Emphasizing the fundamentals of transport phenomena, this book provides researchers and practitioners with the technical background they need to understand laser-induced microfabrication and materials processing at small scales. It clarifies the laser/materials coupling mechanisms, and discusses the nanoscale confined laser interactions that constitute powerful tools for top-down nanomanufacturing. In addition to discussing key and emerging applications to modern technology, with particular respect to electronics, advanced topics such as the use of lasers for nanoprocessing and nanomachining, the interaction with polymer materials, nanoparticles and clusters, and the processing of thin films are also covered.
Author(s): Costas P. Grigoropoulos
Edition: 1
Publisher: Cambridge University Press
Year: 2009
Language: English
Pages: 414
Tags: Специальные дисциплины;Наноматериалы и нанотехнологии;Технологии получения наноматериалов и наноструктур;
Cover......Page 1
Half-title......Page 3
Title......Page 5
Copyright......Page 6
Dedication......Page 7
Contents......Page 9
Preface......Page 13
1.1.1 Electric and magnetic properties of materials......Page 15
1.1.2 Boundary conditions......Page 16
1.1.3 Energy density and energy flux......Page 18
1.1.4 Wave equations......Page 19
1.1.5 Electromagnetic theory of absorptive materials......Page 22
Perfect dielectric media......Page 25
Reflection at the surface of an absorbing medium......Page 28
1.1.8 Laser light absorption in multilayer structures......Page 31
The Lorentz model for nonconductors......Page 35
The Drude model for conductors......Page 37
Crystalline Silicon......Page 41
Amorphous silicon and polysilicon......Page 44
Liquid silicon......Page 45
2.1.1 Continuous-wave – millisecond – microsecond lasers......Page 47
2.1.2 Nanosecond lasers......Page 48
2.1.4 Femtosecond lasers......Page 49
2.2.1 CO2 lasers......Page 50
2.2.3 Excimer lasers......Page 51
2.2.4 Nd:YAG lasers......Page 52
2.3.1 Light amplification......Page 53
2.3.2 Circular Gaussian beams in a homogeneous medium......Page 54
2.3.4 Higher-order beams......Page 56
2.3.6 Resonance frequencies of optical resonators......Page 57
2.3.7 Spectral characteristics of laser emission......Page 58
2.3.8 Q-Switching......Page 60
2.3.9 Mode-locking......Page 61
2.4.1 Gaussian beams......Page 62
2.4.3 Pulsed laser beams......Page 63
2.5 Optical components......Page 64
2.6.1 Gaussian beam focusing......Page 65
2.6.2 Beam shaping and homogenization......Page 68
2.6.4 Beam profile and power......Page 70
References......Page 72
3.1.1 Energy absorption......Page 74
3.2 Conductive heat transfer......Page 75
3.2.1 Scanning a beam over a semi-infinite substrate......Page 76
3.2.2 One-dimensional heat conduction......Page 78
3.2.2 Beams of circular cross section......Page 81
3.2.3 Gaussian laser beams......Page 82
3.2.4 Beam motion–quasi-static thermal field......Page 83
Quasi-static solution for an elliptic beam profile......Page 84
Scanning beam over a substrate of finite thickness......Page 85
3.3.1 Interface boundary conditions......Page 86
3.3.2 The enthalpy formulation......Page 87
3.3.4 Departures from equilibrium at the melt interface......Page 88
3.4 Ablative material removal......Page 89
3.4.1 Surface vaporization......Page 90
3.4.2 Knudsen-layer effects......Page 92
3.4.3 Explosive phase-change......Page 95
References......Page 99
4.1.1 Statistical mechanics......Page 101
4.1.2 Collisional processes in the plume......Page 103
Scanning mass analyzers......Page 104
Time-of-flight mass spectrometers......Page 105
Laser mass spectrometry......Page 109
4.3.2 The role of electronic excitations......Page 110
4.3.3 The effect of topography development......Page 117
References......Page 122
5.1 Introduction......Page 123
5.2.1 Relaxation in plasmas......Page 125
Absorption due to free–free transitions......Page 126
The total spectral coefficient of absorption......Page 127
5.2.3 High-irradiance ablation......Page 129
5.3.1 The Euler equation for the dynamics of a compressible gas......Page 130
5.3.2 Molecular-dynamics models......Page 132
5.4.1 Probe-beam-deflection diagnostics......Page 136
5.4.2 Absorption and emission spectroscopy......Page 138
5.4.3 Laser-induced fluorescence spectroscopy......Page 139
5.4.4 Plume interactions with background gas......Page 140
5.5 Picosecond-laser plasmas......Page 147
5.5.1 Fundamentals of picosecond-laser plasmas......Page 148
References......Page 156
6.1 Introduction......Page 160
6.2.1 The relaxation-time approximation and two-step models......Page 161
6.2.2 Two-step models......Page 164
6.2.3 Detailed modeling of collisional events......Page 167
6.3 Femtosecond-laser interaction with semiconductor materials......Page 172
6.4.1 Melting of crystalline silicon......Page 174
6.4.2 Femtosecond-laser ablation of crystalline silicon......Page 180
6.5 Generation of highly energetic particles......Page 182
6.6 Ultrafast phase explosion......Page 186
6.7 Nonlinear absorption and breakdown in dielectric materials......Page 190
6.7.1 Carrier excitation, photo-ionization, and avalanche ionization......Page 191
Self-focusing and self-phase modulation......Page 195
6.7.3 Defect generation......Page 196
Exciton self-trapping......Page 197
Origins of intrinsic defects......Page 198
Imaging experiments......Page 200
Interferometry experiments......Page 202
Self-focusing and defocusing......Page 206
Spatial splitting......Page 207
Temporal splitting......Page 208
6.8 Application in the micromachining of glass......Page 209
References......Page 211
7.1 Modeling of energy absorption and heat transfer in pulsed-laser irradiation of thin semitransparent films......Page 216
7.2 Continuous-wave (CW) laser annealing......Page 217
7.3 Inhomogeneous semiconductor-film melting......Page 219
7.4.1 Explosive recrystallization......Page 223
7.4.2 Interface kinetics......Page 224
7.4.3 Experimental diagnostics......Page 226
7.4.4 Recrystallization of poly-silicon versus amorphous silicon......Page 230
7.5 Nucleation in the supercooled liquid......Page 231
7.6 Lateral crystal growth induced by spatially modified irradiation......Page 236
7.7 Mass transfer and shallow doping......Page 245
References......Page 250
8.1 Hydrodynamic stability of transient melts......Page 254
8.2.1 Introduction......Page 259
8.2.2 An approximate analytical model......Page 260
8.2.3 Computational modeling of capillary-driven surface modification......Page 263
Photothermal deflection......Page 264
Photoelectron imaging......Page 267
8.3.2 An analytical model......Page 270
8.3.3 Detailed numerical modeling......Page 273
References......Page 278
9.2 Fundamental processes......Page 279
9.2.1 Photothermal processes......Page 281
9.2.2 Photochemical processes......Page 283
9.2.3 Interplay between photochemical and photothermal processes......Page 285
9.3 Applications......Page 287
9.3.1 Laser fabrication of polymers......Page 288
9.3.2 MALDI......Page 289
9.3.3 Laser–tissue interactions......Page 290
References......Page 293
10.1.1 Background......Page 296
10.1.2 Temperature measurement......Page 298
10.1.3 Pressure production......Page 301
10.1.4 Kinetics of vapor phase change......Page 304
10.2.1 Backgound......Page 306
10.2.2 Optical generation of acoustic transients......Page 309
10.2.3 Numerical modeling of explosive vaporization......Page 314
10.2.4 Experimental results......Page 316
10.3.1 The rate equation for optical breakdown......Page 318
References......Page 324
11.1 Introduction......Page 327
11.2 Adhesion forces......Page 328
11.2.1 The van der Waals force......Page 329
11.2.2 The electrostatic force......Page 331
11.2.3 The capillary force......Page 332
11.3 A practical laser-cleaning system......Page 333
11.4 Mechanisms of laser cleaning......Page 335
11.4.1 Dry laser cleaning......Page 336
In situ monitoring and visualization......Page 338
Enhancement of cleaning efficiency by pressure generation......Page 339
References......Page 343
12.1.1 The classical Mie solution for a spherical particle......Page 344
12.1.3 Effective-medium theory......Page 345
12.2.1 Size-dependent depression of the melting point......Page 347
12.2.2 Ultrafast-laser interactions with nanoparticles......Page 349
12.3.1 Ablation of solid targets......Page 353
12.3.2 Ablation in aqueous solutions......Page 356
12.3.3 Ablation of consolidated particles......Page 359
References......Page 363
13.1 Laser chemical vapor deposition......Page 364
13.2.1 Laser-induced forward transfer......Page 369
13.2.2 MAPLE-assisted direct writing......Page 373
13.3.2 Hybrid microprinting and laser sintering of nanoparticle suspensions......Page 375
13.3.1 Photoinitiation and photopolymerization......Page 382
13.3.2 Projection microstereolithography......Page 384
13.3.3 Two-photon photopolymerization and three-dimensional lithographic microfabrication......Page 386
References......Page 389
14.1 Introduction......Page 390
14.2 Apertureless NSOM nanomachining......Page 391
14.2.2 The temperature distribution......Page 392
14.2.4 The mechanism of surface nanostructuring......Page 394
14.3 Apertured NSOM nanomachining......Page 397
14.4 Nanoscale melting and crystallization......Page 400
14.5 Laser-assisted NSOM chemical processing......Page 403
14.6 Plasmas formed by near-field laser ablation......Page 406
14.7 Outlook......Page 410
References......Page 411
Index......Page 413
