Pulsed Laser Ablation of Solids: Basics, Theory and Applications (Springer Series in Surface Sciences Book 53)

The book introduces ‘the state of the art' of pulsed laser ablation and its applications. It is based on recent theoretical and experimental studies. The book reaches from the basics to advanced topics of pulsed laser ablation. Theoretical and experimental fundamental phenomena involved in pulsed laser ablation are discussed with respect to material properties, laser wavelength, fluence and intensity regime of the light absorbed linearly or non-linearly in the target material. The energy absorbed by the electrons leads to atom/molecule excitation, ionization and/or direct chemical bond breaking and is also transferred to the lattice leading to material heating and phase transitions. Experimental non-invasive optical methods for analyzing these phenomena in real time are described. Theoretical models for pulsed laser ablation and phase transitions induced by laser beams and laser-vapour/plasma interaction during the plume expansion above the target are also presented. Calculations of the ablation speed and dimensions of the ablated micro- and nano-structures are performed. The validity and required refinement of different models in different experimental conditions is provided. The pulsed laser deposition process which bases on collecting the ablated particles on a surface is analyzed in terms of efficiency and quality of the deposited films as a function of ambient conditions, target material, laser parameters and substrate characteristics. The interaction between the incident laser and the ablation plasma is analyzed with respect to its influence on the structures of the deposited films and its capacity to generate high harmonics and single attosecond pulses which are highly desirable in pump-probe experiments. Preface 6 Contents 9 1 Introduction 13 1.1 Short History: Classical Tools Versus Lasers Tools 14 1.2 Solid Materials (Metals, Semiconductors, Dielectrics) to be Processed by PLA 18 1.2.1 Thermally Well-Conducting Materials 19 1.2.2 Wide-Bandgap Materials, Glasses, Polymers 20 1.3 Practical Applications of PLA and General Aims 20 1.3.1 PLD 20 1.3.2 Cluster Formation by PLA 21 References 23 2 Lasers for Pulsed Laser Ablation 26 2.1 CO2, Nd-YAG, Ti--Sapphire, Excimers Lasers 26 2.1.1 Nd-YAG Laser 28 2.1.2 Ti-Sapphire Laser 31 2.1.3 Excimer Laser 33 2.1.4 CO2 Laser 34 2.2 Nano, Pico, Femtosecond Lasers. Q-Switched and Mode Locked Lasers 36 2.2.1 Nano, Pico, Femtosecond Lasers 36 2.2.2 Q-Switched and Mode Locked Lasers 39 2.3 Laser Parameters to be Controlled in PLA for Different Types of Solid Materials 50 2.4 Basic Experimental Setup for PLA 55 2.4.1 Combined Irradiation Methods 57 2.4.2 Projection Through Microlens Array 58 2.4.3 Laser Trepanning 59 References 60 3 Laser-Matter Interaction Below the Plasma Ignition Threshold Intensity 63 3.1 Linear and Non-linear Phenomena Involved in Laser-Matter Interaction 64 3.1.1 Second Order Nonlinear Effects 64 3.1.2 Third-Order Nonlinear Effects 66 3.1.3 Photoionization 70 3.2 Experimental Methods for Analyzing the Main Phenomena Involved in Laser-Matter Interaction During PLA Below the Plasma Ignition Threshold: Reflectometry, Analysis of Thermal Radiation 71 3.3 Theoretical Models for PLA Below the Plasma Ignition Threshold 75 3.3.1 Semi-Quantitative Analytical Models 77 3.3.2 Numerical Photo-Thermal Models for Short Laser Pulses 81 References 84 4 Laser-Matter Interaction Above the Plasma Ignition Threshold Intensity 87 4.1 Main Phenomena Involved in Production of the Ablation Plasma and in Laser-Plasma Interaction During PLA: Plasma Formation and Evolution 88 4.1.1 Plasma Heating, Self Focusing, Critical Density, Shielding 90 4.1.2 Ablation Plume Expansion 92 4.1.3 Interaction of Plasma Plume with Obstacles 103 4.2 Experimental Methods for Analyzing the Main Phenomena Involved in Laser-Plasma Interaction: Optical and Mass Spectroscopy, High Speed Imaging 105 4.2.1 Interferometric Methods 106 4.2.2 Thomson-Scattering 114 4.2.3 Spectrometric Methods 122 4.2.4 Laser Induce Fluorescence (LIF) Spectroscopy 129 4.2.5 Mass Spectrometry (MS) 133 4.3 Theoretical Models for Plasma Mediated PLA 139 4.3.1 Numerical Photo-Thermal Models 139 4.3.2 Numerical Photo-Thermal-Hydrodynamical Models for Plume Expansion and Material Removal 146 References 148 5 Material Removal and Deposition by Pulsed Laser Ablation and Associated Phenomena 152 5.1 Micro and Nano Processing (Patterning) of Materials by PLA 152 5.1.1 Irradiation in Non-reactive Atmosphere 154 5.1.2 PLA in Gaseous and Liquid Etching Medium 160 5.2 Nanoparticles Production 166 5.2.1 Nanoparticles Growing Mechanism 166 5.2.2 Parameter Control 167 5.2.3 Limitations 169 5.3 Pulsed Laser Deposition 169 5.3.1 Ablation 171 5.3.2 Propagation 173 5.3.3 Deposition 174 5.3.4 Plume Filtering 174 5.3.5 Shutter Technique 176 5.3.6 Geometrical Techniques 179 5.3.7 Axe-off Deposition 180 5.3.8 Back-Side Deposition 182 5.3.9 Plane Mask Technique 184 5.3.10 Multiple Element Masks Filtering 190 5.3.11 Helical Mask 193 5.3.12 Plume Reflection Technique 197 5.4 Harmonics Generation in Solids, Liquids and Gases 202 5.4.1 Low-Order Harmonics Generation 202 5.4.2 High Harmonics Generation from Solid Density Plasmas 208 5.4.3 Coherent Wake Emission Harmonics 213 5.4.4 Relativistic Oscillating Mirror Harmonics 215 References 219 6 Experimental Techniques for Analyzing the Material Removal and Deposition Rates in Real Time 224 6.1 Optoacoustics and Interferometric Methods for Real Time 224 6.2 Spectroscopy of the Ablation Plasma as a Real Time 228 6.3 Microbalances for Real Time Monitor of the Ablation 230 References 233 7 Conclusion 234 References 238 Subject Index 239 Front Matter....Pages i-xii Introduction....Pages 1-13 Lasers for Pulsed Laser Ablation....Pages 15-51 Laser-Matter Interaction Below the Plasma Ignition Threshold Intensity....Pages 53-76 Laser-Matter Interaction Above the Plasma Ignition Threshold Intensity....Pages 77-141 Material Removal and Deposition by Pulsed Laser Ablation and Associated Phenomena....Pages 143-214 Experimental Techniques for Analyzing the Material Removal and Deposition Rates in Real Time....Pages 215-224 Conclusion....Pages 225-229 Back Matter....Pages 231-233