1. Introduction to Nanotechnology
July 23, 2007
bnl
manchester

2. Some things we will discuss:
Introduction to Nanotechnology
July 23, 2007
Some things we will discuss:
How big are nanostructures
Scaling down to the nanoscale
How are nanostructures made?
Fabrication, synthesis, manufacturing
How do we see them?
Imaging and property characterization (measurement)
Why do we care?
Applications to science, technology and society

3. Why do we want to make things at the nanoscale?
To make better products: smaller, cheaper, faster and more effective. (Electronics, catalysts, water purification, solar cells, coatings, medical diagnostics & therapy, etc)
To introduce completely new physical phenomena to science and technology. (Quantum behavior and other effects.)

4. Nanotechnology
Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications.
1 nanometer = 1 x 10-9 m
= 1 billionth of a meter
nano.gov

5. How small are nanostructures?
Single Hair
Width = 0.1 mm
= 100 micrometers
= 100,000 nanometers !
1 nanometer = one billionth (10-9) meter

6. Smaller still
DNA
3 nanometers
6,000 nanometers
Hair
Red blood cell .

7. Down to the Nanoscale

8. From DOE

9. A Few Nanostructures Made at UMass
100 nm dots
70 nm nanowires
200 nm rings
150 nm holes
18 nm pores
12 nm pores
14 nm dots
13 nm rings
25 nm honeycomb
14 nm nanowires

10. "Nano" Nanoscale - at the 1-100 nm scale, roughly
Nanostructure - an object that has nanoscale features
Nanoscience - the behavior and properties of nanostructures
Nanotechnology - the techniques for making and characterizing nanostructures and putting them to use
Nanomanufacturing - methods for producing nanostructures in reliable and commercially viable ways

11. Nanotechnology R&D is interdisciplinary and impacts many industries
Physics
Chemistry
Biology
Materials Science
Polymer Science
Electrical Engineering
Chemical Engineering
Mechanical Engineering
Medicine
And others
Electronics
Materials
Health/Biotech
Chemical
Environmental
Energy
Aerospace
Automotive
Security
Forest products
And others

12. An application example: Nanoelectronics

13. Making Small Smaller An Example: Electronics-Microprocessors
microscale
nanoscale
macroscale
ibm.com

14. Electronics Keep On Getting Better
Moore's "Law": Number of Transistors per Microprocessor Chip
intel.com

15. Since the 1980's electronics has been a leading commercial driver for nanotechnology R&D, but other areas (materials, biotech, energy, etc) are of significant and growing importance.
Some have been around for a very long time:
Stained glass windows (Venice, Italy) - gold nanoparticles
Photographic film - silver nanoparticles
Tires - carbon black nanoparticles
Catalytic converters - nanoscale coatings of platinum and palladium

16. nano.gov
"Biggest science initiative since the Apollo program"

17. National Nanotechnology Initiative
Research Areas (2007 Federal Budget)
Fundamental Nanoscale Phenomena and Processes
Nanomaterials
Nanoscale Devices and Systems
Instrumentation Research, Metrology and Standards for Nanotechnology
Nanomanufacturing
Major Research Facilities and Instrumentation Acquisition
Societal Dimensions

18. A National Science Foundation Nano Center
nanomanufacturing.org
A National Science Foundation Nano Center

19. Nanostructures

20. Nanostructures nanofilm, macroscale (3D) object or nanolayer (2D)
height
depth
width
nanoparticle,
nanodot,
quantum dot (0D)
nanowire,
nanorod, or
nanocylinder (1D)

21. Making Nanostructures: Nanofabrication
Top down versus bottom up methods
Lithography
Deposition
Etching
Machining
Chemical
Self-Assembly

22. Nanofilms (making an object thin)

23. An example of a FILM A monolayer NANOFILM (single layer of molecules)
~1 nm thick
Langmuir film
This is an example of SELF-ASSEMBLY

24. CHALLENGE: How thick was the film of oil?
... the Oil tho' not more than a Tea Spoonful ...
... perhaps half an Acre
CHALLENGE: How thick was the film of oil?
Volume = (Area)(Thickness)
V = A t
t = V/A =
2 cm3
20,000,000 cm2
V = 1 teaspoonful
A = 0.5 acre
~ 2 cm3
~ 2,000 m2
= cm
= 1 x 10-7 cm
= 1 x 10-9 m
= 1 nanometer (nm)
20,000,000 cm2

25. Langmuir Film of an amphiphilic molecule water hydrophobic end
e.g., oleic acid
pressure
of an amphiphilic
molecule
monolayer film
water
hydrophilic end

26. Langmuir-Blodgett Film
Must control movable
barrier to keep constant
pressure
multiple dips -
multiple layers

27. Another film method, Thermal Evaporation
sample
QCM
Vaporization or sublimation of a heated material onto a substrate in a vacuum chamber
film
vapor
Au, Cr, Al, Ag, Cu, SiO, others
Pressure must be held low
to prevent contamination!
vacuum
~10-7 torr
source
There are many other
thin film manufacturing
techniques
resistive, e-beam, rf or laser
heat source
vacuum
pump

28. Lithography (controlling width and depth)

29. Mark Tuominen Mark Tuominen
Lithography
Mark
Tuominen
Mark
Tuominen
(Using a stencil or mask)

30. Making a nanoscopic mask
Example: Electron-Beam Lithography
Electron Beam
Polymer film
Silicon crystal
Nanoscopic Mask !

31. Lithography Patterned Several IBM Times Copper Wiring On a Computer
Chip

32. Self-Assembled Nanostructures

33. Self
Assembly

34. Tobacco Mosaic Virus
wisc.edu
nih.gov

35. Gecko feet

36. Diatoms
sinancanan.net
priweb.org

37. Abalone

38. The Cell and Its Hierarchy
ebi.ac.uk

39. Self assembly at all scales? Whitesides et al. Science 295,
2418 (2002);

40. NANOFABRICATION BY SELF ASSEMBLY
One Example: Diblock Copolymers
Block “B”
Block “A” PS
PMMA
~10 nm
Scale set by molecular size
Ordered Phases
10% A
30% A
50% A
70% A
90% A

41. Versatile, self-assembling, nanoscale lithographic system
CORE CONCEPT
FOR NANOFABRICATION
Deposition
Template
Etching
Mask
Nanoporous
Membrane
(physical or
electrochemical)
Remove polymer
block within cylinders
(expose and develop)
Versatile, self-assembling, nanoscale lithographic system

42. USING DIBLOCK COPOLYMER TEMPLATES
NANOFABRICATION
USING DIBLOCK COPOLYMER TEMPLATES
template
dots
cylinders
rings
holes

43. Measuring Nanostructures

44. How do we see nanostructures?
• A light microscope? Helpful, but cannot resolve below 1000 nm
• An electron microscope? Has a long history of usefulness at the nanoscale
• A scanning probe microscope? A newer tool that has advanced imaging

45. Television Set prelim. TV screen eye Light ! electron beam electron
source

46. Scanning Electron Microscope
Beam
DETECTOR
SAMPLE

47. (Atomic Force Microscope) "Optical Lever"
laser pointer
To determine amplification factor, use the concept of similar triangles

48. Scanning probe microscope
Laser Beam
Vibrating Cantilever
PS/PEO
AFM image µm
(large )
Surface
AFM, STM, MFM, others

49. Quicktime AFM Cantilever Chip AFM Instrument Head Laser Beam Path
Cantilever Deflection

50. Scanning probe microscope
Laser Beam
Vibrating Cantilever
PS/PEO
AFM image µm
(large )
Surface
AFM, STM, MFM, others

51. STM
Image of Nickel Atoms

52. Pushing Atoms Around
STM

54. "Optical Lever" x2 x1 y1 y2
For example, if the laser pointer is 2" long, and the wall is 17' (204") away,
Motion amplified by 100 times!

55. "Optical Lever" for Profilometry
laser .
cantilever

56. "Optical Lever" for Profilometry
Long light path and a short cantilever gives large amplification
laser .
cantilever