ISBN: 3-540-65199-3
TITLE: Applied RHEED
AUTHOR: Braun, Wolfgang
TOC:

1. MBE-Grown Semiconductor Interfaces 1
1.1 Molecular-Beam Epitaxy 1
1.2 Interface Formation 3
1.3 GaAs/AlAs Surfaces 7
2. Reflection High-Energy Electron Diffraction (RHEED) 13
2.1 Geometry and Experimental Conditions 13
2.2 Instrumentation and Miscellaneous RHEED Techniques 17
2.3 Theoretical Models 19
2.3.1 Kinematical Scattering 20
2.3.2 Dynamical Scattering 25
3. RHEED Oscillations 27
3.1 Current Experimental Status 27
3.2 Theoretical Models 35
3.2.1 BirthDeath Models 35
3.2.2 Kinematical Model 38
3.2.3 Edge-Scattering Model 38
3.2.4 Dynamical Approaches 39
3.2.5 Top-Layer Interference Model 39
4. Semikinematical Simulations of RHEED Patterns 43
4.1 Different Models for the Surface Reconstruction of GaAs (113)A 44
4.2 Misoriented GaAs (113)A51
4.3 (001) GaAs (24)/c(28) 54
4.3.1 Depth Modulation 56
4.3.2 Shadowing and Average Layer Potential 58
4.3.3 Relaxation, DoyleTurner and DebyeWaller Corrections 61
4.3.4 The [110] Azimuth 63
4.4 Domains 64
5. Kikuchi Lines 75
5.1 A Simple Scheme for the Geometrical Construction of Kikuchi Patterns 75
5.1.1 Three-Dimensional Lines 75
5.1.2 Extension to Fewer Than Three Dimensions 79
5.2 Determination of Average Crystal Potential and Misorientation 82
5.3 Where do Kikuchi Lines Originate? 87
6. RHEED with Rotating Substrates 91
6.1 Gated Detection 92
6.2 Azimuthal Scans 93
6.3 RHEED Oscillations 99
7. Reconstruction-Induced Phase Shifts of RHEED Oscillations 109
7.1 Phase Shifts at GaAs/AlAs Heterointerfaces 110
7.1.1 Variation of As_4 Pressure 111
7.1.2 Variation of Substrate Temperature 112
7.1.3 Variation of the Growth Rate 117
7.1.4 Variation of Diffraction Conditions 118
7.2 Experimental Results 118
7.2.1 Sampling Depth of RHEED 119
7.2.2 Phase Shifts and Surface Reconstructions 121
7.2.3 Phase Shift Variation Along a Streak 127
7.2.4 Decoupling of Phase on Different Streaks 129
8. Energy Loss Spectroscopy During Growth 133
8.1 Electron Loss Spectroscopy on Static Surfaces 136
8.2 ELS-RHEED Intensity Oscillations 142
9. Phase Shifts: Models 145
9.1 Growth-Induced Phase Shifts 145
9.2 Diffraction-Induced Phase Shifts: The Top-Layer Interference Model 148
9.2.1 A Basic Model 148
9.2.2 Comparison With Experiments 154
9.2.3 Phase Shifts at Interfaces 161
10. Applications of Reconstruction-Induced Phase Shifts 165
10.1 Ga Segregation at AlAs/GaAs Interfaces 165
10.1.1 (001) Interfaces 165
10.1.2 (113)A Interfaces 174
10.2 Modifying the Surface Reconstruction: Tin Doping 179
10.3 Modifying the Surface Morphology: Carbon Doping 182
10.4 Silicon Doping 185
10.4.1 Dependence of the Phase Shift on Si Concentration 185
10.4.2 Si-Induced Kinks 188
10.4.3 Si Segregation 189
10.4.4 GaAs/AlAs (001) Revisited 194
11. Closing Remarks 197
References 201
Index 211
Color Plates 217
END
