Materials Challenges : Inorganic Photovoltaic Solar Energy

[BOOK DESCRIPTION]
This authoritative reference covers the various aspects of materials science that will impact on the next generation of photovoltaic (PV) module technology. The emphasis on materials brings a fresh perspective to the literature and highlights crucial issues. Special attention is given to thin film PV materials, an area that is growing more rapidly than crystalline silicon and could dominate in the long term. The book addresses the fundamental aspects of PV solar cell materials and gives a comprehensive description of each major thin film material, either in research or production. Particular weight is given to the key materials drivers of solar conversion efficiency, long term stability, materials costs, and materials sustainability.

[TABLE OF CONTENTS]

Chapter 1 Introduction and Techno-economic         1  (26)
Background
          Stuart J.C. Irvine
          Chiara Candelise
    1.1 Potential for PV Energy Generation as      1  (2)
    Part of a Renewable Energy Mix
    1.2 Historical Development of Thin Film PV     3  (3)
    1.3 The Role of Inorganic Thin Film PV in      6  (2)
    the Mix of PV Technologies
    1.4 Costs of Photovoltaics and Recent PV       8  (5)
    Industry Developments
    1.5 Role of Materials Cost and Efficiency      13 (6)
    in Cost of Thin Film PV
    1.6 Future Prospects for Cost Reduction and    19 (1)
    Thin Film PV
    1.7 Outline of Book and Context of Topics      20 (2)
    in Terms of Techno-economic Background
    References                                     22 (5)
Chapter 2 Fundamentals of Thin Film PV Cells       27 (26)
          Stuart J.C. Irvine
          Vincent Barrioz
    2.1 Introduction                               27 (3)
      2.1.1 The Sun and Solar Energy               28 (1)
      2.1.2 History of Exploiting Solar            29 (1)
      Electricity
    2.2 Fundamentals of PV Materials               30 (7)
      2.2.1 Electrical Properties of Inorganic     30 (1)
      Materials
      2.2.2 Doping of Semiconductors               31 (1)
      2.2.3 Band Structure of Solar Absorbers      32 (5)
    2.3 The pn Junction                            37 (9)
      2.3.1 Fundamentals of Absorption of Solar    39 (1)
      Radiation in a pn Device
      2.3.2 Electrical Behaviour of a PV Solar     40 (2)
      Cell
      2.3.3 Shockley-Queisser Limit                42 (2)
      2.3.4 3-G Solar Cells to Beat the Single     44 (2)
      Junction Limit
    2.4 Defects in Thin Film PV Materials          46 (4)
      2.4.1 Staebler-Wronski Effect                47 (1)
      2.4.2 Minority Carrier Lifetime and          47 (3)
      Junction Defects
      2.4.3 Lateral Non-uniformity of Thin Film    50 (1)
      PV Devices
    2.5 Conclusions                                50 (1)
    Acknowledgements                               51 (1)
    References                                     51 (2)
Chapter 3 Crystalline Silicon Thin Film and        53 (36)
Nanowire Solar Cells
          Hari S. Reehal
          Jeremy Ball
    3.1 Introduction                               53 (1)
    3.2 Planar Thin Film Crystalline Silicon       54 (15)
    Technology
      3.2.1 Crystallisation of Amorphous Silicon   54 (3)
      3.2.2 Seed Layer Approaches                  57 (7)
      3.2.3 Lift-Off and Epitaxy Approaches        64 (2)
      3.2.4 Plasmonic Enhancement in Thin          66 (3)
      Crystalline Silicon Cells
    3.3 Silicon Nanowire Solar Cells               69 (12)
      3.3.1 SiNW Growth using the                  70 (6)
      Vapour-Liquid-Solid Method
      3.3.2 Etched SiNWs and Solar Cells           76 (5)
    3.4 Conclusions                                81 (1)
    References                                     82 (7)
Chapter 4 A Review of NREL Research into           89 (46)
Transparent Conducting Oxides
          Timothy J. Coutts
          James M. Burst
          Joel N. Duenow
          Xiaonan Li
          Timothy A. Gessert
    4.1 Introduction                               89 (2)
    4.2 Practical Challenges Facing TCOs           91 (2)
      4.2.1 Elemental Abundance and Cost           91 (1)
      4.2.2 Toxicity                               91 (1)
      4.2.3 Ease of Deposition                     92 (1)
      4.2.4 Stability                              92 (1)
      4.2.5 Contacting                             92 (1)
    4.3 Background Science                         93 (2)
      4.3.1 The Transmission Window                93 (2)
    4.4 Binary Compounds                           95 (20)
      4.4.1 ZnO                                    95 (6)
      4.4.2 In2O3-Based TCOs                       101(5)
      4.4.3 SnO2                                   106(7)
      4.4.4 CdO                                    113(2)
    4.5 Ternary Compounds and Alloys               115(12)
      4.5.1 Cadmium Stannate                       115(7)
      4.5.2 Zinc Stannate                          122(2)
      4.5.3 ZnxMg1-xO                              124(3)
    4.6 Summary                                    127(1)
    Acknowledgements                               128(1)
    References                                     129(6)
Chapter 5 Thin Film Cadmium Telluride Solar        135(25)
Cells
          Andrew J. Clayton
          Vincent Barrioz
    5.1 Introduction                               135(2)
    5.2 CdS n-type Window Layer                    137(2)
      5.2.1 Doped CdS                              138(1)
      5.2.2 High Resistive Transparent Layer       138(1)
      5.2.3 Wide Bandgap Cdi1-xZnxS Alloy          138(1)
      Window Layer
    5.3 CdTe p-type Absorber Layer                 139(2)
      5.3.1 Doping CdTe                            140(1)
    5.4 CdCl2 Activation Treatment                 141(3)
      5.4.1 Recrystallisation of CdTe Grains       142(1)
      5.4.2 Inter-diffusion at the CdS-CdTe        142(1)
      Interface
      5.4.3 Passivation of Grain Boundary          143(1)
      Defects within CdTe
    5.5 Back Contact Formation                     144(3)
      5.5.1 CuxTe                                  145(1)
      5.5.2 ZnTe:Cu                                145(1)
      5.5.3 Ni-P                                   146(1)
      5.5.4 Sb2Te3                                 146(1)
      5.5.5 CdTe:As+                               146(1)
    5.6 MOCVD CdTe Cells                           147(5)
      5.6.1 MOCVD Cd1-xZnxS vs. CdS Window Layer   147(2)
      5.6.2 MOCVD CdTe:As Absorber and Contact     149(3)
      Layer
    5.7 Prospects for Large-scale Manufacture      152(2)
    using MOCVD
    5.8 Conclusions                                154(1)
    References                                     155(5)
Chapter 6 New Chalcogenide Materials for Thin      160(49)
Film Solar Cells
          David W. Lane
          Kyle J. Hutchings
          Robert McCracken
          Ian Forbes
    6.1 Introduction and Background                160(8)
    6.2 Investigating New Materials                168(15)
      6.2.1 Conventional versus High Throughput    168(1)
      Techniques
      6.2.2 One- and Two-dimensional Libraries     169(4)
      6.2.3 Mapping Libraries                      173(8)
      6.2.4 Device Libraries                       181(2)
    6.3 CZTS and Cu2ZnSnS4                         183(7)
      6.3.1 Growth of CZTS                         184(1)
      6.3.2 CZTS Device Structures and             185(2)
      Efficiencies
      6.3.3 Composition and Formation of CZTS      187(3)
    6.4 Sulfosalts                                 190(12)
      6.4.1 Cu-Sb-(S,Se)                           193(3)
      6.4.2 Cu-Bi-S                                196(2)
      6.4.3 Sn-Sb-S                                198(4)
    6.5 Conclusions                                202(1)
    References                                     203(6)
Chapter 7 III-V Solar Cells                        209(38)
          James P. Connolly
          Denis Mencaraglia
    7.1 Introduction                               209(1)
    7.2 Materials and Growth                       210(5)
      7.2.1 The III-V Semiconductors               210(3)
      7.2.2 Growth Methods                         213(1)
      7.2.3 Heterogeneous Growth                   214(1)
    7.3 Design Concepts                            215(12)
      7.3.1 Light and Heat                         216(1)
      7.3.2 Charge Neutral Layers                  217(2)
      7.3.3 Space Charge Region                    219(1)
      7.3.4 Radiative Losses                       219(2)
      7.3.5 Resulting Analytical Model             221(2)
      7.3.6 Single Junction Analyses               223(4)
      7.3.7 Conclusions                            227(1)
    7.4 Multi-junction Solutions                   227(13)
      7.4.1 Theoretical Limits                     227(2)
      7.4.2 Material Limitations                   229(3)
      7.4.3 A Tandem Junction Example              232(3)
      7.4.4 Record Efficiency Triple Junction      235(4)
      7.4.5 Conclusions                            239(1)
    7.5 Remarks on Nanostructures                  240(2)
    7.6 Conclusions                                242(1)
    References                                     243(4)
Chapter 8 Light Capture                            247(50)
          Stuart A. Boden
          Tristan L. Temple
    8.1 Introduction                               247(1)
    8.2 The Need for Antireflection                248(1)
    8.3 The Need for Light Trapping                249(1)
    8.4 Mechanisms                                 250(3)
      8.4.1 Antireflection                         250(1)
      8.4.2 Light Trapping                         251(2)
    8.5 Thin Film Antireflection Coatings          253(5)
      8.5.1 Optical Considerations                 253(4)
      8.5.2 Surface Passivation                    257(1)
      8.5.3 Other Thin Film Considerations         257(1)
    8.6 Micron-scale Texturing                     258(6)
      8.6.1 Alkali Etching: Pyramids and Grooves   258(2)
      8.6.2 Acid Etching                           260(2)
      8.6.3 Dry Etching                            262(1)
      8.6.4 Ablation Techniques                    263(1)
    8.7 Submicron Texturing                        264(9)
      8.7.1 Subwavelength Array Theory             265(2)
      8.7.2 Subwavelength Texturing Practical      267(6)
      Realization
    8.8 Metal Nanoparticle Techniques              273(11)
      8.8.1 Optical Properties of Metal            273(7)
      Nanoparticles
      8.8.2 Fabrication of Metal Nanoparticles     280(3)
      8.8.3 Integration of Metal Nanoparticles     283(1)
      into Silicon Solar Cells
    8.9 Summary                                    284(1)
    References                                     285(12)
Chapter 9 Photon Frequency Management Materials    297(35)
for Efficient Solar Energy Collection
          Lefteris Danos
          Thomas J.J. Meyer
          Pattareeya Kittidachachan
          Liping Fang
          Thomas S. Parel
          Nazila Soleimani
          Tomas Markvart
    9.1 Introduction                               297(2)
    9.2 Fundamentals                               299(4)
      9.2.1 Introduction                           299(1)
      9.2.2 Re-absorption                          299(3)
      9.2.3 Photon Balance in the Collector        302(1)
    9.3 Forster Resonance Energy Transfer          303(8)
      9.3.1 Introduction                           303(1)
      9.3.2 Basic Theory                           304(2)
      9.3.3 Materials for Improved Photon          306(1)
      Energy Collection
      9.3.4 Estimation of Quantum Yield            306(2)
      9.3.5 Examples of Energy Transfer for        308(3)
      Efficient Photon Management
    9.4 Luminescent Solar Collectors               311(8)
      9.4.1 Introduction                           311(3)
      9.4.2 Spectroscopic Characterisation of      314(2)
      LSCs
      9.4.3 LSC Examples                           316(3)
    9.5 Luminescence Down-Shifting (LDS)           319(4)
      9.5.1 Introduction                           319(2)
      9.5.2 LDS Examples                           321(2)
    9.6 Advanced Photonic Concepts                 323(4)
    9.7 Conclusions                                327(1)
    Acknowledgements                               327(1)
    References                                     328(4)
Subject Index                                      332