Following an introduction to the topic, the book discusses the materials and processes required for printed electronics, covering conducting, semiconducting and insulating materials, as well as various substrates, such as paper and plastics. Subsequent chapters describe the various building blocks for printed electronics, while the final part describes the resulting novel applications and technologies, including wearable electronics, RFID tags and flexible circuit boards.
Suitable for a broad target group, both industrial and academic, ranging from mechanical engineers to ink developers, and from chemists to engineers.
Table of Contents
Preface xi
Acknowledgment xiii
Part I Materials and Processes for Printed Electronics 1
1 Introduction 3
1.1 Connected SmartWorld 3
1.2 Smart Electronic Systems 4
1.3 Overview of the Book 6
References 8
2 Functional Electronic Inks 11
2.1 Introduction 11
2.1.1 Printing Technologies 11
2.1.1.1 Screen Printing 11
2.1.1.2 Gravure Printing 12
2.1.1.3 Flexographic Printing 12
2.1.1.4 Offset Printing 13
2.1.1.5 Inkjet Printing 13
2.1.1.6 Aerosol Printing 15
2.1.2 Fluid Requirements for Inkjet Inks 15
2.1.2.1 Boiling Point 16
2.1.2.2 Surface Tension 16
2.1.2.3 Viscosity 16
2.1.2.4 Particle Size 17
2.2 Conductive Inks 17
2.2.1 Metallic Nanoparticle Inks 17
2.2.2 FunctionalizedMultiwalled Carbon Nanotube (f-MWCNT) Inks 20
2.2.2.1 Introduction 20
2.2.2.2 MWCNT Ink Formulation 21
2.2.2.3 Resistance Characterization 23
2.2.3 MWCNT/Polyaniline Composite Inks 25
2.2.3.1 Introduction 25
2.2.3.2 Composite Synthesis 26
2.2.3.3 Characterization ofWater-dispersible MWCNT/PANI Composite 28
2.3 Semiconductor Inks 33
2.3.1 Organic Semiconductor Inks 33
2.3.2 Single-walled Carbon Nanotube (SWCNT) Inks 36
2.3.2.1 SWCNTs in Organic Solvents 37
2.3.2.2 SWCNTs inWater 38
2.3.2.3 SWCNT/Polymer Composite 39
2.3.3 SWCNT/Polymer Composites Inks 42
2.4 Summary 43
References 43
Part II Printed Electronic Building Blocks 53
3 Printed Thin-film Transistors (TFTs) and Logic Circuits 55
3.1 Introduction 55
3.1.1 TFTs Versus Silicon MOSFETs 55
3.1.2 State-of-the-art TFT Technologies 56
3.1.3 New TFT Technologies 58
3.2 TFT Structure and Operation 60
3.2.1 TFT Architectures 60
3.2.2 Electrical Characteristics of TFTs 62
3.2.2.1 Carrier Mobility (𝜇) 62
3.2.2.2 On/Off Ratio (Ion/Ioff) 63
3.2.2.3 Threshold Voltage (Vt) 63
3.2.2.4 Sub-threshold Swing (SS) 64
3.3 Printed TFTs: an Overview 64
3.4 Carbon Nanotube (CNT)-network TFTs 71
3.4.1 Challenges in CNT-network TFTs 71
3.4.2 Percolation Transport in Nanotube Networks 73
3.4.3 Solution-process Fabrication of CNT-TFTs 75
3.4.4 Electrical Performance Enhancement in CNT-TFTs 76
3.4.4.1 Hysteresis Suppression 76
3.4.4.2 High 𝜇 and Large Ion/Ioff 79
3.4.4.3 Uniformity and Scalability 81
3.4.4.4 Ambient and Operational Stabilities 81
3.5 Logic Circuits Based on CNT-TFTs 82
3.6 Summary 84
References 85
4 Printed PassiveWireless Sensors 91
4.1 Introduction 91
4.2 Sensing Materials 92
4.2.1 Carbon Nanotube-based Sensors 92
4.2.2 FunctionalizedMultiwalled Carbon Nanotubes as Humidity Sensing Material 93
4.2.2.1 Humidity Sensing Properties 94
4.2.2.2 Humidity Sensing Mechanism 96
4.2.2.3 Mechanical Flexibility 98
4.3 Passive UHFWireless Sensor 99
4.3.1 Flexible UHF Humidity Sensor Based on Carbon Nanotube 99
4.3.1.1 Sensor Operation Principle 99
4.3.1.2 Flexible Humidity Sensor Demonstration 100
4.3.2 Sensor Optimization: Influence of Resistor-electrode Structure 101
4.3.3 AnalyticalModel of Interdigital Electrode Capacitance 104
4.3.3.1 Interdigital Electrode and Interdigital Capacitance 104
4.3.3.2 Modified AnalyticalModels of IDCs 105
4.4 Passive UWBWireless Sensor 108
4.4.1 Sensor Operation Principle 108
4.4.2 Theoretical Analysis and Data-processing Algorithm 109
4.4.2.1 Theoretical Analysis 109
4.4.2.2 Data-processing Algorithm 111
4.4.3 Sensor Prototype 112
4.4.4 Inkjet Printing of CoplanarWaveguide: Variable Ink-layer Thickness Approach 114
4.4.4.1 Introduction 114
4.4.4.2 Variable Ink-layer Thickness Approach 115
4.5 Summary 118
References 119
5 Printed RFID Antennas 125
5.1 Introduction 125
5.1.1 Evolution of RFID-enabled Ubiquitous Sensing 126
5.2 Future Trends and Challenges 126
5.2.1 Design Challenges for RFID Tag Antennas 127
5.3 RFID Antennas: Narrow Band 127
5.3.1 Progressive Meander Line Antennas 127
5.3.1.1 Antennas Design Evolution and Geometry 128
5.3.1.2 Antenna Fabrication Parameters 131
5.3.1.3 Parametric Analysis 132
5.4 RFID Antennas:Wideband 133
5.4.1 Bowtie Antenna: Rounded Corners with T-matching 133
5.4.1.1 Antenna Dimensions and Parametric Optimization 133
5.4.1.2 Field and Circuit Concepts Parametric Analysis 134
5.4.2 Bowtie Antenna: Square Hole-matching Technique 137
5.4.2.1 Antenna Design Numerical Analysis and Optimization 138
5.4.2.2 Effective Aperture of Antenna 138
5.4.2.3 Results, Discussion, and Analysis 140
5.5 RFID Antennas: Sensor Enabled 143
5.5.1 Archimedean Spiral Antenna 143
5.5.1.1 Manufacturing Parametric Analysis 145
5.5.1.2 Parametric Analysis of Field and Circuit Concepts 147
5.5.2 RFID Antenna with Embedded Sensor and Calibration Functions 149
5.5.2.1 Antenna as a Sensor Design 150
5.6 Summary 152
References 152
6 Printed Chipless RFID Tags 157
6.1 Introduction 157
6.1.1 RFID History 157
6.1.2 RFID System 158
6.1.3 RFID Advantages 161
6.1.4 RFID Applications 162
6.1.4.1 Logistics 162
6.1.4.2 Healthcare 163
6.1.4.3 Retail 163
6.1.4.4 Manufacturing 163
6.1.4.5 Transportation 163
6.1.4.6 Agriculture 163
6.1.5 RFID Challenges 164
6.2 Time-domain-based RFID Tags 166
6.3 Frequency-domain-based RFID Tags 171
6.4 Printing of Chipless RFID Tags 172
6.4.1 Printing of Time-domain RFID Tags 172
6.4.2 Printing of Frequency Domain Chipless RFID Tags 175
6.5 Summary 178
6.5.1 Large Coding Capacity 179
6.5.2 Compact Size 179
6.5.3 Configurability 179
References 180
Part III SystemIntegration for Printed Electronics 183
7 Heterogeneous Integration of Silicon and Printed Electronics 185
7.1 Introduction 185
7.2 Inkjet-printed Interconnections 186
7.2.1 Inkjet Printing Technology 186
7.2.2 Electrical Performance and Morphology 188
7.2.3 Reliability Evaluation in 85 ∘C/85% RH Ambient 191
7.3 Heterogeneous Integration 192
7.3.1 Introduction of Traditional Integration Approach 192
7.3.2 Heterogeneous Integration Process 194
7.3.3 Electrical Performance of Heterogeneous Interconnects 198
7.3.4 Bendability of Heterogeneous Interconnects 200
7.4 Summary 201
References 201
8 Intelligent Packaging: Humidity Sensing System 205
8.1 Introduction 205
8.2 Plastic-based Humidity Sensor Box Prototype 207
8.2.1 Architecture of Humidity Sensor Box 207
8.2.2 f-MWCNT-based Resistive Humidity Sensor 208
8.2.3 System Integration 208
8.3 Paper-based Humidity Sensor Card Prototype 210
8.3.1 Fatigue of Interconnects versus Bending and Folding 211
8.3.1.1 Sample Fabrication and Experimental Setups 211
8.3.1.2 Fatigue Test Results and Discussion 212
8.3.2 Bendability of the Humidity Sensor 215
8.3.3 Demonstration of Humidity Sensor Cards 217
8.4 Summary 218
References 218
9 Wearable Healthcare Device: Bio-Patch 221
9.1 Introduction 221
9.2 System Overview 222
9.2.1 Bio-signals 223
9.2.2 Customized Bio-sensing Chip 225
9.2.3 Inkjet-printed Electrodes 226
9.3 Paper-based Bio-Patch 230
9.4 Polyimide-based Multi-channel Bio-Patch 230
9.5 Polyimide-based Miniaturized Bio-Patch 234
9.6 Summary 239
References 239
10 Life Cycle Assessment (LCA) for Printed Electronics 243
10.1 Introduction 243
10.2 Analysis Methodology 246
10.3 Environmental Footprint 252
10.4 Sustainable Production of Polymer- and Paper-based RFID Antennas 258
10.5 Summary 264
References 265
Index 269
