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M. Meyyappan Director, Center for Nanotechnology NASA Ames Research Center Moffett Field, CA 94035 meyya@orbit.arc.nasa.gov web: http://www.ipt.arc.nasa.gov • Advanced miniaturization, a key thrust area to enable new science and exploration missions - Ultrasmall sensors, power sources, communication, navigation, and propulsion systems with very low mass, volume and power consumption are needed • Revolutions in electronics and computing will allow reconfigurable, autonomous, “thinking” spacecraft • Nanotechnology presents a whole new spectrum of opportunities to build device components and systems for entirely new space architectures - Networks of ultrasmall probes on planetary surfaces - Micro-rovers that drive, hop, fly, and burrow - Collection of microspacecraft making a variety of measurements Europa Submarine * Carbon Nanotubes • Growth (CVD, PECVD) • Characterization • AFM tips Metrology Imaging of Mars Analog Imaging Bio samples • Electrode development • Biosensor (cancer diagnostics) • Chemical sensor • Logic Circuits • Chemical functionalization • Gas Absorption • Device Fabrication * Molecular Electronics • Synthesis of organic molecules • Characterization • Device fabrication * Genomics • Nanopores in gene sequencing • Genechips development * Computational Nanotechnology • • • • • • • • • • CNT - Mechanical, thermal properties CNT - Electronic properties CNT based devices: physics, design CNT based composites, BN nanotubes CNT based sensors DNA transport Transport in nanopores Nanowires: transport, thermoelectric effect Transport: molecular electronics Protein nanotube chemistry * Quantum Computing * Computational Quantum Electronics • Noneq. Green’s Function based Device Simulator * Inorganic Nanowires * Protein Nanotubes * Computational Optoelectronics • Synthesis • Purification • Application Development * Computational Process Modeling • • • • • • Nanoelectronics (CNTs, molecular electronics) Non-CMOS circuits and architectures, reconfigurable systems Spintronics, quantum computing, nanomagnetics Nanophotonics, nano-optics, nanoscale lasers…. Chemical and biological sensors Novel materials for all applications (CNTs, quantum dots, inorganic nanowires… • Integration of nano-micro-macro • Bio-nano fusion • • • • Carbon Nanotubes - CNT - growth and characterization - CNT based nanoelectronics - CNT based microscopy - CNT interconnects - CNT based biosensors - CNT chemical sensors • Some other Nano examples - Inorganic nanowires - Protein nanotubes - Nano in gene sequencing CNT is a tubular form of carbon with diameter as small as 1 nm. Length: few nm to microns. CNT is configurationally equivalent to a two dimensional graphene sheet rolled into a tube. CNT exhibits extraordinary mechanical properties: Young’s modulus over 1 Tera Pascal, as stiff as diamond, and tensile strength ~ 200 GPa. CNT can be metallic or semiconducting, depending on chirality. • The strongest and most flexible molecular material because of C-C covalent bonding and seamless hexagonal network architecture • Young’s modulus of over 1 TPa vs 70 GPa for Aluminum, 700 GPA for C-fiber - strength to weight ratio 500 time > for Al; similar improvements over steel and titanium; one order of magnitude improvement over graphite/epoxy • Maximum strain ~10% much higher than any material • Thermal conductivity ~ 3000 W/mK in the axial direction with small values in the radial direction • Electrical conductivity six orders of magnitude higher than copper • Can be metallic or semiconducting depending on chirality - ‘tunable’ bandgap - electronic properties can be tailored through application of external magnetic field, application of mechanical deformation… • Very high current carrying capacity • Excellent field emitter; high aspect ratio and small tip radius of curvature are ideal for field emission • Can be functionalized • CNT quantum wire interconnects • Diodes and transistors for computing • Capacitors • Data Storage • Field emitters for instrumentation • Flat panel displays • THz oscillators Challenges • • • • Control of diameter, chirality Doping, contacts Novel architectures (not CMOS based!) Development of inexpensive manufacturing processes • High strength composites • Cables, tethers, beams • Multifunctional materials • Functionalize and use as polymer back bone - plastics with enhanced properties like “blow molded steel” • Heat exchangers, radiators, thermal barriers, cryotanks • Radiation shielding • Filter membranes, supports • Body armor, space suits Challenges - Control of properties, characterization - Dispersion of CNT homogeneously in host materials - Large scale production - Application development