Post on 30-Dec-2015
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Overview andIntroduction to Nanotechnology:
What, Why and How
Overview andIntroduction to Nanotechnology:
What, Why and How
Mark Tuominen Professor of Physics
Jonathan Rothstein Professor of Mechanical Eng.
NSF Center for Hierarchical Manufacturing
Research Education Outreach
A Center on Nanomanufacturing at UMass
"NSEC"
Supported by the National Science Foundation
Next Generation Science Standards (NGSS):
Three Pillars
• Disciplinary Core Ideas
• Science and Engineering Practices
• Crosscutting Concepts
STEM Careers
- Currently, there are 14 million people unemployed people in the U.S. and 3 million unfilled STEM jobs -- There is a STEM skills gap!
U.S. News & World Report STEM Solutions 2012 Leadership Summit: http://usnewsstemsolutions.com/ June 27-29, 2012
STEM Skills- Mathematical literacy- Ability to apply STEM knowledge to real-
world situations- There are many technician-level jobs- Need many STEM-skilled people for
sophisticated jobs in manufacturing- Typically, students are not aware of the
types of jobs a STEM education can lead to
Science DOI: 10.1126/science.caredit.a1200076 Michael Price July 6, 2012
NanotechnologyThe biggest science initiative
since the Apollo program
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 billionth of a meter= 1 x 10-9 m
nano.gov
How small are nanostructures?
Single Hair
Width = 0.1 mm
= 100 micrometers
= 100,000 nanometers !
Smaller still
Hair
.
DNA
3 nanometers
6,000 nanometers
100,000 nanometers
10 nm objectsmade by guided
self-assembly
Red blood cells(~7-8 m)
Things NaturalThings Natural Things ManmadeThings Manmade
Fly ash~ 10-20m
Head of a pin1-2 mm
Quantum corral of 48 iron atoms on copper surfacepositioned one at a time with an STM tip
Corral diameter 14 nm
Human hair~ 60-120m wide
Ant~ 5 mm
Dust mite
200 m
ATP synthase
~10 nm diameterNanotube electrode
Carbon nanotube~1.3 nm diameter
O O
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O OO O OO OO
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The Challenge
Fabricate and combine nanoscale building blocks to make useful devices, e.g., a photosynthetic reaction center with integral semiconductor storage.
Mic
row
orl
d
0.1 nm
1 nanometer (nm)
0.01 m10 nm
0.1 m100 nm
1 micrometer (m)
0.01 mm10 m
0.1 mm100 m
1 millimeter (mm)
1 cm10 mm
10-2 m
10-3 m
10-4 m
10-5 m
10-6 m
10-7 m
10-8 m
10-9 m
10-10 m
Visi
ble
Nan
ow
orl
d
1,000 nanometers = In
frar
edU
ltrav
iole
tM
icro
wav
eSo
ft x-
ray
1,000,000 nanometers =
Zone plate x-ray “lens”Outer ring spacing ~35 nm
Office of Basic Energy SciencesOffice of Science, U.S. DOE
Version 05-26-06, pmd
The Scale of Things – Nanometers and MoreThe Scale of Things – Nanometers and More
MicroElectroMechanical (MEMS) devices10 -100 m wide
Red blood cellsPollen grain
Carbon buckyball
~1 nm diameter
Self-assembled,Nature-inspired structureMany 10s of nm
Atoms of siliconspacing 0.078 nm
DNA~2-1/2 nm diameter
Applications of Nanotechnology
10 GB2001
20 GB2002
40 GB2004
80 GB2006
160 GB2007
First, One Example: iPod Data Storage Capacity
Hard driveMagnetic data storage
Uses nanotechnology!
Hard Disk Drives - a home for bits
Hitachi
Magnetic Data StorageA computer hard drive stores your data magnetically
Disk
N S
direction of disk motion
“ Write”Head
0 0 1 0 1 0 0 1 1 0 _ _
“ Bits” ofinformation
NS
“ Read”Head
Signalcurrent
magnets
Improving Magnetic Data Storage Technology
• The UMass Amherst Center for Hierarchical Manufacturing is working to improve this technology
Granular Media
PerpendicularWrite Head
Soft Magnetic UnderLayer (SUL)
coil
Y. Sonobe, et al., JMMM (2006)
1 bit
• CHM Goal: Make "perfect" mediausing self-assembled nano-templates• Also, making new designs for storage
Since the 1980's electronics has been a leading commercial driver for nanotechnology R&D, but other areas (materials, biotech, energy, and others) are of significant and growing importance.
Some applications of nanotechnology has been around for a very long time already:• Stained glass windows (Venice, Italy) - gold nanoparticles• Photographic film - silver nanoparticles• Tires - carbon black nanoparticles• Catalytic converters - nanoscale coatings of platinum and palladium
Applications of Nanotechnology
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, and more -- a sustainable future!)
• To discover completely new physical phenomena to science and technology. (Quantum behavior and other effects.)
The National Nanotechnology Initiative
nano.gov - the website of the NNI
Types of Nanostructuresand How They Are Made
"Nanostructures"
Nano-objects Nanostructured Materials
nanoscale outer dimensions
nanoscale internal structure
Nanoscale Devices and SystemsIntegrated nano-objects and materials
"nanoparticle""nanorod"
"nanofilm"
"nanotube"and more
Making Nanostructures: Nanomanufacturing
"Top down" versus "bottom up" methods
•Lithography•Deposition•Etching•Machining
•Chemical•Self-Assembly
Some nanomaterials are just alternate arrangements of well-
known materials
Carbon materials
2010 Nobel Prize!
Nanofilms
Gold-coated plastic for insulation purposes
"Low-E" windows: a thin metal layer on glass: blocks UV and IR light
Nanofilm on plasticNanofilm on glass
A nanofilm method:Thermal Evaporation
Vaporization or sublimation of a heated material onto a substrate in a vacuum chamber
vacuum~10-7 torr
sample
source
film
vacuumpump
QCM
vapor
heating source
Pressure is held low to prevent contamination!
Au, Cr, Al, Ag, Cu, SiO, others
There are many otherthin film manufacturingtechniques
Patterning: Photolithography
substrate
process recipe
spin on resist
resist
expose
mask (reticle)
develop
deposit
apply spin bake
spin coating
exposed unexposed
"scission"
liftoff
etch
narrow line
narrow trench
Patterning: Imprint Lithography
Mold Template
Polymer or Prepolymer
Substrate
ImprintPressure
Heat or Cure
Release
• Thermal Imprint Lithography
– Emboss pattern into thermoplastic or thermoset with heating
• UV-Assisted Imprint Lithography
– Curing polymer while in contact with hard, transparent mold
Limits of Lithography
• Complex devices need to be patterned several times
Takes time and is expensive
• Limited by wavelength of light
Deep UV ~ 30nm features
• Can use electrons instead
1nm features possible
MUCH slower than optical IBM - Copper Wiring
On a Computer Chip
Self Assembly
An Early Nanotechnologist?
Excerpt from Letter of Benjamin Franklin to William Brownrigg (Nov. 7, 1773)
...At length being at Clapham, where there is, on the Common, a large Pond ... I fetched out a Cruet of Oil, and dropt a little of it on the Water. I saw it spread itself with surprising Swiftness upon the Surface ... the Oil tho' not more than a Tea Spoonful ... which spread amazingly, and extended itself gradually till it reached the Lee Side, making all that Quarter of the Pond, perhaps half an Acre, as smooth as a Looking Glass....
A nanofilm!
"Synthesis and Characterization of Nearly Monodisperse Semiconductor Nanocrystallites," C. Murray, D. Norris, and M. Bawendi, J. Am. Chem. Soc. 115, 8706 (1993)
"Quantum Dots" by Chemical Synthesis
(reverse-micelle method)
Color is determined by particle size!
a
Interaction with Light
"Artificial atom"
E = hf
420 THz 750 THz
Many applications: solar cells, biomarkers, lighting, and more!
Immiscibility and phase separation:Driven by intermolecular interactions
Olive oil
Balsamicvinegar
Polymer mixture
Thermodynamically driven
SELF ASSEMBLY with DIBLOCK COPOLYMERS
Block “A ” Block “B”
10% A 30% A 50% A 70% A 90% A
~10 nm
Ordered Phases
PMMA PS
Scale set by molecular size
nanoporous template
Nanomagnets in a Self-Assembled Polymer Mask
1x1012 magnets/in2
Data Storage......and More
Conducting Nanowires from Bacteria
Bacterium Cell: GeobacterSulfurreducens
Bacterial “Nanowires”
Nature Nanotechnology 6, 573-579 (2011)
A Few More Applications of Nanotechnology
Solar Cells
Konarka
Benefit: Sun is an unlimited source of electronic energy.
Electric Solar Cellsp-n junction interface
cross-sectional view
n-type silicon
p-type silicon
+
-
Sunlight
Voltage “load”
CurrentThe electric power produced is proportional to the area of the solar cell
- - - -- - - - + + + ++ + + + 0.5 Volt
Nanostructured Solar Cells
+
-
Sunlight
Voltage “load”
CurrentMore interface area - More power!
Nanomedicine: Tumor-targeted Cancer Therapy
C&EN News June 4, 2012
C&EN News June 4, 2012
Nanospectra Biosciences
Nanotechnology is an example ofInterdisciplinary Collaboration at work
People from diverse fields working together -- more rapidly solving important problems in our
society• Physics• Chemistry• Biology• Materials Science• Polymer Science• Electrical Engineering• Chemical Engineering• Mechanical Engineering• Medicine• And others
• Electronics• Materials• Health/Biotech• Chemical• Environmental• Energy• Food• Aerospace• Automotive• Security• Forest products
A Message for Students
- Nanotechnology is changing practically every part of our lives. It is a field for people who want to solve technological challenges facing societies across the world.
- There are well-paying, interesting jobs – technician, engineer, scientist, manufacturing, sales, and others.