Molecular ElectronicsSlide 2Why Molecular Electronics?Can Molecular Electronics Be Better?Recent ResearchRecent Research cont.Self AssemblyForming 3-D Electrical Networks by Self AssemblyHow Does this Relate to Molecular Electronics?Present and Future ApplicationsDNAPossible Uses for DNA in MicroelectronicsDNA SET TransistorFunctionalization of NanoparticlesCellular Computing: GoalsQMC’sTMC’sCells and Human-Made ComputersCells vs. Human Made ComputersCells vs. Human Made Computers 2Questions?Molecular ElectronicsMolecular ElectronicsEnma 465Enma 465May 14, 2003May 14, 2003ByByCharles BrooksCharles BrooksMark Hanna Mark Hanna Chen Kung Chen Kung Jia NiJia NiMolecular ElectronicsMolecular ElectronicsDefinition – is a field emerging around the premise that Definition – is a field emerging around the premise that it is possible to build individual molecules that can it is possible to build individual molecules that can perform functions identical to those of the key perform functions identical to those of the key components of today’s microcircuits.components of today’s microcircuits.Source: Reed. www.scientificamerican.comWhy Molecular Electronics?Why Molecular Electronics?Chip-fabrication specialists will find it Chip-fabrication specialists will find it economically infeasible to continue scaling economically infeasible to continue scaling down microelectronics. down microelectronics. stray signals on the chipstray signals on the chipthe need to dissipate the heat from so many closely the need to dissipate the heat from so many closely packed devicespacked devicesthe difficulty of creating the devices in the first the difficulty of creating the devices in the first placeplaceCan Molecular Electronics Can Molecular Electronics Be Better?Be Better? Modern technologies can only go so far.Modern technologies can only go so far.Solution (new development)Solution (new development)DNA - It is promising to achieve super-high DNA - It is promising to achieve super-high density memory and high sensitive detection density memory and high sensitive detection technology.technology.Cell ComputingCell ComputingSilicon transistors at 120 nm in length will still Silicon transistors at 120 nm in length will still be 60,000 times larger in area than molecular be 60,000 times larger in area than molecular electronic devices.electronic devices.Recent ResearchRecent ResearchRecent studies have shown that individual molecules Recent studies have shown that individual molecules can conduct and switch electric current and store can conduct and switch electric current and store information.information.July of 1999 – HP and the University of California at July of 1999 – HP and the University of California at Los Angeles build an electronic switch consisting of a Los Angeles build an electronic switch consisting of a layer of several million molecules of an organic layer of several million molecules of an organic substance called rotaxane.substance called rotaxane.Linking a number of switches - a version of an AND gate is Linking a number of switches - a version of an AND gate is produced.produced.Recent Research cont.Recent Research cont.June 2002 - Fuji Xerox biotechnology made a June 2002 - Fuji Xerox biotechnology made a prototype transistor of DNA from salmon prototype transistor of DNA from salmon sperm.sperm.Researchers successfully passed an electric current Researchers successfully passed an electric current through the DNA-transistor.through the DNA-transistor.This demonstrates that the chain behaves in a This demonstrates that the chain behaves in a similar fashion to semiconductor.similar fashion to semiconductor.Super smaller chip in 10 years.Super smaller chip in 10 years.Self AssemblySelf AssemblyMolecular self-assembly:Molecular self-assembly:the autonomous organization of components into the autonomous organization of components into patterns or structures without human intervention patterns or structures without human intervention (Whitesides 2002)(Whitesides 2002)Current Problem: Forming electrical interconnects Current Problem: Forming electrical interconnects between moleculesbetween moleculesSource: Reed. www.scientificamerican.comForming 3-D Electrical Networks by Forming 3-D Electrical Networks by Self AssemblySelf AssemblyBasic unit is a polyhedron on whose faces Basic unit is a polyhedron on whose faces electrical circuits are printed electrical circuits are printed LEDs wired to patterns of solder dots on LEDs wired to patterns of solder dots on adjacent faces of the polyhedron adjacent faces of the polyhedron Suspend in an isodense liquid as they come Suspend in an isodense liquid as they come into contact with one another into contact with one another Drops of molten solder fuse, assembling into Drops of molten solder fuse, assembling into regular structures regular structures Source: Gracias 2000Gracias 2000How Does this Relate to Molecular How Does this Relate to Molecular Electronics?Electronics?self-assembly originated in the study of self-assembly originated in the study of moleculemolecules, it is a strategy applicable at all s, it is a strategy applicable at all scales scales By examining polyhedra self assembly we can By examining polyhedra self assembly we can begin to understand how we can self assemble begin to understand how we can self assemble molecules with electrical interconnectsmolecules with electrical interconnectsPresent and Future ApplicationsPresent and Future ApplicationsRobotics and Manufacturing Robotics and Manufacturing components become smaller and conventional components become smaller and conventional robotic methods will fail. robotic methods will fail. Self-assembly offers a new approach to the Self-assembly offers a new approach to the assembly of parts with nanometer dimensions. assembly of parts with nanometer dimensions. Microelectronics Microelectronics Self-assembly offers a possible route to three-Self-assembly offers a possible route to three-dimensional microsystems dimensional microsystemsDNADNAWell known from biologyWell known from biologyForms predictable structureForms predictable structureControllable self assembly Controllable self assembly through base pair sequencesthrough base pair sequencesMay be selectively processed May be selectively processed using restriction enzymesusing restriction enzymesSource: