1. Week 9 Emerging Technologies
Neuroprosthetics
Week 9
Emerging Technologies

2. Emerging Technologies
Neurotechnology:Microelectronics
Molecular and Nanoscale electronics

3. Microelectromechanical Systems (MEMS)
Goals and Requirements
Reduce/Eliminate interconnecting leads
Distribute intelligence
Minimize power consumption
Minimize device area (volume)
Improve reliability and longevity of implants

4. Molecular Electronics
Molecular materials for electronics – electronic devices using organic compounds e.g. liquid crystal displays
Molecular scale electronics – size reduction in individual processing elements

5. Molecular Materials Plastic Electronics
Organic light-emitting structures
Chemical sensors

6. Plastic Electronics Organic semiconductors low cost
New materials with different bandgaps
Simple fabrication for polymers
Organic thin-film transistors key for plastic circuitry as display drivers in computers, as memory elements and ID tags

7. Organic Light-Emitting Structures
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

8. Chemical Sensors
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

9. Molecular Scale Electronics
Molecular superlattices
Single electron devices
DNA electronics

10. Molecular Superlattices
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

11. Single Electron Devices
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)

12. DNA Electronics
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 nm DRAM 1 bit in nm3

13. Final Words 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