Nanomechanical and Nanoelectromechanical phenomena in 2D atomic crystals : a scanning probe microscopy approach

목차 (Table of Contents)

• CONTENTS
• 1 Introduction = 1
• References = 5
• 2 Background = 7
• 2.1 2D Materials = 7
• 2.1.1 Graphene = 7
• 2.1.2 Hexagonal Boron Nitride (h-BN) = 9
• 2.1.3 Molybdenum Disulphide MoS₂= 11
• 2.1.4 Optical Visibility of 2D Materials = 12
• 2.2 Nanoelectromechanical Systems (NEMS) from Graphene and Other 2D Materials = 14
• 2.2.1 Electrostatic Actuation of Graphene Resonator Devices = 15
• 2.2.2 Damping Mechanisms Present in 2D NEMS = 17
• 2.2.3 Beam-Membrane Mechanical Transition in 2D Materials = 19
• 2.2.4 Characterisation of NEMS Based on 2D Materials = 20
• 2.3 Investigating Sample Electrical and Mechanical Properties with SPM = 23
• 2.3.1 Cantilever Dynamics = 23
• 2.3.2 Mechanical Techniques = 24
• 2.3.3 Electrical Techniques = 26
• 2.3.4 Time-Resolved Techniques = 30
• References = 33
• 3 Materials and Methods = 37
• 3.1 2D Materials Preparation = 37
• 3.1.1 Substrate Preparation and Interaction = 37
• 3.1.2 Building Heterostructures; An All-Dry Transfer of 2D Materials = 37
• 3.1.3 Sample Degradation and Oxidation = 39
• 3.2 Scanning Probe Methods = 41
• 3.2.1 Sample Vibration = 41
• 3.2.2 Tip Vibration = 41
• 3.2.3 Electrostatic／Heterodyne Force Microscopy (HFM) = 42
• References = 43
• 4 Morphology of 2D Materials and Their Heterostructures = 45
• 4.1 Graphene on Hexagonal Boron Nitride = 45
• 4.2 Graphene on Hexagonal Boron Nitride: Moirè Pattern = 46
• 4.3 Summary = 51
• References = 51
• 5 Nanomechanical Phenomena = 53
• 5.1 Subsurface Imaging in 2D Materials with Ultrasonic Force Microscopy = 53
• 5.1.1 Theoretical Interpretation : Sample Anisotropy = 54
• 5.1.2 Observing Subsurface Structure in 2D Materials = 58
• 5.2 Mechanical Properties of Graphene Grown on 4H-SiC : Effects of Hydrogen Intercalation = 62
• 5.2.1 Stiffness Measurements of Graphene on 4H-SiC = 64
• 5.2.2 Trapped Pockets of Hydrogen Beneath SiC = 69
• 5.2.3 Triangular Indentations = 72
• 5.3 Summary = 75
• References = 76
• 6 Nanoelectromechanical Phenomena = 79
• 6.1 Imaging NEMS Like Devices with Direct Contact Electrostatic Force Microscopy = 79
• 6.1.1 Contrast Mechanism = 79
• 6.1.2 Detecting Subsurface Charge Density Beneath Graphene = 83
• 6.1.3 The Effect of Environmental Factors on the Operation of DC-EFM = 85
• 6.2 Electrostatic Heterodyne Force Microscopy (E-HFM) = 86
• 6.3 Differential Interferometry of Graphene Resonators = 91
• 6.4 Summary = 98
• References = 98
• 7 Further Work and Future Directions = 101
• 7.1 Interaction of 2D Materials with Surface Acoustic Waves = 101
• 7.1.1 Bilayer h-BN Resonators, Interaction with Surface Acoustic Waves and Flexoelectricity = 103
• 7.2 High-Frequency Electrostatic Heterodyne Force Microscopy = 105
• References = 106
• 8 Conclusion = 107
• Appendix A : Materials and Methods = 111
• Appendix B : Nanomechanical Phenomena in 2D Materials = 113
• Appendix C : Nanoelectromechanical Phenomena = 117
• Curriculum Vitae = 119