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A modern take on microelectronic device engineering. Microelectronics is a 50-year-old engineering discipline still undergoing rapid evolution and societal adoption. Integrated Microelectronic Devices: Physics and Modeling fills the need for a rigorous description of semiconductor device physics that is relevant to modern nanoelectronics. The central goal is to present the fundamentals of semiconductor device operation with relevance to modern integrated microelectronics. Emphasis is devoted to frequency response, layout, geometrical effects, parasitic issues and modeling in integrated microelectronics devices (transistors and diodes). In addition to this focus, the concepts learned here are highly applicable in other device contexts. This book is based on my experience in teaching 6.720J/3.43J Integrated Microelectronic Devices, a semester-long graduate student subject jointly offered in the Departments of Electrical Engineering and Computer Science (EECS) and Materials Science and Engineering (MS&E) at Massachusetts Institute of Technology (MIT). Typically, the class is composed of graduate students in EECS, Materials Science, Mechanical Engineering, Chemical Engineering and Physics plus a few seniors in the same departments. Graduate students in EECS and MS&E with interest in semiconductor materials and devices are strongly encouraged to take this subject their very first semester at MIT. While the book originated in a graduate course at MIT, it has been constructed to be productively used in an advanced undergraduate subject at the junior/senior level, as explained below. The central goal of this book is to present the fundamentals of semiconductor device operation with relevance to modern integrated microelectronics (as opposed to, say, photonics, energy conversion devices, or power electronics). This means that no optical devices nor power devices of any kind are described. In contrast, emphasis is devoted to frequency response, layout, geometrical effects, parasitic issues and modeling in integrated microelectronics devices (transistors and diodes). In spite of this focus, the concepts learned here are highly applicable in other device contexts. This book should be a great resource for a broad range of students with a diverse set of interests. Contents Preface xv About the Author xix 1 Electrons, Photons, and Phonons Selected Concepts of Quantum Mechanics The dual nature of the photon The dual nature of the electron Electrons in confined environments Selected Concepts of Statistical Mechanics Thermal motion and thermal energy Thermal equilibrium Electron statistics Selected Concepts of Solid-State Physics Bonds and bands Metals, insulators, and semiconductors Density of states Lattice vibrations: phonons Summary Further reading Problems Carrier Statistics in Equilibrium Conduction and Valence Bands-- Bandgap-- Holes Intrinsic Semiconductor Extrinsic Semiconductor Donors and acceptors Charge neutrality Equilibrium carrier concentration in a doped semiconductor Carrier Statistics in Equilibrium Conduction and valence band density of states Equilibrium electron concentration Equilibrium hole concentration np product in equilibrium Location of Fermi level Summary Further Reading Problems Carrier Generation and Recombination Generation and Recombination Mechanisms Thermal Equilibrium: Principle of Detailed Balance Generation and Recombination Rates in Thermal Equilibrium Band-to-band optical generation and recombination Auger generation and recombination Trap-assisted thermal generation and recombination Generation and Recombination Rates Outside Equilibrium Quasi-neutral low-level injection-- recombination lifetime Extraction-- generation lifetime Dynamics of Excess Carriers in Uniform Situations Example 1: Turn-on transient Example 2: Turn-off transient Example 3: A pulse of light Surface Generation and Recombination Summary Further Reading Problems 4 Carrier Drift and Diffusion Thermal Motion Thermal velocity Scattering Drift Drift velocity Velocity saturation Drift current Energy band diagram under electric field Diffusion Fick's first law The Einstein relation Diffusion current Transit Time Nonuniformly Doped Semiconductor in Thermal Equilibrium Gauss' law The Boltzmann relations Equilibrium carrier concentration Quasi-Fermi Levels and Quasi-Equilibrium Summary Further Reading Problems 5 Carrier Flow Continuity Equations Surface Continuity Equations Free surface Ohmic contact Shockley Equations Simplifications of Shockley Equations to One-Dimensional Quasi-Neutral Situations Majority-Carrier Situations Example 1: Semiconductor bar under voltage Example 2: Integrated resistor Minority-Carrier Situations Example 3: Diffusion and bulk recombination in a "long" bar Example 4: Diffusion and surface recombination in a "short" bar Length scales of minority carrier situations Dynamics of Majority-Carrier Situations Dynamics of Minority-Carrier Situations Example 5: Transient in a bar with S = â Transport in Space-Charge and High-Resistivity Regions Example 6: Drift in a high-resistivity region under external electric field Comparison between SCR and QNR transport Carrier Multiplication and Avalanche Breakdown Example 7: Carrier multiplication in a high-resistivity region with uniform electric field Summary Further Reading Problems PN Junction Diode The Ideal PN Junction Diode Ideal PN Junction in Thermal Equilibrium Current-Voltage Characteristics of The Ideal PN Diode Electrostatics under bias I-V characteristics: qualitative discussion I-V characteristics: quantitative models Charge-Voltage Characteristics of Ideal PN Diode Depletion charge Minority carrier charge Equivalent Circuit Models of The Ideal PN Diode Nonideal and Second-Order Effects Short diode Space-charge generation and recombination Series resistance Breakdown voltage Nonuniform doping distributions High-injection effects Integrated PN Diode Isolation Series resistance High-low junction Summary Further Reading Problem Schottky Diode and Ohmic Contact The Ideal Schottky Diode Ideal Schottky Diode in Thermal Equilibrium A simpler system: a metal-metal junction Energy band lineup of metal-semiconductor junction Electrostatics of metal-semiconductor junction in equilibrium Current-Voltage Characteristics of Ideal Schottky Electrostatics under bias I-V characteristics: qualitative discussion I-V characteristics: thermionic emission model Charge-Voltage Characteristics of Ideal Schottky Diode Equivalent Circuit Models for The Ideal Schottky Diode Nonideal and Second-Order Effects Series resistance Breakdown voltage Integrated Schottky Diode Ohmic Contacts Lateral ohmic contact: transmission-line model Boundary conditions imposed by ohmic contacts Summary Further Reading Problems 8 The Si Surface and the Metal-OxideSemiconductor Structure The Semiconductor Surface The Ideal Metal-Oxide-Semiconductor Structure The Ideal Metal-Oxide-Semiconductor Structure at Zero Bias General relations for the electrostatics of the ideal MOS structure Electrostatic of the MOS structure under zero bias The Ideal Metal-Oxide Semiconductor Structure Under Bias Depletion Flatband Accumulation Threshold Inversion Summary of charge-voltage characteristics Dynamics of The MOS Structure Quasi-static C-V characteristics High-frequency C-V characteristics Deep depletion Weak Inversion and The Subthreshold Regime Three-Terminal MOS Structure Summary Further Reading Problems The "Long" Metal-Oxide-Semiconductor Field-Effect Transistor The Ideal MOSFET Qualitative Operation of The Ideal MOSFET Inversion Layer Transport in The Ideal MOSFET Current-Voltage Characteristics of The Ideal MOSFET The cut-off regime 9.4.2 The linear regime The saturation regime DC large-signal equivalent-circuit model of ideal MOSFET Energy band diagrams Charge-Voltage Characteristics of The Ideal MOSFET Depletion charge Inversion charge Small-Signal Behavior of Ideal MOSFET Small-signal equivalent circuit model of ideal MOSFET Short-circuit current-gain cut-off frequency, fT, of ideal MOSFET in saturation Nonideal Effects in MOSFET Body effect Effect of back bias Channel-length modulation The subthreshold regime Source and drain resistance Summary Further Reading Problems The "Short" Metal-Oxide-Semiconductor Field-Effect Transistor MOSFET Short-Channel Effects: Transport Mobility degradation Velocity saturation MOSFET Short-Channel Effects: Electrostatics Threshold voltage dependence on gate length: VT rolloff Threshold voltage dependence on VDS: drain-induced barrier lowering (DIBL) Subthreshold swing dependence on gate length and VDS MOSFET Short-Channel Effects: Gate Stack Scaling Gate capacitance Gate leakage current MOSFET High-Field Effects Electrostatics of velocity saturation region Impact ionization and substrate current Output conductance Gate-induced drain leakage MOSFET Scaling The MOSFET as a switch Constant field scaling of the ideal MOSFET Constant voltage scaling of the ideal MOSFET Generalized scaling of short MOSFETs MOSFET scaling: a historical perspective Evolution of MOSFET design Summary Further Reading Problems The Bipolar Junction Transistor The Ideal BJT Current-Voltage Characteristics of The Ideal BJT The forward-active regime The reverse regime The cut-off regime The saturation regime Output I-V characteristics Charge-Voltage Characteristics of Ideal BJT Depletion charge 1 Minority carrier charge. (source: Nielsen Book Data) Publisher's summary A modern take on microelectronic device engineering Microelectronics is a 50-year-old engineering discipline still undergoing rapid evolution and societal adoption. Integrated Microelectronic Devices: Physics and Modeling fills the need for a rigorous description of semiconductor device physics that is relevant to modern nanoelectronics. The central goal is to present the fundamentals of semiconductor device operation with relevance to modern integrated microelectronics. Emphasis is devoted to frequency response, layout, geometrical effects, parasitic issues and modeling in integrated microelectronics devices (transistors and diodes). In addition to this focus, the concepts learned here are highly applicable in other device contexts. This text is suitable for a one-semester junior or senior-level course by selecting the front sections of selected chapters (e.g. 1-9). It can also be used in a two-semester senior-level or a graduate-level course by taking advantage of the more advanced sections. (source: Nielsen Book Data) There are two distinct parts to this book. The first five chapters introduce fundamental aspects of semiconductor physics pertaining to microelectronic devices: band structure, electron statistics, generation and recombination, drift and diffusion, and minority and majority carrier situations. Each chapter gives in its main body a general description suitable for a junior/senior-level or a first-year graduate course. These chapters also include at the end a number of advanced topics that can be selected individually to provide further depth. These can be the basis of a more advanced graduate subject. Six device chapters follow with a similar outline. After a brief introductory section, the main body of the chapter presents a first-order, physically meaningful description of device physics and operation of an “ideal device”. The ideal device is stripped down to its very essence, preserving the key physics, and is analyzed in a simple and intuitive way. The ideal device, constructed and studied this way, is therefore an excellent vehicle to learn device physics at the junior/senior level. One or more of the following sections present significant non idealities, important second-order effects and other considerations that are relevant in “real” devices. These are suitable topics for graduate courses. To some extent, teachers of graduate subjects will be able to pick and choose topics from these latter sections since they are rather independent of one another. Every chapter finishes with a set of advanced topics that contain more advanced graduate-level material also amenable to individual selection. This text is suitable for a one-semester junior or senior-level course by selecting the front sections of selected chapters (e.g. 1-9). It can also be used in a two-semester senior-level or a graduate-level course by taking advantage of the more advanced sections