What Is Nanotechnology?

In the early 20th century, Henry Ford built a car manufacturing plant on a 2,000-acre tract of land along the Rouge River in Michigan. Built to mass-produce automobiles more efficiently, the Rouge housed the equipment for developing each phase of a car, including blast furnaces , a steel mill and a glass plant. More than 90 miles of railroad track and conveyor belts kept Ford's car assembly line running. The Rouge model was lauded as the most efficient method of production at a time when bigger meant better.

The size of Ford's assembly plant would look strange to those born and raised in the 21st century. In the next 50 years, machines will get increasingly smaller -- so small that thousands of these tiny machines would fit into the period at the end of this sentence. Within a few decades, we will use these nanomachines to manufacture consumer goods at the molecular level, piecing together one atom or molecule at a time to make baseballs, telephones and cars. This is the goal of nanotechnology . As televisions , airplanes and computers revolutionized the world in the last century, scientists claim that nanotechnology will have an even more profound effect on the next century.

Nanotechnology is an umbrella term that covers many areas of research dealing with objects that are measured in nanometers . A nanometer (nm) is a billionth of a meter, or a millionth of a millimeter.

Manufactured products are made from atoms. The properties of those products depend on how those atoms are arranged. If we rearrange the atoms in coal we can make diamond. If we rearrange the atoms in sand (and add a few other trace elements) we can make computer chips. If we rearrange the atoms in dirt, water and air we can make potatoes.

Todays manufacturing methods are very crude at the molecular level. Casting, grinding, milling and even lithography move atoms in great thundering statistical herds. It's like trying to make things out of LEGO blocks with boxing gloves on your hands. Yes, you can push the LEGO blocks into great heaps and pile them up, but you can't really snap them together the way you'd like.

In the future, nanotechnology will let us take off the boxing gloves. We'll be able to snap together the fundamental building blocks of nature easily, inexpensively and in most of the ways permitted by the laws of physics. This will be essential if we are to continue the revolution in computer hardware beyond about the next decade, and will also let us fabricate an entire new generation of products that are cleaner, stronger, lighter, and more precise.

It's worth pointing out that the word "nanotechnology" has become very popular and is used to describe many types of research where the characteristic dimensions are less than about 1,000 nanometers. For example, continued improvements in lithography have resulted in line widths that are less than one micron: this work is often called "nanotechnology." Sub-micron lithography is clearly very valuable (ask anyone who uses a computer!) but it is equally clear that conventional lithography will not let us build semiconductor devices in which individual dopant atoms are located at specific lattice sites. Many of the exponentially improving trends in computer hardware capability have remained steady for the last 50 years. There is fairly widespread belief that these trends are likely to continue for at least another several years, but then conventional lithography starts to reach its limits.

If we are to continue these trends we will have to develop a new manufacturing technology which will let us inexpensively build computer systems with mole quantities of logic elements that are molecular in both size and precision and are interconnected in complex and highly idiosyncratic patterns. Nanotechnology will let us do this.

When it's unclear from the context whether we're using the specific definition of "nanotechnology" (given here) or the broader and more inclusive definition (often used in the literature), we'll use the terms "molecular nanotechnology" or "molecular manufacturing."

Whatever we call it, it should let us

The requirement for low cost creates an interest in self replicating manufacturing systems , studied by von Neumann in the 1940's. These systems are able both to make copies of themselves and to manufacture useful products. If we can design and build one such system the manufacturing costs for more such systems and the products they make (assuming they can make copies of themselves in some reasonably inexpensive environment) will be very low.

Photo courtesy NASA, Ames
Nanogears no more than a nanometer wide could be used to construct a matter compiler, which could be fed raw material to arrange atoms and build a macro-scale structure.

A New Industrial Revolution

Nanotechnology is likely to change the way almost everything, including medicine, computers and cars, are designed and constructed. Nanotechnology is anywhere from five to 15 years in the future, and we won't see dramatic changes in our world right away. But let's take a look at the potential effects of nanotechnology:

The first products made from nanomachines will be stronger fibers. Eventually, we will be able to replicate anything, including diamonds , water and food. Famine could be eradicated by machines that fabricate foods to feed the hungry.

The promises of nanotechnology sound great, don't they? Maybe even unbelievable? But researchers say that we will achieve these capabilities within the next century. And if nanotechnology is, in fact, realized, it might be the human race's greatest scientific achievement yet, completely changing every aspect of the way we live.