Transcript Introduction to Machine Intelligence

Neuroprosthetics
Week 9
Emerging Technologies
Emerging Technologies
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Neurotechnology:Microelectronics
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Molecular and Nanoscale electronics
Microelectromechanical Systems
(MEMS)
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Goals and Requirements
Reduce/Eliminate interconnecting leads
Distribute intelligence
Minimize power consumption
Minimize device area (volume)
Improve reliability and longevity of implants
Molecular Electronics
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Molecular materials for electronics –
electronic devices using organic
compounds e.g. liquid crystal displays
Molecular scale electronics – size reduction
in individual processing elements
Molecular Materials
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Plastic Electronics
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Organic light-emitting structures
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Chemical sensors
Plastic Electronics
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Organic semiconductors low cost
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New materials with different bandgaps
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Simple fabrication for polymers
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Organic thin-film transistors key for plastic
circuitry as display drivers in computers,
as memory elements and ID tags
Organic Light-Emitting Structures
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Organic Light Emitting Devices (OLEDs) based on
polymer p-phenylene vinylene (PPV)
Organic semiconductor sandwiched between low
and high electrodes – when voltage applied,
electrons are injected from one electrode and holes
from the other
Recombination – light emission
Low molecular weight organic molecules and
polymers
Chemical Sensors
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Growing need for identification of chemical
& biochemical substances
Usually (Oxide) sensors must be operated
at high temperatures
Organic substances – high sensitivity to gas
Can be tailored to an application by
modification of their structure
Array of sensors (electronic nose) to
improve on sensitivity
Molecular Scale Electronics
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Molecular superlattices
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Single electron devices
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DNA electronics
Molecular Superlattices
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Pyroelectric devices good as detectors of
infrared – efficient at ambient temps.
Pyroelectric – noncentrosymmetric crystal
structure + thin-film fabricated
Grow thin polycrystalline film (ceramic)
then apply large electric field – RF
Sequential layer build up enables unique
polar structure
Single Electron Devices
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Current flow determined by tunnelling
through energy barriers
Structures of less than 10nm
Nanoparticles form FET – by sensing
current difference between 2 states so the
stored information can be read
Quantum effects become important
(Quantum computing)
DNA Electronics
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DNA deemed to be a molecular wire of very
small resistance
DNA – most significant molecule in nature!
Charge carriers can shuttle (tunnel) along a DNA
molecule for a few nm
DNA chips – short strands of DNA bind to others
– can probe if certain genetic codes are present
or absent
Data can be stored - DNA 1 bit in 1 nm3
DRAM 1 bit in 1000000000000 nm3
Final Words
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Organic compounds attractive for
electronic devices
Living systems assemble themselves from
molecules – energy efficient
But extremely speculative at this stage
Most likely niche areas – infrared detection
for example