What is Moletronics
• It is interdisciplinary theme that spans Physics ,
Chemistry & Material science.
• Special feature is the use of molecular building block for
fabrication of electronic component in both active and
• It is such field of nanoscience ,that evolves with the
exploration of the electronic level structure , response &
transport for development of electronic devices.
• As there is binding of molecular building block it forms
larger structure and show dynamical stereochemistry.
• Robert muliken & Albert Szent-Gyorgi proposed
study of charge transfer theory in1940.
• In 1974 Mark Ratner & Avi Aviram illustrated a
theoratical molecular rectifier.
• Later Avi Aviram detailed a single molecular field
effect transistor in1988.
• In 2000Shirakawa, Heeger and MacDiarmid won
Noble prize in physics for potentially high
conductivity of (oxidised) polyacetelene &
About Molecular Electronics
• The principle of above research is that biological
systems can give useful paradigm for developing
electronic and computational devices at the molecular
• The approach involves the design and synthesis of
dyads, triads and other super molecular species using
the techniques of organic chemistry.
• In order to studied newly prepared molecule time
resolved laser spectroscopy, NMR spectroscopy.
Why molecular electronics
• For electronic application, molecular structures
has four major advantages:
• Assembly & Recognition.
• Dynamical stereochemistry.
• Synthetic tailor ability.
• The number of transistors that can be fabricated
on a silicon integrated circuit--and therefore the
computing speed of such a circuit--is doubling
every 18 to 24 months.
• After four decades, solid-state microelectronics
has advanced to the point at which 100 million
transistors, with feature size measuring 180 nm
can be put onto a few square centimeters of
• The molecule electrode interface limit current
flow & completely modify the measured electrical
response of the junction.
• Poor covalent bonding exists between molecule
• A related consideration involves how chemical
nature of molecule-electrode affects the rest of
• The proposed circuit architectures have
attempted to deal with five key issues:
• Tolerance to manufacturing defects.
• Introduction to non-traditional fabrication
• scalability to near molecular dimensions.
• Briding between device densities.
• Fabrication symplicity.
Crossbars & Demultiplexers
• The most attractive architectures for designing
molecular-electronics circuits for computational
applications and interfacing them to the
macroscopic world is the crossbar.
• The memory, shown on the right, consists of two
major components. The central crossbar—the
crossing of16 vertical and 16 horizontal black
wires—constitutes a 256-bit memory circuit.
Figure of Crossbars and
Crossbars and Demultiplexers
• Low power consumption.
• Able to integrate large circuit
• Controlled fabrication with in specified
• Hard experimental verification.
• Molecular systems, or systems based on small
organic molecules, possess interesting and
useful electronic properties.
• The investigations of molecular systems that
have been performed in the past have been
• The potential application of molecular electronics
has already attracted the interest of some large