NANOTECHNOLOGY—TECHNOLOGY ON A MOLECULAR SCALE - Chemistry: Notable Research and Discoveries - page 39

Believing that no law of physics prohibits small-scale technologies, Feyn-
man argued, “I am not inventing anti-gravity, which is possible someday
only if the laws are not what we think.” In contrast to something that
violates the laws of physics as they are currently understood, decreasing
the size of devices was feasible. In other words, in Feynman's creative lan-
guage, people had room with which to work at the low end (bottom) of
the size scale, and the reason nobody had done it was “simply because we
haven't yet gotten around to it.” A highly respected physicist, Feynman
won a share in the 1965 Nobel Prize in physics for his work on applying
quantum mechanics to electromagnetic phenomena.
Feynman's idea was a little ahead of its time, but in 1986 the Amer-
ican engineer Eric Drexler published a topic, Engines of Creation, in
which he popularized the development of small-scale technologies.
Drexler had been influenced by Feynman's lecture but took the idea
further, sparking the imagination and curiosity of other engineers and
scientists. People had been thinking about this subject earlier—the
Japanese physicist Norio Taniguchi coined the term nanotechnology in
1974—but Drexler's enthusiasm was important in calling attention to
the field.
Nanotechnology takes its name from the nanometer, which is a bil-
lionth of a meter. ( Nanos is a Greek word meaning dwarf or midget.)
A nanometer is about 0.00000004 inches (0.0000001 cm). It is difficult
to visualize such a tiny length. Imagine taking a piece of paper one inch
(2.5 cm) long and dividing it into 25,000,000 segments, each segment of
which will be a nanometer. This length is much smaller than anything
people experience in everyday life. A gnat, for instance, is about 0.1 inches
(0.3 cm), and the diameter of a human hair is roughly 30 times smaller.
Bacteria are 10-50 times smaller than the diameter of a human hair, and
a nanometer is 5,000 times smaller than the average size of a bacterium.
Roughly 10 atoms would fit along the length of a nanometer.
In the most common definition, nanotechnology refers to any tech-
nology or device on the scale of about 1-100 nanometers. Microscopes
that use light are not useful in this range because the wavelength of vis-
ible light exceeds these magnitudes, and distortion due to diffraction—
the scattering of light rays—obscures the image of objects of this size.
Researchers turn instead to electrons. The German engineers Ernst
Ruska (1906-88) and Max Knoll (1897-1969) invented the electron mi-
croscope in the 1930s; this microscope creates images by passing a beam
of electrons through a sample, or sometimes reflecting electrons from