Nanotech: Small Products, Big Potential
Maybe Walt Disney was right: "It's a small world after all." His popular theme park ride debuted 40 years ago at the 1964 New York World's Fair. Since then, it has thrilled millions of visitors to Disneyland and Disney World. Within 10 minutes, people are magically transported around the world and exposed to numerous cultures.
Today, that small world is becoming even smaller, thanks to nanotechnology-the science of building devices at the scale of individual molecules. Nanotechnology promises to transform the way thousands of products are designed and assembled. Many experts claim that it will revolutionize traditional industries such as automotive, aerospace, appliance, electronics, medical devices and consumer products. And, like the electric motor, the transistor and the microchip, nanotech may spawn entirely new industries.
By manipulating individual atoms and molecules, nanotechnology makes it possible to significantly enhance a material's natural properties, ranging from strength and electrical conductivity to optical, magnetic and thermal qualities. It's also possible to create entirely new materials, properties and systems.
During the next 10 years, nanotechnology will go from the laboratory to the marketplace. "Nanotechnology may be the science of very small things, but it's going to play a huge role in our future technological and economic development," claims David Peyton, technology policy director at the National Association of Manufacturers (Washington, DC).
"American consumers are already enjoying the benefits of nanotech without realizing it," adds Peyton. "Automobiles alone contain nanotech applications from new paint finishes to improved catalytic converters. The future possibilities across the economy are endless."
Within the next decade, the National Science Foundation (Arlington, VA) predicts that the worldwide nanotechnology market will reach $1 trillion. As a result, thousands of manufacturers are pouring millions of dollars into R&D efforts. Companies leading the charge include BASF, Boeing, DaimlerChrysler, DuPont, Hewlett-Packard, IBM and Motorola.
In addition, nanotechnology has attracted more than $1 billion in venture capital over the last 3 years as numerous start-up companies vie for a slice of the pie. Universities from coast to coast have established nanotech research facilities. Scientists at federal laboratories are also developing new applications.
A recent initiative by the federal government should add fuel to the fire. In early December, President Bush signed the 21st Century Nanotechnology Research and Development Act. It authorizes $3.7 billion in R&D funding over a 4-year period beginning in FY 2005. According to F. Mark Modzelewski, executive director of the NanoBusiness Alliance (New York), it's the highest federally funded science and technology effort since NASA's Apollo program in the 1960s.
"The buzz surrounding nanotech is comparable to that at the dawn of the digital revolution, which changed the face of how business operates," claims Jack Uldrich, president of Nano Veritas Group (St. Paul, MN). "Unlike the Internet, however, which applied new technology to many old processes and businesses, nanotech is about creating entirely new materials, products, systems and markets, as well as making existing products faster, stronger and better."
Because of nanotechnology, Uldrich claims that all manufacturers need to rethink what their core business is, who their competitors are and how they conduct strategic long-range planning. "Everything in our world is made of atoms," says Uldrich, who is the coauthor of The Next Big Thing Is Really Small (Crown Business). "And with the ability to manipulate those atoms, the rule of the game for almost every business will be dramatically changed."
Smaller Than Small
Nanotechnology is a generic term that refers to the art and science of rearranging individual atoms and molecules to create useful materials, devices and systems. One nanometer is one-billionth of a meter, which is approximately the width of 10 hydrogen atoms. The width of the dot above the letter "i" in this sentence is approximately 1 million nanometers. The diameter of an average hair is 50,000 nanometers.
Through nanotechnology, objects are built in a way that nearly each atom is precisely placed the way each brick might be laid when constructing a 10-story building. "Nanotechnology is engineering design at the level of atoms and molecules," says Carl Jennings, executive vice president of BASF Corp. (Mount Olive, NJ). "When materials are prepared on a nanoscale, the amount of exposed surface area increases dramatically. For example, a 1-foot cube has a surface area of 6 square feet. However, this same volume of material, divided into nanometer cubes, has a potential surface area of 6 square miles, or nearly 4,000 acres.
The nanotech world revolves around buckyballs and nanotubes. Buckyballs are geodesic spheres named for visionary engineer R. Buckminster Fuller, inventor of the geodesic sphere. Buckyballs are strong and rigid natural molecules that resemble soccer balls. One individual buckyball comprises exactly 60 carbon atoms. Because they are made of virtually unbreakable, impenetrable carbon, with many attachment points for drugs, buckyballs have vast potential for biomedical R&D.
Nanotubes are tiny, hollow cylinders with outside diameters of a mere nanometer, formed spontaneously from atoms such as carbon. Like many structures at the nanoscale, carbon nanotubes exhibit properties that seem bizarre and contradictory, at least in the eyes of the average human. Aligned in a certain way, their atoms may conduct electricity as effectively as copper. Aligned in a slightly different way, they are electrical semiconductors-midway between conductors and insulators.
Nanotubes are also stronger than steel, so long filaments could create super tough, fiber-reinforced plastics and other lightweight materials. Multiwall nanotubes have been manipulated to perform as extremely low friction nanoscale linear bearings and constant-force nanosprings.
Nanotechnology traces its roots to the pioneering work of physicist Richard Feynman. In 1959, he delivered a landmark speech in which he proposed a link between biology and manufacturing. He explained how biological cells manufacture substances. He urged his audience to "consider the possibility that we, too, can make a thing very small, which does what we want-that we can manufacture an object that maneuvers at that level."
A milestone in nanotechnology was reached in 1981, when physicists Heinrich Rohrer and Gerd Binning invented the scanning tunnel microscope, a feat that brought them a Nobel Prize in 1986. Their new type of electron microscope magnified objects 10 million times, enabling scientists to look at individual molecules and atomic surface structures for the first time. Another breakthrough occurred in 1996, when Richard Smalley received the Nobel Prize in chemistry for his discovery of buckyballs.
Since then, researchers have been developing the technology to create customized materials molecule by molecule, atom layer by atom layer, producing new characteristics or effects. Most efforts have focused on nanomanipulation, or building things from the bottom up, atom by atom.
Nanomanipulation can be classified into two categories: Nanofabrication and self-assembly. Nanofabrication refers to the actual sculpting or building, with man-made tools, of products, structures and processes with atomic precision. Self-assembly is the process of atoms and molecules adhering in a self-regulated fashion, whereby specific atoms and molecules bind to one another based on their size, shape, composition or chemical properties.
So far, most nanotech activity has focused on developing sensors, coatings, polymers, films and membranes. Examples include scratch-resistant paint, self-cleaning windows and stain-resistant fabrics. Products currently on the market include include chemicals produced with microscopic catalytic particles, sun lotions with invisibly small zinc-oxide flakes to shield against ultraviolet rays, emulsifiers that keep paint from separating, and coatings that make eyeglass lenses more scratch resistant or extend the life of industrial tools.
Thousands of new products are being developed in labs around the world. However, many will take a few years to reach the market because new manufacturing systems also must be developed. In the near future, nanoproducts will include smaller, faster and more efficient computers; medicines that target the molecular errors that cause disease while leaving healthy cells unharmed; lamps that use one-tenth as much energy as lightbulbs and never burn out; and new products and materials created with a molecular-level precision that have properties well beyond what can be manufactured today.
Engineers at Samsung Electronics Co. (Seoul, South Korea) are working on supersharp flat-screen displays for televisions, computers and handheld devices. An array of nanotubes emitting electrons at the screen's backside would use just a fraction of the power of traditional LCDs. Samsung hopes to ship its first nanotube TVs by the end of this year.
Nanotechnology also promises to revolutionize the battery industry. Batteries made with carbon nanotubes and nanoscale lithium particles could store more energy in less space, last twice as long and recharge faster.
A University of Tulsa chemistry professor was recently awarded a U.S. patent for a manufacturing process for nanobatteries. Dale Teeters and his research assistants have made batteries so small that more than 40 could be stacked across the width of a hair. Each battery contains up to 3.5 volts.
In addition to electronics, the auto industry will reap numerous benefits from nanotechnology. Possibilities include surfaces treated with nanoparticles that could improve the hardness and the friction properties of engines and transmissions; nanosilicate lamellae that could suppress the evaporation of hydrocarbons in plastic tanks; nanoporous filters that could reduce pollutant emissions; nanoparticles of soot and silicate that could be added to rubber mixtures to improve the grip of tires and extend their lives; and electronic parts based on nanostructures that could be used in highly sensitive sensors to monitor a vehicle's surroundings and passenger compartment.
"Cars that can change color like a chameleon or even alter the shape of their bodywork at the touch of a button may still be visions of a relatively distant future," notes Ulf Konig, head of the electronics and mechatronics research section at DaimlerChrysler Research (Ulm, Germany). "However, such clever vehicles remain fascinating because they can no longer be simply ruled out as wishful thinking. Despite its visionary quality, the idea of a car that can change its color or reshape its body has a realistic underpinning-nanotechnology."
Konig claims that nanotechnology will lead to numerous innovations for the auto industry in the years ahead. "Nanotech is an interdisciplinary area that will benefit not only electronics and the classic vehicle construction process, but also the drivetrain and energy conservation," he points out.
According to Konig, one of the most widely known benefits of nanotechnology is the "lotus effect," which makes self-cleaning surfaces possible. Thanks to the lotus flower's extremely fine surface structure, water and dirt roll off the petals without leaving a trace. DaimlerChrysler is applying the same lotus effect to its efforts to develop self-cleaning wheel rims and self-cleaning body paint that will eliminate the need for a car wash. Konig and his team are also developing a solar coating that will be sprayed on like paint or glued on like film. The goal is to turn a car's body into one big mobile solar cell.
Engineers at Boeing Co. (Chicago) are using nanotechnology to develop structural amorphous metals. These lab-produced materials deliver titanium's strength over a wide temperature range in a much lighter material. According to David Bowden, a technical fellow at the company's Phantom Works, Boeing's first-generation aluminum alloys have registered a tensile strength of 120,000 psi, which is approximately 25 percent greater than the strength of traditional aluminum.
"Having control of the material's structure at the atomic level gives you much more power to improve properties," notes Bowden. "Metals we use today are crystalline materials, with individual atoms arranged in a regular, ordered structure."
The engineers discovered that some alloys, when solidified from the molten state, form a noncrystalline amorphous material or metallic glass. With controlled thermal treatments of the glass, engineers can manipulate these new alloys to create unique materials with nanoscale microstructural features.
One of the most intriguing aspects of nanomanufacturing involves self-assembly. It is a subset of nanotechnology that refers to the natural tendency of certain individual elements to arrange themselves into regular nanoscale patterns. A tree constructing itself out of the surrounding molecules in the air, water and dirt is an example, from Mother Nature, of self-assembly.
As engineers reach the limits of working with silicon, carbon nanotubes are widely recognized as the next step in squeezing an increasing number of transistors onto a chip, vastly increasing computer speed and memory. "Self-assembly opens up new opportunities for patterning at dimensions smaller than those in current technologies," says T.C. Chen, Ph.D., vice president of science and technology at IBM Research (Armonk, NY). "As components in information technology products continue to shrink toward the molecular scale, self-assembly techniques could be used to enhance lithographic methods."
According to Chen, nanotechnology will aid conventional semiconductor processing, "potentially enabling continued device miniaturization and chip performance improvements." He says IBM researchers are using a "molecular self- assembly technique that is compatible with existing chip-making tools, making it attractive for applications in future microelectronics technologies, because it avoids the high cost of tooling changes and the risks associated with major process changes."
The self-assembly technique leverages the tendency of certain types of polymer molecules to organize themselves. Device processing, including self-assembly, is performed on 200 millimeter diameter silicon wafers using methods fully compatible with existing chip-making tools.
"The polymer molecules pattern critical device features that are smaller, denser, more precise, and more uniform than can be achieved using conventional methods like lithography," claims Chen. "The use of techniques such as self-assembly could ultimately lead to more powerful electronic devices, such as microprocessors used in the growing array of computer systems, communications devices and consumer electronics." Chen believes self-assembly techniques could be used in pilot phases 3 to 5 years from now.
Scientists at the Technion-Israel Institute of Technology (Haifa, Israel) recently harnessed the power of DNA to create a self-assembling nanoscale transistor. To get the transistors to self-assemble, a team of scientists led by Erez Braun attached a carbon nanotube onto a specific site on a DNA strand, and then made metal nanowires out of DNA molecules at each end of the nanotube. The device is a transistor that can be switched on and off by applying voltage to it. Out of 45 nanoscale devices created in three batches, almost a third emerged as self-assembled transistors. The carbon nanotubes used in the experiment are only 1 nanometer across.
"Though transistors made from carbon nanotubes have already been built, those required labor-intensive fabrication," says Braun. "The goal is to have these nanocircuits self-assemble, enabling large-scale manufacturing of nanoscale electronics. DNA is a natural place to look for a tool to create these circuits."
While this research demonstrates the feasibility of harnessing biology as a framework to construct electronics, Braun says "creating working electronics from self-assembling carbon nanotube transistors is still in the future."