2 August 2007 Jon Brame

A SWNT based Nanocompass for High Spatial Resolution

Magnetometry

Jon Brame, Johnathan Goodsell

Presented by Bryan Hicks

Brigham Young University

NASA GSFC Code 541

ESMD Student-Faculty Program

2 August 2007 Jon Brame

Overview

1. Project Motivation and Goal

2. Fabrication Process

3. Outcomes

2 August 2007 Jon Brame

CNT Properties• Change in Conductivity with Strain

– Tombler, et al

(Nature, 2000)– Single tube

2 August 2007 Jon Brame

CNT Properties• Change in Conductivity with Strain

– Tombler, et al

(Nature, 2000)– Single tube

2 August 2007 Jon Brame

Motivation

• Space Magnetometry– Spacecraft Orientation– Magnetic Field Studies

• Planetary Exploration– Astronaut/Rover

Orientation– Planetary Geology

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Device Operation

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Prototype

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Process: Catalyst

• Indirect Iron Catalyst Deposition

Vacuum Chamber for Thin Film Deposition

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Process: SWCNT Growth

• Chemical Vapor Deposition (CVD) SWCNT Growth

CVD Growth Furnace

Diagram of CVD Growth Process

SEM Image of SWCNT Mat

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Process – Electrical Contact

• Gold Contact Pads– Detector Development Lab (DDL)– E-Beam Lithography– Deposition: Chrome(100Å)-

Gold(1000Å)– Lift-off

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Process – Iron Needle

• Iron Needle– Device Alignment– E-Beam Lithography pattern– Deposition: Chrome-Iron-

Chrome– Lift-off

Diagram of SWCNT network, contact pads and iron needle

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Process – Trench• Lithography

(manual)

• Etching– Buffered

Oxide Etch– KOHDiagram of completed device

Au

Au

SWCNTs

Remnantneedle

Trench

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Results

• Completed Magnetometer Prototype

Successfully etched trench with SWCNT spanning gap between gold electrodes

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Results

• Magnetic Field Measurement Testing

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Outcome: BYU Collaboration

• Growth at BYU

• Clean Room Class

• Refinement of Growth Process

• Photomasks for Rapid Device Fabrication

Growth results reproduced at BYU. (approx mag=50Kx)

2 August 2007 Jon Brame

Acknowledgements

• Dr. Stephanie Getty and NASA Goddard Space Flight Center code 541

• Dr. David Allred: BYU Physics Dept.• Bryan Hicks, Rachel Bis, Melissa Harrison• Branch 541: Dewey Dove, Bruno Munoz, Carl Taylor,

Len Wang• Division 540; Dick Fahey; Joshua Halpern; ESMD;

Rocky Mountain Space Grant Consortium • BYU: Dr. Richard VanFleet, Dr. Jeffrey Farrer, Dr.

Robert Davis, David Hutchinson• Other: Lynda Goodsell, Bill Heaps