Drexler's nanomachines that he warned
against unregulated experimentation with nanotechnology in Wired maga-
zine. Fortunately, while Drexler's topic certainly excited many people about
the future potential of nanotechnology, most scientists believe that we are a
long way from actually creating any of Drexler's self-assembling machines.

Fig. 15.4. IBM researchers Don Eigler
and Erhard Schweizer spelled out the
initials of the company in thirty-five
individually positioned xenon atoms in
1989.

The near future

Fig. 15.5. A stadium-shaped “quantum
corral” was built by positioning individ-
ual iron atoms on a copper surface.

As Gordon Moore acknowledged in 2005 (see Chapter 7 ), the size of tran-
sistors is “approaching the size of atoms which is a fundamental barrier” 6 for
present-day technology. Each year, a group of semiconductor experts in the five
leading chip-manufacturing regions in the world - the United States, Japan,
Taiwan, South Korea, and Europe - prepare a report called the International
Technology Roadmap for Semiconductors (ITRS), which identifies the challenges for
the future of semiconductor chip manufacturing. In past years, the roadmap
has laid out research and development targets necessary for the continuation
of geometrical scaling , the continued reduction in size predicted by Moore's law.
Now, however, the roadmap also includes equivalent scaling , improving perfor-
mance through innovative design, software solutions, and new materials or
structures. The 2012 version of the ITRS looks at both near-term goals, through

Fig. 15.6. In 2012, IBM researchers built
a magnetic memory device consisting of
just twelve atoms.

B.15.2. Eric Drexler is known for his theoretical work on molecular nanotechnology. He devel-
oped the concept of self-assemblers capable of constructing molecules atom by atom. This idea not
only captured the imagination of science fiction writers but also created real research interest in
this field. There are many skeptics of Drexler's ideas and the research has not demonstrated the
possibility of building nanoscale self-assemblers.