1. Nanoscience and Energy
Allen Hermann, Ph.D.
Professor of Physics Emeritus,
University of Colorado
Boulder, Colorado 80309-0390
USA
allen.hermann@colorado.edu

2. Lecture 1. Course Introduction and Definitions
History, and examples
in nature and man-made
Quantum nature- theory:
quantum confinement
Nanomaterials:
Dimensionality
Chemical varieties and shapes
Synthesis
Top-down: Lithography
Bottom-up: Self-assembly
Characterization and Handling
Measurements
Nanotemplates

3. Lecture 2. Nanocarbon
C60, CNT’s
Synthesis and e-beam lithography
Graphene (synthesis, relativistic
QM nature, transport)

4. Lecture 3. Energy and Nanotechnology
Review of Alternate Energy
Sources
Review of Electronic Properties of
Solids:
Free- electron Fermi gas
Energy bands in Solids
Semiconductors and doping
pn junctions
Amorphous semiconductors

5. Lecture 4. Solar cells: Motivation (examples) and Theory
pn junctions under illumination
Homojunctions
Open-circuit voltage, short-
circuit current
IV curve, fill factor, solar-to-
electric conversion efficiency
Carrier generation and
recombination
Defects and minority carrier
diffusion
Current due to minority carrier
diffusion:
Solution to the diffusion
differential equation under
Spatially-homogeneous
generation, and
under Inhomogeneous
generation
Effect of an electric field
Heterojunctions

6. Lecture 5. Experiment: Types of Solar Cells
•Generation I solar cells:
Single Crystal Si, Polycrystalline Si
Growth, impurity diffusion, contacts, anti-reflection coatings
•Generation II Solar cells:
Polycrystalline thin films, crystal structure, deposition techniques
CdS/CdTe (II-VI) cells
CdS/Cu(InGa)Se2 cells
Amorphous Si:H cells
•Generation III Solar Cells:
•High-Efficiency Multijunction Concentrator Solar cells based on
III-V’s and III-V ternary analogues
•Dye-sensitized solar cell
•Organic (excitonic) cells
•Polymeric cells
•Nanostructured Solar Cells including Multicarrier per photon cells,
quantum dot and quantum-confined cells

7. Lecture 6. Nanotechnology
Fuel Cells
Nano-composite materials
Nanoelectronics and photonic
Devices:
Chemical and Biological Detectors
Nanomedicine:
Disease Detection
Implants
Delivery of Therapeutics
Other nanomedicine
Applications
Risks

8. Lecture 7. Other Nanotechnology Applications
DNA sequencing
Filtration
Clothing and Sports
Composites
Other Nanomedicine Applications and Opportunities
Other Nanotemplate-based Applications:
Superconductors
Magnetic Nanowires
Ferroelectrics
Dielectric Nanostructures and Cloaking
The Business of Nanotechnology

9. Basis for Grade in the Course
Your grade in the course is based
on 2 factors:
1) class attendance
2)grade earned on the paper
assigned.

10. A 1-2 page paper in English is to be turned in to Prof.
Hermann by the end of the last lecture. Both a hard
copy and a digital copy emailed to
allen.hermann@colorado.edu
are required.
This paper should be in your own words.
The paper could contain one or more figures and/or
tables.
The subject matter should be either
1) a tutorial explaining clearly one topic from this
course (in greater detail than given in the course), or
2) a clear description of your own research related
to the subject of this course.

11. Your grade will be calculated as follows:
Attendance- 40% ( 5.71 % per class attended)
Grade for paper- 60%

13. Further References
1. Charles Kittel, “Introduction to Solid State Physics”, Prentice Hall
(1967 ff.)
2. S.M. Sze, “Physics of Semiconducting Devices”, John Wiley (1969,ff.)
3.Frank Larin, “Radiation Effects in Semiconducting Devices” (John
Wiley)
4. H.Y. Tada and J.R. Carter, JPL Solar cell Radiation handbook, NASA
(1977)
5. Martin Green, “Solar Cells”, Prentice Hall (1982,ff.)
6. H.J. Hovel, “Solar Cells”, in Semiconductors and Semimetals, Vol.11
(edited by R. Richardson and A. Beer, Academic Press, 1975).
7. J. Reynolds and A. Meulenberg, J.Appl. Phys. 45, 2582(1974)

14. Lecture 1
Course Introduction and
Definitions

15. Lecture 1. Course Introduction and Definitions
History, and examples
in nature and man-made
Quantum nature- theory:
quantum confinement
Nanomaterials:
Dimensionality
Chemical varieties and shapes
Synthesis
Top-down: Lithography
Bottom-up: Self-assembly
Characterization and Handling
Measurements
Nanotemplates

16. 10,000 Kilometers

17. 1000 km

33. Sliding scale universe:
http://htwins.net/scale2/scale2.swf?bordercolor=white

34. What is Nanotechnology?
• Research and technology development at the atomic, molecular
or macromolecular levels, in the length scale of approximately 1
- 100 nanometers.
• Creating and using structures, devices and systems that have
novel properties and functions because of their small and/or
intermediate size.
• Ability to control processes at a few nm-range for advanced
material processing and manufacturing.

40. The Scale of Things – Nanometers and More
Things Natural Things Manmade
10-2 m 1 cm
10 mm
Head of a pin
1-2 mm The Challenge
Ant 1,000,000 nanometers =
~ 5 mm 10-3 m 1 millimeter (mm)
Microwave
MicroElectroMechanical
Dust mite (MEMS) devices
10 -100 mm wide
200 mm 10-4 m
0.1 mm
100 mm
Microworld
Fly ash
Human hair ~ 10-20 mm
~ 60-120 mm wide
O
P
O O
-5
10 m 0.01 mm O O O O
10 mm O O O O O O O O
Pollen grain
Red blood cells
O O O O O O O O
Infrared
S S S S S S S S
Red blood cells
(~7-8 mm) Zone plate x-ray “lens”
1,000 nanometers =
10-6 m 1 micrometer (mm) Outer ring spacing ~35 nm
Visible
Fabricate and combine
nanoscale building
blocks to make useful
10-7 m 0.1 mm devices, e.g., a
100 nm photosynthetic reaction
Ultraviolet
center with integral
semiconductor storage.
Nanoworld
Self-assembled,
0.01 mm Nature-inspired structure
10-8 m Many 10s of nm
~10 nm diameter 10 nm
Nanotube electrode
ATP synthase
10-9 m 1 nanometer (nm) Carbon
buckyball
Soft x-ray
~1 nm
diameter
Carbon nanotube
~1.3 nm diameter
DNA 10-10 m Quantum corral of 48 iron atoms on copper surface
0.1 nm
~2-1/2 nm diameter Atoms of silicon positioned one at a time with an STM tip
spacing ~tenths of nm Corral diameter 14 nm

43. My Personal Early Nanotechnology
Motivation

44. Li+
Li PVP-I CT
LiI
complex

47. 20 nm nanorods of MnO2 for positive electrodes
in Li ion batteries

50. • Quantum Confinement
• One Dimension

56. • Quantum Confinement
• Three Dimensions

58. For absorption,
energy of photon absorbed goes
as 1/L2,
smaller particle absorbs larger
energy photon, who’s wavelength
is smaller (toward blue), and longer
wavelength photons (toward red)
are transmitted.

59. Figure 7.2. Solutions of quantum dots of varying size. Note the variation
in color of each solution illustrating the particle size dependence of the
optical absorption for each sample. Note that the smaller particles are in
the red solution (absorbs blue), and that the larger ones are in the blue
(absorbs red).

61. For light scattering,
the photon wavelength must be
smaller than the particle size, and
the smaller particles tend to
scatter only the shorter
wavelength photons (toward blue)

63. .Nanomaterials
• C. Dimensionality
• D. Chemical varieties
• E. Shapes
• F. Synthesis
– 1. Lithography
– 2. self-assembly

68. • Synthesis
1. Lithography

69. Exposing
Radiation
Polymer Resist
Thin Film
Substrate
Positive Negative
Developing
Resist Resist
Etching and
Stripping
Figure 1.1. Schematic of positive and negative resists.

71. Figure 1.6. Schematic of a focused ion beam system.

72. Carbon Nanotubes/Nanocones with Various Catalyst Patterning Dimensions
by E-beam Lithography
30
0n
40
m
0n
1m
12
m1
0n
m
60
m
20
60
nm
0n
nm
80
m
nm
10
0n
m
nm
100

81. Figure 2.1. The process of forming a self-assembled monolayer. A
substrate is immersed into a dilute solution of a surface-active
material that adsorbs onto the surface and organizes via a self-
assembly process. The result is a highly ordered and well-packed
molecular monolayer. (Adapted from Ref. 9 by permission of
American Chemical Society.)

87. .Characterization and Handling
– a. Optical Tweezers
– b. Electromagnetic tweezers
– c. In nanotemplates
– d. Structural Analysis by TEM, SEM, X-ray, etc.

91. Ballistic Nanotube MOS Transistors (Chen,Hastings)
Placement of Nanotubes by E-Field
D Nanotube Field-Effect Transistor(FET)
(The first-demo) Al-Gate SWNT
L Drain
Source
d HfO2
W
L
Ti
SiO2 L~20 nm
E-Beam Lithography

92. • Measurements

93. Coarse approach
mechanism
Reference
S
c
a feedback
n
n data
-
e
r
Signa l
Sensor
Sample
Figur e 3.1. Schematic showing all major
components of an SPM. In this example,
feedback is used major components
all to move the sensor
Figure 3.1. Schematic showingmaintain a constant signa l. of an SPM. In
vertically to
this example, feedback is used to movethe sensor is taken
Vertical displacement of the sensor vertically to
as topograph ical data.
maintain a constant signal. Vertical displacement of the sensor is
taken as topographical data

95. Clean Room
Major equipment
Photolithography Plasma
Enhanced
• Focused Ion Beam System (FIB) (scheduled for installation in mid 2007) Chemical
• Atomic Layer Deposition System (ALD)
Vapor
• Rapid Thermal Processing System (RTP)
• Plasma Enhanced Chemical Vapor Deposition System (PECVD) Deposition
• Standard Resolution Electron Beam Lithography (EBL)
• Atomic Force Microscope for Nanopatterning, and Manipulation (AFM)
• Atomic Force Microscope for Atomic Resolution Imaging (AFM)
• Quartz Crystal Microbalance (QCM)
• 4-furnace bank of 3-zone oxidation, dopant diffusion, and annealing furnaces
• Class 100 Clean Room
• Spin-Coating Station
• Photolithography System
• Surface Profiler Reactive Ion Etching
• Chemical Treatment Station (cleaning, etching, and functionalization)
• Ion Milling System
• Plasma Cleaning/Oxidation System
• Gas Cabinet Bank
• Experimental Materials Thermal Evaporator
• Standard Materials Thermal Evaporator
• Electron-Beam Evaporator
• Multi-target Sputtering System
• Probe Station and Device Characterization System
• Four-Point Resistance Measurement System Atomic
• Ellipsometer Layer
• Optical Microscopes Deposition
• Dicing Saw Quartz MicroBalance
• Equipment Cooling Systems (3)
• Inductive Coupled Plasma (ICP) Etching System (scheduled for installation in Feb. 2006)
• Experimental materials sputtering system (scheduled for installation in mid 2006)
• Ultra-High Resolution EBL and SEM System
Rapid Thermal
Processing

96. IV. Nanotemplates
• G. Inorganic
• H. Organic

98. Fig.2 (a) Nanostructure of anodically formed Al2O3 template. (b) its cross-section,
(c) catalyst deposited at the bottom of the pores, (e) vertically aligned nanotubes, and (f) TEM
image of a nanotube.

99. Nano-scale Material Research
(Chen, Singh, DeLong, Saito, Yang, Bhattacharyya, and Sumanasekeras)
The first vertically aligned nanotubes on silicon substrates using templates
200nm (b)
200 nm
(d)
Nano-template Catalyst
(a) (c)
Hexagonal Cells
SiO2 Al
SiO2
Vertically aligned MWNTs
Horizontally
aligned embedded in AAO insulator
SiO2
Si substrate Carbon nanotubes

100. • Fig. 3 Schematic representing the helix-coil transitions within the pore of a
Poly-L-Glutamic Acid functionalized membrane (a) random-coil formation at
PH > 5.5 , (b) helix formation at low pH ( <4 ).