Surface analysis with STM and AFM: experimental and theoretical aspects of image analysis

Sergei N. Magonov, Myung-Hwan Whangbo3527293132, 9783527293131

Scanning tunneling microscopy (STM) and atomic force microscopy (AFM) are powerful tools for surface examination. In the past, many STM and AFM studies led to erroneous conclusions due to lack of proper theoretical considerations and of an understanding of how image patterns are affected by measurement conditions. For this book, two world experts, one on theoretical analysis and the other on experimental characterization, have joined forces to bring together essential components of STM and AFM studies: The practical aspects of STM, the image simulation by surface electron density plot calculations, and the qualitative evaluation of tip-force induced surface corrugations. Practical examples are taken from: * inorganic layered materials * organic conductors * organic adsorbates at liquid-solid interfaces * self-assembled amphiphiles * polymers This book will be an invaluable reference work for researchers active in STM and AMF as well as for newcomers to the field.

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Table of contents :
Surface Analysis with STM and AFM……Page 2
Contents……Page 10
Preface……Page 8
1.1 Development of Scanning Probe Microscopy……Page 16
1.2.1 Image Interpretation……Page 17
1.2.2 Tip-Sample Interactions……Page 19
1.2.3 Surface Relaxation and Local Hardness……Page 20
1.2.4 Surface Forces and AFM……Page 21
References……Page 22
2.1 Electron Transport Processes……Page 24
2.1.2 Electronic and Mechanical Contact Regimes……Page 25
2.2 Survey of Force Interactions……Page 26
2.2.1 Force-vs.-Distance Curves……Page 27
2.2.2 Short-Range Forces and Sample Deformation……Page 28
2.2.3.1 Long-Range Forces……Page 31
References……Page 33
3 Scanning Probe Microscopes……Page 36
3.1 Operating Principles and Main Components……Page 37
3.1.2 Tip-Sample Approach and Electronic Feedback……Page 38
3.1.3 Scanning Modes and Parameters……Page 39
3.1.4 Images and Filtering……Page 40
3.2.1 STM Tips and Current Detection……Page 42
3.2.2 Bias Voltage……Page 43
3.2.3 Scanning Tunneling Spectroscopy……Page 45
3.3 Atomic Force Microscope……Page 46
3.3.1 Contact Mode and Force Detection……Page 48
3.3.2 AFM Probes……Page 50
3.3.3 Dynamic AFM Measurements……Page 52
3.3.3.1 AFM Operation in the Attractive Force Regime……Page 53
3.3.3.4 Magnetic Force Microscopy……Page 54
3.4.1 Resolution in STM and AFM……Page 55
3.4.2 Metrological Applications……Page 58
References……Page 59
4.1 Samples……Page 62
4.2.1 Optimization of STM Experiments……Page 63
4.2.2 Optimization of Contact-Mode AFM Experiments……Page 65
4.2.3 Optimization of Tapping-Mode AFM Experiments……Page 68
4.3.1 Large-Scale Imaging……Page 70
4.3.2 Atomic-Scale Imaging……Page 72
4.3.3 Image Artifacts……Page 73
References……Page 77
5.1 Electronic Structures of Solids……Page 80
5.2.1 Tunneling Between Metals……Page 83
5.2.2 Tunneling Between Metal and Semiconductor……Page 84
5.2.3 Tersoff-Hamman Theory and its Extension……Page 87
5.2.4 Other Theories……Page 88
5.4.1 STM Image Simulation……Page 89
5.4.2 AFM Image Simulation……Page 91
5.4.3 STM and AFM Images of Graphite……Page 92
References……Page 95
6.1 Layers from MX6 Trigonal Prisms and Octahedra……Page 98
6.2.1 2H­MoS2……Page 101
6.2.2 MoOCl2……Page 103
6.2.3 WTe2……Page 104
6.2.4 NbTe2……Page 107
6.2.5 β-Nb3I8……Page 109
6.2.6 IT­TaSe2……Page 113
6.3.1 Observations……Page 120
6.3.2 Origin of Nonuniform Charge Distribution……Page 122
6.4 Concluding Remarks……Page 124
References……Page 125
7.1 Imperfections in Compounds with Metal Clusters……Page 128
7.2 Point Defects in Semiconductor 2H-MoS2……Page 131
7.3 Cases Tractable by Electronic Band Structure Calculations……Page 133
7.3.1 Ligand-Atom Vacancy……Page 134
7.3.3 Donor Substitution at the Metal Site……Page 135
7.4.1 Donor Substitution at the Ligand Site……Page 138
7.4.1.1 The Case of Negative Bias……Page 139
7.4.2 Acceptor Substitution at the Ligand Site……Page 140
7.4.2.1 The Case of Positive Bias……Page 141
7.4.3 Acceptor Substitution at the Metal Site……Page 142
7.5 Survey of Image Imperfections Observed for d2 2H-MX2 Systems……Page 143
7.5.1 Atomic-Scale Images……Page 144
7.5.2 Nanometer-Scale Images……Page 146
7.6 Concluding Remarks……Page 148
References……Page 149
8.1.1 Tip Electronic States……Page 150
8.1.2 Tip-Induced Local States……Page 151
8.2 Force Interactions in STM……Page 152
8.2.1 Force Interactions in Ambient Conditions……Page 153
8.2.2 Force Interactions in Ultra High Vacuum (UHV)……Page 155
8.3.1 Force Interactions on the Atomic Scale……Page 160
8.3.2 Surface Deformation……Page 161
References……Page 163
9.1.1 Three-for-Hexagon Pattern of HOPG……Page 166
9.1.2 Hexagonal Moiré Patterns in STM Images……Page 169
9.2 Wagon-Wheel Patterns of MoSe2 Epilayers on MoS2……Page 172
9.3 STM and AFM Images of a­RuC1, and a­MoCI3……Page 174
9.3.1 Images of a­RuCI3 at Low Applied Force……Page 175
9.3.3 Tip Force Induced Surface Deformation in a­RuCI3……Page 178
9.3.4 AFM Images of a­MoCI3……Page 182
9.4.1 Atomic-Scale Deformation in the Commensurate Tellurides……Page 184
9.4.2 Structure of Incommensurate Telluride TaGe 0.355Te2……Page 191
9.5 Tip Force Induced Changes in AFM Images of NbTe2……Page 192
9.6 Nanoscale Ring Structure of MoS2 and WSe2……Page 195
9.7 Concluding Remarks……Page 199
References……Page 200
10.1 Crystal and Electronic Structure……Page 204
10.2 Early STM Studies of Organic Conductor……Page 208
10.3.1 Surface Processes During Imaging……Page 209
10.3.2 Molecular-Scale Images……Page 211
10.4.1 TTF-TCNQ……Page 214
10.4.2 Qn(TCNQ)2……Page 216
10.4.3 4EP(TCNQ)2……Page 217
10.4.4 TEA(TCNQ)2……Page 219
10.4.5 TCNQ Salts with Substituted Phenylpyridines……Page 220
10.5.1 Cation-Layer Images of a-Phases……Page 221
10.5.2 HOMO Density of β-(BEDT-TTF)2I3……Page 224
10.5.4 Anion-Layer Images of k-Phases……Page 227
10.6 Concluding Remarks……Page 231
References……Page 232
11.1.1 Organic Compounds and Substrates……Page 234
11.1.2 STM Imaging at Liquid/Solid Interfaces……Page 236
11.2.1 Images of Normal Alkanes on HOPG……Page 238
1 1.2.2 Molecular Order of Cycloalkane Adsorbates on HOPG……Page 243
11.3.1 Molecular-Scale Images of Normal Alkanes on β-­Nb3I8……Page 248
11.3.2 4-Alkyl-4′-cyanobiphenyls on HOPG……Page 250
11.3.3 4-Alkyl-4′-cyanobiphenyls on β-Nb3I8……Page 252
References……Page 256
12.1.1 Morphology and Molecular Order……Page 258
12.1.2 Nanomechanical Properties……Page 259
12.2.1 Basic Principles……Page 260
12.2.2 Sample Preparation and AFM Imaging……Page 261
12.3.1 Crystal Structures……Page 265
12.3.2.1 Thin Overlayers……Page 268
12.3.2.2 Double Layers……Page 270
12.3.3.1 Micellar Structures……Page 272
12.3.3.2 Fiber-Like Assemblies……Page 274
12.3.3.3 Rod-Like Assemblies……Page 276
12.3.4 Structural Models……Page 279
12.4.1 Self-Assembled Structures of 10MS……Page 281
12.4.2 Self-Assembled Structures of 16MS……Page 284
12.4.3 Structural Models……Page 288
12.5 Concluding Remarks……Page 289
References……Page 290
13.1.1 Polymer Structure……Page 292
13.1.3 Applying STM and AFM……Page 294
13.2.1 Conducting Polymers……Page 296
13.2.2 Metal-Coated Polymer Surfaces……Page 297
13.2.3 Polymer Layers on Conducting Substrates……Page 298
13.3.1 Polydiacetylene Single Crystal……Page 299
13.3.2 Polyethylene Single Crystal……Page 301
13.3.3 Polymer Spherulites……Page 306
13.4.1 Imaging of Molecular Chain Order……Page 309
13.4.2 Nanostructure of Polyethylene Tapes and Fibers……Page 311
13.5 AFM of Di-Block Copolymers……Page 318
13.5.1 Poly(styrene-b-isoprene) Films……Page 320
13.5.2 Poly(styrene-b-methyl methacrylate) and Poly(styrene-b-2-vinyl-pyridine) Films……Page 321
13.6 Concluding Remarks……Page 323
References……Page 325
14 Future Outlook……Page 328
Acknowledgements……Page 332
Index……Page 334