Wide-Gap Chalcopyrites

Contents......Page 8
1 Cu-Chalcopyrites–Unique Materials for Thin-Film Solar Cells......Page 15
References......Page 20
2.1 Introduction......Page 23
2.2.1 Barrier Heights of I–III–VI[sub(2)] Schottky Contacts......Page 25
2.2.2 Valence-Band Offsets of I–III–VI[sub(2)] Heterostructures......Page 32
2.3 IFIGS-and-Electronegativity Theory......Page 34
2.4.1 IFIGS-and-Electronegativity Theory......Page 37
2.5 Conclusions......Page 43
References......Page 44
3.1 Introduction......Page 49
3.2 Fermi-Level Stabilization Energy......Page 51
3.3 Amphoteric Native Defects......Page 52
3.4 Maximum Doping Limits in GaAs......Page 54
3.6 Group III–N–V Alloys......Page 57
3.7 Group II–VI Semiconductors......Page 60
3.8 Group I–III–VI[sub(2)] Chalcopyrites......Page 62
3.9 Conclusions......Page 63
References......Page 64
4.1 Introduction......Page 69
4.2 Why a Cu Leak Causes Anion Vacancies and Cu Antisite Defects......Page 72
4.3 Is [equation omitted]......Page 75
4.4 Is the High-Voltage Cu-Chalcopyrite Case Hopeless?......Page 76
4.5 How to Confine Copper......Page 77
References......Page 80
5.1 Introduction......Page 83
5.2 The Photocapacitance Method......Page 85
5.3 Photocapacitance Spectra for the Cu(InGa)Se[sub(2)] Alloys......Page 88
5.4 Determination of Minority Carrier Collection......Page 92
5.5 Photocapacitance Spectra in the Cu(InAl)Se[sub(2)] Alloys......Page 97
5.6 Conclusions......Page 100
References......Page 101
6.1 Introduction......Page 105
6.2.1 CuInSe[sub(2)] Cells......Page 106
6.2.2 Wide-Gap Chalcopyrite Cells......Page 108
6.3 Role of Surface Band Gap Widening......Page 110
6.4 Analytical Model for the Heterointerface......Page 111
6.5.1 Numerical Modeling......Page 116
6.5.2 Influence of Surface Bandgap Widening......Page 118
6.5.3 Influence of Excess Defects......Page 119
6.5.4 Wide-Gap Chalcopyrite Absorbers......Page 121
6.6 Conclusion......Page 122
References......Page 123
7.1 Introduction: Native Defects and Doping in CuGaSe[sub(2)]......Page 126
7.2.1 Defect Spectroscopy by Photoluminescence......Page 127
7.2.2 Electrical Transport Measurements by Hall Effect......Page 133
7.3.1 Defects in CuInSe[sub(2)]......Page 137
7.3.2 Defects in CuGaSe[sub(2)]......Page 139
7.4.1 Sample Preparation......Page 141
7.4.2 Photoluminescence Spectra of CuGaSe[sub(2)]......Page 143
7.4.3 Comparison with CuInSe[sub(2)]......Page 151
7.4.4 Defect Spectroscopy of CuGaSe[sub(2)] by Hall Measurements......Page 156
7.5.1 Comparison between PL and Hall Measurements......Page 159
7.5.2 Defects in CuGaSe[sub(2)] and CuInSe[sub(2)]......Page 160
7.6 Appendix: Effective Masses and Dielectric Constants......Page 161
References......Page 162
8.1 Introduction......Page 170
8.3 Samples......Page 171
8.4 Analyses......Page 172
8.5 Experimental Results with Lateral Sub-Micro Resolution......Page 175
8.6 Analysis of Spatial Inhomogenities by Erosion–Dilatation Operations......Page 182
8.7 Novel Method for Depth Resolution of the Quality of the Photo Excited State......Page 183
8.8 Conclusions......Page 188
References......Page 189
9.1 Introduction......Page 191
9.2.2 The Transmission Electron Microscope......Page 192
9.2.3 Cathodoluminescence Analysis in the Transmission Electron Microscope......Page 194
9.3 Results......Page 195
9.3.1 Role of Texture and Na Content......Page 196
9.3.2 Electron Irradiation Damage......Page 199
9.4 Summary and Outlook......Page 201
References......Page 202
10.1 Introduction......Page 204
10.2 Experimental Method......Page 206
10.3.1 Surface Condition and Cleanness......Page 207
10.3.3 Surface Inhomogeneities......Page 211
10.3.4 Cross-Sectional Studies on Complete Devices......Page 215
10.4 Conclusion and Outlook......Page 221
References......Page 222
11.1 Introduction......Page 224
11.2 Experimental Details......Page 225
11.3.1 Single Crystal Cu(In,Ga)(S,Se)[sub(2)]......Page 227
11.3.2 Thin Film Cu(In,Ga)Se[sub(2)]......Page 229
11.3.3 Discussion......Page 231
11.4 Fermi-Level-Dependent Defect Formation......Page 235
11.5 Importance of Interfaces for V[sub(oc)] Saturation......Page 239
References......Page 242
12.1 Introduction......Page 245
12.2 Device Preparation and Characterization......Page 246
12.3.1 Solar Cell Efficiency from the One-Diode Model......Page 248
12.3.2 Temperature Dependence of Module Performance......Page 251
12.3.3 Module Simulation......Page 253
12.4.1 Introduction......Page 256
12.4.2 Deposition of Graded Absorbers......Page 257
12.4.3 Analysis of Solar Cells with Graded Absorbers......Page 258
12.5 Summary......Page 261
References......Page 262
F......Page 265
T......Page 266
X......Page 267