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

O

OO

O OO O OO OO

O

S

O

S

O

S

O

S

O

S

O

S

O

S

O

S

PO

O

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.