Field Emission Scanning Electron Microscopy (eBook)

Mr. Nicolas Brodusch is the Chief Electron Microscopist in the material engineering department at McGill University, Canada since 2010. He graduated at the Université Paris-Sud, Orsay, France in Material Engineering in 1997. Involved in the field of electron microscopies since 2007, he is research interested in developing and improving new scanning electron microscopy techniques to push the limits of imaging and analysis in the field of materials science and nanomaterials. He is a world leader in diffraction and transmission techniques in the scanning electron microscope. He was awarded in 2014 for the Best Techniques and Instrumentation Development paper for year 2013 in the Microscopy and Microanalysis journal. Dr. Hendrix Demers is a Research Associate in material engineering department at McGill University, Montreal, Canada since 2012. He received his PhD in Mining and Materials Engineering at the McGill University, Montreal, Canada in 2008. He is involved in the field of microscopy and microanalysis by developing new methods for quantitative x-ray microanalysis, for materials characterization, and data and image analysis. He is also author and co-author of a world-renowned research softwares (Win X-Ray, MC X-ray, and CASINO) and aims at helping SEM users in their X-ray microanalyses, metrology applications and in more advanced applications such as electron beam lithography. He won the Castaing Award in 2008 for the best student paper and the Heinrich Award in 2010 for the Outstanding Young Scientist from the Microbeam Analysis Society of America. He is also an Academic Editor of the Scanning journal.Prof. Raynald Gauvin is full Professor at McGill University, Montréal, Canada. His research interest are related in developing new methods to characterize the microstructure of materials using high resolution scanning electron microscopy with x-ray microanalysis and Monte Carlo simulations. He is the creator of the CASINO program that is used by more than 10 000 users in the world. He has more than 300 papers in scientific journals and conference proceedings. He was Invited Speaker in more than 100 international scientific conferences. He won several scientific prices, most notably the 31st Canadian Materials Physics Medal in 2007 by the Metallurgical Society of the Canadian Institute of Mining, the Heinrich Award in 1997 from the Microbeam Analysis Society of America and the Prix d'excellence du Président de l’École for the best Doctorate Thesis defended in 1990 at l’École Polytechnique de Montréal. Pr. Gauvin was the President of the Inter American Societies of Electron Microscopy (CIASEM) from 2009 to 2011, the President of the Microbeam Analysis Society of America (MAS) from 2005 to 2006, the President of the Microscopical Society of Canada (SMC) from 2001 to 2003 and the President of the International Union of the Microbeam Analysis Societies (IUMAS) from 2000 to 2005. He is currently the holder of the Birks Chair in Metallurgy.

Contents 6
Acronyms 9
Symbols 11
1 Introduction 13
References 15
2 Developments in Field Emission Gun Technologies and Advanced Detection Systems 17
2.1 Cold-Field Emission Technology 17
2.2 CFE-SEM for Low Voltage Microscopy 20
2.3 Scanning Transmission Microscopy in the SEM 23
References 23
3 Electron Detection Strategies for High Resolution Imaging: Deceleration and Energy Filtration 25
3.1 Principles 25
3.2 Application of Dual In-Lens Electron Detection 34
3.3 Energy filtration 38
References 46
4 Low Voltage SEM 48
4.1 Strategy of Characterization: Deceleration and Energy Filtration 49
4.2 High Resolution Imaging 50
4.3 Low Voltage, Specimen Charging, and Material Contrast 52
4.4 Ultra-Low Voltage SEM: Uses and Limitations 54
References 56
5 Low Voltage STEM in the SEM 58
References 63
6 The f-Ratio Method for X-Ray Microanalysis in the SEM 65
6.1 The Limits of X-Ray Microanalysis Models 65
6.2 Description of the f-Ratio Method 65
6.2.1 f-Ratio Method for Binary System 67
6.2.2 Generalization of the f-Ratio Method for Multi-elements 69
6.3 Examples of Quantitative X-Ray Analysis Using the f-Ratio Method 69
6.3.1 Binary Examples 69
6.3.1.1 Quantification of Au–Cu Binary Alloy with a CFE-SEM 69
6.3.1.2 Quantification of Al–Mg Diffusion Couple 71
6.3.2 Multi-elements Example 71
6.3.2.1 Quantification of Al–Mg–Zn Ternary Alloy with a CFE-SEM 71
6.4 Summary 73
References 73
7 X-Ray Imaging with a Silicon Drift Detector Energy Dispersive Spectrometer 76
7.1 X-Ray Emission Rate with Low Accelerating Voltage and Thin Film 77
7.2 Comparison of Silicon Drift Detector Geometry 79
7.2.1 Solid Angle 80
7.2.2 Takeoff Angle 81
7.3 X-Ray Map Acquisition at High Spatial Resolution and High Signal-to-Noise Ratio 83
7.3.1 Low Accelerating Voltage 84
7.3.2 Low Voltage STEM 86
7.3.3 Phase Map Analysis 88
7.3.4 Removal of the Effect of Electron Channeling on X-Ray Emission in Thin Specimens 90
7.4 Summary 91
References 91
8 Electron Diffraction Techniques in the SEM 94
8.1 Electron Channeling Contrast Imaging 95
8.2 Low Voltage STEM Defects Imaging 98
8.3 Electron Backscatter Diffraction 100
8.4 Dark-Field Electron Backscatter Diffraction 102
8.5 Transmission Forward Electron Backscatter Diffraction 105
8.6 Dark-Field Imaging with a Forecaster Detector in Transmission Mode 109
References 110
9 Magnetic Domain Imaging 115
9.1 Type-I Contrast 115
9.2 Type-II Contrast 116
9.3 Type-III Contrast 119
References 120
10 Advanced Specimen Preparation 122
10.1 Surface Preparation 122
10.2 Surface Cleaning 126
10.3 Charging Compensation with Ionic Liquid Treatment 129
References 133
11 Conclusion and Perspectives 136
Index 139