Unconventional Nanopatterning Techniques and Applications

John A. Rogers, PhD, holds the Lee J. Flory-Founder Chair in the College of Engineering at the University of Illinois at Urbana-Champaign. He was selected as one of the Top 50 Research Leaders by Scientific American. Dr. Rogers has authored more than 200 papers and holds nearly sixty patents. Hong H. Lee, PhD, is a Professor in the School of Chemical and Biological Engineering at the Seoul National University, Korea. He is the author of more than 200 papers and two books.

• PREFACE xvI NANOPATTERNING TECHNIQUES 11 INTRODUCTION 32 MATERIALS 72.1 Introduction 72.2 Mold Materials and Mold Preparation 82.2.1 Soft Molds 82.2.2 Hard Molds 192.2.3 Rigiflex Molds 192.3 Surface Treatment and Modification 21References 233 PATTERNING BASED ON NATURAL FORCE 273.1 Introduction 273.2 Capillary Force 283.2.1 Open-Ended Capillary 293.2.2 Closed Permeable Capillary 313.2.3 Completely Closed Capillary 403.2.4 Fast Patterning 433.2.5 Capillary Kinetics 453.3 London Force and Liquid Filament Stability 483.3.1 Patterning by Selective Dewetting 493.3.2 Liquid Filament Stability: Filling and Patterning 513.4 Mechanical Stress: Patterning of A Metal Surface 56References 634 PATTERNING BASED ON WORK OF ADHESION 674.1 Introduction 674.2 Work of Adhesion 684.3 Kinetic Effects 714.4 Transfer Patterning 744.5 Subtractive Transfer Patterning 794.6 Transfer Printing 82References 915 PATTERNING BASED ON LIGHT: OPTICAL SOFT LITHOGRAPHY 955.1 Introduction 955.2 System Elements 965.2.1 Overview 965.2.2 Elastomeric Photomasks 965.2.3 Photosensitive Materials 995.3 Two-Dimensional Optical Soft Lithography (OSL) 1005.3.1 Two-Dimensional OSL with Phase Masks 1005.3.2 Two-Dimensional OSL with Embossed Masks 1045.3.3 Two-Dimensional OSL with Amplitude Masks 1055.3.4 Two-Dimensional OSL with AmplitudePhase Masks 1095.4 Three-Dimensional Optical Soft Lithography 1105.4.1 Optics 1115.4.2 Patterning Results 1125.5 Applications 1175.5.1 Low-Voltage Organic Electronics 1175.5.2 Filters and Mixers for Microfluidics 1185.5.3 High Energy Fusion Targets and Media for Chemical Release 1185.5.4 Photonic Bandgap Materials 120References 1226 PATTERNING BASED ON EXTERNAL FORCE: NANOIMPRINT LITHOGRAPHY 129L. Jay Guo6.1 Introduction 1296.2 NIL MOLD 1336.2.1 Mold Fabrication 1336.2.2 Mold Surface Preparation 1376.2.3 Flexible Fluoropolymer Mold 1376.3 NIL Resist 1386.3.1 Thermoplastic Resist 1396.3.2 Copolymer Thermoplastic Resists 1416.3.3 Thermal-Curable Resists 1426.3.4 UV-Curable Resist 1466.3.5 Other Imprintable Materials 1486.4 The Nanoimprint Process 1496.4.1 Cavity Fill Process 1496.5 Variations of NIL Processes 1526.5.1 Reverse Nanoimprint 1526.5.2 Combined Nanoimprint and Photolithography 1556.5.3 Roll-to-Roll Nanoimprint Lithography (R2RNIL) 1566.6 Conclusion 159References 1607 PATTERNING BASED ON EDGE EFFECTS: EDGE LITHOGRAPHY 167Matthias Geissler, Joseph M. McLellan, Eric P. Lee and Younan Xia7.1 Introduction 1677.2 Topography-Directed Pattern Transfer 1697.2.1 Photolithography with Phase-Shifting Masks 1707.2.2 Use of Edge-Defined Defects in SAMs 1727.2.3 Controlled Undercutting 1757.2.4 Edge-Spreading Lithography 1767.2.5 Edge Transfer Lithography 1787.2.6 Step-Edge Decoration 1807.3 Exposure of Nanoscale Edges 1817.3.1 Fracturing of Thin Films 1827.3.2 Sectioning of Encapsulated Thin Films 1827.3.3 Thin Metallic Films along Sidewalls of Patterned Stamps 1847.3.4 Topographic Reorientation 1867.4 Conclusion and Outlook 187References 1888 PATTERNING WITH ELECTROLYTE: SOLID-STATE SUPERIONIC STAMPING 195Keng H. Hsu, Peter L. Schultz, Nicholas X. Fang, and Placid M. Ferreira8.1 Introduction 1958.2 Solid-State Superionic Stamping 1978.3 Process Technology 1998.4 Process Capabilities 2038.5 Examples of Electrochemically Imprinted Nanostructures Using the S4 Process 208Acknowledgments 211References 2119 PATTERNING WITH GELS: LATTICE-GAS MODELS 215Paul J. Wesson and Bartosz A. Grzybowski9.1 Introduction 2159.2 The RDF Method 2189.3 Microlenses: Fabrication 2189.4 Microlenses: Modeling Aspects 2209.4.1 Modeling Using PDEs 2209.4.2 Modeling Using Lattice-Gas Method 2219.5 RDF at the Nanoscale 2229.5.1 Nanoscopic Features from Counter-Propagating RD Fronts 2229.5.2 Failure of Continuum Description 2259.5.3 Lattice-Gas Models at the Nanoscale 2279.6 Summary and Outlook 229References 23010 PATTERNING WITH BLOCK COPOLYMERS 233Jia-Yu Wang, Wei Chen, and Thomas P. Russell10.1 Introduction 23310.2 Orientation 23510.2.1 Self-Assembling 23510.2.2 Self-Directing 24710.3 Long-Range 25410.3.1 Solvent Annealing 25410.3.2 Graphoepitaxy 25610.3.3 Sequential, Orthogonal Fields 26010.4 Nanoporous BCP Films 26210.4.1 Ozonolysis 26410.4.2 Thermal Degradation 26410.4.3 UV Degradation 26710.4.4 Selective Extraction 27110.4.5 “Soft” Chemical Etch 27210.4.6 Cleavable Junction 27210.4.7 Solvent-Induced Film Reconstruction 274References 27611 PERSPECTIVE ON APPLICATIONS 291II APPLICATIONS 29312 SOFT LITHOGRAPHY FOR MICROFLUIDIC MICROELECTROMECHANICAL SYSTEMS (MEMS)AND OPTICAL DEVICES 295Svetlana M. Mitrovski, Shraddha Avasthy, Evan M. Erickson, Matthew E. Stewart, John A. Rogers, and Ralph G. Nuzzo12.1 Introduction 29512.2 Microfluidic Devices for Concentration Gradients 29712.3 Electrochemistry and Microfluidics 30012.4 PDMS and Electrochemistry 30212.5 Optics and Microfluidics 30612.6 Unconventional Soft Lithographic Fabrication of Optical Sensors 314Acknowledgments 317References 31813 UNCONVENTIONAL PATTERNING METHODS FOR BIONEMS 325Pilnam Kim, Yanan Du, Ali Khademhosseini, Robert Langer, and Kahp Y. Suh13.1 Introduction 32513.2 Fabrication of Nanofluidic System for Biological Applications 32613.2.1 Unconventional Methods for Fabrication of Nanochannel 32613.2.2 Application of Nanofluidic System 33213.3 Fabrication of Biomolecular Nanoarrays for Biological Applications 33813.3.1 DNA Nanoarray 33813.3.2 Protein Arrays 34013.3.3 Lipid Array 34513.4 Fabrication of Nanoscale Topographies for Tissue Engineering Applications 34713.4.1 Nanotopography-Induced Changes in Cell Adhesion 34713.4.2 Nanotopography-Induced Changes in Cell Morphology 348References 34914 MICRO TOTAL ANALYSIS SYSTEM 359Yuki Tanaka and Takehiko Kitamori14.1 Introduction 35914.1.1 Historical Backgrounds 35914.2 Fundamentals on Microchip Chemistry 36114.2.1 Characteristics of Liquid Microspace 36114.2.2 Liquid Handling 36214.2.3 Concepts of Micro Unit Operation and Continuous-Flow Chemical Processing 36214.3 Key Technologies 36514.3.1 Fabrication of Microchips 36514.3.2 Patterning for Fluid Control 36614.3.3 Detection 36614.4 Applications 36814.4.1 Synthesis 36814.4.2 Cell Adhesion Control 36914.4.3 Liquid Handling: Valve Using Wettability 370References 37215 COMBINATIONS OF TOP-DOWN AND BOTTOM-UP NANOFABRICATION TECHNIQUES AND THEIR APPLICATION TO CREATE FUNCTIONAL DEVICES 379Pascale Maury, David N. Reinhoudt, and Jurriaan Huskens15.1 Introduction 37915.2 Top-Down and Bottom-Up Techniques 38015.2.1 Top-Down Techniques 38015.2.2 Bottom-Up Techniques 38315.2.3 Mixed Techniques 38415.3 Combining Top-Down and Bottom-Up Techniques for High Resolution Patterning 38515.3.1 Top-Down Nanofabrication and Polymerization 38615.3.2 Top-Down Nanofabrication and Micelles 38715.3.3 Top-Down Nanofabrication and Block Copolymer Assembly 38715.3.4 Top-Down Nanofabrication and NP Assembly 38915.3.5 Top-Down Nanofabrication and Layer-by-Layer Assembly 39215.4 Applicaion of Combined Top-Down and Bottom-Up Nanofabrication for Creating Functional Devices 39715.4.1 Photonic Crystal Devices 39715.4.2 Protein Assays 400References 40616 ORGANIC ELECTRONIC DEVICES 41916.1 Introduction 41916.2 Organic Light-Emitting Diodes 42016.3 Organic Thin Film Transistors 429References 43917 INORGANIC ELECTRONIC DEVICES 44517.1 Introduction 44517.2 Inorganic Semiconductor Materials for Flexible Electronics 44617.2.1 “Bottom-Up” Approaches 44717.2.2 “Top-Down” Approaches 44917.3 Soft Lithography Techniques for Generating Inorganic Electronic Systems 45217.3.1 Micromolding in Capillaries 45317.3.2 Imprint Lithography 45417.3.3 Dry Transfer Printing 45417.4 Fabrication of Electronic Devices 45917.4.1 Transistors on Rigid Substrates via MIMIC Processing 45917.4.2 Flexible Inorganic Transistors 45917.4.3 Flexible Integrated Circuits 46317.4.4 Heterogeneous Electronics 46617.4.5 Stretchable Electronics 469References 47518 MECHANICS OF STRETCHABLE SILICON FILMS ON ELASTOMERIC SUBSTRATES 483Hanqing Jiang, Jizhou Song, Yonggang Huang, and John A. Rogers18.1 Introduction 48318.2 Buckling Analysis of Stiff Thin Ribbons on Compliant Substrates 48418.3 Finite-Deformation Buckling Analysis of Stiff Thin Ribbons on Compliant Substrates 48818.4 Edge Effects 49518.5 Effect of Ribbon Width and Spacing 49818.6 Buckling Analysis of Stiff Thin Membranes on Compliant Substrates 50218.6.1 One-Dimensional Buckling Mode 50418.6.2 Checkerboard Buckling Mode 50618.6.3 Herrington Buckling Mode 50618.7 Precisely Controlled Buckling of Stiff Thin Ribbons on Compliant Substrates 50718.8 Concluding Remarks 512Acknowledgments 512References 51219 MULTISCALE FABRICATION OF PLASMONIC STRUCTURES 515Joel Henzie, Min H. Lee, and Teri W. Odom19.1 Introduction 51519.1.1 Brief Primer on Surface Plasmons 51719.1.2 Conventional Methods to Plasmonic Structures 51819.2 Soft Lithography and Metal Nanostructures 51819.3 A Platform for Multiscale Patterning 52019.3.1 Soft Interference Lithography: Patterns on a Nanoscale Pitch 52019.3.2 Phase-Shifting Photolithography: Patterns on a Microscale Pitch 52019.3.3 PEEL: Transferring Photoresist Patterns to Plasmonic Materials 52119.4 Subwavelength Arrays of Nanoholes: Plasmonic Materials 52219.4.1 Infinite Arrays of Nanoholes 52319.4.2 Finite Arrays (Patches) of Nanoholes 52519.5 Microscale Arrays of Nanoscale Holes 52619.6 Plasmonic Particle Arrays 52819.6.1 Metal and Dielectric Nanoparticles 52819.6.2 Anisotropic Nanoparticles 53119.6.3 Pyramidal Nanostructures 531Acknowledgments 533References 53320 A RIGIFLEX MOLD AND ITS APPLICATIONS 539Se-Jin Choi, Tae-Wan Kim, and Seung-Jun Baek20.1 Introduction 53920.2 Modulus-Tunable Rigiflex Mold 54020.3 Applications of Rigiflex Mold 54420.3.1 From Nanoimprint to Microcontact Printing 54420.3.2 Rapid Flash Patterning for Residue-Free Patterning 54720.3.3 Continuous Rigiflex Imprinting 54920.3.4 Soft Molding Application 55320.3.5 Capillary Force Lithography Applications 55620.3.6 Transfer Fabrication Technique 558References 56121 NANOIMPRINT TECHNOLOGY FOR FUTURE LIQUID CRYSTAL DISPLAY 565Jong M. Kim, Hwan Y. Choi, Moon-G. Lee, Seungho Nam, Jin H. Kim, Seongmo Whang, Soo M. Lee, Byoung H. Cheong, Hyuk Kim, Ji M. Lee, and In T. Han21.1 Introduction 56521.2 Holographic LGP 56921.2.1 Design and Properties of Holographic LGP 57021.2.2 NI Technology for the Holographic LGP 57221.3 Polarized LGP 57321.3.1 Design and Properties of Polarized LGP 57421.3.2 Fabrication of the Polarized LGP 57521.3.3 Optical Performance of the Polarized LGP 57621.4 Reflective Polarizer: Wire Grid Polarizer 57921.4.1 Design and Properies of WGP 58021.4.2 Fabrication and Applications 58121.5 Transflective Display 58521.5.1 Design and Optical Properties of Reflecting Pattern 58721.5.2 Fabrication of the Reflecting Pattern 588References 592INDEX 595