New Perspectives on Surface Passivation: Understanding the Si-Al2O3 Interface (eBook)

Parts of this thesis have been published in the following articles: 6
Journal Articles 6
Conference Proceedings 6
Supervisor’s Foreword 9
Acknowledgements 12
Contents 14
About the Author 17
Abbreviations 18
Symbols 20
1 Introduction 24
1.1 Characterisation of Surface Passivation 24
1.2 Al2O3 as a Passivating Dielectric 26
1.3 Industrial Application of Al2O3 29
1.4 Outline of This Work 30
References 31
2 Surface Recombination Theory 37
2.1 The Semiconductor Surface 37
2.2 Definition of Energies and Potentials 40
2.3 Surface Charge and Band-Bending 41
2.4 Recombination Through Defect States 43
2.5 Surface Recombination 44
2.6 Relationship to Experimental Parameters 47
References 49
3 Al2O3 Deposition and Characterisation 51
3.1 Al2O3 Deposition by APCVD 51
3.1.1 Deposition System 52
3.1.2 Process Parameters 52
3.1.3 Chemical Precursors 53
3.1.4 Temperature Profiles 57
3.2 Sample Preparation 59
3.3 Characterisation 59
References 61
4 Electrical Properties of the Si--Al2O3 Interface 63
4.1 Interface State Distribution 64
4.2 Capture Cross-Sections 67
4.2.1 The Conductance Method 67
4.2.2 Previous Work 69
4.2.3 Real and Apparent Capture Cross-Sections 70
4.2.4 Determination of ?p and ?n 73
4.2.5 Information from Temperature-Dependent Measurements 78
4.3 Comparison of Model and Experiment 81
4.4 Conclusions 84
References 85
5 Influence of Deposition Parameters 88
5.1 Substrate Temperature 88
5.1.1 H2O 89
5.1.2 O2 91
5.2 Reactant Concentration 92
5.2.1 H2O 92
5.2.2 O2 93
5.3 Chemical Precursor 94
5.4 Conclusions 97
References 98
6 Effect of Post-Deposition Thermal Processing 99
6.1 Firing 100
6.2 Rapid Thermal Annealing 109
6.3 Conclusions 115
References 115
7 Effect of Surface Dopant Concentration 117
7.1 Introduction 117
7.2 Boron-Doped Surfaces 118
7.3 Phosphorus-Doped Surfaces 129
7.3.1 Undiffused Surfaces 130
7.3.2 Diffused Surfaces 136
7.4 Consequences for Device Design 153
7.5 Conclusions 155
References 156
8 Effect of Surface Orientation and Morphology 160
8.1 Recombination at langle100 rangle, langle111 rangle, and Textured Surfaces 161
8.2 Electrical Properties of the langle100 rangle and langle111 rangle Interfaces 164
8.3 Conclusions 170
References 171
9 Relationship Between Al2O3 Bulk and Interface Properties 173
9.1 Structure and Composition 173
9.1.1 Infrared Absorption Measurements 174
9.1.2 Band Assignments 174
9.1.3 Trends and Discussion 179
9.2 Dielectric Properties 184
9.3 Optical Properties 187
9.4 Conclusions 190
References 191
10 Conclusion 195
References 197
Appendix ACapacitance–Voltage Measurements 199
Appendix BThe Conductance Method 217