Part 1 book “Flexible and stretchable medical devices” has contents: History of flexible and stretchable devices, carbon nanotube based flexible and stretchable electronics, organic-based transistors and sensors, printed transistors and sensors, flexible photovoltaic systems,… and other contents.
Flexible and Stretchable Medical Devices Flexible and Stretchable Medical Devices Edited by Kuniharu Takei Editor Prof Kuniharu Takei Osaka Prefecture University Department of Physics and Electronics 1-1 Gakuen Nakaku Sakai 599-8531 Osaka Japan All books published by Wiley-VCH are carefully produced Nevertheless, authors, editors, and publisher not warrant the information contained in these books, including this book, to be free of errors Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate Cover credit: iStock shawn_hempel Library of Congress Card No.: applied for British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at © 2018 Wiley-VCH Verlag GmbH & Co KGaA, Boschstr 12, 69469 Weinheim, Germany All rights reserved (including those of translation into other languages) No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers Registered names, trademarks, etc used in this book, even when not specifically marked as such, are not to be considered unprotected by law Print ISBN: 978-3-527-34183-2 ePDF ISBN: 978-3-527-80484-9 ePub ISBN: 978-3-527-80486-3 Mobi ISBN: 978-3-527-80487-0 oBook ISBN: 978-3-527-80485-6 Typesetting SPi Global, Chennai, India Printing and Binding Printed on acid-free paper v Contents Preface xiii History of Flexible and Stretchable Devices Kuniharu Takei References Carbon Nanotube Based Flexible and Stretchable Electronics Le Cai and Chuan Wang 2.1 2.2 Introduction Carbon Nanotube Networks for Applications in Flexible Electronics 10 Thin-Film Transistors (TFTs) 10 Integrated Circuits 11 Active Matrix Backplanes for Flexible Display, E-Skin and Imager 16 Carbon Nanotube Networks for Applications in Stretchable Electronics 19 Stretchable Conductors 21 Stretchable Strain Sensor 23 Stretchable Thin-Film Transistors 27 Scalable Fabrication Process—Printing 35 Digital Printing—Inkjet and Aerosol Jet 36 Gravure Printing 41 Printed Complementary Metal–Oxide Semiconductor (CMOS) Devices 41 Conclusions and Outlook 44 References 45 2.2.1 2.2.2 2.2.3 2.3 2.3.1 2.3.2 2.3.3 2.4 2.4.1 2.4.2 2.4.3 2.5 Organic-Based Transistors and Sensors 53 Aristide Gumyusenge, Tianbai Xu, Xiaozhi Wang, and Jianguo Mei 3.1 3.2 3.2.1 3.2.1.1 Introduction 53 Materials Consideration for Flexible Organic-Based Transistors How Flexibility is Achieved 54 Flexible Substrates 54 54 vi Contents 3.2.1.2 3.2.2 3.2.3 3.3 3.3.1 3.3.1.1 3.3.1.2 3.3.2 3.3.2.1 3.3.2.2 3.3.2.3 3.4 3.5 3.5.1 3.5.2 3.5.3 3.5.4 3.5.5 3.6 Flexible Electrodes 55 Organic Dielectric Layer 56 Organic Functional Layer 57 State-of-the-Art Designs and Fabrication of Organic-Based Transistors 57 Organic Field-Effect Transistors 58 Structure 58 Performance and Characterization 59 Modifications of OFETs for Sensing Applications 60 Electrolyte-Gated and Ion-Sensitive Organic Field-Effect Transistors 60 Organic Electrochemical Transistors 62 Operating Mechanisms 63 Fabrication Techniques for Organic-Based Transistors and Sensors 63 Flexible Organic Transistor-Based Sensors 65 Flexible Organic Strain Sensors 65 Flexible Organic Pressure Sensors 67 Flexible Organic Temperature Sensors 69 Flexible Organic Biosensors 70 Flexible Organic Optical Sensors 73 Summary and Outlook 74 References 75 83 Printed Transistors and Sensors Kenjiro Fukuda 4.1 4.2 4.2.1 4.2.2 4.2.3 4.3 4.3.1 4.3.2 4.3.3 4.3.3.1 4.3.3.2 4.3.4 4.3.5 4.4 Introduction 83 Printing Technologies for Electronics 84 Inkjet Printing 85 Gravure Printing 86 Reverse-Offset Printing for High-Resolution Patterning 87 Printed Transistors 88 Fabrication of Fully Printed Transistors 88 Profile Control of Inkjet-Printed Electrodes 89 Mechanical Stability 91 Calculation of Strain in the Devices 91 Improvement of Adhesion 91 Printed Organic Transistors with Uniform Electrical Performance 93 Ultraflexible and Fully Printed Organic Circuits 94 Printed Biosensors 97 References 99 Flexible Photovoltaic Systems 105 Lichen Zhao, Deying Luo, and Rui Zhu 5.1 5.1.1 5.1.2 Introduction 105 Introduction of Flexible Photovoltaics 105 Principles of Photovoltaics 106 Contents 5.1.3 5.1.3.1 5.1.3.2 5.1.4 5.2 5.2.1 5.2.2 5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.5 The Flexible Substrates 109 Metals and the Alloys 109 Polymers 110 The Types of Flexible Photovoltaic Systems 110 Flexible Inorganic Photovoltaic Systems 110 Flexible Silicon Photovoltaics 110 Flexible Copper Indium Gallium Selenide Photovoltaics 113 Flexible Organic Photovoltaic Systems 115 Fundamental Properties of OPV Materials 115 Device Structure and Working Mechanisms 116 Materials and Methods for OPV 118 Recent Advances in Flexible OPV 119 Flexible Organic–Inorganic Hybrid Photovoltaic Systems 122 Fundamental Properties of Perovskites 123 Device Structure and Working Mechanisms 124 Materials and Methods for Flexible PerSCs 125 Recent Advances for Flexible PerSCs 128 Summary and Conclusion 132 References 133 Materials Design for Flexible Thermoelectric Power Generators 139 Yoshiyuki Nonoguchi 6.1 6.2 6.2.1 6.2.2 6.2.3 Introduction 139 General Principles 140 The Basic Principles of Thermoelectricity 140 Density of State and the Seebeck Coefficient 141 Energy Conversion Efficiency and Dimensionless Thermoelectric Figure of Merit ZT 142 A Classical Requirement for Efficient Module Design 144 Thermoelectric Materials Design 145 Organic Solids and Conducting Polymers 145 Carbon Nanotubes and Related Matters 149 Useful Survey Methods for Discovering Efficient Thermoelectric Materials 154 Prototype Thermoelectric Generators and Applications 154 Outlook for Flexible Thermoelectric Generators 155 References 156 6.2.4 6.3 6.3.1 6.3.2 6.3.3 6.3.4 6.4 Flexible Supercapacitors Based on Two-Dimensional Materials 161 Dianpeng Qi and Xiaodong Chen 7.1 7.2 7.2.1 7.2.2 Introduction 161 Flexible Supercapacitors Based on 2D Materials 162 2D Electrode Materials for Flexible EDLCs 163 2D Materials for Pseudocapacitive Supercapacitors 171 vii viii Contents 7.2.3 7.3 2D Electrode Materials for Hybrid Flexible Supercapacitors 176 Conclusions 179 References 181 Organometal Halide Perovskites for Next Generation Fully Printed and Flexible LEDs and Displays 199 Thomas Geske, Sri Ganesh R Bade, Matt Worden, Xin Shan, Junqiang Li, and Zhibin Yu 8.1 8.1.1 8.1.2 8.1.3 8.2 8.3 8.4 Introduction 199 General Background for LEDs 200 Fundamentals of Halide Perovskites 201 Multilayer Perovskite LEDs 203 Single Layer Perovskite LEDs 206 Current Challenges 208 Conclusions and Outlook 211 Acknowledgments 211 References 211 Flexible Floating Gate Memory 215 Ye Zhou, Su-Ting Han, and Arul Lenus Roy Vellaisamy 9.1 9.2 9.3 9.3.1 9.3.2 9.3.3 9.4 9.5 9.6 9.7 Introduction 215 Device Operation of Floating Gate Memory 216 Charge Injection Mechanism in Floating Gate Memory 217 The Hot-electron Injection Mechanism 217 Fowler–Nordheim (F-N) Tunneling Mechanism 218 Direct Tunneling Mechanism 219 Flexible Nanofloating Gate Memory 219 Characterization of Floating Gate Memory 221 Flexibility of Floating Gate Memory 223 Conclusion 225 References 225 10 Flexible and Stretchable Wireless Systems 229 Aftab M Hussain and Muhammad M Hussain 10.1 10.2 10.2.1 10.2.2 10.2.3 10.3 10.3.1 10.3.2 10.4 10.4.1 10.4.2 10.5 Introduction 229 The Basics of Wireless Systems 230 Wireless Systems 230 Antennas 231 Antenna Parameters 233 Flexible, Stretchable Circuits 234 Flexible, Stretchable Silicon Circuits 234 Non-Silicon-Based Channels 236 Flexible Antennas 239 Micromachined Flexible Antennas 240 Inkjet-Printed Antennas 240 Stretchable Antennas 242 Contents 10.5.1 10.5.2 10.6 Material Stretchability 242 Design Stretchability 244 Future Outlook 246 References 247 11 Conductive Nanosheets for Ultra-Conformable Smart Electronics 253 Kento Yamagishi, Silvia Taccola, Shinji Takeoka, Toshinori Fujie, Virgilio Mattoli, and Francesco Greco 11.1 11.2 11.2.1 11.2.2 Introduction 253 Fabrication of Conductive Nanosheets 255 Spin-Coating-Processed Conductive Nanosheets 255 Roll-to-Roll (R2R) Gravure-Printing-Processed Conductive Nanosheets 258 Characterization of Conductive Nanosheets 260 Electrical Properties of Conductive Nanosheets 260 Structural Properties of Conductive Nanosheets 262 Mechanical Properties of Conductive Nanosheets 263 Electrochemical Properties of Conductive Nanosheets 267 Applications of Conductive Nanosheets 269 Surface Electromyogram (EMG) Recording Using Conductive Nanosheets 269 Humidity Sensors 272 Microactuators 272 Tattoo Conductive Nanosheets for Skin-Contact Applications 274 Concluding Remarks 277 Acknowledgments 278 References 278 11.3 11.3.1 11.3.2 11.3.3 11.3.4 11.4 11.4.1 11.4.2 11.4.3 11.4.4 11.5 12 Flexible Health-Monitoring Devices/Sensors 287 Minjeong Ha, Seongdong Lim, and Hyunhyub Ko 12.1 12.2 12.2.1 12.2.1.1 12.2.1.2 12.2.2 12.2.2.1 12.2.2.2 12.2.2.3 12.2.2.4 Introduction 287 Flexible Sensors for Health Monitoring 288 Detection Approaches for Physical Bio-Signals 289 Pressure and Strain Sensors for Health Monitoring 289 Temperature Sensors for Health Monitoring 293 Detection Approaches for Biochemical Signals 295 Flexible pH Sensors 297 Flexible Blood Sugar Sensors 299 Flexible Pulse Oximeters 299 Other Flexible Chemical Sensors to Detect Volatile Organic Compounds 302 Detection Approaches for Electrophysiological Signals 304 Multifunctional Flexible Sensors for Multiple Bio-Signals 306 Practical Applications of Flexible Health-Monitoring Devices 309 Sports and Fitness 309 Prosthetics and Rehabilitation 309 12.2.3 12.3 12.4 12.4.1 12.4.2 ix x Contents 12.4.3 12.4.4 12.5 Wound Therapy 311 Telemedicine and Self-Diagnosis of Disease Conclusions and Future Perspective 312 References 312 13 Stretchable Health Monitoring Devices/Sensors 323 Xian Huang 13.1 13.2 13.2.1 13.2.2 13.3 13.3.1 13.3.1.1 13.3.1.2 13.3.2 13.3.2.1 13.3.2.2 13.3.3 13.3.3.1 13.3.3.2 13.4 Introduction 323 Materials for Stretchable Health Monitoring Devices 323 Physically Soft and Stretchable Materials 324 Unique Stretchable Structures 324 Health Monitoring Applications of Stretchable Devices 326 Skin Sensors 326 Skin Biophysical Signal Monitoring 329 Biomolecule Analysis 332 Implantable Devices 336 Brain and Neural Probes 336 Cardiovascular Monitoring 337 Body Wearable Devices 337 Rehabilitation 337 Daily Health Tracking 341 Future of Stretchable Electronic Devices 341 References 342 14 Flexible/Stretchable Devices for Medical Applications 351 GwanJin Ko, JeongWoong Shin, and Suk-Won Hwang 14.1 14.2 Introduction 351 Materials, Synthesis and Composites for Flexible/Stretchable Systems 352 Electronic/Optoelectronic Devices, Sensors and Systems 355 Multifunctional Electronic Sensors and Power Scavenging Circuit for the Heart 358 Electrophysiology and Optogenetics for the Brain 362 Communication and Regulation for the Nervous System 364 Skin-Like Electronics/Optoelectronics 367 Transient, Bioresorbable Systems 370 Conclusion and Outlook 373 References 373 14.3 14.4 14.5 14.6 14.7 14.8 14.9 311 15 Implantable Flexible Sensors for Neural Recordings 381 Shota Yamagiwa, Hirohito Sawahata, and Takeshi Kawano 15.1 15.1.1 15.1.1.1 15.1.1.2 15.1.1.3 15.1.2 Introduction 381 Neuronal Signal Recordings EEG 383 ECoG 384 LFPs and Spikes 384 Electrode Materials 385 383 Contents 15.1.3 15.2 15.3 15.4 15.4.1 15.4.2 15.4.3 15.4.4 15.5 15.5.1 15.5.2 15.5.2.1 15.5.2.2 15.5.3 15.6 Electrode Impedance in Neural Recordings 385 Flexible Needle Electrodes 387 Flexible ECoG Electrodes 391 Functionalities of Flexible Substrates 395 Active Matrixes 395 Dissolvable Films 395 Stretchable Films 399 Other Functionalities 403 Flexible Devices for Chronic Applications 403 Tissue Damage 403 Packaging Technologies 405 Rivet-Like Electric and Mechanic Interconnections 405 Anisotropic Conductive Paste/Films 407 Wireless Technologies 407 Summary 407 References 408 16 Perspective in Flexible and Stretchable Electronics 411 Kuniharu Takei Index 413 xi ... 278 11 .3 11 .3 .1 11. 3.2 11 .3.3 11 .3.4 11 .4 11 .4 .1 11. 4.2 11 .4.3 11 .4.4 11 .5 12 Flexible Health-Monitoring Devices/Sensors 287 Minjeong Ha, Seongdong Lim, and Hyunhyub Ko 12 .1 12.2 12 .2 .1 12.2 .1. 1... Devices/Sensors 323 Xian Huang 13 .1 13.2 13 .2 .1 13.2.2 13 .3 13 .3 .1 13.3 .1. 1 13 .3 .1. 2 13 .3.2 13 .3.2 .1 13.3.2.2 13 .3.3 13 .3.3 .1 13.3.3.2 13 .4 Introduction 323 Materials for Stretchable Health Monitoring... 15 .1. 1 15 .1. 1 .1 15 .1. 1.2 15 .1. 1.3 15 .1. 2 Introduction 3 81 Neuronal Signal Recordings EEG 383 ECoG 384 LFPs and Spikes 384 Electrode Materials 385 383 Contents 15 .1. 3 15 .2 15 .3 15 .4 15 .4 .1 15.4.2 15 .4.3