Nanoparticle Devices

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Nanoparticle Devices

• S. A. Campbell, ECE
• C. B. Carter, CEMS
• H. Jacobs, ECE
• J. Kakalios, Phys.
• U. Kortshagen, ME

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Applications of nanoparticles
Vertical TransistorsNishigushi and Oda, J. Appl.
Phys. 88, 4186, 2000 .
Flash MemoryTiwari et al., Appl. Phys. Lett. 68,
1377, 1996.
Quantum PhosphorRowher et al., Sandia Natl.
Lab., 2003.
Silicon LaserCanham, Nature 408, 411, 2000.
Silicon LEDsPark et al., Appl. Phys. Lett., 78,
2575, 2001.
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The Vision Nanoparticle Transistors

• Vertical Schottky Barrier FET
• Does not require doping
• Can be built on any kind of substrate
• 3D integration
• Scales easily to very small size
• What is needed?

Single crystal, defect-free silicon nanoparticles
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Improved Solar Cells

• Light-induced defect creation (Staebler-Wronski
  effect) limits efficiency of solar cells.
• New materials appear promising

nanostructured silicon
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Uwe Kortshagen Silicon nanoparticles for
electronic devices Dept. of Mechanical Eng.

• Novel electronic devices such as vertical
  transistors
• Solid-state lighting silicon quantum dots as
  environmentally benign material
• More efficient solar cells with increased
  stability

2-nm silicon crystallite in amorphous silicon
matrix
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Uwe Kortshagen

• Nonthermal plasmas for silicon nanocrystals
• Design plasma properties for optimal particle
  properties

silicon particles forelectronic devices

• nanoparticles with 1 trap site / particle
• nonagglomerated silicon nanocrystals with narrow
  size distribution.

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Nanoparticles of Silicon
C. Barry Carter
Dept. of Ch. E. Materials Science

• Structure by high-resolution TEM
• Ceramics, semiconductors and metals

• Link to properties through collaborations
• The new HRTEM

TEM the essential tool for nanoparticle research
Shape of nanoparticles
Defects and surface reactions
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Devices and True Nanoparticles
C. Barry Carter
Crystal of Si in amorphous Si

• Link to Devices
• Morphology and Perfection
• Crystals in Amorphous Films
• Phase transformations

Stacking fault in a 2nm particle!
Students Chris Perrey Julia Deneen
Twin boundary in a 1.5nm particle!
The new HRTEM
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Jim Kakalios Opto-Electronic Properties of
Nanostructured Silicon Thin FilmsSchool of
Physics and Astronomy

• Thin Film PECVD Amorphous Silicon (a-SiH)
  Preferred for TFTs and Solar Cells
• Light-Induced Defect Creation Major Liability
• Silicon Nanocrystals Embedded Within Amorphous
  Silicon (a/nc-SiH) Resist Light-Induced
  Degradation

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Jim Kakalios

• TEM confirms nanocrystals in
• a/nc-SiH films
• Optical and Electrical Properties of
  Nanostructured Material Comparable to Best
  Quality a-SiH

• Light-Induced Decay of Photosensitivity (Ratio of
  Photo-to-Dark Conductivity) Reduced in a/nc-SiH
  Films

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Steve Campbell Nanoparticle DevicesElectrical
and Computer Engineering

• Limits to the scaling of planar CMOS in sight
• Possible new directions
• 3D integrated circuits
• Mixing electronics/optics /magnetics/etc. on the
  same chip
• Single crystal nanoparticles can be used for both
  purposes

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Steve Campbell

• Methods for making single crystal semiconductor
  nanoparticles
• Building and characterizing nanoparticle devices
• MSM structures
• Silicon transistors

• NP properties highly dependent on surface
• Good interfaces possible
• Outstanding performance expected due to low C

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Heiko O. Jacobs Self-Assembly of Nanoparticle
Building BlocksElectrical and Computer
Engineering Dept.

• Electrostatic interaction can be used to position
  5 nm - 50 mm sized components
• Sub-100 nm resolution has been accomplished
• Programmability will be possible using
  programmable electrodes/receptors

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Heiko O. Jacobs

• Parallel charge patterning by Electric
  Nanocontact Lithography
• Electrostatically driven self-assembly of
  nanoparticles from the liquid and gas phases

SWNT Rope bundle

• Developed a technique to pattern charge with 100
  nm resolution
• Developed a nanoxerographic printer to print
  nanoparticles with 60 nm resolution