2nd Edition
Plasma Electronics Applications in Microelectronic Device Fabrication
Beyond enabling new capabilities, plasma-based techniques, characterized by quantum radicals of feed gases, hold the potential to enhance and improve many processes and applications. Following in the tradition of its popular predecessor, Plasma Electronics, Second Edition: Applications in Microelectronic Device Fabrication explains the fundamental physics and numerical methods required to bring these technologies from the laboratory to the factory.
Emphasizing computational algorithms and techniques, this updated edition of a popular monograph supplies a complete and up-to-date picture of plasma physics, computational methods, applications, and processing techniques. Reflecting the growing importance of computer-aided approaches to plasma analysis and synthesis, it showcases recent advances in fabrication from micro- and nano-electronics, MEMS/NEMS, and the biological sciences.
A helpful resource for anyone learning about collisional plasma structure, function, and applications, this edition reflects the latest progress in the quantitative understanding of non-equilibrium low-temperature plasma, surface processing, and predictive modeling of the plasma and the process. Filled with new figures, tables, problems, and exercises, it includes a new chapter on the development of atmospheric-pressure plasma, in particular microcell plasma, with a discussion of its practical application to improve surface efficiency.
The book provides an up-to-date discussion of MEMS fabrication and phase transition between capacitive and inductive modes in an inductively coupled plasma. In addition to new sections on the phase transition between the capacitive and inductive modes in an ICP and MOS-transistor and MEMS fabrications, the book presents a new discussion of heat transfer and heating of the media and the reactor.
Integrating physics, numerical methods, and practical applications, this book equips you with the up-to-date understanding required to scale up lab breakthroughs into industrial innovations.
Introduction
Plasma and Its Classification
Application of Low Temperature Plasma
Academic Fusion
References
Phenomenological Description of the Charged Particle Transport
Transport in Real (Configuration) Space
Momentum Balance of Electrons
Energy Balance of Electrons
Transport in Velocity Space
Electron Velocity Distribution and Swarm Parameters
Ion Velocity Distribution and Mean Energy
Thermal Equilibrium and its Governing Relations
Boltzmann Distribution in Real Space
Maxwell Distribution in Velocity Space
References
Macroscopic Plasma Characteristics
Introduction
Quasi Neutrality
Charge separation In Plasmas
Spatial Scale of Charge-Separation
Time Scale for Charge-Separation
Plasma Shielding
Debye Shielding
Metal Probe in a Plasma
Particle Diffusion
Ambipolar Diffusion
Spatial and Time Scale of Diffusion
Bohm Sheath Criterion
Bohm Velocity
Floating Potential
References
Elementary Processes in Gas Phase and on Surfaces
Particles and Waves
Particle Representation in Classical and Quantum Mechanics
Locally Isolated Particle Group and Wave Packets
Collisions and Cross Sections
Conservation Laws in Collisions
Definition of Collision Cross Sections
The Distribution of Free Paths
Representation of Collisions in Laboratory and CM Reference Frames
Classical Collision Theory
Scattering in Classical Mechanics
Conditions for the Applicability of the Classical Scattering Theory
Quantum Theory Of Scattering
Differential Scattering Cross Section σ(θ)
Modified Effective Range Theory in Electron Scattering
Collisions Between Electrons And Neutral Atoms/Molecules
Resonant Scattering
Electron–Atom Collisions
Energy Levels of Atoms
Electron–Atom Scattering Cross Sections
Electron–Molecule Collisions
Rotational, Vibrational, and Electronic Energy Levels of Molecules
Rotational Excitation
Rotational Energy Levels
Rotational Excitation Cross Sections
Vibrational Excitation
Vibrational Energy Levels
Vibrational Cross Sections
Electronic Excitation and Dissociation
Electronic States of Molecules
Cross Sections for Electronic Excitation of Molecules
Electron Collisions with Excited Atoms and Molecules
Nonconservative Collisions of Electrons With Atoms and Molecules
Electron-Induced Ionization
Electron Attachment
Dissociative Electron Attachment
Nondissociative Electron Attachment
Ion Pair Formation
Electron Attachment to Excited Molecules
Rate Coefficients for Attachment
Electron–Ion and Ion–Ion Recombination
Electron–Ion and Electron–Electron Collisions
Heavy Particle Collisions
Ion–Molecule Collisions
Charge Transfer, Elastic, and Inelastic Scattering of Ions
Ion–Molecule Reactions
Collisions of Fast Neutrals
Collisions of Excited Particles
Chemi-Ionization and Penning Ionization
Collisions of Slow Neutrals and Rate Coefficients
Quenching and Transport of Excited States
Kinetics of Rotational and Vibrational Levels
Photons in Ionized Gases
Emission and Absorption of Line Radiation
Resonant Radiation Trapping
Elementary Processes at Surfaces
Energy Levels of Electrons in Solids
Emission of Electrons from Surfaces
Photo-Emission
Thermionic Emission
Field-Induced Emission
Potential Ejection of Electrons from Surfaces by Ions and Excited Atoms
Emission of Ions and Neutrals from Surfaces
Surface Neutralization
Surface Ionization
Adsorption
References
The Boltzmann Equation and Transport Equations of Charged Particles
Introduction
The Boltzmann Equation
Transport in Phase Space and Derivation of the Boltzmann Equation
Transport Coefficients
The Transport Equation
Conservation of Number Density
Conservation of Momentum
Conservation of Energy
Collision Term In The Boltzmann Equation
Collision Integral
Collision Integral between an Electron and a Gas Molecule
Elastic Collision Term Jelas
Excitation Collision Term Jex
Ionization Collision Term Jion
Electron Attachment Collision Term Jatt
Boltzmann Equation For Electrons
Spherical Harmonics and Their Properties
Velocity Distribution of Electrons
Velocity Distribution under Uniform Number Density: g0
Velocity Distribution Proportional to ∇rn(r, t): g1
Electron Transport Parameters
References
General Properties of Charged Particle Transport in Gases
Introduction
Electron Transport In DC Electric Fields
Electron Drift Velocity
Diffusion Coefficients
Mean Energy of Electrons
Excitation, Ionization, and Electron Attachment Rates
Electron Transport in Radio Frequency Electric Fields
Relaxation Time Constants
Effective Field Approximation
Expansion Procedure
Direct Numerical Procedure
Time-Varying Swarm Parameters
Ion Transport In Dc Electric Fields
References
Modeling of Nonequilibrium (Low Temperature) Plasmas
Introduction
Continuum Models
Governing Equations of a Continuum Model
Local Field Approximation (LFA)
Quasi-Thermal Equilibrium (QTE) Model
Relaxation Continuum (RCT) Model
Phase Space Kinetic Model
Particle Models
Monte Carlo Simulations (MCSs)
Particle-in-Cell (PIC) and Particle-in-Cell/Monte Carlo Simulation (PIC/MCS) Models
Hybrid Models
Circuit Model
Equivalent Circuit Model in CCP
Equivalent Circuit Model in ICP
Transmission-Line Model (TLM)
Electromagnetic Fields and Maxwell’s Equations
Coulomb’s Law, Gauss’s Law, and Poisson’s Equation
Faraday’s Law
Ampere’s Law
Maxwell’s Equations
References
Numerical Procedure of Modeling
Time Constant of the System
Collision-Oriented Relaxation Time
Plasma Species-Oriented Time Constant
Plasma-Oriented Time Constant/Dielectric Relaxation Time
Numerical Techniques To Solve The Time Dependent Drift
Diffusion Equation
Time-Evolution Method
Finite Difference
Digitalization and Stabilization
Time Discretization and Accuracy
Scharfetter–Gummel Method
Cubic Interpolated Pseudoparticle Method
Semi-Implicit Method for Solving Poisson’s Equation
Boundary Conditions
Ideal Boundary — Without Surface Interactions
Dirichlet Condition
Neumann Condition
Periodicity Condition
Electrode Surface
Metallic Electrode
Dielectric Electrode
Boundary Conditions with Charge Exchange
Boundary Conditions with Mass Transport
Plasma Etching
Plasma Deposition
Plasma Sputtering
Moving Boundary under Processing
References
Capacitively Coupled Plasma
Radio Frequency Capacitive Coupling
Mechanism of Plasma Maintenance
Low-Frequency Plasma
High-Frequency Plasma
Electronegative Plasma
Very High-Frequency Plasma
Two-Frequency Plasma
Pulsed Two-Frequency Plasma
References
Inductively Coupled Plasma
Radio Frequency Inductive Coupling
Mechanism of Plasma Maintenance
E-mode and H-mode
Mechanism of Plasma Maintenance
Effect of Metastables
Function of ICP
Phase Transition Between E-Mode and H-Mode in an ICP
Wave Propagation in Plasmas
Plasma and Skin Depth
ICP and the Skin Depth
References
Magnetically Enhanced Plasma
Direct Current Magnetron Plasma
Unbalanced Magnetron Plasma
Radio Frequency Magnetron Plasma
Magnetic Confinements Of Plasmas
Magnetically Resonant Plasmas
References
Plasma Processing and Related Topics
Introduction
Physical Sputtering
Target Erosion
Sputtered Particle Transport
Plasma Chemical Vapor Deposition
Plasma CVD
Large-Area Deposition with High Rate
Plasma Etching
Wafer Bias
On Electrically Isolated Wafers (without Radio-Frequency Bias)
On Wafers with Radio-Frequency Bias
Selection of Feed Gas
Si or Poly-Si Etching
Al Etching
SiO2 Etching
Feature Profile Evolution
Plasma Bosch Process
Charging Damage
Surface Continuity and Conductivity
Charging Damage to Lower Thin Elements in ULSI
Thermal Damage
Specific Fabrication of MOS Transistor
Gate Etching
Contact Hole Etching
Low-K Etching
MEMS Fabrication
References
Atmospheric Pressure, Low Temperature Plasma
High Pressure, Low Temperature Plasma
Fundamental Process
Historical Development
Micro Plasma
Radiofrequency Atmospheric Micro-Plasma Source
Gas Heating in a Plasma
Effect of Local Gas Heating
References
Index
Biography
Toshiaki Makabe received his BSc, MSc, and Ph.D. degrees in electrical engineering all from Keio University. He became a Professor of Electronics and Electrical Engineering in the Faculty of Science and Technology at Keio University in 1991. He also served as a guest professor at POSTECH, Ruhr University Bochum, and Xi’an Jiaotong University. He was Dean of the Faculty of Science and Technology and Chair of the Graduate School from 2007 to 2009. Since 2009, he has been the Vice-President of Keio University in charge of research. He has published more than 170 papers in peer-reviewed international journals, and has given invited talks at more than 80 international conferences in the field of non-equilibrium, low-temperature plasmas and related basic transport theory, and surface processes. He is on the editorial board of Plasma Sources Science and Technology, and many times he has been a guest editor of the special issue about the low temperature plasma and the surface process of the Japanese Journal of Applied Physics, Australian Journal of Physics, Journal of Vacuum Science and Technology A, IEEE Transactions on Plasma Science, and Applied Surface Science, etc. He received the awards; "Fluid Science Prize" in 2003 from the Institute of Fluid Science, Tohoku University, "Plasma Electronics Prize" in 2004 from the Japan Society of Applied Physics, "Plasma Prize" in 2006 from the American Vacuum Society, etc. He is an associate member of the Science Council of Japan, and a foreign member of the Serbian Academy of Sciences and Arts. He is a fellow of the Institute of Physics, the American Vacuum Society, the Japan Society of Applied Physics, and the Japan Federation of Engineering Societies.
Zoran Lj. Petrovic obtained his Master’s degree in the Department of Applied Physics, Faculty of Electrical Engineering in the University of Belgrade, and earned his Ph.D from Australian National University. He is the Head of the Department of Experimental Physics in the Institute of Physics, University of Belgrade. He has taught postgraduate courses in microelectronics, plasma kinetics and diagnostics and was a visiting professor in Keio University (Yokohama, Japan). He has received the Nikola Tesla award for technological achievement and the Marko Jaric Award for Great Achievement in Physics. He is a full member of the Academy of Engineering Sciences of Serbia and Serbian Academy of Sciences and Arts where he chairs the department of engineering science. Zoran Petrovic is a fellow of American Physical Society, vice president of the National Scientific Council of Serbia, and president of the Association of Scientific Institutes of Serbia. He is a member of editorial boards of Plasma Sources Science and Technology and Europena Physical Journal D. He has authored or co-authored over 220 papers in leading international scientific journals, and has given more than 90 invited talks at professional conferences. His research interests include atomic and molecular collisions in ionized gases, transport phenomena in ionized gases, gas breakdown, RF and DC plasmas for plasma processing, plasma medicine, positron collisions and traps, and basic properties of gas discharges.
"This text serves both the expert and the newcomer with background and state-of-the-art knowledge of plasma electronics. It should be on the bookshelf of anyone exploiting plasma technology for device fabrication. Clearly written and well illustrated, it is also suitable as a postgraduate teaching text and, having been updated, may be a standard reference for the next decade."
—Nigel J. Mason, Professor, Department of Physical Sciences, The Open University"This book is a unique and invaluable source of insight and clarity with special strengths in treating charged particle-neutral collisions, rigorously generalized with proper kinetic theory. This rigor in analyzing discharge physics fundamentals makes the subsequent treatment of plasma modeling and surface modification applications in microelectronics even more valuable. It will no doubt become a standard reference for all scientists and engineers interested in weakly ionized, non-equilibrium plasmas."
—David B. Graves, Professor and Lam Research Distinguished Chair, Department of Chemical and Biomolecular Engineering, University of California, Berkeley"… unique in the low-temperature plasma literature for the breadth of its aims and wide-ranging scope, and I would strongly recommend as a reference for postgraduate students in the field."
—Robert E. Robson, Professor, James Cook University"This book discusses the fundamental principles of partially ionized, chemically reactive plasma discharges and their use in thin film processing … a well-written book for plasma engineers and scientists. … [they] will benefit a lot from this book …"
—Hong-Young Chang, Professor, Korean Advanced Institute of Science and Technology (KAIST)"A unique textbook written by two of the most outstanding scientists in the field … A very valuable part of the book is devoted to modeling and numerical simulation … an indispensable source of knowledge and an excellent reference for all kinds of basic phenomena."
—Uwe Czarnetzki, Professor and Chair, Faculty of Physics and Astronomy, Ruhr-Universität Bochum"The book offers a truly excellent account on the fundamental physics of low-temperature plasmas and applications of low-temperature plasmas to other scientific disciplines and technologies. I strongly recommend this book to both newcomers as a high-standard introductory textbook and experts as a comprehensive reference."
—Satoshi Hamaguchi, Professor, Center for Atomic and Molecular Technologies, Osaka University