Nanomaterials and Nanoscience · Everything changes at the quantum scale Mechanical strength,...
Transcript of Nanomaterials and Nanoscience · Everything changes at the quantum scale Mechanical strength,...
1 µm
Philip G. Collins
Dept. of Physics and Astronomy
Nanomaterials and Nanoscience
• why go nano?
Atomic Resolution Microscopes
the AFM,STM,TEM,
and SEM
Conventional Properties
IBM Research, 1992
Copper at the Nanoscale
One Atom “Trapped” Electrons
1 nanometer = 1 nm
Everything changes at the quantum scale
Mechanical strength, toughness high strength, low weightcomposites
Chemical bonding, reactivity chemical and biologicalreceptors or sensors
Thermal insulators, conductors high temperature orhigh power applications
Electrical conductivity, ductility microelectronics
Optical absorption, reflectivity high bandwidth fibersor waveguides
Physical Property Uses
Al Si P ArCl
C
He
NeN FO
Cr Fe Co Ni CuTi
Pt Au
Nb Pd Ag
H
I Xe
Pb Bi
Ge AsGa KrBr83.80
131.29
4.0026
20.18014.007
39.94835.453
18.99815.99912.01
26.982 28.086 30.974
69.723 7 2.61 74.922 79.904
126.90
207.2 208.98
58.933 58.693 63.546
1.0079
47.867 51.996 55.845
92.906 106.42 107.87
195.08 196.97
PERIOD
GROUP
1
2
3
4
5
6
2
107
1817
98
36
54
16
13 14 15
28 29 31 32 33 35
5346 47
78 79 83
1
22 24 26 27
41
HY DROGEN
NIOBIUM
TIT ANIUM CHROMIUM COBA L TIRON
HELIUM
NEO NNIT ROGEN FL UORINEOXYGENCARBON
ARGONCHLORINEALUM INIUM SILICON P HOS PHORUS
KRYP T ONNICKEL COPPER G ALLIUM GERMANIUM ARSENIC B ROMINE
XENONIODINEPALLADIUM SIL V ER
P LA TINUM GOLD LEAD BISMUTH
11
13 14 15 16 17
181
54 6 8 9 10
NanoPeriodic Table – Under construction
Jim Heath, UCLA
© Foresight Institute
• what isnanotechnology?
tech·nol·o·gy n1. The application of science,
especially to industrial or commercial objectives
Nanoscience Nanofiction
© Vic Olliver
Nanorobots repairingred blood cells
Nanotechnology
© QuantumDot Corp.
Inside a fluorescentlylabeled cell
REPORTS
www.sciencemag.org SCIENCE VOL 291 16 MARCH 2001 2115
Colloidal Nanocrystal Shapeand Size Control: The Case of
CobaltVictor F. Puntes, * Kannan M. Krishnan, A. Paul Alivisatos
We show that a relatively simple approach for controlling the colloidal synthesis of anisotropic cadmium selenide semiconductor nanorods can be extended to the size-controlled preparation of magnetic cobalt nanorods as well as spher-ically shaped nanocrystals. This approach helps define a minimum feature set needed to separately control the sizes and shapes of nanocrystals. The resulting cobalt nanocrystals produce interesting two- and three-dimensional super-structures, including ribbons of nanorods.
Nanoscience
though most inventions
begin as fictions …
NanofictionNanotechnology
Early Nanotechnology
© Foresight Institute
• composites• coatings• lubricants• fabrics• enhanced plastics
the Road Towards Nanotechnology
Norman Poire, Merrill Lynch
Emerging “Molecular Electronics”
Goals:
- high speed
- low power
- high density
- ‘quantum’ devices
Candidates:
- polymers
- dendrimers
- metallorganics
- nanowires / nanotubes
Nanotubes & nanowires bridge the gap to the molecular world:
contactable systems with extended, low-D electronic states
1 µm100 µm
0.1 µm
Carbon Nanotube Electronic Circuits
Carbon Nanotubes
Martel APL 73 2447 (1998)IBM Yorktown
Semiconducting Nanotubes as Field-Effect Transistors
Nanotube FET Si p-MOSFET
Rc : 90 Ω µm 100 Ω µm
µ : > 10,000 cm2/Vs 100 cm2/Vs
G: 1260 µS/µm 430 µS/µm
Emerging “Molecular Electronics”
can molecular circuitry
compete with $0.0000001products ?
Chemical Sensing using Molecular Electronics
0.12
4
12
4
102
4
I (nA
)
1614121086420t (min)
Room temperature response to four short pulses of NH3
Sensor Prototype
NH3 response
20% O2T = 290K
Collins et al, Science (2000)
t (min)
275
250
2250 100 200 300 400 500
R (k
ohm
)
pure N2
Antibody Fragments
Proteins and Peptides
Atoms and Clusters
Coating Nanotubes for Chemical Function
Protein-coatednanotube
Selective Biological Sensing
A. Star Nanolett. (2003)Nanomix Research
Sour
ce-D
rain
Cur
rent
(µA
)
Biotin-labelledNanotube transistor
0.0
0.4
0.8
1.2
-10 0 10
Gate Voltage (V)
After Streptavidinbinding
V
Biotin
Streptavidin
CNT Circuit
Y. Cui Science (2001)Harvard Univ.
Goals for Single-Molecule Circuitry
1) Fabricate circuits with single active sites
2) Understand & enhance signal transduction
3) Identify and reduce noise sources
4) Time-resolved electrical measurements on molecular
binding events
INRF Device Fabrication
Engineering the Microworld at The University of California, IrvineUCI Integrated Nanosystems Research Facility
Local Electronic Characterization
Topography
Nanotube Topographyby AFM
Vtip
S D
EFM – electrostatic force microscopyKFM – Kelvin force microscopySGM – scanned gate microscopy
VSD
VG
Local Electronic Characterization
Topography
Nanotube Topographyby AFM
Composite
Local ElectricPotential V(x)
KFM Potential Map
Local resistance at attachment sites
Circuits at the Nanoscale
• circuits, circuits, circuits
• semiconductor processing
• materials synthesis
• chemical attachments
• electronic characterization
• quantum electronics
• biofunctional circuits
Dr. Yuwei FanBrett GoldsmithAlex KaneDerek KingreyBucky Khalap
Jorge GuerraKeven Loutherback