Principles of Semiconductor Devices

Description

The dimensions of modern semiconductor devices are reduced to the point where classical semiconductor theory, including the concepts of continuous particle concentration and continuous current, becomes questionable. Further questions relate to two-dimensional transport in the most important field-effect devices and one-dimensional transport in nanowires and carbon nanotubes.

Designed for upper-level undergraduate and graduate courses, Principles of Semiconductor Devices, Second Edition, presents the semiconductor-physics and device principles in a way that upgrades classical semiconductor theory and enables proper interpretations of numerous quantum effects in modern devices. The semiconductor theory is directly linked to practical applications, including the links to the SPICE models and parameters that are commonly used during circuit design.

The text is divided into three parts: Part I explains semiconductor physics; Part II presents the principles of operation and modeling of the fundamental junctions and transistors; and Part III provides supplementary topics, including a dedicated chapter on the physics of nanoscale devices, description of the SPICE models and equivalent circuits that are needed for circuit design, introductions to the most important specific devices (photonic devices, JFETs and MESFETs, negative-resistance diodes, and power devices), and an overview of integrated-circuit technologies. The chapters and the sections in each chapter are organized so as to enable instructors to select more rigorous and design-related topics as they see fit.

New to this Edition

• A new chapter on the physics of nanoscale devices
• A revised chapter on the energy-band model and fully reworked and updated material on crystals to include graphene and carbon nanotubes
• A revised P-N junction chapter to emphasize the current mechanisms that are relevant to modern devices
• JFETs and MESFETs in a stand-alone chapter
• Fifty-seven new problems and eleven new examples

Table of Contents

Contents
PART I INTRODUCTION TO SEMICONDUCTORS
1 lNTRODUCTION TO CRYSTALS AND CURRENT CARRIERS
IN SEMICONDUCTORS, THE ATOMIC-BOND MODEL
1.1 INTRODUCTION TO CRYSTALS
1.1.1 Atomic Bonds
1.1.2 Three-Dimensional Crystals
1.1.3 Two-Dimensional Crystals: Graphene and Carbon Nanotubes
1.2 CURRENT CARRIERS
1.2.1 Two Types of Current Carriers in Semiconductors
1.2.2 N·Type and P-Type Doping
1.2.3 Electroneutrality Equation
1.2.4 Electron and Hole Generation and Recombination in Thermal Equilibrium
1.3 BASICS OF CRYSTAL GROWTH AND DOPING TECHNIQUES
1.3.1 Crystal-Growth Techniques
1.3.2 Doping Techniques
Summary
Problems
Review Questions

2 THE ENERGY-BAND MODEL
12.1 ELECTRONS AS WAVES
2.1.1 De Broglie Relationship Between Particle and Wave Properties
2.1.2 Wave Function and Wave Packet
2.1.3 Schrodinger Equation
2.2 ENERGY LEVELS IN ATOMS AND ENERGY BANDS IN CRYSTALS
2.2.1 Atomic Structure
2.2.2 Energy Bands in Metals
2.2.3 Energy Gap and Energy Bands in Semiconductors and Insulators
12.3 ELECTRONS AND HOLES AS PARTICLES
2.3.1 Effective Mass and Real E-k Diagrams
2.3.2 The Question of Electron Size: The Uncertainty Principle
2.3.3 Density of Electron States
2.4 POPULATION OF ELECTRON STATES, CONCENTRATIONS OF
ELECTRONS A:"D HOLES
2.4.1 Fermi-Dirac Distribution
2.4.2 Maxwell-Boltzmann Approximation and Effective Density of States
2.4.3 Fermi Potential and Doping
2.4.4 Nonequilibrium Carrier Concentrations and Quasi-Fermi Levels
Summary
Problems
Review Questions

3 DRIFT
3.1 ENERGY BANDS WITH APPLIED ELECTRIC FIELD
3.1.1 Energy-Band Presentation of Drift Current
3.1.2 Resistance and Power Dissipation due to Carrier Scattering
3.2 OHM'S LAW, SHEET RESISTANCE, AND CONDUCTIVITY
3.2.1 Designing Integrated-Circuit Resistors
3.2.2 Differential Form of Ohm's Law
3.2.3 Conductivity Ingredients
3.3 CARRIER MOBILITY
3.3.1 Thermal and Drift Velocities
3.3.2 Mobility Definition
3.3.3 Scattering Time and Scattering Cross Section
3.3.4 Mathieson's Rule
°3.3.5 Hall Effect
Summary
Problems
Review Questions

4 DlFFUSION
4.1 DIFFUSION-CURRENT EQUATION
4.2 DIFFUSION COEFFICIENT
4.2.1 Einstein Relationship

• 4.2.2 Haynes-Shockley Experiment
  4.2.3 Arrhenius Equation
  4.3 BASIC CONTINUITY EQUATION
  Summary
  Problems
  Review Questions
  
  5 GENERATION AND RECOMBINATION
  5.1 GENERATION AND RECOMBINATION MECHANISMS
  5.2 GENERAL FORM OF THE CONTINUITY EQUATION
  5.2.1 Recombination and Generation Rates
  5.2.2 Minority-Carrier Lifetime
  5.2.3 Diffusion Length
  5.3 GENERATION AND RECOMBINATION PHYSICS AND SHOCKLEYREAD-
  HALL (SRH) THEORY
  5.3.1 Capture and Emission Rates in Thermal Equilibrium
  5.3.2 Steady-State Equation for the Effective Thermal Generation/Recombination
  Rate
  5.3.3 Special Cases
  5.3.4 Surface Generation and Recombination
  Summary
  Problems
  Review Questions
  
  PART II FUNDAMENTAL DEVICE STRUCTURES
  6 P-N JUNCTION
  6.1 P-N JUNCTION PRINCIPLES
  6.1.1 p-~ Junction in Thermal Equilibrium
  6.1.2 Reverse-Biased P-N Junction
  6.1.3 Forward-Biased P-K Junction
  6.1.4 Breakdown Phenomena
  6.2 DC MODEL
  6.2.1 Basic Current-Voltage (I-V) Equation
  6.2.2 Important Second-Order Effects
  6.2.3 Temperature Effects
  6.3 CAPACITA CE OF REVERSE-BIASED P-:-I JUNCTION
  6.3.1 C-V Dependence
  6.3.2 Depletion-Layer Width: Solving the Poisson Equation
  6.3.3 SPICE Model for the Depletion-Layer Capacitance
  6.4 STORED-CHARGE EFFECTS
  6.4.1 Stored Charge and Transit Time
  6.4.2 Relationship Between the Transit Time and the Minority-Carrier
  Lifetime
  6.4.3 Switching Characteristics: Reverse-Recovery Time
  Summary
  Problems
  Review Questions
  
  7 METAL-SEMICONDUCTOR CONTACT AND MOS CAPACITOR
  7.1 METAL-SEMICONDUCTOR CONTACT
  7.1.1 Schottky Diode: Rectifying Metal-Semiconductor Contact
  7.1.2 Ohmic Metal-Semiconductor Contacts
  7.2 MOS CAPACITOR
  7.2.1 Properties of the Gate Oxide and the Oxide-Semiconductor Interface
  7.2.2 C-V Curve and the Surface-Potential Dependence on Gate Voltage
  7.2.3 Energy-Band Diagrams
  ·7.2.4 Flat4Band Capacitance and Debye Length
  Summary
  Problems
  Review Questions
  
  8 MOSFET
  8.1 MOSFET PRINCIPLES
  B.1.1 MOSFET Structure
  8.1.2 MOSFET as a Voltage-Controlled Switch
  B.1.3 The Threshold Voltage and the Body Effect
  B.1.4 MOSFET as a Voltage-Controlled Current Source: Mechanisms of
  Current Saturation
  8.2 PRINCIPAL CURRENT-VOLTAGE CHARACTERISTICS AND EQUATIONS
  8.2.1 SPICE LEVEL 1 Model
  8.2.2 SPICE LEVEL 2 Model
  8.2.3 SPICE LEVEL 3 Model: Principal Effects
  8.3 SECO:\D-OROER EFFECTS
  8.3.1 Mobility Reduction with Gate Voltage
  8.3.2 Velocity Saturation (Mobility Reduction with Drain Voltage)
  8.3.3 Finite Output Resistance
  8.3.4 Threshold-Voltage-Related Short-Channel Effects
  8.3.5 Threshold Voltage Related Narrow-Channel Effects
  8.3.6 Subthreshold Current
  8.4 Nanoscale MOSFETs
  8.4.1 Down-Scaling Benefits and Rules
  8.4.2 Leakage Currents
  8.4.3 Advanced MOSFETs
  "8.5 MOS-BASED MEMORY DEVICES
  8.5.1 1C1T DRAM Cell
  8.5.2 Flash-Memory Cell
  Summary
  Problems
  Review Questions
  
  9 BJT
  9.1 B.JT PRINCIPLES
  9.1.1 BJT as a Voltage-Controlled Current Source
  9.1.2 BJT Currents and Gain Definitions
  9.1.3 Dependence of ? and ? Current Gains on Technological Parameters
  9.1.4 The Four Modes of Operation: BJT as a Switch
  9.1.5 Complementary BJT
  9.1.6 BJT Versus MOSFET
  9.2 PRINCIPAL CURRENT-VOLTAGE CHARACTERISTICS, EBERE-MOLL
  MODEL IN SPICE
  9.2.1 Injection Version
  9.2.2 Transport Version
  9.2.3 SPICE Version
  9.3 SECOND·ORDER EFFECTS
  9.3.1 Early Effect: Finite Dynamic Output Resistance
  9.3.2 Parasitic Resistances
  9.3.3 Dependence of Common-Emitter Current Gain on Transistor Current:
  Low-Current Effects
  9.3.4 Dependence of Common-Emitter Current Gain on Transistor Current:
  Gummel-Poon Model for High-Current Effects
  9.4 HETEROJUNCTION BIPOLAR TRANSISTOR
  Summary
  Problems
  Review Questions
  
  PART III SUPPLEMENTARY TOPICS
  10 PHYSICS OF NANOSCALE DEVICES
  10.1 SINGLE-CARRIER EVENTS
  10.1.1 Beyond the Classical Principle of Continuity
  10.1.2 Current-Time Form of Uncertainty Principle
  10.1.3 Carrier-Supply Limit to Diffusion Current
  10.1.4 Spatial Uncertainty
  10.1.5 Direct Nonequilibrium Modeling of Single-Carrier Events
  10.2 TWO-DIMENSIONAL TRANSPORT IN MOSFETs AND HEMTs
  10.2.1 Quantum Confinement
  10.2.2 HEMT Structure and Characteristics
  10.2.3 Application of Classical MOSFET Equations to Two-Dimensional
  Transport in MOSFETs and HEMTs
  10.3 ONE-DIMENSUIONAL TRANSPORT IN NANOWIRES AND CARBON
  NANOTUBES
  10.3.1 Ohmic Transport in Nanowire and Carbon-Nanotube FETs
  10.3.2 One-Dimensional Ballistic Transport and the Quantum Conductance
  Limit
  Summary
  Problems
  Review Questions
  
  II DEVICE ELECTRONICS, EQUIVALENT CIRCUITS A D SPICE
  PARAMETERS
  lI.l DIODES
  11.1.1 Static Model and Parameters in SPICE
  11.1.2 Large-Signal Equivalent Circuit in SPICE
  11.1.3 Parameter Measurement
  11.1.4 Small-Signal Equivalent Circuit
  ll.2 MOSFET
  11.2.1 Static Model and Parameters; LEVEL 3 in SPICE
  11.2.2 Parameter Measurement
  11.2.3 Large-Signal Equivalent Circuit and Dynamic Parameters in SPICE
  11.2.4 Simple Digital ~1od.el
  11.2.5 Small-Signal Equivalent Circuit
  11.3 BJT
  11.3.1 Static Model and Parameters: Ebers-Moll and Gummel-Poon Levels
  in SPICE
  11.3.2 Parameter Measurement
  11.3.3 Large-Signal Equivalent Circuit and Dynamic Parameters in SPICE
  11.3.4 Small-Signal Equivalent Circuit
  Summary
  Problems
  Review Questions
  
  12 PHOTONIC DEVICES
  12.1 LIGHT EMITTING DIODES (LED)
  12.2 PHOTODETECTORS AND SOLAR CELLS
  12.2.1 Biasing for Photodetector and Solar-Cell Applications
  12.2.2 Carrier Generation in Photodetectors and Solar Cells
  12.2.3 Photocurrent Equation
  12.3 LASERS
  12.3.1 Stimulated Emission, Inversion Population, and Other Fundamental Concepts
  12.3.2 A Typical Heterojunction Laser
  Summary
  Problems
  Review Questions
  
  13 JFET AND MESFET
  13.1 JFET
  13.1.1 JFET Structure
  13.1.2 JFET Characteristics
  13.1.3 SPICE Model and Parameters
  13.2 MESFET
  13.2.1 MESFET Structure
  13.2.2 MESFET Characteristics
  13.2.3 SPICE Model and Parameters
  Summary
  Problems
  Review Questions
  
  14 POWER DEVICES
  14.1 POWER DIODES
  14.1.1 Drift Region in Power Devices
  14.1.2 Switching Characteristics
  14.1.3 Schottky Diode
  14.2 POWER MOSFET
  14.3 IGBT
  14.4 THYRISTOR
  Summary
  Problems
  Review Questions
  
  15 NEGATIVE RESISTANCE DIODES
  15.1 AMPLIFICATION AI'D OSCILLATION BY NEGATIVE DYNAMIC
  RESISTANCE
  15.2 GUNN DIODE
  15.3 IMPATT DIODE
  15.4 TUNNEL DIODE
  Summary
  Problems
  Review Questions
  
  16 INTEGRATED-CIRCUIT TECHNOLOGIES
  16.1 A DIODE IN IC TECHNOLOGY
  16.1.1 Basic Structure
  16.1.2 Lithography
  16.1.3 Process Sequence
  16.1.4 Diffusion Profiles
  16.2 MOSFET TECHNOLOGIES
  16.2.1 Local Oxidation of Silicon (LOCOS)
  16.2.2 NMOS Technology
  16.2.3 Basic CMOS Technology
  16.2.4 Silicon-on-Insulator (SOl) Technology
  16.3 BIPOLAR IC TECHNOLOGIES
  16.3.1 IC Structure of NPN BJT
  16.3.2 Standard Bipolar Technology Process
  16.3.3 Implementation of PNP BJTs, Resistors, Capacitors, and Diodes
  16.3.4 Parasitic IC Elements not Included in Device Models
  16.3.5 Layer Merging
  16.3.6 BiCMOS Technology
  Summary
  Problems
  Review Questions