In terms of the topical applications covered these include, but are not limited to, flexible displays, organic electronics, transistors, integrated circuits, semiconductors and solar cells. These offer perspectives for today?s energy and healthcare challenges, such as electrochemical energy storage and wearable devices. Finally, a section on fundamental properties and characterization approaches of flexible electronics rounds off the book.
Each contribution points out the importance of the structure-function relationship for the target-oriented fabrication of electronic devices, enabling the design of complex components.
Table of Contents
About the Series Editor xiii
Preface xv
1 Soft Composites with Tunable Optical and Electrical Properties 1
Luca Valentini and Nicola Pugno
1.1 Introduction 1
1.2 Soft Color Composites 2
1.3 Hybrid Viscoelastic Polymer Composites 2
1.4 Elastomeric Conductive Composites 7
1.5 Conclusions and Future Perspectives 9
Acknowledgments 9
References 9
2 Organic Semiconductors for Transparent Electronics 13
Hakan Usta and Antonio Facchetti
2.1 Introduction 13
2.2 Optically Transparent Semiconductor Families 16
2.2.1 Thin-film Transistors 16
2.2.2 Oligothiophenes 19
2.2.3 Fused Heteroacenes 22
2.2.4 Rylene and Fused Aromatic Dicarboximides 29
2.2.5 Other Semiconductors 39
2.3 Conclusions and Perspectives 46
References 47
3 Flexible Carbon-based Electronics: Flexible Solar Cells 51
PhilippMaisch, Luca Lucera, Christoph J. Brabec, and Hans-Joachim Egelhaaf
3.1 Introduction 51
3.2 Applications 52
3.3 Device Physics 53
3.3.1 Structure and Operating Principle 53
3.3.2 Solar Cell Characteristics 55
3.4 New Materials 57
3.5 Flexible Electrodes 59
3.6 Processing 61
3.6.1 Laboratory Scale 61
3.6.2 Industrial Scale 61
3.6.3 Solar Modules 63
3.7 Summary and Outlook 66
References 66
4 Development of Organic Field-effect Transistors for Operation at High Frequency 71
Andrea Perinot,Michele Giorgio, and Mario Caironi
4.1 Introduction 71
4.2 The Transition Frequency f t 73
4.2.1 Measurement Methods 75
4.3 High-frequency Organic Field-effect Transistors 80
4.3.1 Improvement of the Effective Charge Mobility 82
4.3.2 The Reduction of the Footprint 84
4.3.3 Achieving High-frequency Operation at a Low Bias Voltage 87
4.3.4 Integration into Upscalable Fabrication Processes 88
4.4 Conclusions and Perspectives 90
References 92
5 Graphene for Flexible Electronics 95
Bhupendra K. Sharma, Tanmoy Das, and Jong-Hyun Ahn
5.1 Introduction 95
5.2 Synthesis and Transfer Process 96
5.2.1 Chemical Vapor Deposition (CVD): Scalable Growth 97
5.2.2 Transfer Process 99
5.3 Applications 101
5.3.1 Transparent Electrodes 101
5.3.1.1 Touch Screen/Panel 102
5.3.1.2 Organic Light-Emitting Diodes 104
5.3.1.3 Photovoltaic Device 109
5.3.2 Field-Effect Transistors 113
5.3.3 Sensors 117
5.3.4 Nanogenerator for Energy Harvesting 120
5.4 Conclusions and Perspectives 123
References 123
6 Printing 2D Materials 131
Felice Torrisi and Tian Carey
6.1 Introduction 131
6.2 Printing Techniques 134
6.2.1 Spin Coating 134
6.2.2 Blade Coating 134
6.2.3 Rod Coating 135
6.2.4 Spray Coating 136
6.2.5 Screen Printing 137
6.2.6 Flexographic Printing 138
6.2.7 Gravure Printing 139
6.2.8 Inkjet Printing 141
6.3 Formulation and Characterization of Electronic Inks 142
6.3.1 Ink Rheology and Surface Chemistry 143
6.3.2 Dispersion of Functional Layered Materials 147
6.4 Exfoliation of Layered Crystals 148
6.4.1 Ultrasonication 149
6.4.2 Ball Milling 150
6.4.3 Shear Exfoliation 150
6.4.4 Microfluidization 151
6.5 Stabilization of Exfoliated Flakes 152
6.5.1 Surfactants 153
6.6 Formulation: From Dispersion to Ink 154
6.6.1 The Rheology of Inks 155
6.7 Printing and Coating of 2D-crystal-based Inks 158
6.7.1 Spin Coating 158
6.7.2 Blade and Rod Coating 158
6.7.3 Spray Coating 159
6.7.4 Screen Printing 159
6.7.5 Inkjet Printing 159
6.7.6 Characterization Techniques 163
6.8 Applications 165
6.8.1 Printed Electronics 166
6.8.2 Printed Optoelectronics 178
6.8.3 Sensors andWearable Devices 180
6.8.4 Energy Devices 180
6.8.5 Printed THz Devices 181
6.9 Outlook and Future Perspectives 182
Acknowledgments 184
References 184
7 Characterization of Graphene Flexible Materials and Displays 207
George Anagnostopoulos, John Parthenios, Konstantinos Papagelis, and Costas Galiotis
7.1 Introduction to Display Systems 207
7.2 Graphene/Flexible Polymer Electrodes 210
7.2.1 Sheet Resistance and Transmittance of Graphene/Flexible Polymer Electrodes 212
7.2.2 Mechanical Robustness of Graphene/Flexible Polymer Electrodes 216
7.3 Graphene-based Flexible Displays 219
7.4 Outlook 221
References 222
8 AMOLED Display Technology and Applications 231
Michael G. Kane
8.1 Introduction 231
8.2 Commercial Flexible AMOLED Displays 233
8.3 OLED Displays 236
8.3.1 Structure and Electro-optic Behavior 236
8.3.2 Lifetime Effects in OLEDs 239
8.4 AMOLED Display Design 239
8.4.1 TFT Technologies for Flexible AMOLED Displays 241
8.4.1.1 Polysilicon TFTs 242
8.4.1.2 Metal Oxide TFTs 244
8.4.2 AMOLED Pixel Design 245
8.4.3 Integrated Display Drivers 248
8.5 Substrates and Barrier Coatings 249
8.5.1 Substrates 249
8.5.2 Barrier Coatings 252
8.5.3 Additional Layers 255
8.5.4 Characterization of Flexibility 256
8.6 The Future of Flexible AMOLED Displays 258
References 259
9 Flexible Batteries 265
Christoph Stangl, Bernd Fuchsbichler, Martin Schmuck and Stefan Koller
9.1 Introduction 265
9.2 Electrochemical Power Sources - Theoretical Basics 265
9.2.1 Conventional (lithium-ion) battery build-up 269
9.3 Basic Material Concepts for Flexible Energy Storage Systems 270
9.3.1 Flexible Electrodes 271
9.3.2 Flexible Electrolyte 274
9.3.3 Flexible Packaging 275
9.4 Basic Design Concepts for Flexible Energy Storage Systems 276
9.4.1 Thin-film/Printed Batteries 276
9.4.2 Fiber-shaped/Cable-type Batteries 278
9.4.3 Embedded Batteries 280
9.5 Summary and Outlook 280
References 283
10 Flexible Organic Bioelectronics and Biosensors 289
Caizhi Liao and Feng Yan
10.1 Introduction 289
10.2 Organic Material 291
10.3 Flexible Organic Electronics for Biology 293
10.3.1 OTFTs 294
10.3.1.1 OFET Sensors 296
10.3.1.2 OECTs Sensors 298
10.3.2 Organic Electrodes 300
10.3.2.1 Biological Sensing 301
10.3.2.2 Neural Recording/Stimulation 301
10.3.2.3 Others 302
10.3.3 e-Textiles 303
10.4 Conclusion 305
References 306
Index 311
