Scanning Transmission Electron Microscopy: Imaging and Analysis

✍ Scribed by Stephen J. Pennycook, Peter D. Nellist

• Publisher: Springer
• Year: 2011
• Tongue: English
• Leaves: 775
• Edition: 2011
• Category: Library

✦ Synopsis

Scanning transmission electron microscopy has become a mainstream technique for imaging and analysis at atomic resolution and sensitivity, and the authors of this book are widely credited with bringing the field to its present popularity. Scanning Transmission Electron Microscopy(STEM): Imaging and Analysis will provide a comprehensive explanation of the theory and practice of STEM from introductory to advanced levels, covering the instrument, image formation and scattering theory, and definition and measurement of resolution for both imaging and analysis. The authors will present examples of the use of combined imaging and spectroscopy for solving materials problems in a variety of fields, including condensed matter physics, materials science, catalysis, biology, and nanoscience. Therefore this will be a comprehensive reference for those working in applied fields wishing to use the technique, for graduate students learning microscopy for the first time, and for specialists in other fields of microscopy.

✦ Table of Contents

Cover......Page 1
Scanning Transmission Electron Microscopy: Imaging and Analysis......Page 4
ISBN 978-1-4419-7199-9......Page 5
Preface......Page 6
Contents......Page 8
Contributors......Page 10
1.1 Baron Manfred von Ardenne......Page 14
1.2 Development of TEM......Page 16
1.3 The Crewe Innovations......Page 19
1.4 Coherent or Incoherent Imaging......Page 25
1.5 The High-Angle Annular Dark Field (HAADF) Signal......Page 33
1.6 Atomic Resolution Incoherent Imaging of Crystals......Page 36
1.7 Atomic Resolution EELS......Page 49
1.8 Atomic Resolution with TEM/STEM Instruments......Page 51
1.9 The Successful Correction of Lens Aberrations......Page 57
1.10 Next-Generation Aberration Correctors......Page 69
1.11 Outlook......Page 75
References......Page 76
2.1 Introduction......Page 104
2.2 The Principle of Reciprocity......Page 105
2.3 Interference Between Overlapping Discs......Page 106
2.4 Bright-Field Imaging......Page 110
2.5 Resolution Limits......Page 111
2.6.1 Source Spatial Coherence and Brightness......Page 112
2.7 Annular Dark-Field Imaging......Page 114
2.7.1 Incoherent Imaging with Dynamical Diffraction......Page 118
2.7.2 The Effect of Thermal Diffuse Scattering......Page 120
2.9 Optical Depth Sectioning and Confocal Microscopy......Page 122
2.10 Conclusions......Page 124
References......Page 125
3.1 Introduction......Page 130
3.2 A Brief Summary of Aberrations......Page 131
3.3 Formation of the Ronchigram......Page 133
3.4 A Geometrical Optics Approach to the Ronchigram......Page 134
3.5 Where This Description Fails......Page 136
3.6 The Nion Method for Measuring Aberrations......Page 139
3.7 Related Methods......Page 142
3.8 A Wave-Optical Approach......Page 144
3.9 Probe Formation......Page 145
3.10 An Aside on Bright-Field Imaging......Page 147
3.12 Amorphous Materials......Page 149
3.13 Coherence......Page 155
3.14 Crystalline Materials......Page 158
3.15 Comets......Page 167
3.16 Rapid Methods to Measure Defocus in the Ronchigram......Page 169
3.17 Summary......Page 170
References......Page 171
4.1 Introduction......Page 176
4.2.1.1 The Zero-Loss Peak......Page 177
4.2.1.2 The Low-Loss Region......Page 178
4.2.1.3 The Core Loss......Page 181
4.2.2 The Datacube......Page 183
4.3.1 EELS Datacube Acquisition......Page 184
4.3.2.2 Data Size and Time Issues......Page 187
4.3.2.3 Dose and Time Issues: A Comparison with EFTEM......Page 188
4.3.3.1 Chrono-SPIM......Page 190
4.3.3.2 Multiple Window SPIM......Page 192
4.3.4.2 Deconvolution......Page 193
4.3.4.4 Model Based Quantification Techniques......Page 195
4.4 Applications......Page 196
4.4.1.1 Surface and Interface Plasmons......Page 197
4.4.1.2 Gaps and Excitons......Page 200
4.4.1.3 Semi-Core Loss......Page 201
4.4.1.4 Sub-optical Wavelength Mapping......Page 202
4.4.2 Core-Loss......Page 204
4.4.2.1 Mapping and Quantifying Chemical Signals at the Nanometre Scale......Page 205
4.4.2.2 Bond Mapping......Page 207
4.4.2.3 Atomic Column Chemical and Spectroscopic Imaging......Page 209
Reference......Page 213
5.1.1 Introduction......Page 220
5.1.2 Bethe's Theory of Inelastic Scattering......Page 222
5.1.3 Probing the Local Density of States......Page 224
5.1.4 Key Approximations......Page 225
5.1.5 Anisotropy and the Experimental Conditions......Page 227
5.2.1.1 Introduction......Page 230
5.2.1.2 A Qualitative Description of the O K Edge in TiO2......Page 231
5.2.1.3 Ab Initio Calculation of the O K Edge in TiO2......Page 233
5.2.1.4 Core-Hole Effects......Page 236
5.2.2.1 Atomic Multiplet Theory......Page 238
5.2.2.2 Crystal Field Effects......Page 242
5.2.2.3 Oxidation State......Page 244
5.2.2.4 Spin State......Page 246
5.2.2.5 Charge Transfer Effects......Page 247
5.3 Applications......Page 249
References......Page 256
6.1 Introduction......Page 260
6.2.1 Calculating the Elastic Wave Function......Page 262
6.2.2 Transition Potentials......Page 268
6.2.3 Double Channelling, Single Channelling, Nonlocal Potentials and the Local Approximation......Page 269
6.2.4 Anomalous EELS Imaging and Carbon K-Shell in SiC......Page 273
6.2.5 Delocalization......Page 280
6.3 Quantitative Z-Contrast Imaging......Page 283
6.4 Chemical Mapping......Page 287
6.5 Imaging in Three Dimensions Depth Sectioning......Page 294
6.6 Summary......Page 296
References......Page 297
7.1 Introduction......Page 304
7.2 Optimum Instrument Settings for X-Ray Analysis......Page 306
7.2.1 Intensity Distribution Caused by the Finite Source Size......Page 307
7.2.2 Intensity Distribution of the GAL and CAL Probes......Page 311
7.2.3 Overall Intensity Distribution for Analysis with High Currents......Page 315
7.3.1 Spatial Resolution......Page 320
7.3.2 Analytical Sensitivity: Minimum Mass Fraction (MMF)......Page 325
7.3.3 Analytical Sensitivity: Minimum Detectable Mass (MDM)......Page 328
7.4.1 X-Ray Mapping......Page 331
7.4.2 Spectrum Imaging (SI)......Page 333
7.4.3 Multivariate Statistical Analysis (MSA)......Page 334
7.4.4 Quantitative X-Ray Analysis Procedures......Page 341
7.5.1 Comparison of Spatial Resolution of Multilayer Analysis by EELS and XEDS......Page 346
7.5.2 Determination of Local Elemental Distributions in Alloy Nanoparticles......Page 347
7.5.3 Practical Evaluation of Improved Spatial Resolution and Sensitivity of X-Ray Analysis in Aberration-Corrected STEM......Page 351
7.5.4 Towards Atomic-Column X-ray Imaging......Page 354
7.6 Concluding Remarks: Future Prospects of X-Ray Analysis......Page 357
References......Page 358
8.1 Introduction......Page 366
8.2 Tomographic Reconstruction......Page 368
8.2.1 Backprojection......Page 369
8.2.2 Resolution......Page 372
8.3.1 Acquisition......Page 374
8.3.2 Alignment......Page 376
8.3.2.2 Markerless Alignment......Page 377
8.4 Visualisation......Page 380
8.5 STEM HAADF Tomography......Page 383
8.6.1 Heterogeneous Catalysts......Page 387
8.6.2.1 Carbon Nanotubes......Page 390
8.6.2.2 Titanium Oxide Nanotubes......Page 391
8.6.4 Semiconductor Devices......Page 393
8.6.5.1 Magnetotactic Bacteria......Page 395
8.6.5.2 Ferritin......Page 396
8.6.6 Aluminium--Germanium Alloy......Page 398
8.6.7 STEM MAADF Tomography of Dislocations......Page 399
8.7 Summary......Page 401
References......Page 402
9.1 Introduction......Page 406
9.2 Electron Nanodiffraction Techniques......Page 409
9.3 Information from Diffraction Patterns......Page 415
9.3.1 Kinematical Theory of Electron Nanodiffraction......Page 416
9.3.2 Electron Probe Formation......Page 417
9.3.3 Electron Nanodiffraction from an Assembly of Atoms......Page 418
9.3.4 Convergent Beam Electron Diffraction......Page 422
9.3.5 Diffraction Pattern Symmetry and Crystal Space Group......Page 424
9.3.6 Electron Diffraction Intensity......Page 425
9.3.7 Inversion of Diffraction Patterns and Phase Retrieval......Page 429
9.4 Practice and Applications of Scanning Electron Nanodiffraction and Diffraction Imaging......Page 431
9.4.1 Electron Nanodiffraction Analysis of Nanostructures......Page 432
9.4.2 Strain Mapping of Nanodevices......Page 433
9.4.3 Imaging of Nanoscale Structural Phases......Page 436
9.5 Conclusions......Page 438
References......Page 439
10.1 Introduction: Complex Oxides......Page 442
10.2 Usefulness of High Spatial Resolution STEM-EELS Techniques to Image Light O Atoms......Page 443
10.3 Detection and Imaging of Isolated Impurities in Oxide Materials......Page 446
10.4 Measurement of Electronic Properties of Perovskites from EELS Fine Structure......Page 450
10.5.1 Atomic Resolution Measurement of Electronic Structure in High-Tc Superconductors......Page 456
10.5.2 Column-Dependent Fine Structure: Atomic Resolution Measurement of Oxidation States in Manganites......Page 459
10.5.3 Sensitivity of EELS to Spin: Spatial Mapping of a Spin-State Superlattice in Cobaltite Thin Films......Page 462
10.5.4 Interface Quantification: Structure, Roughness, Interdiffusion, and Electronic Properties......Page 464
10.5.5 Metal--Oxide Interfaces: Au--Manganite Bilayers......Page 469
10.5.6 Oxide Interfaces for Energy Applications: Colossal Ionic Conductivity in Strained YSZ--STO Superlattices......Page 471
10.6 Conclusions......Page 473
References......Page 474
11.1 Introduction......Page 480
11.2.1 Grain Boundary Character......Page 481
11.2.2 Low-Angle Grain Boundary......Page 482
11.2.3 Dislocation Core Structures of 0-Al2O3......Page 483
11.2.4 Coincidence Site Lattice (CSL) Theory and Structural Units......Page 486
11.2.5 CSL Grain Boundary in ZrO2......Page 488
11.2.6 CSL Grain Boundary in SrTiO3......Page 490
11.3.2 Grain Boundary of Y-Doped Alumina Ceramics......Page 492
11.3.3 Grain Boundaries in Pr-Doped ZnO Varistors......Page 495
11.3.4 3D Observation of Y-Doped Al2O3......Page 499
11.4.1 Equilibrium Thickness of Amorphous Layer......Page 503
11.4.2 Amorphous Films in Si3N4 Grain Boundaries......Page 505
11.5.1 Coherent and Incoherent Interfaces......Page 507
11.5.2 SiC/Ti3SiC2 Coherent Interface......Page 510
11.5.3 Interface Structure of SrTiO3/Nb0SrTiO3/SrTiO3 Superlattices (Coherent Interface)......Page 512
11.5.4 Au/TiO2 Catalyst Interface (Coherent and Incoherent Interface)......Page 515
11.6.1 Ordered Structures of Ca in Ca0.33CoO2 Thin Films......Page 518
11.6.2 Determination of Li Ion Sites in LiFePO4 Crystals......Page 522
11.6.4 Direct Visualization of Fluorine Dopants in Iron Arsenide Superconductor (STEM EELS Mapping)......Page 525
11.7 Conclusion......Page 528
References......Page 529
12.1 Introduction......Page 536
12.2 Analysis of Semiconductor Interfaces......Page 537
12.2.1 Dielectric/Semiconductor Interfaces......Page 538
12.2.2 Metal/Semiconductor Interfaces......Page 540
12.2.3 Semiconductor/Semiconductor Interfaces and Defects......Page 542
12.3.1 Embedded Nanostructures......Page 543
12.3.2 Freestanding Nanostructures......Page 544
12.5 Summary......Page 546
References......Page 547
13.1 Introduction to Heterogeneous Catalysts......Page 550
13.2.1 Z-Contrast Imaging of Supported Metal Catalysts......Page 553
13.2.2 Signal-to-Background Ratios and Single-Atom Visibility in Catalysts......Page 558
13.2.3 Probe Size Consideration for Single-Atom Visibility......Page 560
13.2.4 Bright-Field STEM Imaging......Page 563
13.3.1 Energy-Dispersive X-ray Spectroscopy in Catalysis......Page 564
13.3.2 Electron Energy Loss Spectroscopy in Catalysis......Page 567
13.4 Tomography of Catalysts......Page 570
13.5 Nanodiffraction......Page 571
13.6.1 Approaches to In Situ Electron Microscopy......Page 572
13.6.2 Environmental STEM......Page 574
13.6.3 Issues for In Situ Environmental STEM......Page 576
13.6.4 In Situ Studies on Catalyst......Page 580
13.6.5 In Situ Preparation and Evolution of Supported Bimetallic Catalysts......Page 581
13.7 Future Challenges, Developments and Opportunities......Page 585
References......Page 587
14.1 Introduction......Page 596
14.1.1 Hyperspace Crystallography......Page 598
14.1.2 Local Isomorphism......Page 600
14.2 Local Symmetry of Quasicrystals......Page 602
14.2.1 Symmetry-Breaking of Internal Clusters......Page 604
14.2.2 Cluster Symmetries and Stability......Page 607
14.3 Atomistic Fluctuations in Quasicrystals......Page 608
14.3.1 Phason----Extra Degree of Freedom......Page 609
14.3.2 Thermal Diffuse Scattering in STEM......Page 611
14.3.3 Local Debye--Waller Factor Anomaly......Page 614
14.4 Point Defects in Quasicrystals......Page 620
14.4.1 Imaging with Aberration-Corrected STEM......Page 622
14.5 Summary......Page 625
References......Page 626
15.1 Introduction......Page 628
15.2.1 Optimizing the Resolution at Low Primary Energies......Page 631
15.2.2 Cold Field Emission and Schottky Sources......Page 636
15.2.3 Practical Probe-Forming Performance......Page 640
15.2.4 HAADF and EELS Image Resolution......Page 642
15.2.5 Image Acquisition and Processing......Page 645
15.3 Graphene, Carbon Nanotubes, and Monolayer BN......Page 648
15.3.1 Graphene: Lattice Defects and Adatoms at the Graphene Edge......Page 649
15.3.2 Single-Wall Nanotubes Imaged with Atomic Resolution......Page 652
15.3.3 Monolayer BN: Distinguishing B from N and Identifying Impurities......Page 653
15.3.4 EELS of Single Heavy Atoms......Page 660
15.4.1 Present Status......Page 661
15.4.2 Future Directions......Page 664
References......Page 666
16.2 The Physics of the Low-Loss Spectrum......Page 672
16.2.1 Basic Concepts......Page 673
16.2.2 Theoretical Background......Page 675
16.3.1 Energy Resolution......Page 684
16.3.2 Monochromated Electron Probe......Page 686
16.3.3 Data Acquisition......Page 687
16.4 Interpreting Spectra......Page 688
16.4.1 Large, Strongly Peaked Dielectric Function......Page 690
16.4.2 Small, Smoothly Varying Dielectric Function......Page 692
16.4.3 Measuring the Band-Gap......Page 694
16.4.4 Surfaces......Page 695
16.4.5 Guided Light Modes......Page 697
References......Page 699
17.1 Introduction......Page 702
17.2.1 Heating Holders......Page 703
17.2.2 Cooling Holders......Page 705
17.3 Results......Page 706
17.3.1 SrTiO3 Grain Boundaries......Page 707
17.3.2 Spin State Transitions in LaCoO3......Page 712
17.3.2.1 Bulk LaCoO3......Page 713
17.3.2.2 Single-Crystal LaCoO3 Thin Film......Page 720
17.3.3 Ca3Co4O9......Page 723
17.3.3.1 High-Temperature Study of Ca3Co4O9......Page 728
17.4 Conclusions......Page 730
References......Page 731
18.1.1 Measuring Medium-Range Order......Page 738
18.2.1 Higher Order Atom Position Distribution Functions......Page 743
18.2.2 An Order/Disorder Composite......Page 747
18.2.3 Computational Models......Page 750
18.3 Fluctuation Microscopy in the TEM and STEM......Page 752
18.3.1 Data Collection and Artifacts......Page 753
18.3.2 Coherence and Chromatic Aberration......Page 756
18.3.3 Comparison to Simulation......Page 757
18.4 Probes for FEM......Page 758
18.5 STEM FEM Experiments......Page 761
18.6 Future Directions......Page 763
References......Page 765
Index......Page 770