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Nanotechnology http://nano.xerox.com/nano Ralph C. Merkle Xerox PARC www.merkle.com See http://nano.xerox.com/nanotech/talks for an index of talks Sixth Foresight Conference on Molecular Nanotechnology November 12-15 Santa Clara, CA www.foresight.org/Conferences
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Nanotechnologyhttp://nano.xerox.com/nano Ralph C. Merkle Xerox PARC www.merkle.com
Seehttp://nano.xerox.com/nanotech/talksfor an index of talks
Sixth Foresight Conference on Molecular NanotechnologyNovember 12-15Santa Clara, CAwww.foresight.org/Conferences
Manufactured products are made from atoms. The properties of those products depend on how those atoms are arranged.
Coal Sand Dirt, water and air Diamonds Computer chips Grass It matters how atoms are arranged
Today’s manufacturing methods move atoms in great thundering statistical herds • Casting • Grinding • Welding • Sintering • Lithography
The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not anattempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are toobig. Richard Feynman, 1959 http://nano.xerox.com/nanotech/feynman.html
Most interesting structures that are at least substantial local minima on a potential energy surface can probably be made one way or another. Richard Smalley Nobel Laureate in Chemistry, 1996
Nanotechnology(a.k.a. molecular manufacturing) • Fabricate most structures that are specified with molecular detail and which are consistent with physical law • Get essentially every atom in the right place • Inexpensive manufacturing costs (~10-50 cents/kilogram) http://nano.xerox.com/nano
Terminological caution The word “nanotechnology” has become very popular. It can be used indiscriminately to refer to almost any research area where some dimension is less than a micron (1,000 nanometers) in size. Example: sub-micron lithography
Possible arrangements of atoms What we can make today (not to scale) .
The goal of molecular nanotechnology: a healthy bite. .
Molecular Manufacturing We don’t have molecular manufacturing today. We must develop fundamentally new capabilities. . What we can make today (not to scale)
“... the innovator has for enemies all those who have done well under the old conditions, and lukewarm defenders in those who may do well under the new. This coolness arises ... from the incredulity of men, who do not readily believe in new things until they have had a long experience of them.” from The Prince, by Niccolo Machiavelli
We’ll start a major project to develop nanotechnology when we answer “yes” to three questions: • Is it feasible? • Is it valuable? • Can we do things today to speed it’s development?
Products Products Core molecular manufacturing capabilities Products Products Products Products Products Products Products Products Products Products Products Today Products Products Products Products Products Overview of the development of molecular nanotechnology Products Products Products Products Products Products Products Products
Two more fundamental ideas • Self replication (for low cost) • Programmable positional control (to make molecular parts go where we want them to go)
Von Neumann architecture for a self replicating system Universal Computer Universal Constructor http://nano.xerox.com/nanotech/vonNeumann.html
Drexler’s architecture for an assembler Molecular computer Molecular constructor Positional device Tip chemistry
Illustration of an assembler http://www.foresight.org/UTF/Unbound_LBW/chapt_6.html
Advanced Automation for Space Missions Proceedings of the 1980 NASA/ASEE Summer Study The theoretical concept of machine duplication is well developed. There are several alternative strategies by which machine self-replication can be carried out in a practical engineering setting. http://nano.xerox.com/nanotech/selfRepNASA.html
A C program that prints out an exact copy of itself main(){char q=34, n=10,*a="main() {char q=34,n=10,*a=%c%s%c; printf(a,q,a,q,n);}%c";printf(a,q,a,q,n);} For more information, see the Recursion Theorem: http://nano.xerox.com/nanotech/selfRep.html
Complexity of self replicating systems (bits) • C program 808 • Von Neumann's universal constructor 500,000 • Internet worm (Robert Morris, Jr., 1988) 500,000 • Mycoplasma capricolum 1,600,000 • E. Coli 9,278,442 • Drexler's assembler 100,000,000 • Human 6,400,000,000 • NASA Lunar • Manufacturing Facility over 100,000,000,000 http://nano.xerox.com/nanotech/selfRep.html
How cheap? • Potatoes, lumber, wheat and other agricultural products are examples of products made using a self replicating manufacturing base. Costs of roughly a dollar per pound are common. • Molecular manufacturing will make almost any product for a dollar per pound or less, independent of complexity. (Design costs, licensing costs, etc. not included)
How strong? • Diamond has a strength-to-weight ratio over 50 times that of steel or aluminium alloy • Structural (load bearing) mass can be reduced by about this factor • When combined with reduced cost, this will have a major impact on aerospace applications
How long? • The scientifically correct answer is I don’t know • Trends in computer hardware suggest early in the next century — perhaps in the 2010 to 2020 time frame • Of course, how long it takes depends on what we do
Developmental pathways • Scanning probe microscopy • Self assembly • Hybrid approaches
Moving molecules with an SPM (Gimzewski et al.) http://www.zurich.ibm.com/News/Molecule/
Self assembled DNA octahedron(Seeman) http://seemanlab4.chem.nyu.edu/nano-oct.html
DNA on an SPM tip(Lee et al.) http://stm2.nrl.navy.mil/1994scie/1994scie.html
Bucky tube glued to SPM tip(Dai et al.) http://cnst.rice.edu/TIPS_rev.htm
Building the tools to build the tools • Direct manufacture of a diamondoid assembler using existing techniques appears difficult (stronger statements have been made). • We should be able to build intermediate systems able to build better systems able to build diamondoid assemblers.
Diamond Physical Properties PropertyDiamond’s valueComments Chemical reactivity Extremely low Hardness (kg/mm2) 9000 CBN: 4500 SiC: 4000 Thermal conductivity (W/cm-K) 20 Ag: 4.3 Cu: 4.0 Tensile strength (pascals) 3.5 x 109 (natural) 1011 (theoretical) Compressive strength (pascals) 1011 (natural) 5 x 1011 (theoretical) Band gap (ev) 5.5 Si: 1.1 GaAs: 1.4 Resistivity (W-cm) 1016 (natural) Density (gm/cm3) 3.51 Thermal Expansion Coeff (K-1) 0.8 x 10-6 SiO2: 0.5 x 10-6 Refractive index 2.41 @ 590 nm Glass: 1.4 - 1.8 Coeff. of Friction 0.05 (dry) Teflon: 0.05 Source: Crystallume
A hydrocarbon bearing http://nano.xerox.com/nanotech/bearingProof.html
A planetary gear http://nano.xerox.com/nanotech/gearAndCasing.html
Molecular tools • Today, we make things at the molecular scale by stirring together molecular parts and cleverly arranging things so they spontaneously go somewhere useful. • In the future, we’ll have molecular “hands” that will let us put molecular parts exactly where we want them, vastly increasing the range of molecular structures that we can build.
Synthesis of diamond today:diamond CVD • Carbon: methane (ethane, acetylene...) • Hydrogen: H2 • Add energy, producing CH3, H, etc. • Growth of a diamond film. The right chemistry, but little control over the site of reactions or exactly what is synthesized.
A hydrogen abstraction tool http://nano.xerox.com/nanotech/Habs/Habs.html
A synthetic strategy for the synthesis of diamondoid structures • Positional control (6 degrees of freedom) • Highly reactive compounds (radicals, carbenes, etc) • Inert environment (vacuum, noble gas) to eliminate side reactions
The impact of molecular manufacturingdepends on what’s being manufactured • Computers • Space Exploration • Medicine • Military • Energy, Transportation, etc.
How powerful? • In the future we’ll pack more computing power into a sugar cube than the sum total of all the computer power that exists in the world today • We’ll be able to store more than 1021 bits in the same volume • Or more than a billion Pentiums operating in parallel
Space • Launch vehicle structural mass will be reduced by about a factor of 50 • Cost per pound for that structural mass will be under a dollar • Which will reduce the cost to low earth orbit by a factor of better than 1,000 http://science.nas.nasa.gov/Groups/Nanotechnology/publications/1997/applications/
It costs less to launch less • Light weight computers and sensors will reduce total payload mass for the same functionality • Recycling of waste will reduce payload mass, particularly for long flights and permanent facilities (space stations, colonies)
Disease and illness are caused largely by damage at the molecular and cellular level Today’s surgical tools are huge and imprecise in comparison http://nano.xerox.com/nanotech/ nanotechAndMedicine.html
In the future, we will have fleets of surgical tools that are molecular both in size and precision. We will also have computers that are much smaller than a single cell with which to guide these tools.
A revolution in medicine • Today, loss of cell function results in cellular deterioration: function must be preserved • With future cell repair systems, passive structures can be repaired. Cell function can be restored provided cell structure can be inferred: structure must be preserved
Cryonics 37º C 37º C Freeze Revive -196º C (77 Kelvins) Temperature Time (~ 50 to 150 years)