Cover 1
Nanolithography: The art of fabricating nanoelectronic and nanophotonic devices and systems 4
Copyright 5
Contents 6
Contributor contact details 14
Woodhead Publishing Series in Electronic and Optical Materials 18
Preface 24
1: Optical projection lithography 26
1.1 Introduction 26
1.2 Lithography technology and trends 26
1.3 Fundamentals of optical lithography 30
1.4 Image evaluation 33
1.5 Projection lithography systems 38
1.6 Wavelengths for optical lithography 47
1.7 Lithography in the deep ultraviolet (UV) 48
1.8 Resolution enhancement technology 52
1.9 Immersion lithography 61
1.10 Multiple patterning optical lithography 63
1.11 Conclusion 65
1.12 References 65
2: Extreme ultraviolet (EUV) lithography 67
2.1 Introduction 67
2.2 EUV sources 77
2.3 EUV optics 83
2.4 EUV masks 87
2.5 EUV resists 95
2.6 EUV integration and implementation challenges 98
2.7 Conclusion and future trends 100
2.8 Acknowledgments 101
2.9 References 102
3: Electron beam lithography 105
3.1 Introduction 105
3.2 Using pixel parallelism to address the throughput bottleneck 109
3.3 The tradeoff between resolution and throughput 121
3.4 Distributed systems 125
3.5 Ultimate lithographic resolution 129
3.6 Electron-beam patterning of photomasks for optical lithography 132
3.7 Conclusion 135
3.8 Acknowledgements 136
3.9 References 136
4: Focused ion beams for nano-machining and imaging 141
4.1 Introduction 141
4.2 An adumbrated history of focused ion beams (FIBs) 143
4.3 Sources of ions: a quartet of types 144
4.4 Charged particle optics 150
4.5 Ion-matter interactions 153
4.6 Milling 163
4.7 Deposition 170
4.8 Imaging 172
4.9 Spectroscopy 178
4.10 Conclusion and future trends 178
4.11 References 180
5: Masks for microand nanolithography 183
5.1 Introduction 183
5.2 Mask materials 187
5.3 Mask process 192
5.4 Mask metrology 193
5.5 Defects and masks 197
5.6 Conclusion 202
5.7 References 203
6: Maskless photolithography 204
6.1 Introduction 204
6.2 The use of photons as opposed to charged particles 205
6.3 Forms of maskless photolithography 206
6.4 Zone-plate-array lithography (ZPAL) 208
6.5 Proximity-effect correction 211
6.6 Extending the resolution of ZPAL 212
6.7 Commercialization of ZPAL by LumArray, Inc. 214
6.8 Conclusion 216
6.9 References 217
7: Chemistry and processing of resists for nanolithography 219
7.1 Introduction 219
7.2 Resists for optical lithography: synthesis and radiation induced chemistry of resists as a function of exposure technology 225
7.3 Chemically amplified resist process considerations 240
7.4 Chemically amplified resists for 193 nm lithography 242
7.5 Resists for extreme ultraviolet lithography (EUVL) 256
7.6 Resists for electron beam lithography 259
7.7 Resists for selected forward looking lithographic technologies 290
7.8 Resist resolution limitations 293
7.9 Conclusion 295
7.10 References 296
8: Directed assembly nanolithography 312
8.1 Introduction 312
8.2 Block copolymers in lithography 312
8.3 Directed self-assembly of block copolymers 319
8.4 Programmable three-dimensional lithography 327
8.5 Conclusion 335
8.6 References 336
9: Nanoimprint lithography 340
9.1 Introduction 340
9.2 An overview of imprint lithography 345
9.3 Soft lithography 346
9.4 Thermal imprint lithography 347
9.5 Alternative thermal imprint processes 352
9.6 Ultraviolet (UV) nanoimprint lithography overview 355
9.7 Jet and flash imprint lithography 356
9.8 Roll to roll imprint lithography 365
9.9 Defectivity 367
9.10 Conclusions 369
9.11 Acknowledgments 370
9.12 References 370
10: Nanostructures: fabrication and applications 373
10.1 Introduction 373
10.2 Characterization of nanostructures 375
10.3 Methods to create nanostructures: top-down fabrication of nanostructures 375
10.4 Methods to create nanostructures: bottom-up fabrication of nanostructures 383
10.5 Properties of nanostructures 389
10.6 Applications of nanostructures 395
10.7 References 396
11: Nanophotonics: devices for manipulating light at the nanoscale 401
11.1 Introduction 401
11.2 Photonic crystals 402
11.3 Ring resonators 404
11.4 Extraordinary optical transmission through subwavelength apertures 407
11.5 Optical nanoantennas 409
11.6 Plasmonic focusing 412
11.7 Near-field optical microscopy 415
11.8 Plasmonic waveguides 417
11.9 Enhancement of nonlinear processes 418
11.10 Application in photovoltaics 420
11.11 Conclusion 420
11.12 References 421
12: Nanodevices: fabrication, prospects for low dimensional devices and applications 424
12.1 Introduction 424
12.2 Motivation for nanodevices 426
12.3 Nanofabrication: creating the building blocks for devices 428
12.4 Prospects for low dimensional devices 433
12.5 Beyond the bottom-up: hybrid nanoelectronics 438
12.6 Conclusion and future trends 442
12.7 References 442
13: Microfluidics: technologies and applications 449
13.1 Introduction 449
13.2 Current trends in microfluidics 450
13.3 Present state of technology 454
13.4 Applications 459
13.5 Future trends 461
13.6 Conclusion 465
13.7 Sources of further information and advice 465
13.8 References 466
14: Modeling of nanolithography processes 469
14.1 Introduction 469
14.2 Optical lithography modeling 470
14.3 The optical system in optical lithography modeling 474
14.4 Photoresist model 478
14.5 Model critical dimension (CD) extraction 479
14.6 Difficulties in modeling 480
14.7 Extreme ultraviolet (EUV)/electron beam lithography modeling 482
14.8 Conclusion 487
14.9 References 487
15: Mask-substrate alignment via interferometric moir é fringes 491
15.1 Introduction 491
15.2 Background to alignment methods 492
15.3 Fundamentals of interferometricspatial phase imaging (ISPI) 497
15.4 Implementation of moiré 500
15.5 Characteristics of moir é fringe formation 504
15.6 Performance of ISPI 519
15.7 Backside ISPI 522
15.8 Conclusion and future trends 525
15.9 References 526
16: Sidewall roughness in nanolithography: origins, metrology and device effects 528
16.1 Introduction 528
16.2 Metrology and characterization 530
16.3 Process and material effects: modeling and simulation 538
16.4 Process and material effects: experimental results 540
16.5 Impact on device performance 548
16.6 Conclusions 555
16.7 References 557
17: New applications and emerging technologies in nanolithography 563
17.1 Introduction 563
17.2 Applications of high-resolution patterning to new device structures: advances in tunneling structures 566
17.3 Geometry control of the tunnel junctions 568
17.4 The quantum dot placement problem 572
17.5 Conclusion 573
17.6 Acknowledgments 574
17.7 References 574
Index 576