What is Nanotechnology?

A scientific and technical revolution has begun that is based upon the ability to systematically organize and manipulate matter on the nanometer length scale.

Examples of nanotechnology applications:

• giant magnetoresistance in nanocrystalline materials
• nanolayers with selective optical barriers, hard coatings
• dispersions with optoelectronic properties, high reactivity
• chemical and bio-detectors
• advanced drug delivery systems
• chemical-mechanical polishing with nanoparticle slurries
• new generation of lasers
• nanostructured catalysts
• systems on a chip
• carbon nanotube products
• nanoparticle reinforced materials
• thermal barrier
• ink jet systems
• information recording layers
• molecular sieves
• high hardness cutting tools

What is a nanometer?

A nanometer is one billionth of a meter (10-9 m). This is roughly ten times the size of an individual atom. A cube 2.5 NM on a side would contain about a thousand atoms. The smallest feature in an integrated circuit of today is 250 NM on a side, and contains one million atoms in a layer of atomic height. Proteins, the molecules that catalyze chemical transformations in cells, are 1 to 20 NM in size. For comparison, 10 NM is 1000 times smaller than the diameter of a human hair. There are as many nanometers in an inch as there are inches in 400 miles.

Why is this length scale so important?

There are five reasons why this length scale is so important:

• The wavelike properties of electrons inside matter are influenced by variations on the nanometer scale. By patterning matter on the nanometer length scale, it is possible to vary fundamental properties of materials (for instance, melting temperature, magnetization, charge capacity) without changing the chemical composition.

• The systematic organization of matter on the nanometer length scale is a key feature of biological systems. Nanotechnology promises to allow us to place artificial components and assemblies inside cells, and to make new materials using the self-assembly methods of nature. This is a powerful new combination of materials science and biotechnology.

• Nanoscale components have very high surface areas, making them ideal for use in composite materials, reacting systems, drug delivery, and energy storage.

• The finite size of material entities, as compared to the molecular scale, determine an increase of the relative importance of surface tension and local electromagnetic effects, making nanostructured materials harder and less brittle.

• The interaction wavelength scales of various external wave phenomena become comparable to the material entity size, making materials suitable for various opto-electronic applications.

Is this really new?

Many existing technologies depend crucially on processes that take place on the nanometer scale. Photography and catalysis are two examples of "old" nanotechnologies, which arose despite the limited ability of the times to probe and control matter (and which stand to be improved vastly as nanotechnology develops). What is new is the ability to specifically analyze, organize, and control matter on many length scales simultaneously. For over a century, chemists have developed the ability to control the arrangement of small numbers of atoms inside molecules (length scale of less than 1.5 NM), leading to revolutions in drug design, plastics, and many other areas.

Over the last several decades, photo-lithographic patterning of matter on the 1000 NM length scale has led to the revolution in microelectronics. With nanotechnology, it is possible to bridge this gap, and to control matter on every important length scale, enabling tremendous new power in materials design. (The most complex arrangements of matter we know of, living organisms, require specific patterns of matter on the molecular, nanometer, micron, millimeter, and meter scale, all at once.) Furthermore, by tailoring the structure of materials in the range about 10-9 to 10-7 m one can systematically and significantly change specific properties at larger scales: material behavior can be engineered. Larger systems constructed of nanometer-scale components can have entirely new properties that have never before been identified in nature. It is also possible to produce composites that combine the most desirable properties of very different materials to obtain characteristics that are greatly improved over those that nature supplies or that appear in combinations nature does not produce.

Thus, nanotechnology actually represents a revolutionary super-field that will eventually become a foundation for such currently disparate areas as inks and dyes, protective coatings, medicines, electronics, energy storage and usage, structural materials, and many others that we cannot even anticipate. Investigations at nanoscale were left behind as compared to molecular and bulk length scales because significant developments of the corresponding investigative tools have been made only recently.

How will the new technologies help solve society problems?

The new concepts of nanotechnology are so broad and pervasive, that they will influence every area of technology and science, in ways that are surely unpredictable. We are just now seeing the tip of the iceberg in terms of the benefits that nanostructuring can bring:

• wear-resistant tires made by combining nanometer-scale particles of inorganic clays with polymers
• medicines as nanoparticles with vastly improved delivery and control characteristics
• greatly improved printing brought about by nanometer-scale particles that have the best properties of both dyes and pigments, and
• vastly improved lasers and magnetic disk heads made by controlling layer thickness to better than a nanometer.

Nanometer-scale traps will be constructed that will be able to remove pollutants from the environment and deactivate chemical warfare agents. Computers with the capabilities of current workstations will be the size of a grain of sand and will be able to operate for decades with the equivalent of a single wristwatch battery. Robotic spacecraft that weigh only a few pounds will be sent out to explore the solar system, and perhaps even the nearest stars.

What will government do for nanotechnology?

Government will play the key role in assuring that the enormous benefits of nanotechnology will be realized quickly and the U.S. will share the global benefits. The goals of nanotechnology are too long term (greater than ten years) for industry to take an immediate leadership role, although the high level of industry interest and concern for the field is almost unprecedented. Because of its interdisciplinary nature, the development of nanotechnology requires creating teams of physicists, chemists, biologists, and engineers to tackle the problems, and the funding agencies will need to be organized to foster this teamwork. The enabling infrastructure and technologies must be in place for industry to take advantage of nanotechnology innovations and discoveries. Industry is frequently reluctant to invest in risky research that takes many years to develop into a product. In the US the university and government research system fills this gap. The increasing pace of technological commercialization requires a compression of past time scales and parallel development of research and commercial products and a synergy among industry, university, and government partners. New infrastructure at the universities and national labs is required for the field to grow. A worldwide competition is underway, and the US response is fragmented in comparison to the approach of European and Asian countries. For all of these reasons, this is a moment of opportunity to create an inter-agency initiative in nanotechnology to catalyze academe, industry, health, business, and national security efforts.

Looking to the future

The total societal impact of nanotechnology is expected to be greater than the combined influences that the silicon integrated circuit, medical imaging, computer-aided engineering,and man-made polymers have had in this century. Significant improvements in performance and changes of manufacturing paradigms will lead to several industrial revolutions in the 21st century. Nanotechnology will change the nature of almost every human-made object. The major questions now are how soon will these revolutions arrive, who will benefit the most, and who will be in position to control or counter their negative aspects? How can we embrace and facilitate the new industrial revolution to maximize the benefit to US citizens? We believe that a national initiative is required to advance this goal because the needs for and from nanotechnology transcend anything that can be supplied by traditional academic disciplines, national laboratories, or even entire industries.

The text of the previous sections is taken from the introduction to "Vision for Nanotechnology R&D in the Next Decade" prepared by the workshop organizing committee of the Interagency Working Group on Nano Science, Engineering and Technology (IWGN) Workshop held January 27-29, 1999.