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8/9/2019 Presentation from 2009 Dinner Meeting
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Systems Engineering forSystems Engineering for
NanosystemsNanosystems
Belle Consulting Services Inc.Belle Consulting Services Inc.
Dr. Gabriele BelleDr. Gabriele Belle
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Introduction to NanosystemsIntroduction to Nanosystems
What is a Nanosystem?What is a Nanosystem? Why are we interested in the development of Nanosystems?Why are we interested in the development of Nanosystems?
What is the market for nanoscale devices and systems?What is the market for nanoscale devices and systems?
ApplicationsApplications
What are the most significant physical properties thatWhat are the most significant physical properties thatdistinguish nanoscale systems from larger systems?distinguish nanoscale systems from larger systems?
DevicesDevices
The Systems Engineering PerspectiveThe Systems Engineering Perspective
ChallengesChallenges
ConclusionConclusion
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What is a Nanosystem?What is a Nanosystem?
Nanotechnology is based on the exploitation of new materialproperties, processes, and functionalities that matter exhibitsat sizes between 1 nm and 100 nm.
The effects related to the size produce qualitatively newbehavior.
When the sample size or grain size becomes comparable withthe mean free path of a particle, then the correspondingphysical phenomenon will be strongly affected.
To be able to identify and characterize nanoscale phenomenait is necessary to directly probe the small devices. This ischallenging because, sub micron devices produce tiny signalsin almost all relevant physical measurements.
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Why are we interested in theWhy are we interested in thedevelopment of Nanosystem?development of Nanosystem?
HistoryHistory Moores Law: In 1965 Gordon Moore, one of the foundersMoores Law: In 1965 Gordon Moore, one of the founders
of Intel Corporation, predicted that the number ofof Intel Corporation, predicted that the number oftransistors that could be fit in a given area would doubletransistors that could be fit in a given area would doubleevery 10 months for the next ten years.every 10 months for the next ten years.
This trend continued past the ten yearsThis trend continued past the ten years
2000 transistors in the 4004 processors in 19712000 transistors in the 4004 processors in 1971
40,000,000 transistors in the Pentium 440,000,000 transistors in the Pentium 4
Decrease in size (millimeters in 60s to 45Decrease in size (millimeters in 60s to 45--65 nm today)65 nm today)
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Why are we interested in theWhy are we interested in thedevelopment of Nanosystem?development of Nanosystem?
History continued:History continued:
1960: William McLellan1960: William McLellanconstructed the first nanomotorconstructed the first nanomotor
1985: Tom Newman was able to1985: Tom Newman was able toscale down letters such that thescale down letters such that theentire Encyclopedia Britannica fitentire Encyclopedia Britannica fitonto the head of a pin.onto the head of a pin.
1985 Discovery of fullerenes and1985 Discovery of fullerenes and
later carbon nanotubeslater carbon nanotubes
Carbon NanotubeSource: Wikipedia
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Why are we interested in theWhy are we interested in thedevelopment of Nanosystem?development of Nanosystem?
HistoryHistory
Advances in biochemistry made the synthesis of larger andAdvances in biochemistry made the synthesis of larger and
more complex structures, up to tens or hundreds ofmore complex structures, up to tens or hundreds of
nanometer in size, possible.nanometer in size, possible.
Lasertechnology and advances in the production andLasertechnology and advances in the production and
development of photonic devices offer new possibilities ofdevelopment of photonic devices offer new possibilities of
manipulating and using light. We can produce nanoscalemanipulating and using light. We can produce nanoscale
optoelectronic devices and integrate these devices intooptoelectronic devices and integrate these devices into
other Nanosystems.other Nanosystems.
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Why are we interested in theWhy are we interested in thedevelopment of Nanosystem?development of Nanosystem?
Three powerful technologies have met on acommon scale the
NANOSCALENANOSCALE
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What is the market for nanoscaleWhat is the market for nanoscaledevices and systems?devices and systems?
Nanotechnology isNanotechnology isconsidered theconsidered themanufacturing wave ofmanufacturing wave ofthe future.the future.
Industry leadersIndustry leadersbelieve that in 10 to 15believe that in 10 to 15years the globalyears the globalmarket formarket for
nanotechnologynanotechnologyproducts will exceed $1products will exceed $1Trillion Dollar annually.Trillion Dollar annually.
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ApplicationsApplications
MedicineMedicine
ChemistryChemistry
EnergyEnergy Information andInformation and
CommunicationCommunication
Heavy IndustryHeavy Industry Consumer GoodsConsumer Goods
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Applicat ion: MedicineApplicat ion: Medicine
Diagnostics
Drug Delivery
Tissue Engineering
Source: Wikipedia
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Applicat ion: ChemistryApplicat ion: Chemistry
SynthesisSynthesis -- provides novelprovides novelnanomaterialsnanomaterials
SelfSelf--assembly of moleculesassembly of molecules
CatalysisCatalysis -- benefits frombenefits fromnanoparticles for applications in fuelnanoparticles for applications in fuelcellscells
FiltrationFiltration waste and waterwaste and water
treatment, air purification, energytreatment, air purification, energystorage. Use of membranes, wherebystorage. Use of membranes, wherebythe liquid is pressed through thethe liquid is pressed through themembrane. Nanofiltration is used formembrane. Nanofiltration is used forthe removal of ions and thethe removal of ions and theseparation of fluidsseparation of fluids
Source: Wikipedia
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Application: EnergyApplication: Energy
Increasing the efficiency of energyIncreasing the efficiency of energyproductionproduction
Increasing the efficiency of light conversionIncreasing the efficiency of light conversionthrough the use of nanostructuresthrough the use of nanostructures
Improving combustion by designing specificImproving combustion by designing specific
catalysts with maximized surface area. Specialcatalysts with maximized surface area. Specialshaped nanoparticles can applied to a surfaceshaped nanoparticles can applied to a surfacetransform into a solar collectortransform into a solar collector
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Effects of size effectsEffects of size effects
Produce qualitatively newProduce qualitatively newbehaviorbehavior
If the size of a nanoscaleIf the size of a nanoscalestructure becomes less thatstructure becomes less thatthe characteristic lengththe characteristic lengthscale for scattering ofscale for scattering ofelectrons or phonons thiselectrons or phonons thiscan lead to qualitativelycan lead to qualitativelynew modes of transport fornew modes of transport forelectrical current /or heat.electrical current /or heat.
Explains the ballisticExplains the ballistictransport of current intransport of current innanotubes.nanotubes.
Source: G.Belle: Magneto-Optical Studiesof Quantum Wells and Superlattices
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Manipulation and coupling ofManipulation and coupling ofproperties at the nanoscaleproperties at the nanoscale
Semiconductor PropertiesSemiconductor Properties
The fundamental properties of nanoscaleThe fundamental properties of nanoscalesemiconductor structures can be dramatically alteredsemiconductor structures can be dramatically alteredby controlling their size and shape without changingby controlling their size and shape without changingtheir composition. When the electrons and holes intheir composition. When the electrons and holes insemiconductors are confined to dimensions less thensemiconductors are confined to dimensions less thentheir de Broglie wavelength (typically 1 to 30 nm)their de Broglie wavelength (typically 1 to 30 nm)quantum mechanical size effects appear. The carrierquantum mechanical size effects appear. The carrier
confinement can be in one dimension (quantumconfinement can be in one dimension (quantumfilms or quantum wells), two dimensions (quantumfilms or quantum wells), two dimensions (quantumwires), or three dimensions (quantum dots, QDs, orwires), or three dimensions (quantum dots, QDs, ornanocrystals).nanocrystals).
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Effects of size effectsEffects of size effects
Systems with component sizes ranging from a fewSystems with component sizes ranging from a fewtenths to about ten nanometers lie at the fuzzytenths to about ten nanometers lie at the fuzzyboundary between the quantum and the classicalboundary between the quantum and the classicaldomains. Such systems are also in the size rangedomains. Such systems are also in the size range
where thermal energy fluctuations and Brownianwhere thermal energy fluctuations and Brownianmotion can have significant effects.motion can have significant effects.
Ultra thin films (a few atomic layers) yield quasiUltra thin films (a few atomic layers) yield quasi--
two dimensional magnetic material, reveal noveltwo dimensional magnetic material, reveal novelmagnetic domain physics, and provide a fascinatingmagnetic domain physics, and provide a fascinatingarena for studying the gradual onset of magnetism.arena for studying the gradual onset of magnetism.
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Effects of size effectsEffects of size effects
The mechanical properties of materials changeThe mechanical properties of materials changedramatically as the grain size in polycrystallinedramatically as the grain size in polycrystallinematerials or the concentration of strain fieldsmaterials or the concentration of strain fieldsapproaches the nanometer scaleapproaches the nanometer scale
Modes of failures will also change, as the scale ofModes of failures will also change, as the scale ofdevices and machines decreases toward thedevices and machines decreases toward thenanoscale.nanoscale.
The causes include different mechanical propertiesThe causes include different mechanical propertiesthat will modify fracture characteristicsthat will modify fracture characteristics increased importance of surface tensionincreased importance of surface tension
enhanced role of diffusion and corrosion at the largeenhanced role of diffusion and corrosion at the largesurfacesurface-- to volume ratios.to volume ratios.
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Modeling and simulationModeling and simulation
Great need for theory, modeling, and large scale computerGreat need for theory, modeling, and large scale computersimulationsimulation
Links between the electronic, optical, mechanical andLinks between the electronic, optical, mechanical andmagnetic properties of nanostructures and their size, shape,magnetic properties of nanostructures and their size, shape,topology, and composition are not well understood, althoughtopology, and composition are not well understood, although
for the simplest semiconductor systems, carbon nanotubes,for the simplest semiconductor systems, carbon nanotubes,and similar systems there has been considerable progress.and similar systems there has been considerable progress.
In nanoscale systems, thermal energy are comparable to theIn nanoscale systems, thermal energy are comparable to theactivation energy scale of the materials and devices, so thatactivation energy scale of the materials and devices, so that
statistical and thermodynamic methods must include thisstatistical and thermodynamic methods must include thiseffects adequately.effects adequately.
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Magnetic PropertiesMagnetic Properties
Dramatic quantization and other effects alsoDramatic quantization and other effects alsooccur in magnetism and magnetic materialsoccur in magnetism and magnetic materials
at the nanoscale.at the nanoscale.
Magnetic nanostructures grown withMagnetic nanostructures grown with
Molecular BeamMolecular Beam EpitaxieEpitaxie
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Thermal propertiesThermal properties
Polycrystalline materials exhibit lower thermalPolycrystalline materials exhibit lower thermalconductivity than lowconductivity than low--defect single crystals of thedefect single crystals of thesame material.same material.
This could result in significantly reduced thermalThis could result in significantly reduced thermalconductivities in nanostructured materials leadingconductivities in nanostructured materials leadingto improvements for applications such as thermalto improvements for applications such as thermalbarrier coatings.barrier coatings.
No detailed understanding of nanostructure thermalNo detailed understanding of nanostructure thermalproperties relationships until now.properties relationships until now.
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Thermal propertiesThermal properties
increasing thermal transport rates in fluids byincreasing thermal transport rates in fluids bysuspendingsuspending nanocrystallinenanocrystalline particles in them.particles in them.
NanofluidsNanofluids have recently been shown to exhibithave recently been shown to exhibitsubstantially increased thermal conductivities andsubstantially increased thermal conductivities andheat transfer rates compared to fluids that do notheat transfer rates compared to fluids that do notcontain suspended particles.contain suspended particles.
Up to now, there is no real understanding ofUp to now, there is no real understanding ofmechanisms by whichmechanisms by which nanoparticlesnanoparticles alter thermalalter thermal
transport in liquids.transport in liquids.
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Controlled Synthesis andControlled Synthesis andprocessing at the nanoscaleprocessing at the nanoscale
Current: NanometerCurrent: Nanometer--size objects are much largersize objects are much largerentities, with thousands or even millions of atoms inentities, with thousands or even millions of atoms inthem.them.
Need: Develop methods to prepare macroscopicNeed: Develop methods to prepare macroscopicquantities of nanoscale components in complexquantities of nanoscale components in complexdesigned patterns, using techniques of selfdesigned patterns, using techniques of selfassembly.assembly.
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Issues to be considered:Issues to be considered:
Manufacturing procedures to build tomorrowsManufacturing procedures to build tomorrowsnanonano--machines beyond the current and immediatemachines beyond the current and immediatefuture siliconfuture silicon--based fabrication technologybased fabrication technology
Property characterization (thermal, mechanical,Property characterization (thermal, mechanical,optical, chemical, biological) at the nanoscaleoptical, chemical, biological) at the nanoscale
Modeling of the complex behavior of extremely tinyModeling of the complex behavior of extremely tinydevices at the fundamental moleculardevices at the fundamental molecular--microscopicmicroscopic
components and assembly levelscomponents and assembly levels
Innovative control methods for NanosystemsInnovative control methods for Nanosystems
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Issues to be considered:Issues to be considered:
Friction, lubrication, cracking, failure analysis andFriction, lubrication, cracking, failure analysis andnondestructive testing in a nano worldnondestructive testing in a nano world
Innovative solutions for energy redistribution,Innovative solutions for energy redistribution,powering and actuation of the nanopowering and actuation of the nano--machinesmachines
Infrastructure for testing procedures suitable forInfrastructure for testing procedures suitable fornanodevicesnanodevices
Diagnostics and manipulation of nanoDiagnostics and manipulation of nano--systems forsystems forusage, environments consideration and ability tousage, environments consideration and ability tocontact larger systems from thecontact larger systems from the nanocomponentsnanocomponents
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Photonic CrystalsPhotonic Crystals
Have emerged as uniqueHave emerged as unique
structures with thestructures with thecapability to manipulate thecapability to manipulate theflow of light energyflow of light energy
To create photonic crystalsTo create photonic crystals
operating at opticaloperating at opticalwavelength the smallestwavelength the smallestfeature size must be of thefeature size must be of theorder of 100nmorder of 100nm
Source: Wikipedia
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NanotubesNanotubes
Nanotubes showNanotubes showtremendous promisetremendous promiseas building blocks foras building blocks fornew materials.new materials.
Due to their topology,Due to their topology,they do not exhibitthey do not exhibitsurface effects.surface effects.
Exhibit nearly idealExhibit nearly idealelectrical, optical, andelectrical, optical, andmechanical propertiesmechanical properties
Source: Wikipedia
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NanotubesNanotubes
Carbon nanotubes (Carbon nanotubes (CNTsCNTs) are allotropes of carbon) are allotropes of carbon
Members of the fullerene structural familyMembers of the fullerene structural family
Cylindrical shapeCylindrical shape
Diameter of a few nanometers (1/50,000Diameter of a few nanometers (1/50,000thth of theof thewidth of a hairwidth of a hair
The length to diameter ratio exceeds 1,000,000The length to diameter ratio exceeds 1,000,000
This results in novel properties: extraordinaryThis results in novel properties: extraordinarystrength, unique electrical properties, efficient heatstrength, unique electrical properties, efficient heatconductorconductor
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NanotubesNanotubes
The bonding structure is stronger than inThe bonding structure is stronger than indiamonddiamond
They align themselves into a ropeThey align themselves into a rope
structure and can merge together understructure and can merge together underhigh pressurehigh pressure
Specific strength of up to 48,000kNm/kg isSpecific strength of up to 48,000kNm/kg isthe best of known materials. High carbonthe best of known materials. High carbonsteel has only 154kNm/kgsteel has only 154kNm/kg
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NanotubesNanotubes
Multiple concentric nanotubes nested withinMultiple concentric nanotubes nested withinone another, exhibit a telescoping property.one another, exhibit a telescoping property.
An innerAn inner nanotubenanotube can slide almost withoutcan slide almost without
friction within its outerfriction within its outer nanotubenanotube shellshellcreating a perfect linear or rotationalcreating a perfect linear or rotational
bearing.bearing.
This property was used to create the worldsThis property was used to create the worlds
smallest rotational motor.smallest rotational motor.
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NanotubesNanotubes
The symmetry and electronic structure ofThe symmetry and electronic structure ofgraphenegraphene allows theallows the nanotubenanotube to eitherto either
have the characteristics of a metal or ahave the characteristics of a metal or a
semiconductor.semiconductor. Metallic nanotubes can have a currentMetallic nanotubes can have a current
density more than 1,000 times greater thandensity more than 1,000 times greater than
silver or copper.silver or copper. Highly toxic. Accumulate in the cytoplasm ofHighly toxic. Accumulate in the cytoplasm of
a cell and cause cell death.a cell and cause cell death.
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Nanosystems EngineeringNanosystems Engineering
Modeling the systems architectureModeling the systems architecture
ComplexityComplexity
ConstraintsConstraints
The environment and boundaries of theThe environment and boundaries of the
systemsystem
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Nanosystems EngineeringNanosystems Engineering
Modeling the systems architectureModeling the systems architecture
Account for computational and physicalAccount for computational and physicalconsiderationsconsiderations
Use technology independent models, based onUse technology independent models, based onuniversal considerations such as information,universal considerations such as information,energy entropy, etc. for generality of results.energy entropy, etc. for generality of results.
Integrated approachIntegrated approach
Models that encompass the physical constraintsModels that encompass the physical constraints
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Modeling the systems architectureModeling the systems architecture
The Device ModelThe Device Model
Model for the lowest functional component of the systemModel for the lowest functional component of the system
In conventional circuits: transistors, wires..In conventional circuits: transistors, wires..
In Nanotechnology: quantum dot,In Nanotechnology: quantum dot, nanotubenanotube laser etc.laser etc.
Device types have different shapes and sizesDevice types have different shapes and sizes Frank divides the device into coding and nonFrank divides the device into coding and non--codingcoding
subsystems.subsystems.
Coding subsystem is the part that is varied to encodeCoding subsystem is the part that is varied to encodedigital data or timing information. It consist of the logicaldigital data or timing information. It consist of the logical
subsystem (the actual data of interest) and thesubsystem (the actual data of interest) and theredundancy subsystem (noise, error detection)redundancy subsystem (noise, error detection)
NonNon--coding subsystem consists of structural and thermalcoding subsystem consists of structural and thermalsubsystemssubsystems
Reference: Michael P. Frank, Nanocomputer Systems Engineering
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Modeling the systems architectureModeling the systems architecture
Technology Scaling ModelTechnology Scaling Model Describes change of performance characteristics withDescribes change of performance characteristics with
change of sizechange of size
Interconnection ModelInterconnection Model
Describes how information is communicated between theDescribes how information is communicated between thelogical devices of the systemlogical devices of the system
Includes for example simple wiresIncludes for example simple wires
Timing ModelTiming Model Specifies how operations are synchronized in timeSpecifies how operations are synchronized in time
In Franks model timing signals are carried byIn Franks model timing signals are carried byinterconnects which can be treated as devicesinterconnects which can be treated as devices
Reference: Michael P. Frank, Nanocomputer Systems Engineering
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Modeling the systems architectureModeling the systems architecture
Architectural ModelArchitectural Model Specifies how the logical functions of the system areSpecifies how the logical functions of the system areorganizedorganized
Capacity Scaling ModelCapacity Scaling Model Frank uses the capacity scaling model to specify how theFrank uses the capacity scaling model to specify how the
capacity of the system can be scaled up to handle largercapacity of the system can be scaled up to handle larger
problems and how system performance scales as aproblems and how system performance scales as a
consequence.consequence.
Reference: Michael P. Frank, Nanocomputer Systems Engineering
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Modeling the systems architectureModeling the systems architecture
Energy Transfer ModelEnergy Transfer Model Accounts for the flow of energy and entropy through theAccounts for the flow of energy and entropy through thesystemsystem
Programming ModelProgramming Model
Specifies how the system is to be programmed to carrySpecifies how the system is to be programmed to carry
out desired functionsout desired functions
Error Handling ModelError Handling Model
Specifies how errors that accumulate in the system stateSpecifies how errors that accumulate in the system state
are detected and corrected. It includes mechanisms forare detected and corrected. It includes mechanisms for
noise immunity and error correction.noise immunity and error correction.
Reference: Michael P. Frank, Nanocomputer Systems Engineering
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Modeling the systems architectureModeling the systems architecture
Performance ModelPerformance Model Accounts for all constraintsAccounts for all constraints
Cost ModelCost Model
Cost are associate with manufacturing, and energyCost are associate with manufacturing, and energydissipationdissipation
Reference: Michael P. Frank, Nanocomputer Systems Engineering
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Nanosystems EngineeringNanosystems Engineering
ComplexityComplexity
High complexity because of size effectsHigh complexity because of size effects
Strong interdependencies:Strong interdependencies: Logical and thermal considerations which areLogical and thermal considerations which are
important for the efficiency of the encoding of digitalimportant for the efficiency of the encoding of digitalinformationinformation
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Nanosystems EngineeringNanosystems Engineering
ComplexityComplexity
Temperature and clock rate:Temperature and clock rate:
Increasing clock speed requires increasing deviceIncreasing clock speed requires increasing device
temperature requiring additional isolation of the hottertemperature requiring additional isolation of the hotterdevices from their cooler environment.devices from their cooler environment.
Information Propagation Speed:Information Propagation Speed:
Limited to the speed of light. Communication can thereforeLimited to the speed of light. Communication can thereforeonly be improved by packing devices closer together.only be improved by packing devices closer together.
Thermodynamic reasons prevent the reduction of theThermodynamic reasons prevent the reduction of the
devices size beyond a certain point.devices size beyond a certain point.
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Nanosystems EngineeringNanosystems Engineering
Constraints and challengesConstraints and challenges SizeSize
ThermalThermal
ManufacturingManufacturing
VerificationVerification
Environmental ImpactEnvironmental Impact
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Nanosystems EngineeringNanosystems Engineering
The environment and boundaries ofThe environment and boundaries ofthe systemthe system
How do we define the environment of theHow do we define the environment of thesystem and the system boundaries?system and the system boundaries?
ConcernsConcerns
ToxicityToxicity
Military Use and Ethics (Military Use and Ethics (NanoethicsNanoethics))
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ConclusionConclusion
The implementation of Nanosystems requires theThe implementation of Nanosystems requires the
analysis and modeling of complex systems withanalysis and modeling of complex systems withmany unknown parameters.many unknown parameters.
The system boundaries are not clearly defined.The system boundaries are not clearly defined.
The environmental impact will require systemsThe environmental impact will require systems
thinkers to find outthinkers to find out--of the box solutions forof the box solutions for
problems they have never anticipated.problems they have never anticipated.