March 4th , 2010
EML 4905 Senior Design Project
Advisor: Dr. K. H. Wu
March 24, 2010
Shamil Baldeosingh
Dasney Joseph
Walter McKinley
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Background
Problem Statement
Design Specifications
Conceptual Designs
Project Management
Future Plans
2
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Chemical Vapor Deposition ( CVD )
 Widely used for engineering applications
• Scalable to industrial production
• 20-100 % yield
• Controllable parameters to determine properties
3
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Large Research Interest
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Properties
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Mechanical
Electrical
Thermal
Novel Applications
Variations
• Dimensions and Geometry
• Quality and Yield
Zhao et al., Physical Review Letters,
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CNT synthesis for current CVD system
 3 hours for sample size of 1 – 5 grams
▪ Furnace heating of entire reaction chamber
▪ Such a large sample size is not necessary for research
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CNT synthesis for proposed CVD system
 0.5 hours for sample size of less than 1 gram
▪ Localized heating of gases and substrate
▪ Appropriate for research applications
5
Volumetric flow Rate
(mL/min)
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PROCESS GAS
Hydrogen (H2)
400
PRECURSOR GAS
Acetylene (C2H2)
100
CARRIER GAS
Argon (Ar)
600
Preheated Gas Temperature
• At least 400 ̊c
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Substrate Temperature
• 600-1000 ̊c
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Packaging
Accessibility
 Substrate should be easily loaded
 Maintenance of system
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Gas flow
 Reynolds number << 2100 : Laminar Flow
 Peclet number << 1
 Knudsen number > 1
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9
10
Excellent – 1
Very Good -2
Good – 3
Fair – 4
Poor - 5
Design A
Straight Tube
Design B
Variable Cross
Section Tube
Design C
Cube
Packaging
4
4
1
Accessibility
5
5
1
Gas Flow
3
2
4
Price
1
2
5
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Substrate Material
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Thermal Strength
• Thermal Shock
Wafer
Powder
• Thermal Expansion
• Deflection
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Resistive Heating
Element
• Material
• Configurations
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Power Input
•
AC vs. DC
• H-Current/ L-Voltage
• L-Voltage/H-Current
• Life span
12
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Heat Generation
 Dasney Joseph
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Instrumentation and Fluid Mechanics
 Shamil Baldeosingh
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Conceptual Designs and Prototype
 Walter McKinley
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Gantt Chart -Spring 2010
14
Gantt Chart - Fall 2010
15
January
February
March
April
TIME (hours)
25
20
15
10
5
0
SHAMIL
DASNEY
WALTER
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Design Modeling
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• SolidWorks
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Instrumentation and
Control
• LabVIEW
• Thermocouple
• Infrared Temperature
Simulation
• ANSYS CFX
▪ Fluid Mechanics
▪ Heat Transfer from Resistive
Heating Elements
Sensor
• Mass Flow Controller
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Prototype Testing
• Scanning Electron
Microscope ( SEM )
▪ Verify growth of CNT’s
17
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Dr. Wu ( Florida International University )
Amit Datye ( Oak Ridge National Laboratory )
John Hart ( Massachusetts Institute of Technology )
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