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Nanotechnology Is BIG at NISTEver smaller and ever faster. The pursuit of nanotechnologychips, sensors, pumps, gears, lasers, novel materials, and an unending assortment of other useful things with features on the scale between one-billionth of a meter (about 10 hydrogen atoms across) and 100-billionths of a meteris driving science and engineering to extremes. Consider work under way at the National Institute of Standards and Technology (NIST), where research truly is pushing the limits of technology. Here, scientists and engineers are building atom and electron counters, single-photon turnstiles, ultracold ion and atom traps, and lasers that generate uniform pulses of light that last only a few trillionths of a second. For NIST, the quest to design, manipulate, manufacture, and assemble at the molecular and atomic levels translates into a full agenda of demanding measurement jobs and related tasks. Already, more than 1,700 companies in 34 nations reportedly are pursuing the commercial promise of nanotechnology. Mastery of the almost infinitesimally small, however, will require an underlying technical foundation. Just like gage blocks (standardized sets of hardened steel blocks of accurately determined thicknesses) and other widely adopted measurement tools that enabled the rise of mass production and interchangeable parts, exceedingly accurate measurement tools and other underpinning generic technologies will be essential to realizing the anticipated bounty of nanotechnology products and services. NIST role Researchers in NISTs seven major laboratories are developing measurements, standards, and data crucial to private industrys development of products for a nanotechnology market that could reach $1 trillion during the next decade. NISTs work also aids federal agencies efforts to exploit nanotechnology to further their missions, such as national security and environmental protection. These technical contributions are in addition to NISTs funding support for U.S. industrys nanotechnology development work.
NIST and the National Nanotechnology Initiative As the nations premier measurement laboratory, NIST is a key contributor to the National Nanotechnology Initiative (NNI), a long-term federal effort to speed the advance of the emerging fields of nanoscale science, engineering, and technology. In 2002, NIST funding for nanotechnology-related projects in the NIST laboratories totaled almost $40 million. Development of instrumentation and standardsessential building blocks of a nanotechnology infrastructureis one of the NNIs top priorities. NIST leads efforts to address two of the NNIs Grand Challenges: one on instrumentation and metrology (measurement science) and, with the National Science Foundation, one on manufacturing processes. It also contributes significantly to work on materials, electronics and optoelectronics, and elements of other initiative grand challenges. In all these areas, measurement advances are key to achieving the understanding needed to harness nanoscale properties and quantum phenomena. Likewise, new measurement tools enable the process and control capabilities necessary for cost-effective production of high-quality nanotechnology products. For fiscal year 2004, the President has requested a funding increase of $5.2 million to further NISTs nanotechnology efforts. The President also has proposed an additional $3 million to accelerate and intensify NISTs globally recognized work in quantum information science. This work aims to exploit the peculiar quantum behavior of molecules, atoms, and subatomic particles and to pave the way for enormously powerful quantum computers and perfectly secure communications systems. Even before nanotechnology became a buzzword, NIST scientists and engineers were moving to address the inevitable need to measure and control processes at molecular levels. The scale and pace of these efforts have grown in response to increasing industrial and scientific demand. As a result, NISTs penchant for precision and accuracy must rise to new levels. After all, when working in the nanoscale realm, pinpoint accuracy only gets you in the general neighborhood, a hairs breadth is a cavernous space, and a split second might as well be an eon. United by a focus on measurements, data, and standards, nanotechnology efforts in the NIST laboratories reach well beyond current capabilities, all the way into the fuzzy, probabilistic realm of quantum mechanics. Laboratory projects cut across five important areas, as explained below. Fundamental science and basic measurement capabilities Although every industry has unique priorities, some basic technology needs transcend business sectors and fields of technology. In support of many industries aiming for nanotechnology products and services, NIST is helping to advance fundamental understanding of the properties and performance of matter from the bottom upat the level of atoms and molecules. The agency also is responding to this and other shared needs by developing measurement references that are based on unchanging natural phenomena: quantum processes and fundamental constants. This work will lead to extremely accurate universal measurement standards that could be realized anywherewithout the aid of material artifacts. Indeed, many industriesestablished and those in the makingwill require higher-resolution measurements of length, time, force, mass, and chemical composition that correspond to the molecular and atomic scales of nanotechnology. Complementary efforts aim to develop and harden capabilities for precisely manipulating and assembling the basic building blocks of nanotechnology products. Sample highlights For example, NIST scientists and engineers have:
Characterization of nanostructured materials Emerging capabilities to combine disparate atoms and molecules, to tinker with molecular structure, and to maximize properties by exploiting peculiar quantum behaviors have created a smorgasbord of tantalizing opportunities. Nanoscale alterations and additions make it possible to create tailor-made materials optimized for specific usesfrom new insulators for integrated circuits to superior stealth coatings for military aircraft to superior-performing, biologically compatible materials for implanted biomedical devices. Up to 100 times stronger than steel, carbon nanotubes are an area of especially intense interest. Discovered in the early 1990s, the nanometer-sized cylinders of carbon already are being eyed for electronic, automotive, aerospace, and a variety of other applications. To speed progress, NIST is developing new nanometer-resolution probes of the properties and three-dimensional atomic arrangements of nano-structured materials. NIST also is building a collection of high-speed screening methods that permit designers to evaluate the strengths and weaknesses of their creations. Sample highlights Institute scientists recently:
Nanoscale electronics, optoelectronics, and magnetics Demand for faster, more powerful information technology will not abate. Nor will the unrelenting space crunch in data storage ease any time soon. Down the road, when current manufacturing methods are extended to their limit, nanotechnologyin the forms of molecular electronics and spintronic devices that manipulate the spins of electronscould provide the answer to both challenges. Besides providing chipmakers and their suppliers with essential tools to meet todays severe process-control and quality requirements, NIST also is looking several generations beyond current integrated circuit technology. For example, a collection of molecular electronics projects has the overall aim of developing the measurement science base that will enable industry to, quite literally, make a quantum leap in the design and fabrication of electronic devices. NIST measurement support is credited with helping the U.S. data storage industry (.pdf; download Acrobat Reader) develop more sensitive read heads that capitalize on the giant magnetoresistance (GMR) effect, discovered in the late 1980s. Exploited in commercial technology less than a decade later, the quantum phenomenon enabled the industry to continue its trend of increasing data storage capacity by more than 40 percent annually. Ongoing NIST projects aim to extend measurement and imaging capabilities in support of industry efforts to develop more powerful and more versatile magnetic devices, such as magnetic random access memories, which retain data even when power is interrupted, and tunable spintronic microwave devices that would increase storage capacity vastly. The NIST laboratories also help to further industry efforts to design and manufacture affordable integrated circuits that combine, on a single chip, devices that control electrons with those that manipulate light, such as lasers, filters, amplifiers, and switches. Today, photonic and electronic devices are packaged as discrete components, linked by optical fiber. Although these hybrid packages are the lifeblood of advanced telecommunication technologies, nanotechnology techniques will enable integrated optoelectronic circuits that deliver higher performance and new capabilities at a lower cost. Since the mid-1970s, NIST has been providing measurement and related technical support to the optical communications industry. Today, work spans from characterizing the properties and performance of tailor-made photonic crystals to exploring methods for patterning periodic arrays of quantum dots, artificial atoms created by isolating and confining electrons in a small space. Already used in lasers, quantum dots are at the center of much innovative activity in electronics, optoelectronics, and biotechnology as well as other areas. A recent survey found 230 U.S. patents covering quantum dots and their applications. Sample highlights Recent developments and accomplishments include:
Nanochemistry and nanobiotechnology At its most basic level, nanotechnology is a matter of breaking and making chemical bonds. The expanding ability to form novel chemical relationships can result in dramatic transformations in the properties and performance of materials. Many of the new strategies and methods for organizing and linking atoms and molecules are borrowed directly from nature. Consider, for example, cellular methods of self-assemblysometimes called programmed chemistrythat result in proteins and organelles, the machinery of cells. NIST studies in the early 1990s helped to establish the feasibility of self-assembly as a means of chemical synthesis. Obtained with a unique, custom-built microscope, high-resolution images of self-assembled monolayers, a class of ultrathin organic films eyed for many applications, revealed important structural details of the films. The results also helped to explain the principles and forces that govern the process of self-assembly. Current nanochemistry efforts range from refining NIST-developed methods for fabricating and miniaturizing components of plastic lab-on-a-chip devices to pushing beyond the limits of chemical imaging technologies. With a battery of tools now under development, NIST researchers aim for rapid detection and identification of single atoms and molecules in an area measuring one square micrometer, a huge space in the nano world. In the long run, health care, in general, and biotechnology, in particular, may realize the largest dividends from advances in nanotechnology. Anticipated applications range from biosensors and targeted drug-release systems to tissue repair and generation. The number and types of measurements that must be made during the design, fabrication, testing, and approval of such technologies are large. Some of these measurement needs have just begun to receive attention. Already a supplier of measurement references for DNA analyses, cholesterol tests, and a variety of other clinical tests, NIST is expanding the scope of projects devoted to helping others to innovate and to introduce nanotechnology applications that are safe and deliver substantial benefit to health-care consumers and practitioners. A key focus area is tissue engineering, where the number of factors to be controlled or monitored is huge. For example, NIST researchers are developing genetically engineered smooth muscle cells that can help evaluate biomaterials for blood vessel stents. The cells emit fluorescent light whenever they are replicating. Ideally, these biomaterials should discourage cell replication, which tends to reclog the artery requiring the stent. By validating that the cells fluoresce consistently under controlled conditions, NIST hopes to provide a valuable tool for quickly testing which stent materials are least likely to reclog. Sample highlights Recent NIST accomplishments include:
Quantum computing and communications NIST has done pioneering work in laser cooling of atoms and ions, earning two of its researchers the Nobel Prize in Physics (in 1997 and 2001) and a third the 2000 International Quantum Communication Award. This work lays the foundation for quantum computing, which calls for the use of quantum bits, or qubits, instead of the familiar digital bits used in conventional computers. Quantum computers have the potential to store and process enormous amounts of information, immensely more than can be handled by todays computers. What are now intractable scientific and technical problems would become ripe for research and, ultimately, solution. Quantum computers could factor very large numbers, perform cryptography, and aid science in large-scale modeling projects such as first-principles simulation of materials properties. Quantum communications techniques offer greatly improved security of data communications by making covert eavesdropping physically impossible. Sample highlights Examples of NISTs recent contributions to the quest for quantum computing and communications technology are:
Specialized nanotechnology facilities and capabilities Nanotechnology is both the means to an endan enabler of accomplishments in a truly diverse mix of science and engineering fieldsand, perhaps, the end in and of itselfa revolution in industry that will deliver wave after wave of innovative products and services. Work under way at NIST illustrates nanotechnologys dual nature. Many projects are leveraging capabilities to manipulate molecules, atoms, and even subatomic particles with the aim of enhancing existing services for established industries, from increasing the accuracy calibrations to developing portable measurement references that customers can use on-site. Others are addressing measurement-related challenges confronting businesses and industries still in the making. Both sets of activities are carried out collaboratively, and both benefit from a diverse collection of facilities and equipment, some of it custom-designed and unique to NIST. Some examples follow. Advanced Measurement Laboratory (AML) In 2004, NIST scientists will begin moving into what will be the worlds premier all-purpose facility for measurement-related research. The 47,480-square-meter (511,070-square-foot), $235.2 million AML will give NIST and its partners in U.S. industry access to research and development capabilities not available anywhere else in the world. Stringent controls on particulate matter, temperature, vibration, and humidity will reduce environmental noise to unprecedented levels, eliminating obstacles to research and services in nanoscale science and engineering. The AML will consist of five sections: two single-floor measurement laboratory sections below ground with 151 modules (for improved vibration isolation and temperature control), two single-floor instrument laboratory sections above ground with 187 modules and one ultraclean room wing above ground. Specialty areas within the AML include 48 precision temperature control laboratories (constant temperatures within ±0.1 degree Celsius or ±0.01 degree Celsius depending on need) and 27 extremely low-vibration laboratories. NIST Center for Neutron Research (NCNR) A national user facility and one of the best of its kind in the world, the NCNR generates high-quality beams of neutrons, which are becoming increasingly indispensable research tools in fields ranging from biology to materials science, often in applications with high impact on future nanotechnology. Neutrons are non-destructive, highly penetrating probes, useful for studying the structure, properties, and dynamics of materials of many typesfrom proteins to nanocomposite coatings. Because they behave like tiny waves of energy, neutrons also make excellent rulers. Depending on neutron temperature, the length of the neutron ruler can be tuned over a range spanning from roughly the size of a single atom to the size of a molecule composed of hundreds or thousands of atoms. The major source of cold neutrons in the United States, the NCNR houses 28 experiment stations. Each year, these instruments support the research of more than 1,700 scientists and engineers from 250 universities, companies, and government laboratories. NIST Combinatorial Methods Center This collaborative research center is devoted to advanced state-of-the-art high-throughput methods that can accelerate development of new materials. Combinatorial methods and the supporting resources at the year-old center allow researchers to explore simultaneouslyor in rapid sequencecombinations of materials characteristics and formulations on a miniaturized scale. Such methods enable researchers to evaluate quickly how composition and processing influence a materials performance. With combinatorial tools, they can pinpoint optimal processing conditions, screen for novel properties, and build comprehensive data sets and models. The methods are well-suited to study polymer coatings and multilayers down to nanometer-scale thicknesses, such as used in microelectronic applications. Ongoing work focuses on designing and evaluating thin polymer films for enhanced nanomechanical, thermal, and UV (ultraviolet light) dependent properties. Another project focuses on approaches for screening polymers with clay, nanotube, and nanoparticle additives for improved fire resistance. The centerpiece of a new program to develop a solid understanding of how electrons behave in quantum-confined systems, including so-called spintronic devices, this new resource began its initial trial in late 2002. Features include a state-of-the art cryogenic scanning tunneling microscope (STM); a superconducting magnet system that can generate intense magnetic fields; a molecular beam epitaxy system for fabricating nanostructures from a variety of classes of materials; and a microscope for customized preparation of STM probes. The entire system can operate in an ultrahigh vacuum environment with automated transfer and placement of samples and STM probes. Additionally, this facility will test the concept of the autonomous assembly of nanostructures designed to realize magnetic and electronic properties stemming from quantum phenomena. Such structures will be assembled autonomously, atom by atom, under computer control. Molecular Measuring Machine (M3) This NIST-conceived two-dimensional coordinate measuring machine can measurewith nanometer-level accuracylocations, distances, and feature sizes over a 50-millimeter by 50-millimeter area, an enormous expanse in the nanotechnology world. M3 uses an STM with sub-nanometer resolution as its sensing probe and a high-precision interferometer (also with sub-nanometer resolution) to measure the probes position as it traverses a sample artifact. Magnetic Engineering Research Facility Established with the aim of advancing enabling technologies key to ultrahigh-density data storage, this laboratory is one of the worlds most elaborately instrumented facilities for preparing and evaluating magnetic thin films. It supports research ranging from the most basic to the industrially applied. Thin-film samples can be studied with the most modern surface, interface, and magnetic diagnostics at each step in the fabrication process. Properties that can be investigated include elemental composition, thickness, atomic structure, roughness, and magnetic and magnetoresistive properties. These capabilities allow researchers to establish the correlations between the film structure and properties and to use the resulting insights to control and improve the properties of device-related materials. Pulsed Inductive Microwave Magnetometer (PIMM) This unique NIST-developed instrumenta significant advance in technology for picosecond measurements of ultrafast magnetization switchingcan accelerate the search for new materials needed for next-generation high-speed recording heads. Using PIMM, materials scientists, in their quest for novel, highly magnetic, nanostructured materials to record data in extremely small bits (at sizes below 160 square nanometers per bit), now can assess quickly the composition and growth conditions that promote high-speed response, permitting the development of future magnetic memories that read and write data at sustained speeds in excess of 1 billion bits per second. With such data rates, one could store the informational content of the Encyclopedia Britannica in little more than one minute. The battery of property data gathered with the new, highly automated magnetometer rapidly yields a comprehensive assessment of a magnetic alloys dynamic behavior, which determines whether a candidate material has the potential to meet the industrys targets for increasing data storage performance. For more information on NISTs nanotechnology work, contact: Barbara Goldstein, (301) 975-2304; barbara.goldstein@nist.gov. Date
created: February 12, 2003
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