Nanoscience I Introduction and overview - Prujut · PDF fileNano-1 Kai Nordlund, Department of...
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Nano-1
Nanoscience I Introduction and overview
Kai Nordlund19.9.2010
Faculty of Science
Department of Physics
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Contents
What is nanoscience and technology?
Why the courses Nanoscience I – IV?
Why is nanoscience new?
Background: visions of Feynman and Drexler
Reality nowResearchHistorical and natural nano Industry and markets
- Finland- World
Future: modern visions and time scales
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
What is nanoscience?
”Nanoscience deals with the scientific study of objects with sizes in the 1 -- 100 nm range in at least one dimension. The objects are controlled on this size scale either in terms of manufacturing, modification or analysis, and the research includes some aspect of novelty either in terms of material studied, methods used or question asked.”
- Kai Nordlund 2005
Synthesis of more authoritative sources; very inclusive definition
Three crucial aspects:Novelty (~ 1980 – 1990 onwards )Controllability Includes parts of physics, chemistry, engineering, bio- and medical
sciences
Nanotechnology: Related to nanoscience as science and technology usually are
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Alternative definitions
Nanoscience does not have a single unique definition
The original one:
“Nano-technology mainly consists of the processing of separation, consolidation, and deformation of materials by one atom or one molecule”
- Norio Taniguchi 1974 - By current standards clearly too narrow
The ‘most official’ Finnish definition, by the nanoscience workgroup of the Ministry of Education 2006 (non-Finnish-speakers, sorry…):
Tutkimusmenetelmien ja teknologian kehittämistä makro- ja mikromaailmasta poikkeavien nanomittakaavan uusien ilmiöiden ja prosessien tutkimiseksi
Uusien funktionaalisten atomi- ja molekyylitason materiaalien, rakenteiden ja laitteiden karakterisoimista, mallintamista, suunnittelemista ja valmistamista
Uusien nanomittakaavan ilmiöiden ja rakenteiden manipuloimista ja kontrolloimista atomi- ja molekyylitasolla
There is a certain tendency by some scientist to give up the requirement of novelty, but this is problematic:
Without ‘novelty’ suddenly almost all chemistry, biochemistry and materials physics would be nanoscience
Also, does not correspond to common perception that nanoscience is new
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
How small is a nanometer?
D ~ 1 nm
Dearth /Dball = Dball /Lfullerene
D ~ 13000 km
D ~ 0.3 m
Let’s remind ourself of how small a nanometer really is
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why the courses Nanoscience I –
IV?
Nanoscience is clearly interdisciplinary: it includes many branches of science, and the traditional borderlines are often not meaningful any more
In the spring of 2005 a desire to create a truly crossdisciplinary nanoscience teaching was formed within “Helsinki-Nano” and the National Graduate School in Nanosciences (NGS-NANO)Multiple top-level lecturers to ensure best possible expertiseNanoscience is broad: big programme necessary
Original idea:Prof. Dennis Bamford (Viikki), Acad. Prof. Olli Ikkala (Otaniemi)
Other key developers:
Prof. Marjo Yliperttula (Viikki), Doc. Marc Baumann (Meilahti), Doc. Sami Franssila (Otaniemi), Akat. Prof. Olli Ikkala (Otaniemi), Prof. Juhani Keinonen (Kumpula), Prof. Risto Kostiainen (Viikki), Prof. Seppo Meri (Meilahti), Prof. Marja-Liisa Riekkola (Kumpula), Akat.Prof. Risto Nieminen (Otaniemi), Dr. Runar Törnqvist (Otaniemi), Prof. Kai Nordlund (Kumpula)
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Practical issues
Course coordinators 2010-2011: I: [email protected] II: [email protected], III: [email protected]
Course assistant, courses I-II:[email protected]
Nanoscience I: 2 ov
or 3 op (=ECTS credits)
Mon 16-18 room E207 Physicum
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Course contents
Nanoscience I: Why is nano different Introduction for BSc and MSc students
Nanoscience II: Nanomaterials
Nanoscience III: Nanotechniques
http://www.physics.helsinki.fi/courses/s/nanotiede/ Lecture materials: id “nano”, password “science”Videos: id “Nano”, password “Science”
Exam based on lectures and print-out material
- Exam is in the form of a cheat-sheet one: you may bring one A4 single-sided fully handwritten page of notes with you. Note: only 1 A4 and only handwritten.
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Literature
Nanoscience does not yet have well-established standard books (like say “Ashcroft-Mermin” in solid state physics or “Atkins” in physical chemistry)
Best overview textbooks we know of:
Gabor L. Hornyak, H.F. Tibbals, Joydeep Dutta, Anil Rao, Introduction to Nanoscience
(CRC, USA, 2008), ISBN-13: 978-1420048056, £38.94 on 19.9.2010
Charles P. Poole, Frank. J. Owens, Introduction to nanotechnology (John Wiley & sons, Hoboken, New Jersey, USA, 2003) ISBN 0-471-07935-9. £71.73
amazon.co.uk 19.9.2010
Good intro to soft matter nanoscience:
C. Niemeyer, C. Mirkin (eds): Nanobiotechnology (Wiley-VCH Verlag, Weinheim, Germany, 2004), ISBN 3-527-30658-7
- Copies of critical sections will be provided for printout
Really easy-to-read introduction, cheap, but of course not deep:
Nanotechnology for dummies (R. D. Booker, E. Boysen, Wiley 2005)
Numerous encyclopedias already exist, but are expensive
And often not well edited: coherence and some articles may be poor
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
So why is nano new ?
The nano- (meso-) scale has of course been known to exist ever since the size of atoms was determined about 100 years ago
But after that science was pretty much divided into two parts:Atomic physics focused on atoms
- Nuclear and particles physics kept going downwards in size
Materials physics, chemistry and metallurgy focused on the properties of continuum matter
- Molecules and colloids were of course studied, but the primary interest was their macroscopic average properties
The nanoscale, properties of individual nanoobjects when they differ from bulk, was left in between, but most people were not really interested in them
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why is nano new?
An excellent example on that nano was not of interest to many is the discovery history of carbon nanotubes
These are pretty much the prototype material for nanoscience. Often the credit to finding them is given to Sumio Ijima who described them in 1991.
But but:Russian scientists probably made tubes in 1952
R. Bacon, National Carbon Comp., Parma, Ohio
probably produced them in 1960.
M. Endo, Japani, produced and described them
in 1977, and published it in J. Non-Cryst. Solids
P. Wiles, University of Canterbury, New Zealand
produced and described them in 1979
But nobody cared: time was not ripe for ‘nano’
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why
is nano different?
Example 1:
atom ball
What fraction of atoms are on the surface of a sphere?
We know one atom layer is about t=0.2 nm thick
Volume of surface atoms:
Vsurface = 4 r2 t
Volume of the whole ball:
Vball = 4 r3/3
Ratio, i.e. fraction of surface atoms:
Vsurface / Vball = 3 t / r
Consider different values of r:
Macro ball: r= 1 m => 3 t / r = 6 • 10-10
Micro ball: r= 1 m => 3 t / r = 6 • 10-4
Nano ball: r= 1 nm => 3 t / r = 0.6 !!
On the nanoscale the fraction of surface atoms is enormous!
From surface science we know these behave differently from the bulk => huge effects on material properties!
More on my 3rd lecture
0.2 nm
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why
is nano
different?
Example 1:
implications...
Since the surface area ratio is very large, a very small amount of matter is enough to give a huge surface area Important in any kind of application where surfaces are utilized: catalysis,
optical effects, etc. etc.
Imagine taking e.g. a 1.7 cm size cube and divide it into 8 24 times => you get 1 nm side cubes with the same surface area as a football field
Repeat 24 times
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why
is nano different?
Example 2:
Quantum mechanics changes materials properties
If the length scale of an atomic structure is smaller than the characteristic wavelength of electrons, the electron may be ”confined” in 1, 2 or 3 dimensions The electron ‘wavelengths’ are typically on the nanometer scaleOne can talk about 2D, 1D and 0D-structures depending on how
many dimensions are in the nanometer scale 2D-nanostructure: thin film / quantum
well, electrons confined in 1 dimension 1D-nanostructure: nanowire / quantum
wire, electrons confined in 2 dimensions 0D-nanostructure: nanoparticle /
nanocluster / quantum dot, electrons confined in all 3 dimensions
[“Quantum corral”, IBM]
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Why
is nano different?
The density of states of electrons is dramatically different when one lowers the number of dimensions: 3D: continuous 2D: steps 0D: only peaks!
In a quantum dot the electron states are quantized just like in atoms
But the advantage is that the size of a quantum dot may be changed!An atom is an atom
More on this on Risto Nieminens lecture
Photoemission from CdSe nanoparticles of different size
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Bottom-up vs. top-down and self- assembly
These are three key concepts in nanoscience
Bottom-upBuilding something from atoms up If done manually by human control,
really slow and inefficientPossible solution: self-assembly (≈self-
organization): atoms find desired positions by themselves by some mechanism in nature
Top-downStart from macroscale and miniaturizePrime example: Si chip technologyWorks: Intel and AMD chips > billion (109)
nanoscale components that all work
Modern nanoscience often combination of the two
[IBM]
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Background: the speech of Feynman
The origin of nanoscience can be traced back to a speech which the Nobel laureate in physics Richard Feynman held in 1959 with the title ”There is plenty of room at the bottom”.
Amazingly, many of the most important ideas in nanoscience which are relevant now can be found already in this talkWhole speech available on course web
page, and easily found in the web (google on Feynman and the title)
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Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: role in science
“I would like to describe a field, in which little has been done, but in which an enormous amount can be done in principle. This field is not quite the same as the others in that it will not tell us much of fundamental physics (in the sense of, ``What are the strange particles?'') but it is more like solid-state physics in the sense that it might tell us much of great interest about the strange phenomena that occur in complex situations. Furthermore, a point that is most important is that it would have an enormous number of technical applications.”
Nanoscience does not answer fundamental questions about why the universe exists etc. It is from atoms up.Well known atom-level quantum physics and chemistry underlies it
all One can nevertheless find science-philosophical aspects in
nanoscience (emergence, complexity etc.)- But that is beyond the scope of this course
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Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: miniaturisation
”Why cannot we write the entire 24 volumes of the Encyclopædia Britannica on the head of a pin? “ Feynman calculated that if one can make atom structures
with the width of 40 atoms, one could write the whole Encyclopædia Britannica on the head of a pin
In 1959 this was clearly impossible Feynman was ridiculed for the notion
Today this could be achieved literally!At least if the pin had an Si head (electron beam lithography)
In practice of course nobody would want to do it: DVD’s or USB-sticks work much better
But the vision of Feynman has essentially been realized
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: electronics miniaturisation
“I don't know how to do this on a small scale in a practical way, but I do know that computing machines are very large; they fill rooms. Why can't we make them very small, make them of little wires, little elements---and by little, I mean little. For instance, the wires should be 10 or 100 atoms in diameter, and the circuits should be a few thousand angstroms across. “.
This is literally true in Si technology!
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Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: manipulation of atoms
“But I am not afraid to consider the final question as to whether, ultimately---in the great future---we can arrange the atoms the way we want; the very atoms, all the way down! What would happen if we could arrange the atoms one by one the way we want them (within reason, of course; you can't put them so that they are chemically unstable, for example).
This has been realized, on surfacesBut there is a catch
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: connection of physics, chemistry and biosciences
“This fact---that enormous amounts of information can be carried in an exceedingly small space---is, of course, well known to the biologists, and resolves the mystery which existed before we understood all this clearly, of how it could be that, in the tiniest cell, all of the information for the organization of a complex creature such as ourselves can be stored. “ …“The theory of chemical processes today is based on theoretical physics. In this sense, physics supplies the foundation of chemistry. But if the physicists [had a hundred times better electron microscope], they could also dig under the chemists in the problem of chemical analysis. It would be very easy to make an analysis of any complicated chemical substance; all one would have to do would be to look at it and see where the atoms are.”
=> In close-to-atomic level science physics, chemistry and biology get a natural connection.
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Feynman’s speech: bio-
and nanomachines
“Biology is not simply writing information; it is doing something about it.” … “What are the possibilities of small but movable machines?” … “A friend of mine (Albert R. Hibbs) suggests a very interesting possibility for relatively small machines. He says that, although it is a very wild idea, it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and ``looks'' around. It finds out which valve is the faulty one and takes a little knife and slices it out.
This is one of the most ambitious visions of nanoscience: nanomachines
of complex and controlled functionality
“Nanosurgeon” concepts popular in science fiction introduced here
Man-made complex nanomachines were utopian in the 1950’s, and they still are
On the other hand, biology has nanomachines which definitely work
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
The visions of Drexler
In 1986 K. Eric Drexler took the visioning of nanotechnology even further in his book “Engines of Creation: The Coming Era of Nanotechnology”
Basic ideas same as those of Feynman
He described a world with self-replicating nanomachines which can go into cells and repair cancer
On the other hand he also described nanomachines and nanoweapons ”Gray goo”: self-replicating nanomachines
that eat up everything in their way
This idea even Drexler himself has taken back us unrealistic [afterword of the 1990 edition of the book]
[Picture from web site of Drexler’s Foresight institute]
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Reality now
The visions of Feynman and Drexler have been inspiring, but almost certainly nanoscience would have appeared anyway because of independent developments in science, e.g:Atomic force microscopySilicon technology Fullerenes, atom cluster science
I will now present examples of real nanoscience and technology
The interest into this has been in a steady rise since 1995Unfortunately some is just
relabeling of old science
[Scientific publications in the abstract databases Web of Science (all science) with the word nano- anything in the title, keywords or abstract. The physics part is for a search limited to materials physics and physical chemistry classifications. Data collected by Kai Nordlund 2010]
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Reality now: Building one atom at a time
Can be done on surfaces with atomic force microscopes!
[“Quantum ring”, IBM]
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: atom level transistors
A nanotube transistor, where electricity is conducted in a single carbon moleculeRealized also in Finland
Some of these can function with single electrons
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanotweezers
C. Lieber, Harvard University
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanomachines
1
In Aarhus University in Denmark a molecule has been fabricated which moves on metal surfaces and picks up atoms one at a timeAtomic harvester
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanomachines
2
Nanorotor
[1939rotor.gif]
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Kai Nordlund, Department of Physics, University of Helsinki
BUT: Nothing new under the sun…
There are already nanostructure-based products in history
In glass manufacturing metal nanoparticles have long been used to modify the color of glasses Exciting optical effects Lycurgys cup from the 3rd century
“Wootz”-steel in the original Damascene swordsNanoparticles gave superior properties
[Verhoeven, Scientific American 284 (2001) 62]
But these did not fulfill the nano criterion “controllable” The processes were not understood, and the
manufacturing technology eventually vanished
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Kai Nordlund, Department of Physics, University of Helsinki
Nano in nature
Biology of course works starting from the nanoscaleBut biology
and biochemistry with the aim to understand how living beings works is not nanoscience by itself
But if biological structures are modified by humans with the aim to achieve new kinds of functionality, this may be nanoscience
Nature can inspire nanoscience “Biomimetics”
Nanoparticles exist in natureNatural aerosol nucleation is
basically similar as that of artificial nanoparticles
Important for pollution, but understanding has only recently been achieved
[Hanna Vehkamäki, UH]
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Kai Nordlund, Department of Physics, University of Helsinki
Nanomachines
in nature
The proof that nanomachines with complex functionality may exist comes from nature, e.g. so called ATP-synthases These are really like a machine
with mobile parts The upper part of the
machine is located in an isolating cell membrane
Above the membrane the proton (or sodium) ion concentration is higher than below, which drives the machine
The machine makes the cells energy source ATP from ADP, or can also run in the reverse
Animation ATPsynthase.mov from course web page (quicktime)
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Kai Nordlund, Department of Physics, University of Helsinki
Modifying natural nanomachines
ATP synthase is fascinating bioscience, but not nanoscience by itself
But one of the most promising approaches for making nanomachines is to artificially modify the components of nature for human use
This has been done for ATP synthase
An actine molecule was added to the end, which the synthase then rotated like a propeller!
Movie 104705a.mov (quicktime)[Sambongi, Science 286 (1999) 1722]
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanomarkets
Nanotechnology is not limited to research!
It already now has a big market
Giving numbers to this is difficult, as it depends on what is counted in
A synthesis by Markku Lämsä (TEKES) from different sources:
Wor
ld m
arke
t of n
anot
ech
(GU
SD)
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanoproducts
There are plentyHere is just a couple of examples:
Cheaper or better mobile phones Combined chips in the phonesNanotubes for heat conductanceCoatings to which fingerprints
do not stick
Textiles and windows into which dirt does not stickNanometer-large molecules, which prevent
dirt from sticking to the surface or make it break up
- Window panes that clean up during rain
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanoproducts
Car exhaust catalysis is one of the biggest and most important products that can be counted as nanotech
Their functionality is based on Pt/Pd/Rh-nanoparticles which break up harmful hydrocarbons, carbon monoxide and nitrogen oxides thanks to surface catalysis
Due to the high prize of the metals, it is completely crucial to have them in nanoparticle form
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanoproducts
in Finland
Also in Finland people have managed to commercialize nanotechnology
Atomic Layer Deposition was invented in FinlandPlanar electroluminescent displaysYear 2006 in Intel chips
Orion DiagnosticaNanoparticles to detect molecules
in the medical industry
Liekki OyActive optical fibersDirect Nanoparticle Deposition
Montreal Sports Oy Icehockey clubs and baseball bats
strengthened with carbon nanotubes- nanotube epoxy from Amroy Oy
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Kai Nordlund, Department of Physics, University of Helsinki
Reality now: nanoproducts
in FinlandFINNAIR
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Kai Nordlund, Department of Physics, University of Helsinki
Future: somewhat realistic visions
My completely personal guess over important nano products which have good odds at being realized within 5-20 years
Don’t take this too seriously, in 10 years you will laugh at me for this!
1. Carbon nanotubes which strengthen materials and make the heat or electrically conductive
Already on the market, but better will come
Will there be materials orders of magnitude stronger than steel??
2. Molecules which can take medical molecules to desired places in the body
Intensive research is ongoing
3. New cheap solar cell materials??
Can something really revolutionary be achieved??- If it is, may have huge effect on world energy production
4. Molecular electronics
Something will certainly come up, but can mainstream Si be beaten?
Si nanowires as key transistor parts very promising
5. Hydrogen storage in nanomaterials???
Could have a dramatic impact on the hydrogen economy
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Kai Nordlund, Department of Physics, University of Helsinki
Future: how about the really wild visions?
It is already clear that nanoscience has and will have an important role in technology which affects our daily life
But how about the really wild visions?
Building one atom at a time in 3D will probably not be realized as in the original vision Fundamental problems and too laborious
The nanomachine concept
as presented
by Drexler as a miniaturization of conventional metals industry will certainly not be realizedMetals behave fundamentally different on the nanoscale
On the other hand nanomachines
based on biology will
certainly be realized at least in the labsBut “upscaling” and controllability of these ??
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Future: the wildest vision
The wildest vision which really would change things, which is seriously researched, is the space elevator Old idea, e.g. Arthur C. ClarkeConventional materials are not strong
enough
But carbon nanotubes are in theory strong enough to make it possibleNASA has a small project on this
No one has found fundamental reasons preventing it
But the practical problems are rather considerable:E.g. a 50 km high tower as the bottom…Estimated time scale 100 years…
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Kai Nordlund, Department of Physics, University of Helsinki
Ethics and risks
Like any new technology, nanoscience may lead to dangerous uses, intentionally or unintentionally
In popular culture, science fiction books inspired by Eric Drexler’s wilder visions have given nanoscience a slightly bad reputation This is unfortunate, as they are largely based on the “gray goo” idea
which even Drexler himself has taken back!
On the other hand, there are real and serious security concerns already now E.g. what are health effects of metal nanoparticles and nanotubes? These are already formally regulated by e.g. the EU chemicals
directives, but there still is pretty little research on safe levels Initial studies seem to indicate some nanoparticles may be harmful,
but not nearly as bad as e.g. asbestosis
Risks should neither be exaggerated nor ignored!
Kaarle Hämeri will talk more about this on the course
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Kai Nordlund, Department of Physics, University of Helsinki
Summary: history of nanotechnology
1950 1960 1970 2010200019901980
Insp
iratio
nD
isco
verie
san
d in
vent
ions
1959: Speech of Feynman
1974: First known definition of term by Norio Taniguchi
1986: “Engines of Creation published by Eric Drexler
1981: Scanning Probe Microscopy
1983: Fullerenes
~ 2000: Aberration- corrected TEM’s
1965 – Miniatyrization of Si integrated circuit processing
1991: Carbon nanotubes
2004: Graphene
Nano-1
Kai Nordlund, Department of Physics, University of Helsinki
Summary: future of nanotechnology??
2050 220021502100
Targeted drug delivery
The space elevator
Single- molecule Si chips
You??
Nanosurgeons
Cure of all cancers