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

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

4. Feynman’s Talk, 1959, Caltech “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?”

5. × = 25,000 head of a pin = 1/16 inches across All the pages of the Encyclopedia Brittanica 1/120 inch= diameter of a dot inthe Encyclopedia 80 Angstroms (32 atoms in ordinary metal) ÷ = 25,000 resolving power of a human eye

6. 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”

7. 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.”

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

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

10. What does Nanotechnology mean? • “Nano” derives from the greek word for dwarf. • It represents a billionth of a unit. • 1nm = billionth of a meter = 10-9 m

11. How small is a nanometer?

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

13. Why not an entire new field? • 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)

14. Photosynthesis

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

16. Nanotechnology: Is it fiction?

17. 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?

18. Nanotechnology does not violate any physical law.

19. Approaches to Nanotechnology • Top-Down Approach • Bottom-Up Approach

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

21. MicroElectro-Mechanical Systems (MEMS)

22. MicroElectro-Mechanical Systems (MEMS)

23. 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

24. Top-Down Nanofabrication

25. 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 = 0.1-10 nm, no blurring • Conventional lenses do not focus X-rays • Radiation damage of materials

26. Top-Down Nanofabrication

27. Bottom-Up Nanofabrication • Supramolecular and molecular chemistry • Scanning probes • Biotechnology

28. 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

29. 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.

30. Self-Assembly Carbon Nanotubes

31. Growth of C nanotubes CVD Synthesis

32. Self-Assembly Carbon Nanotubes

33. Structure of C Nanotubes Single Walled Nanotube Multi Walled Nanotube

34. Gears of C Nanotubes 70 GHz

35. Gears of C Nanotubes >150 GHz

36. Rack/Pinion C Nanotubes

37. Quantum Dots

38. Bottom-Up Nanofabrication • Supramolecular and molecular chemistry • Scanning probes • Biotechnology

39. Scanning Probes

40. Manipulation of Atoms by SP

41. Atomic Writing by SP

42. Bottom-Up Nanofabrication • Supramolecular and molecular chemistry • Scanning probes • Biotechnology

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

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

45. Ribosome as an assembler

46. Abalone

47. Abalone Shell: Self Assembly

48. Applications • Nanodevices • Nanoelectronics • Nanomedicine

49. Nanodevices Single-Electron Transistor

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