What if we could assemble the basic ingredients of life the way nature does it, atom by atom and molecule by molecule?

“What I want to talk about is the problem of manipulating and controlling things on a small scale.” “Why cannot we write the entire 24 volumes of the Encyclopedia Brittanica on the head of a pin?” Feynman’s Talk, 1959, Caltech

head of a pin = 1/16 inches across × 25,000 = All the pages of the Encyclopedia Brittanica resolving power of a human eye 25,000 ÷ = 80 Angstroms (32 atoms in ordinary metal) 1/120 inch= diameter of a dot in the Encyclopedia

Feynman’s Talk, 1959, Caltech “What are the limitations as to how small a thing has to be before you can no longer mold it? How many times when you are working on something frustratingly tiny like your wife's wrist watch, have you said to yourself, ``If I could only train an ant to do this!'' What I would like to suggest is the possibility of training an ant to train a mite to do this”

Feynman’s Talk, 1959, Caltech “A friend of mine (Albert R. Hibbs) suggests a very interesting possibility for relatively small machines. He says that, although it is a very wild idea, it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and ``looks'' around. It finds out which valve is the faulty one and takes a little knife and slices it out.”

Electron-Beam Fabrication Molecular Beam Epitaxy Nanoimprint Lithography Spin Electronics Microelectromechanical Systems (MEMS)

Nano-Technology first used by N.Taniguchi (1974) Nanotechnology became popularized after K.E. Drexler’s book “Engines of Creation” in 1986.

What does Nanotechnology mean? “Nano” derives from the greek word for dwarf. It represents a billionth of a unit. 1nm = billionth of a meter = m

How small is a nanometer?

Some nanotechnology isn’t nano Nanotechnology, in some cases is not technology Nanotechnology is a new word but not an entirely new field. Nanotechonology: Real or just a buzz word?

Nano-sized carbon particles used in tires for about 100 years Vaccines, which often consist of one or more proteins with nanoscale dimensions Chemical catalysts, such as those turning cheap graphite into synthetic diamond. Photosynthesis (natural nanotechnology) Why not an entire new field?

Photosynthesis

What is special about Nanotechnology? Broad Interdisciplinary field Borderland between the atoms and the macroworld Human control at the finest scale

Nanotechnology: Is it fiction?

From Fiction to Reality: Skeptical Questions Can macroscopic objects be built from molecular scale processes? Are molecular objects stable? What about quantum effects? What about Brownian effects? What about high-energy radiation? What about friction and wear?

Nanotechnology does not violate any physical law.

Approaches to Nanotechnology Top-Down Approach Bottom-Up Approach

Top-Down Approach 1/4 Machine Shop Reduced-Scaled Machine Shop

MicroElectro-Mechanical Systems (MEMS)

Microcar by Nippondenso Co. Body: 4 mm long, 1.8 mm wide and 1.8 mm high Tires: 0.7 mm diameter, 0.17 mm wide Licence Plate: 10 micron thick

Top-Down Nanofabrication

Electron Beam Lithography Pattern written in a polymer film with a beam of electrons No blurring of features Very expensive and time-consuming X-ray Lithography Wavelength = nm, no blurring Conventional lenses do not focus X-rays Radiation damage of materials

Top-Down Nanofabrication

Bottom-Up Nanofabrication Supramolecular and molecular chemistry Scanning probes Biotechnology

Supramolecular Chemistry (Chemistry of non-covalent bonds) Self-Assembly demands: Well-defined adhesion between molecules Shape and size complementarity Large contact areas Strong overall binding

Advantages of Self-Assembly It carries by itself the most difficult steps in nanofabrication, i.e., the smallest steps Can incorporate biological structures directly as components in the final systems. Because target structures are thermodynamically stable, it produces structures that are relatively defect-free and self-healing.

Self-Assembly Carbon Nanotubes

Growth of C nanotubes CVD Synthesis

Self-Assembly Carbon Nanotubes

Structure of C Nanotubes Single Walled Nanotube Multi Walled Nanotube

Gears of C Nanotubes 70 GHz

Gears of C Nanotubes >150 GHz

Rack/Pinion C Nanotubes

Quantum Dots

Bottom-Up Nanofabrication Supramolecular and molecular chemistry Scanning probes Biotechnology

Scanning Probes

Manipulation of Atoms by SP

Atomic Writing by SP

Bottom-Up Nanofabrication Supramolecular and molecular chemistry Scanning probes Biotechnology

Drexler wrote: “The ability to design protein molecules will open a path to the fabrication of devices to complex atomic specfications”

Biotechnology Biological Molecular Machine: Ribosome 1 large RNA 1 small RNA 33 proteins 1 RNA 21 proteins

Ribosome as an assembler

Abalone

Abalone Shell: Self Assembly

Applications Nanodevices Nanoelectronics Nanomedicine

Nanodevices Single-Electron Transistor

Challenges for Nanodevices Communication between the macroworld and the nanoworld. Surfaces (high surface/volume ratios)

Nanoelectronics 1 st level of organization: transistors 2 nd level of organization: interconnects

Molecular Transistors

C Nanotube Interconnects Wire interconnect delays account for half of chip signal delays Copper interconnects being used for 130nm devices Microelectronic devices being scaled down from 130nm to 50nm generation Copper interconnects not suitable for 50nm devices

C Nanotube Interconnects First level interconnect

C Nanotube Interconnects Single wall nanotube  ~ 1.4 nm J c = 10 9 A/cm 2  ts ~ 30GPa K ~ 2000W/mK

DNA Computing

Nanomedicine Magnetic Nanoparticles N S

Nanomedicine

Nanotechnology: A Look to the Future Fiscal Year Europe Japan USA Others Total Estimated government sponsored R&D in $millions-year

Nanotechnology R&D at the Department of Defense (Funding:$140 M) Chem-bio warfare defense: sensors with improved detection sensitivity and selectivity, decontamination. Protective Armors for the warrior : Strong, light-weight bullets-stopping armor Reduction in weight of warfighting equipment: Miniaturization of sensors,computers, comm devices, and power supplies. High performance platforms and weapons: Greater stealth, higher strength light-weight materials and structures. Energy and Energetic Materials: Energetic nano-particles for fast release explosives and slow release propellants. Uninhabited vehicles: Miniaturization to reduce payload.

Nanotechnology R&D at the Department of Energy (Funding:$100 M) Fossil energy: materials performing under extreme temperatures and pressures, nanostructured catalysts for optimal petroleum refining. Energy efficiency : High-performance magnets, nanofluids, smart Materials, strong, tough, ductile materials. Renewable energy: Energy storage systems, nanostructured materials for hydrogen storage. Nuclear Energy: Radiation tolerant materials, nanostructures that lower waste disposal costs.

Nanotechnology R&D at NASA (Funding:$46 M) Nanostructured Materials: High strength/mass ratio, smart materials, Nanoelectronics: Space qualified data storage, self-healing systems for extended missions. Sensors: Nanodevices, NEMS flight system. Nanoscience: Self-assembly and processing in space, space-induced health effects.

Nanotechnology R&D at NIH (Funding:$40 M) Detection of Diseases Implants to replace worn or damaged body parts. Delivery of therapeutics Nanoimaging Cell Biology Nano-motors Cellular implants