TECHNICAL SEMINAR ON TECHNOLOGIES AND DESIGNS FOR ELECTRONIC NANOCOMPUTERS

1. TECHNICAL SEMINAR ON TECHNOLOGIES AND DESIGNS FOR ELECTRONIC NANOCOMPUTERS PRESENTED BY :BIJAY KUMAR XESS ADMN NO :4 I&E/2K

4. Genesis of Nanotechnology. A timeline of selected key events plotted versus time with Moore’s Law trend line.

6. FUTURE TECHNOLOGIES : LIKELY APPROACHES TO • NANOELECTRONIC TWO STATE DEVICES • RESONANT TUNNELING TRANSISTOR • SINGLE-ELECTRON TRANSISTOR • ELECTROSTATIC QUANTUM DOT CELLS • MOLECULAR SHUTTLE SWITCH • 5. ATOM RELAY • 6. REFINED MOLECULAR RELAY

8. CONDUCTANCE PEAK OF AN RTD RESONANT TUNNELING TRANSISTOR

9. SCHEMATIC OF A RESONANT-TUNNELING DIODE (RTD)

10. Single Electron Transistor Concept of a Quantum Dot

12. Emerging technologies for the implementation of Nanoelectronics • Molecular electronics • # Uses primarily covalently bonded molecular structures • # Molecules are nanometer-scale structures • # Three obstacles must be overcome to realize molecular electronics • # Potential increase in device density by a factor of as much as 10^7 i.e. 10 million • # Challenges that remain on the path to creating molecular electronic computational devices • # Potential advantages from a pursuit of molecular electronics • # Ultimate solution to the problem of economical fabrication of ultra dense, nanometer-scale • computer electronics • b. Silicon Nanoelectronics • # Si has a lower thermal conduction limit • # Electrons move faster in GaAs than in Si in low electric fields • # More reliability and uniformity in the processing of Si substrates • # More economical over time and ecologically safer for the environment • # A heterojunction is necessary to create a potential well or barrier , the basis for constructing a • solid state quantum effect device • # Tunnel barriers or heterolayers will also be needed to control leakage current in a nanometer-scale • Si based device

13. FABRICATION • LITHOGRAPHY • MOLECULAR BEAM EPITAXY (MBE) • MECHANOSYNTHESIS WITH NANOPROBES • CHEMOSYNTHESIS

14. REMAINING CHALLENGES FOR NANOELECTRONICS • Build logic structures or computers from nanometer-scale components • Devising and putting in place the infrastructure for manufacturing thousands or millions of • ULSI computers • Raise operational temperatures close to room temperature • Reliable, precision manufacture of such devices • Functioning logic structure must be demonstrated • Devices must be arranged and connected densely in units • Processes for error correction must be invented • 8. Conversion of research on small numbers of prototype nanodevices and nanocomputers to • practical and reliable mass produced systems

16. CONCLUSION -- New approaches to building computers are necessary to ensure technical progress at the current rate -- RTDs, Quantum dots or SETs should be attainable with next generation technology -- Smaller molecular electronic devices are likely to require further research -- Factors governing choice of technologies and designs – Device speed, power dissipation, Reliability, ease of fabrication -- Developments in molecular electronics may even race ahead of those in solid-state nanoelectronics

17. END OF THE SEMINAR THANK YOU