Java Software Solutions Foundations of Program Design

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Pulsed Laser Deposition for Fabrication of
Nanostructures Kai Dou Department of
Physics Tel [phone] Email
dou_at_okstate.edu Office 205 PSI PLD Lab 020 NRC
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• PLD Chracteristics
• Reproduce the composition of the target
• Fabricate multicomponent multilayer structures
• Fast response and well controlled deposition rate
• Environmentally benign technique
• Diversity of materials and device structures
• NPs waveguide
• HR Coating
• Nanomaterials and Biological Samples
• Fullerene
• Porphyrin
• Polymer nanoparticles

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Pulsed Laser Deposition (PLD) Processes
(B)
(A)
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• MBE-Molecular Beam Epitaxy

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Plume Generated by Laser Ablation With Different
Tiny or Micro-Particles
Atoms Molecules Ions Electrons
Holes Plasma Clusters Particulates
Laser Beam
Target
Plume
Substrate
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Transient Plume Development with and without
Reaction Gas
10-6 Torr
100 mTorr O2
D. Geohegan, Appl. Phys. Lett. 60, 2732 (1992)
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Pulsed Laser Deposition (PLD) System- Excimer
Laser and Chamber
View Windows
Laser
Chamber
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Pulsed Laser Deposition SystemLaser, Chamber,
and Controller
Chamber
Laser
Controller
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Pulsed Laser Deposition (PLD) System- Excimer
Laser and Chamber
Motors
10 inch
Laser
Holder
Glass Dome
Motors
Target
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Scale-Up PLD for Large Substrate Coating
Two Targets
Cylindrical Lens
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1D HR PC Structure

• 1D Photonic Structure

Low n CaF2 MgF2 High n Zr2O3 TiO2 ZnS
Quarter Wave Stack for HR
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• 2D Photonic Structure

J. Joannopoulos, 1995
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3D Photonic Structure
S. Romanov, 1998
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NPs ZnSMn Wave Guides TiO2-PPV
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Ablation Mechanism for Semiconductors
CB
CB
donor
Deep level
Egap
TP
SP
acceptor
VB
VB
Pure Semicond.
Doped Semicond.
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Ablation Mechanism for Organic Molecules
Physical Ablation Mechanism
Direct ablation E(laser) gt EZP Couple into
vibration E(laser) hw/2p Molecules as
dopant absorbing E(laser) Tailored groups
enhancing absorption