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Carbon Nanosheets and Carbon Nanotubes by RF PECVD W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 2006 Carbon nanosheets and carbon nanotubes by RF PECVD Mingyao Zhu College of William & Mary - Arts & Sciences Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Condensed Matter Physics Commons Recommended Citation Zhu, Mingyao, "Carbon nanosheets and carbon nanotubes by RF PECVD" (2006). Dissertations, Theses, and Masters Projects. Paper 1539623509. https://dx.doi.org/doi:10.21220/s2-bc4z-d393 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. CARBON NANOSHEETS AND CARBON NANOTUBES BY RF PECVD A Dissertation Presented to The Faculty of the Department of Physics The College of William and Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Doctor of Philosophy by Mingyao Zhu September, 2006 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPROVAL SHEET This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Mingyao Zhu Approved by the Committee, September 2006 Dennis M. Manos, Chair Brian C. Holloway ^ William J. Kossler Anne C. Rei (]/fitted? ' David W. Thompson f Department of Chemistry 11 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Dedicated to my parents and my husband iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Acknowledgements.........................................................................................................ix List of Tables ............................................................................................... x List of Figures..................................................................................................................xii Abstract........................................................................................................................... xxiv Chapter 1: Introduction.............................................................................. 2 1.1 Introduction to carbon nanostructures and PECVD ..................................................2 1.2 Organization of dissertation ........................................................................................6 Chapter 2: Characterization Tools for Carbon Nanostructure Material Analysis.................................................................... 11 2.1 Introduction ............................................................................................................... 11 2.2 Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS) ...................................................................................................12 2.3 Transmission electron microscopy (TEM) and Selected area diffraction (SAD)..........................................................................................................................14 2.4 Atomic force microscopy (AFM) ..............................................................................15 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2.5 Raman and FT-IR spectroscopy ................................................................................17 2.6 X-ray diffraction (XRD) ............................................................................................ 19 2.7 Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS)......................................................................................................................... 20 2.8 Particle induced X-ray emission (PIXE) and elastic recoiled detective analysis (ERDA) .........................................................................................................22 2.9 Four-point resistivity measurement .......................................................... 24 2.10 Other characterization methods for applied properties ..........................................26 2.10.1 Field emission (FE) measurement .................................................................26 2.10.2 Thermal desorption spectroscopy (TDS) ......................................................27 2.10.3 Brunauer-Emmett-Teller (BET) surface area measurement ...................... 28 2.11 Summary...................................................................................................................28 Chapter 3: RF PECVD System Design and Operation Modes.................. 44 3.1 Introduction ...............................................................................................................44 3.2 RF PECVD system setup ..........................................................................................47 3.2.1 RF PECVD system setup ............................................................................... 47 3.2.2 Matching network for RF PECV D .................................................................49 3.3 Plasma coupling modes and deposition conditions ................................................52 3.3.1 Inductive coupling m ode ................................................................................. 52 3.3.2 Capacitive coupling m ode ............................................................................... 53 Chapter 4: CNT Deposition and Properties...................................................... 62 4.1 Introduction of CNT synthesis ................................................................................. 62 4.2 Nanosphere lithography (NSL) for catalyst patterning ..........................................64 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 4.2.1 Introduction .......................................................................................................64 4.2.2 Single-layer and double-layer N SL .................................................................65 4.2.3 NSL for carbon nanotube catalyst patterning ................................................67 4.3 Deposition and characterization of CN T .................................................................69 4.3.1 Structure and properties of typical C N T ........................................................ 69 4.3.2 CNT deposited under other conditions .......................................................... 70 4.4 Field emission of CNT-based, back-gated devices ................................................72 4.5 Sum m ary ................................................................................................................... 73 Chapter 5: Carbon Nanosheet: Experimental Deposition and Characterization....................................................................................90 5.1 Introduction of CNS synthesis ..................................................................................90 5.2 Deposition and properties of typical C N S .............................................................. 92 5.2.1 Typical CNS deposition ..................................................................................92 5.2.2 SEM and TEM of typical C N S .......................................................................92 5.2.3 AES and XPS of typical C N S .........................................................................94 5.2.4 PIXE, ERDA, and TDS of typical C N S ........................................................ 95 5.2.5 Raman and FTIR of typical CNS ...................................................................96 5.2.6 X-ray diffraction of typical CNS ...................................................................99 5.2.7 Field emission of typical CNS .....................................................................100 5.2.8 Four-point resistivity of typical C N S ................................................................ 102 5.2.9 BET surface area of typical C N S .................................................................104 5.3 Parametric study of carbon nanosheet grow th.......................................................105 5.3.1 Substrate temperature .................................................................................. 107 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 5.3.2 Methane concentration ..................................................................................108 5.3.3 Input RF pow er .............................................................................................. 109 5.3.4 Total gas pressure .......................................................................................... 110 5.4 Modification and application of carbon nanosheets ..............................................I ll 5.4.1 Aligned CNS deposition ................................................................................I l l 5.4.2 CNS from other gas compositions ...............................................................112 5.4.3 Metal coating on CNS for catalyst support .................................................. 114 5.4.4 Preliminary results of CNS-based, back-gated field emission devices ... 114 5.5 Sum m ary
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